KR100326623B1 - Inlet structures for introducing a particulate solids containing and/or solids forming gas stream to a gas processing system - Google Patents

Abstract

The present invention relates to an inlet structure 60 for passing airflow from an upstream source 90 of gas to a downstream point, which not only inhibits the deposition and formation of particles and thin films, but also adversely affects hydrodynamics. Are configured, arranged and operated.

Description

INLET STRUCTURES FOR INTRODUCING A PARTICULATE SOLIDS CONTAINING AND / OR SOLIDS FORMING GAS STREAM TO A GAS PROCESSING SYSTEM}

In the process of treating the particulate solid-containing air stream and / or the particulate solid-forming air stream, it is often a problem that the inlet structure of the processing equipment is blocked by the particulate solid in the air stream. As the particulate solid containing air stream and / or the particulate solid forming air flow flows through the processing equipment, the particulate solid may be deposited on the inner surface and the passageway of the inlet structure.

If particulate solids accumulate as the processing equipment continues to run, the inlet structure of such equipment may be blocked enough to completely block it. Alternatively, the accumulation of such particulate solids may not block the inlet of the processing unit, but the flow of airflow is impaired and the pressure drop in the system is increased to such an extent that the processing equipment is considerably inefficient to achieve its intended purpose. May be

In general, particles associated with the air stream are (i) particles generated in the upstream treatment unit and upstream with the air stream to the downstream inlet structure, (ii) oxygen from the leaks entering the system line, and reaction with the treatment gas component. Particles formed in the system line by means of (iii) particles formed in the system line due to two or more process off-gas reactions during the flow of air to the downstream inlet structure, and (iv) in the inlet structure downstream. Particles formed by (partial) condensation of the blocking gases leading to (v) reaction with the treatment gas, with oxygen or water vapor being despread from, for example, a downstream air flow treatment unit, such as a downstream water scrubber. From various sources, including particles formed by and the like. In some situations where particles are formed by condensation, the problem can be ameliorated by heating the processing line to remove condensable components in the air stream. However, even when the treatment line is heated, problems with particles from other sources still remain.

In particular, in the field of semiconductor manufacturing, (a) the combustion products of downstream oxidation and / or water purification operations used to treat airflow are susceptible to injection water such as BCl ₃ , WF ₆ , DCS, TCS, SiF _4, etc. Backflow into the inlet of water vapor or liquid water by capillary action resulting in a hydrolysis reaction in a heterogeneous or homogeneous manner with the gas, (b) thermal degradation of the heat sensitive injection gases, (c) a transition point in the system The inlet is likely to be clogged due to condensation of the injection gases due to the point).

Due to the inlet blockage problem described above, it is necessary to incorporate a plunger mechanism or other particulate solid removal means in order to prevent particulate solids from accumulating at the inlet. However, these mechanical fasteners add significant cost and labor to the system and can damage the inlet over time. In other cases, clogging of the inlet can affect the entire system and it is necessary to take periodic precautions to ensure that no particulate solids accumulate at the inlet. However, these measures require the system to be shut down, which reduces the productivity of the manufacturing or processing plant to which the inlet is associated.

In the discharge airflow treatment system of a semiconductor process, considering that water vapor or liquid water flows back from the downstream water clarifier to the upstream inlet structure by capillary action, the water vapor discharged from the water clarifier is a conventional flow direction of the treatment airflow. In contrast, the return movement from the water purifier inlet toward the semiconductor processing tool], several mechanisms may be included in the return movement of the water vapor.

One such mechanism is gas-gas interdiffusion. The only practical way to avoid the return movement of water vapor is to add a diffusion boundary to the water purifier inlet.

Another mechanism for this despreading of water vapor is the so-called Richardson effect annular effect. All dry pumps cause some amount of pressure vibration in the air stream. This pressure oscillation results in a backflow transport mechanism that feeds the gas in opposition to the usual gas flow direction. This phenomenon is the result of the boundary layer annular effect. Because of this effect, the reverse flow velocity is greatest where it is a short distance away from the surface of the wall.

If the granular solids continue to accumulate as the processing equipment continues to run, the inlet structure of such equipment may be blocked enough to block the entirety. Alternatively, the accumulation of such particulate solids may not block the inlet of the processing unit but may impair the flow of airflow and increase the pressure drop in the system so that the processing equipment is considerably inefficient to achieve its intended purpose. .

In particular, in the case of water purifiers used to clean air streams such as waste streams generated in the manufacture of semiconductor devices, the waste streams constituting the air stream injected into the water purifier are ultrafine silicas produced by CVD or other deposition operations. It may contain fairly fine particles, such as particles, metal particles, or produce (by reaction or condensation) such particles. Such waste streams tend to clog the inlet of the waste water purifier very easily. As a result, the inlet of the water purifier needs to be frequently cleaned manually.

This easy opening is a major drawback of water purifier units currently used in the semiconductor industry. In this application, the time required for the inlet of the water purifier to be blocked depends on the process and the specific location. Factors affecting the average time it takes for a water purifier to fail due to blockage of the inlet include: a processing tool generating a particle-containing treatment discharge flow to be treated in the water purifier; an upstream stream generating the outflow air stream to be treated in the water purifier Specific process recipes and chemistries used in processing units, inert gas cleaning properties used to flush pumps and processing lines in the system, and the like. There are other treatment conditions and factors suspected of contributing or affecting the accumulation of particles in the treatment system, but not yet clearly defined. Aberu, R., Troup, A., and Sahm, M.'s Low Pressure Chemical Vapor Deposition and Plasma Enhanced Chemical Vapor Deposition Causes Unusual Solid Formation in the Exhaust Systems of Semiconductor Processes ( Causes of anomalous solid formation in the exhaust systems of low-pressure chemical vapor deposition and plasma enhanced chemical vapor deposition semiconductor processes' (July / August 1994, J. Vac. Sci. Technol. B 12 (4), 2763 -2767).

In the case of an operation such as the treatment of gases flowing out during a semiconductor manufacturing operation, the wastes may be oxidized by thermal oxidation or other oxidation reaction process, in order to reduce the oxidizable harmful components of the effluent gas by oxidizing power. By this oxidation, not only the other components that may be harmful when discharged from the treatment plant to the atmosphere can be removed by the oxidizing power, but also the natural and toxic components in the effluent stream can be significantly reduced. .

The effluent gases thus treated may contain fairly fine particles, such as, for example, ultrafine silica particles, metal particles, etc., generated during CVD or other deposition operations, but these air flows at high temperatures typically used in oxidation treatments. Significant gas components may be contained that may be corrosive. These corrosive properties not only lead to problems with the hot effluent air streams present during the oxidation treatment, but also to the problems of solid accumulation that can contribute to the particle content in these effluent air streams.

Particulate solids in this air stream can clog downstream processing equipment, such as downstream processing operations, including, for example, water purification operations. Clogging of the purification equipment is a significant problem in the art. This is particularly a problem when there is a transition from the high temperature oxidation state inherent in the combustion device to the low temperature wet state of the quench chamber. Obviously, there is a transition region where a flow transition from the hot combustion state to the wet cooling state occurs. Problems related to this oxidation / purification / cooling system include problems of accumulation of particles, blockage of the cross section due to despreading of the water sprayed from the wet cooling zone, which produces sticky adherent particles that accumulate in the cooling zone portion just above the wet zone. There is this.

Another problem is the inability to permanently locate the wet / dry interface. Since the position of the wet / dry interface can change as the hydrodynamic state of the system changes, it becomes very difficult to pinpoint the wet / dry interface correspondingly. Factors affecting the location of the interface include (a) combustion gas flow rate and thermal efficiency, (b) cooling spray flow rate and overflow weir flow rate, and (c) the inverse of the cooling spray flow or weir overflow flow. Mixing and swirling. The inability to fix the location of the wet / dry interface results in two problems: That is, (1) areas where particles tend to condense are created, and (2) the materials in the cooling zones can be corroded as a result.

Most alloys used in combustion and cooling equipment are corrosion resistant to certain combinations of conditions. These alloys that withstand high temperature oxidation conditions are typically unsuitable for wet corrosion conditions and vice versa. This problem is exacerbated in the presence of other materials that accelerate corrosion or oxidation, such as halogens, sulfiding agents and the like. Since it is impossible to pinpoint specific transitions of constituent materials, it is necessary to use new constituent materials that are quite expensive but only function at a moderate level.

To solve this problem, considerable effort has been made. Until recently, no acceptable solution was found, and all of the proposed solutions had several drawbacks. Typically, two approaches are used as a matter of necessity. The first method is to use an overflow bank to wet the wall at the transition. The second method is to use submerged quench. The overflow bank performs an optimal operation to prevent the accumulation of particles, but there are three major disadvantages. The overflow banks still have a wet / dry interface at the point of injection of water, so they only do the usual work to prevent the accumulation of particles. Overflow banks require a significant amount of water to maintain a minimum metal surface wetting rate. In addition, overflow banks require accurate leveling to maintain a uniform falling film that protects the metal in the cooling zone.

Of these problems, the most important is to directly associate the overflow wetting rate with the minimum wetting rate and the level of the device. These factors prevent minimizing the rate of water addition to the overflow bank, creating an unacceptable limit. No matter how much effort is put into leveling the cooling equipment, it has been found that due to the inherent thermal stresses involved during the combustion / cooling process, it is necessary to constantly relevel the device in order to maintain the cooling level within the tolerance range. This situation involves an unacceptable amount of maintenance effort. A discussion of the conditions necessary to minimize the rate of wetting and the level of the structure can be found in the Chemical Engineers Handbook (5th edition, pp. 5-57) by Perry & Chilton. You can find it. Also, Hewitt. See 'Process Heat Transfer' (CRC Press, pp. 539-541) by Hewitt, G.F. et al., And page 475 of the above reference for a detailed description of submerged cooling.

In the treatment of industrial waste streams, it is common to incorporate a cleaning device downstream of the process equipment (relative to the waste flow direction). The cleaning apparatus functions to receive and treat effluents generated during the upstream treatment operation.

For example, in the semiconductor manufacturing industry, several integrated cleaning devices are often used to treat effluents and barrier gases from commercially available and semiconducting manufacturing processes. Semiconductor manufacturing processes may include chemical vapor deposition, metal etching, etching and ion implantation operations. Examples of commercial integrated air scrubbers include the Delatech Controlled Decomposition Oxidizer, the Dunnschicht Analagen System Escape system, the Edwards Thermal Processing Unit, and the like. Each of these systems incorporates a wet cooling device to control the temperature of the effluent gas from the hot oxidation section, and a heat treatment unit to oxidatively decompose the effluent gases and to remove acid gases and particles found in the oxidation process. Wet purge system is included.

Purifiers, such as those used above, generally include an elongated column to receive effluents and to countercurrently contact these waters with a liquid solvent, reaction solution or slurry. Backflow contact results in intimate mixing, which assists the adsorption process to remove impurities from the effluent.

An integrated cleaning system can be installed in the manufacturing system to be an integral part of the manufacturing system. In contrast, a stand-alone system is maintained in the housing structure independent of the processing or manufacturing system. While this isolated unit can be integrated into the equipment of the upstream process, it is considerably more fluid than the counterpart of the integrated cleaning system.

The use of purge technology is not limited to integrated cleaning systems, but may also be incorporated into isolated operating systems. For example: a) stacked bed dry purifier that is not heated and chemically reacts, b) stacked bed dry purifier that is not heated and chemically absorbed, c) stacked bed dry purifier that is heated and chemically reacted, d) is heated and Catalyzed stacked bed dry purifiers, e) wet purifiers, f) flame heat treatment units, and the like. Each of these units can be applied for a selected use depending on the nature of the airflow during the treatment.

Purifier technology involves several drawbacks, including blockage of the inlet, line and manifold of the purifier. Partially clogged lines and / or manifolds thereby prevent the processing gas from flowing efficiently. Partially clogged lines or manifolds may interfere with the normal operation of the cleaning apparatus, such as the adsorption process that occurs with the decomposition of gaseous component (s) contained in the solvent medium.

In applications for purifying effluent airflow, several causes of obstruction have been suggested. The blockage can be caused by reaction with a silicon-containing injection component that reacts with water or water vapor, and can be caused by droplets containing silicon deposited at the inlet of the purifier. Such clogging mechanisms are applied to semiconductor tools used for epitaxial growth on a wafer and appear in processes using trichloro silane and dichloro silane. The blockage may also be caused by condensation of the condensable components in the inlet to the water purifier. The blockage may be caused by water vapor moving back from the water purifier to the inlet treatment line. The return moving water vapor can then react with the injection component to form a low volatility material and deposit at the water purifier side inlet. This last mechanism is characterized by decaying, for example, the purifier of the tool for metal etching treatment.

During metal etching machine operation, release gases such as BCl ₃ (boron trichloride) may be produced. Boron trichloride reacts with water vapor to form nonvolatile granular boric acid, which bores, condenses, accumulates and at least partially blocks the inlet or inlet lines.

In existing practice, several methods have been attempted to remove this type of blockage. One way is to periodically pour water through these obstructions. This adds a pressurized water stream to the blocked portion, which dissolves the blocked portion and ejects water. However, undesirably in such a jetting process, the return movement of the water now occurs at the injection point of the jetting water, increasing the hydrolysis reaction with water-sensitive gases such as WF ₆ (tungsten hexafluoride) upstream, It just moves the blockage further upstream.

Other methods use mechanical plunger mechanisms or other solid removal means to prevent solids from accumulating at the inlet and line. However, this mechanical solution is expensive, labor intensive, requires substantial maintenance and is prone to mechanical breakage.

The present invention relates to an inlet structure for injecting airflow into a downstream treatment equipment, such as a downstream gas treatment apparatus. In certain embodiments, the present invention relates to an anti-clogging inlet structure for injecting particulate solid-containing air streams and / or particulate solid-forming air streams into a gas treatment system.

1 is a schematic illustration of an anti-clogging inlet structure in accordance with an exemplary embodiment of the present invention;

FIG. 2 is a schematic view of a blockage preventing ingress structure according to another embodiment of the present invention; FIG.

3 is a schematic view of an anti-clogging inlet structure according to another embodiment of the present invention.

4 is a schematic view of an anti-clogging inlet structure according to another embodiment of the present invention.

5 schematically illustrates a gas / liquid interface structure in accordance with an exemplary embodiment of the present invention.

FIG. 6 is a plan view of the device of FIG. 5, showing a tangential feed device for liquid passing through the enclosed annular volume portion of the interface structure shown in FIG. 5; FIG.

7 shows (1) an upstream semiconductor manufacturing system; (2) manifold assembly; (3) A schematic illustration of a system including a downstream purifier unit.

8 is a schematic diagram of an exemplary embodiment of the present invention.

9 is a flow chart illustrating the steps of a cleaning cycle that may be executed in the example embodiment of FIG. 8.

In a broad aspect, the present invention relates to an inlet structure that injects an air stream, such as, for example, a particulate solid containing air stream and / or a solid forming air stream into a downstream processing unit, such as a gas treatment system, for example, It is constructed, arranged and operated to minimize negative hydrodynamic effects such as blockages (by solid deposits, air stream decomposition, etc.) and bypassing, short-circuiting of gas flow streams.

In one aspect, the inlet structure includes a gas permeable wall surrounding a gas flow path and an outer annular jacket surrounding the gas permeable wall and defining an annular gas reservoir therebetween. The outer annular jacket includes an annular solid containing air stream and / or a solid forming air stream while flowing into the gas treatment system through an inlet structure such as a port in a jacket for attaching a compressed gas supply vessel, such as a conventional compressed gas cylinder. Means for injecting gas into the gas reservoir are provided. In such an inlet structure, the gas supplied to the annular gas reservoir is compressed enough to exit through the gas permeable wall for the purpose of preventing solids from depositing or forming on the inner surface of the gas permeable wall.

In another variation, the inlet structure described above may optionally include a port for injecting pulsed higher pressure gas into the annular gas reservoir, the port being a high pressure gas source and the annular from the source. It is connected to a vehicle that pulses gas into a gas reservoir. In operation, such pulsing high pressure gas injection causes additional blockage resistance on the gas permeable wall, and even when low pressure gas is permeated through the wall, the inner surface of the gas permeable wall is caused by pulsatility. The particulate matter formed or deposited on the phase is removed. Ports in the outer annular jacket may be configured or arranged to allow tangential flow of high pressure gas into the annular reservoir.

As another variant of the inlet structure described above extensively, the gas permeable wall and outer annular jacket are optionally connected with downstream flow passage sections, the downstream flow passage sections defining corresponding other sections of the gas flow passage. It includes an enclosed, gas permeable wall and a wall forming a slot therebetween. The wall of the downstream flow passage section is surrounded by an outer annular jacket to define an annular liquid reservoir between the slot and the liquid overflow relationship therebetween, whereby an annular liquid reservoir is defined by the height of the wall. In the case of filling with water or other liquid above, the liquid extends down the wall portion along the inner surface of the wall portion in the form of a falling liquid film. Thus, the falling liquid film provides a shielding medium or a protective medium which prevents solids from depositing or forming on the inner surface of the wall, and also serves to wash off all the solids deposited or formed on the inner surface of the wall.

The outer annular jacket of the downstream flow passage section of the inlet structure may be provided with a port or other entry means, which may be a liquid such as a liquid containment vessel by a line or conduit or the like comprising a flow control valve or other flow control means. Connected to the source.

Port elements included in the above-mentioned structures may include a unitary opening, channel, connecting conduit, nipple, or other inlet structure and / or a plurality of said structures, for example in series in a vertical and / or circumferential direction to one another. There is an inlet structure, etc., through which in each case the fluid is transported to the contents of the annular reservoir associated with the port.

In another aspect, the inlet structure of the present invention includes a first flow passage section and a second flow passage section connected in series and generally perpendicular to each other, defining a flow passage that is generally vertical in this series connection relationship. A downstream flow treatment system disposed through the flow passage in such a way as to receive the inlet structure and the fluid flow from an upstream source of particulate solid containing and / or particulate solid forming airflow, or particulate solid containing fluid and / or solid forming fluid. Can flow towards

The first flow passage section is the top of the inlet structure and includes a gas permeable inner wall, which wall may be formed of a porous metal, porous ceramic, porous plastic, or other suitable constituent material, the first top of the flow passage section Surround. The porous inner wall has an inner surface that partitions the boundary above the flow passage.

The gas permeable wall is surrounded and surrounded by an outer wall spaced apart from the porous inner wall. The outer wall is not porous in nature, but the outer wall is provided with a gas flow port. By this arrangement, an annular inner portion is formed between each porous inner wall and the outer wall surrounding it.

The gas flow port may in turn be connected in flow relation to the gas source, allowing the gas to flow into the annular volume, for example at a predetermined low flow rate by suitable valves and control means, and then the gas into the annular volume portion. Flow from the flow path. In addition, a high pressure gas flow port is provided on the outer wall of the first flow passage section and is connected in flow relationship with the high pressure gas source to cause the gas to flow intermittently into the annular volume portion, which high pressure gas flow is the porous inner wall (first Removing particulate matter from its inner wall which may be deposited on the flow passage section in the flow passage section). Likewise, the high pressure gas can be controlled to flow to the desired pressure by suitable valves and regulating means.

The second flow passage section is connected in series with the first flow passage section to allow particulate solid containing fluid to flow from the first flow passage section to the second flow passage section downstream. The outer wall of the second flow passage section is provided with a liquid injection port, which port is connected to a liquid source, such as water or other processing liquid. The outer wall is connected to the first flow passage section by a flap flange or the like on each outer wall of the first flow passage section and the second flow passage section. The second flow passage section includes an inner weir wall spaced from the outer wall, and defines an annular content therebetween, the inner weir wall extending toward the porous inner wall of the first flow passage section and the wall. Terminated in the vicinity, a gap is provided between each inner wall of the first flow passage section and the second flow passage section defining the dam wall. When liquid flows into the annular content between the outer wall of the second flow passage section and its inner wall, the injected liquid overflows the dam and flows along the inner surface of the inner wall of the second flow passage section. This liquid flow down the inner wall washes away the particulate solid from the wall and inhibits the deposition or formation of solid on the inner surface of the inner wall.

The flanged connection of the first flow passage section and the second flow passage section may include a clamp assembly that can be quickly released, which facilitates the first flow passage section and the second flow passage section of the inlet structure. Allow disassembly.

In addition, the first flow passage section of the inlet structure can be connected with the top quick release inlet section of the inlet structure, which likewise can be easily disassembled for cleaning and maintenance.

In another aspect, the present invention relates to an airflow receiving structure capable of preventing depositing, clogging and corrosion of solids when a high temperature particle accumulation-containing airflow containing a corrosion component flows. More specifically, this aspect of the invention relates to a gas / liquid interfacial structure useful for transporting hot, particulate solid-containing gas flowing from an upstream gas source to a downstream processing unit.

Such a gas / liquid interface structure is a first flow passage member extending in a vertical direction defining a first air flow passage therein, the upper inlet through which air flow is introduced into the air flow passage, and a gas flow passage in the inlet flow passage member. A first flow passage member having a lower outlet end for discharging airflow subsequent to the airflow flowing through the airflow; A second flow passage member that surrounds the first flow passage member to be spaced outwardly so that an annular volume is formed therebetween, the lower outlet end of which extends downwardly below the lower outlet end of the first flow passage member, A second flow passage member having a lower liquid impermeable portion and an upper liquid permeable portion defining an air flow flow passage of the second flow passage member; An outer wall member enclosing the second flow passage member and defining an annular inner portion with the second flow passage member; A liquid flow inlet port of the outer wall member for injecting liquid into the annular volume between the outer wall member and the second flow passage member, whereby the fluid injected through the liquid flow inlet port of the outer wall member is surrounded Enters and exudes through the upper liquid permeable portion of the second flow passage member, and then flows down along the inner surface of the liquid impermeable portion of the second flow passage member to flow into the inner surface of the liquid impermeable portion of the second flow passage member. Providing a liquid film flowing downward in the bed prevents particulate solids from depositing or accumulating thereon, and airflow flowing through the first flow passage member is discharged from its lower outlet end and flows through the flow passage of the second flow passage member. And then released from the gas / fluid interface structure.

By this arrangement, the airflow is prevented from directly contacting the lower wall of the inlet structure, and the airflow flow passage is defined by the wall inner surface of the second flow passage member. The water film flowing down from the 'weeping weir' above the second flow passage member prevents particulate solids from accumulating on the wall surface of the second flow passage member. The flowing liquid airflow on the wall transports particles of the airflow in contact with the water film downwards and releases them from the gas / liquid interface structure. In addition, corrosive components in the airflow are prevented from contacting the wall, which is protected by a water film flowing down from the bottom of the interface structure.

In another specific embodiment, the present invention is disposed between an upstream oxidation unit, such as an electrothermal oxidation unit, and a downstream water purifier that purifies the gas with water to remove particulate solids contained in the gas.

The upper liquid permeable portion of the second flow passage member may consist of a suitable porosity, for example comprising a porous sintered metal, a porous plastic, or a porous ceramic wall, wherein the pore size is, for example, about 0.5 To about 30 microns, and may be larger.

In another aspect of the present invention, the present invention relates to an apparatus and method for purifying an inlet line of a manifold that transports gas to a purge unit, in the case of a process unit downstream of a process unit, e. It is about.

The purifier includes a manifold that receives gas from an upstream source, such as a semiconductor manufacturing process system or tool. The manifold includes a first inlet line and a second inlet line that are alternately used to flow the gas to a downstream process. These lines are connected to the manifold conduit at its first (upstream) end, and each of the first inlet line and the second inlet line may comprise, for example, a purification unit at its second (downstream) end. Is connected to the processing unit in a flow communication relationship.

Each of the first inlet line and the second inlet line includes therein a pneumatic valve, which can be selectively opened and closed, respectively, for example to flow and interrupt the gas.

The manifold is arranged to receive gas from an upstream source and to flow gas through the manifold and the first inlet line or the second inlet line, one of which lines actively flow gas from the upstream source to the downstream processing unit. And the other inlet line shuts off the flow of gas through the line by closing the valve therein.

A pressurized water source is connected to the manifold by a water flow line connected to the first inlet line and the second inlet line. Each water flow line includes, for example, a pneumatic valve. Each valve can be selectively opened and closed to allow pressurized water to flow or intervene therethrough.

In order to selectively raise the temperature of at least one inlet line of the two inlet lines, for example, each of the first inlet line and the second by a thermal jacket disposed near each of the first inlet line and the second inlet line. A heat source can be connected to the inlet line.

In operation, gas from the upstream processing unit flows into the manifold. During active processing, the valve of either the first inlet line or the second inlet line is open and the valves of the other inlet line are closed so that gas entering the manifold flows through a specific inlet line including an open valve. . In this way, the gas flows through a particular inlet line that includes an open valve and passes through the downstream processing unit. The inlet line comprising the open valve is referred to below as the 'open inlet line' for the sake of simplicity, and the remaining line of the manifold is referred to as the 'off-stream line'. In the flow shutoff line, the valve is closed to prevent gas from flowing through it.

The valve in the inlet line can be operatively integrated and controlled by suitable cycle timer means and control means in conventional conventional form, as employed in the apparatus of the present invention.

The flow shutoff line, which does not flow gas, is purged to regenerate gas for further processing. Thus, in the case of continuous operation of the apparatus, the valves in each inlet line will open one of these valves at a given time and the other to purge the flow shutoff line, and then open the line for flow on-stream operation. It is controlled to be closed for updating.

The flow shutoff line is cleaned by opening the valve in the water flow line that communicates the pressurized water source with the flow shutoff line, thereby allowing pressurized water to be injected from the pressurized water source to the flow shutoff line. In another water line, the water line valve is closed to prevent pressurized water from flowing from the pressurized water source to the flow connection line.

In this way, the flow interruption line, which is empty due to isolation, is actively cleaned by various cleaning operations, including pressurized water washing and the like.

Optionally, a pressurized dry gas source is connected to the manifold by a dry gas flow line that is connected to each of the first inlet line and the second inlet line. Each dry gas flow line includes, for example, a pneumatic valve. Each valve can be selectively opened and closed to allow pressurized dry gas to flow or intervene therethrough.

After the pressurized water flows through the flow shutoff line, the flow shutoff line can subsequently be dried to prepare fresh gas to flow from the upstream source to the downstream treatment unit. This is done by closing the valve in the pressurized water flow line to stop the pressurized water jetting / purging action on the water at the surface of the flow interrupting line. At the same time, the valve in the dry gas flow line in communication with the flow shutoff line is opened to allow compressed dry gas to be injected through the valve into the flow shutoff line and to dry the inner surface of the flow shutoff line, so that the jet water is manifolded. Is completely removed from the flow blocking line. In this way, the flow shutoff line becomes full when the process gas flow through the cleaned and dried line is resumed, i.e. when the flow shutoff line is back to the flow connection line and the previous flow connection line is in the flow shutoff line state. It may be completely dried to avoid hydrolysis reactions in subsequent work of the system.

This continuous conversion operation involves first opening the valve in the flow shutoff line so that the process gas can subsequently flow through the valve. Once the valve in the flow shutoff line is changed to open, the valve in the dry gas line is closed. This process prevents the valve from closing and the occurrence of a return flow of the upstream treatment flow.

In this way, the manifold gas treatment system is operated such that gas flows from the upstream source through the inlet line through the downstream treatment unit, where the gas flows continuously through each inlet line alternately, During the flow interruption period of the line, the line is spouted with pressurized water and optionally and preferably dried by flow through the inlet line of the compressed drying gas, which subsequently causes the inlet line to flow through the inlet line. Update.

Water from the pressurized water jet step and the compressed gas drying step can flow through the flow block inlet line and be discharged into the water purifier or from the flow block line through a valved discharge line for this purpose. In the treatment of semiconductor production exhaust gas by downstream purification, it is usually advantageous to discharge the jetted water and the compressed dry gas into the downstream purifier.

The first inlet line and the second inlet line may be provided with associated heating means such as electric resistance heaters, stream tracing lines, heating jackets, etc., by which the drying process can be carried out faster, Otherwise heat is provided to the process to facilitate cleaning of the inlet line of the manifold.

In a method aspect, the invention relates to a method of flowing gas from an upstream source through a manifold comprising two inlet lines through which gas flows, wherein (a) one of the inlet lines is a flow Flowing said gas through a flow connection inlet line of said two inlet lines when said inlet line is an inlet line that is isolated for gas flow from an upstream source to a downstream processing unit; (b) ejecting the isolated inlet line with pressurized water to remove particulate solids, water soluble solids, and the like from the inner surface of the isolated inlet line; (c) regulating the flow of pressurized water through the isolated inlet line; (d) optionally, flowing compressed dry gas through the isolated inlet line to dry the inner surface of the isolated inlet line; (e) regulating the flow of compressed dry gas through the isolated inlet line; (f) isolating said isolated inlet line to constitute a flow connection inlet line; (g) intercepting the flow of gas through the flow connection inlet line and isolating the flow connection inlet line to form an isolated flow blockage inlet line; (h) reflowing the gas through a flow connection inlet line isolated from an upstream source to a downstream processing unit, performing steps (a) to (h) periodically, alternately and repeatedly, During gas flow from the upstream source to the downstream treatment unit, one of the inlet lines contains gas from the upstream source that flows through it and the other line is in flow shutoff, and the high pressure water jet and drying are optionally carried out. It is done.

The treatment as described above may optionally be performed by heating the inlet lines.

Other aspects, features and embodiments of the invention will be more clearly understood from the following description and claims.

Referring to the drawings, FIG. 1 is a schematic illustration of an anti-clogging inlet structure in accordance with an exemplary embodiment of the present invention.

The inlet structure shown in FIG. 1 may be connected to a process piping connecting the inlet structure with the airflow source injected into such a structure. This upstream treatment tubing may be appropriately heat-tracing in a conventional manner from an upstream airflow source, such as a semiconductor manufacturing tool, to the inlet flange of the inlet structure as shown. The purpose of such heat trace treatment is to provide sufficient energy to the airflow in the piping so that some components in the airflow do not condense or sublimate in the inlet structure.

The inlet structure 60 shown in FIG. 1 comprises an inlet section 7 with an inlet flange 16. The inlet flange can correspondingly engage the flange 18 of the upper annular section 8 in which the upper end is terminated. The inlet section may be connected to an upstream particulate solid containing and / or particulate solids forming airflow generation facility 90, such as, for example, a semiconductor manufacturing tool.

The annular section 8 has a porous inner wall 6 having an appropriate porosity of gas permeability and a rigid outer wall 9 forming an annular inner portion 20 therebetween. Thus, the inner surface of the porous inner wall 6 defines a flow passage 66 in the upper annular section 8. The upper and lower ends of the rigid outer wall 9 are surrounded by the end walls 40, 42 with respect to the inner wall 6 to surround the annular contents. A gas inlet port 22 is provided on the outer wall 9, and a gas supply line 24 is connected to the port. The gas supply line 24 is connected at its outer end to the gas source 4. The gas supply line 24 is arranged with a check valve 14 to regulate the airflow flowing into the annular inner portion 20. The gas supply line 24 may be provided with other flow control means (not shown) to selectively supply gas from the gas source 4 to the annular volume 20 at the required amount and flow rate during operation of the system.

Means for heating the gas supply line 24 may be included to raise the temperature of the gas passing through the porous inner wall 6. The heating means of the gas supply line 24 are known to electric resistance heaters, heat trace processing lines, heating jackets or those skilled in the art and are useful for transferring thermal energy to the internal passages of the gas supply line 24 to raise the temperature of the gas. Other heating systems. For example, the heating means employed in the embodiment of FIG. 1 consists of a heating coil 23. In addition, a heat jacket can cooperate with the heating means to raise the internal temperature of the gas supply line 24.

The upper annular section 8 may optionally have a high pressure gas injection port 50, which is connected to a high pressure gas supply line 52, which in turn is connected to the high pressure gas source 5. Connected. The gas supply line is shown with a built in flow control valve 51, which can be connected to flow controller means (not shown) that operates the valve in a predetermined order. Optionally, the high pressure gas supply line 52 may be arranged at an appropriate angle, such as an inclined angle, with respect to the high pressure gas injection port 50.

Although the optional high pressure gas injection port 50 and the high pressure gas supply line 52 may be flowed (or extracted) at a constant flow rate, even though the low pressure gas injected into the annular volume portion 20 from the gas supply line 24, It is beneficial if accumulation of solids occurs on the inner surface of the gas permeable wall. Means for heating the high pressure gas supply line 52 may be provided and included to raise the temperature of the gas in that line. Such gas supply line 52 heating means are known to electric resistance heaters, flow tracking lines, heating jackets or those skilled in the art and are useful for transferring thermal energy to the internal passages of gas supply line 52 to raise the temperature of the gas. Other heating systems. For example, the heating means employed in the embodiment of FIG. 1 consists of a heating coil 54. In addition, a heat jacket can cooperate with the heating means to raise the internal temperature of the gas supply line 52.

The upper annular section 8 has its lower end terminated at the flange 26, which engages in a corresponding relationship with the flange 28 of the lower annular section 30. These flanges 26, 28 may be sealed by a sealing means such as the O-ring 10 shown in FIG. 1.

The lower annular section 30 includes an outer wall 12 whose upper end terminates at the flange 28. The outer wall is a type of jacket member whose lower end is joined to the inner weir wall 11 by an end wall 44, forming an annular inner portion 32 between the outer wall 12 and the inner weir wall 11. . The inner weir wall 11 extends vertically upward as shown, but terminates with its upper end 46 spaced apart from the lower end of the porous inner wall 6 of the upper annular section 8. A gap 36 is formed between the lower end of the upper end and the upper end of the inner weir wall to form an overflow wed for the lower annular section 30.

The outer wall 12 of the lower annular section 30 is provided with a water inlet port 48, which is connected to a water supply line 80 incorporating a liquid flow control valve 81 and connected to the water source 3. The liquid flow control valve is operatively coupled with other flow control means to maintain the flow rate of liquid flowing into the lower annular section 30 to the required degree. The water inlet port 48 may be fixed to the lower annular section 30 in the radial or tangential direction. In a preferred embodiment of the invention the water inlet port 48 is fixed tangentially to the lower annular section 30 so that the moment of the water jet injected into the lower annular section does not proceed against the fixed wall, The overflowing water in the lower annular section swirls tangentially so that it dissipates itself. At this time, by injecting water in the tangential direction, the moment above the water film is disturbed to optimize the height of the water film flowing over the lower annular section.

An elongate air flow conduit 70 may be used to inject the particulate solid containing air stream and / or the particulate solid forming air stream to a specific location of the inlet structure. The delivery conduit 70 is connected to the upstream airflow source 90 in accommodating the airflow, and propagates and exhausts the airflow to an appropriate position in the internal gas flow passage 66 to minimize the formation of solids in the inlet structure. . The conduit 70 is surrounded by an inlet section 7 and a rigid outer wall 9 modified to receive the conduit 70. The delivery pipe 70 may be heated to prevent condensation of the airflow flowing through the delivery pipe 70.

In the inlet structure shown in FIG. 1, the delivery conduit 70 is surrounded by a porous inner wall 6 and concentric with the porous inner wall 6. The outer surface of the delivery pipe 70 and the inner surface of the porous inner wall 6 form an annular volume therebetween. The air flow conduit 70 includes a first end 72 connected to an airflow source 90 in an airflow receiving relationship, and a second end 74 for discharging airflow in the airflow passage 66. The second end 74 discharges airflow in the airflow passage 66 provided in the upper annular section 8 or the lower annular section 30. In the illustrated embodiment, the delivery conduit 70 is venting airflow about half an inch below the upper end 46 of the internal weir wall, while the delivery conduit 70 is based on the airflow, process usage, and conditions. It may extend further below the top 46 of or end above the top 46 of the inner weir wall.

The delivery conduit 70 can be formed, for example, with an internal diameter of about 0.5 to 4 inches using stainless steel. Those skilled in the art will appreciate that the delivery conduit 70 can be constructed in a variety of materials, sizes, cross sections and shapes. The common annular flow pattern generated by placing the delivery conduit 70 relative to the porous inner wall 6 and the overflow embankment wall 11 is treated when the processing gas exits the delivery conduit and enters the flow passage 66 region. It serves to minimize gas mixing with water vapor coming from the inner weir wall (11). Therefore, the solid formation reaction between the processing gas exiting the delivery pipe 70 and the water vapor coming from the inner weir wall 11 is greatly reduced to the downstream position, so that the solids are reduced downstream by the action of the inner weir wall 11. May be ejected into the appliance.

In order to determine the anti-clogging efficacy of a given inlet structure within the scope of the present invention, as an appropriate judgment technique, the nitrogen carrier gas at an average flow rate and trichlorosilane at a flow rate of 1-5 slpm are subjected to a specific position and solid of the inlet structure after a few minutes. By monitoring the amount of formation, the suitability of the structure and the influence on the change of a predetermined parameter in the inlet structure is determined. Longer observation periods may be required to monitor solid growth properties. Also, depending on the air flow, process use and conditions, by maintaining the axial laminar flow in the annular section between the gas delivery line and the outer surface of the gas delivery line and the inner surface of the porous wall, appropriate maintenance of the inlet structure wall and discharge flow Hin protection is guaranteed.

The delivery conduit 70 may also be heated to reduce condensation of the gas. Solids form on the walls of the delivery conduit 70 by condensation of gas flowing through the delivery conduit. Suitable means for heating the conduit 70 may include an electrical resistance heater, an air flow trace line, a heating jacket, and the like, wherein the heating system is configured to deliver thermal energy to the internal passageway of the conduit 70 to prevent condensation. And arranged. For example, the heating means is shown with a heating coil 76. In addition, the heating jacket may cooperate with the heating means to increase the internal temperature of the delivery pipe 70. The heating jacket may be employed to raise the temperature of the sidewalls to prevent condensable process gases from condensing in the conduit.

The lower annular section 30 can be suitably connected to the housing of the water purifier 13 at the bottom. The water purifier may be configured in a conventional manner to clean and remove particles and dissolved components in the process air stream. Optionally, the inlet structure 60 may be connected to another processing facility for the treatment of airflow passing the inlet structure from the inlet end to the outlet end.

Thus, the inlet structure 60 has a gas flow passage 66 which is a passage through which the inlet gas can flow from the direction indicated by arrow '1' in FIG. 1 to the discharge end in the direction indicated by arrow '2' in FIG. Is provided.

In operation, the particulate solid-containing gas is injected from an upstream source, such as a semiconductor manufacturing tool (not shown), by appropriate connection piping, which has been described above to prevent harmful sublimation or adhesion of airflow components within the inlet structure. To be heat traced. The airflow enters the inlet structure in the flow direction indicated by the arrow '1' and passes through the inlet section 7 (or, if installed, the conveying pipe 70) to the upper annular section 8. Gas or other gas, such as nitrogen, flows out of the gas source 4 and enters the annular volume 20 through a gas supply line 24 connected to the gas inlet port 22. From this annular inner portion 20 the injection gas flows through the gas permeable inner wall 6 into the internal gas flow passage 66. Thus, when the granular containing or particulate forming gas flows from the gas supply line 24 through the gas permeable inner wall 6 into the annular inner volume 20, into the water purifier 13 through the inner gas flow passage 66. Flow.

In this way, the annular inner portion 20 is pressurized by the gas coming from the gas source 4. The pressure at this time ensures that the gas is constantly steady flowing into the inner gas flow passage 66 through the porous inner wall. Such a slow, steady flow of gas through the gas permeable inner wall keeps particles of airflow flowing through the inner gas flow passage 66 away from the inner wall inner surface of the inlet structure. In addition, any gas present with the airflow in the inner flow passage 66 also keeps away from the inner wall inner surface of the inlet structure.

Gas supply line 24 may be heat traced if desired. Such heat trace treatment may be desirable when the airflow flowing through the inlet structure contains species that can condense or sublimate and deposit on the walls of the inlet structure.

At the same time, high pressure gas can be periodically flowed from the high pressure gas source 5 through the high pressure gas supply line 52 and the high pressure gas injection port 50 to the annular inner volume 20. For example, the gas supply line 52 has a built-in flow control valve (not shown) to accommodate the high pressure gas injected into the pulse. In this way, the high pressure gas is injected into the annular volume at certain predetermined intervals to remove any particles formed on the inner surface of the gas permeable inner wall 6. The period and time sequence in which the high pressure gas is pulsed and injected can be readily determined by those skilled in the art without undue experimentation, achieving the desired wall cleaning effect of preventing the accumulation of solids on the gas permeable wall. If necessary, when the inlet structure is employed in connection with a water purifier for grooming the semiconductor manufacturing tool, such high pressure spraying can provide adequate pressure control at the semiconductor manufacturing tool outlet port by integrating control means operatively connected to the semiconductor manufacturing tool control system. It can be interrupted during one processing cycle of the semiconductor manufacturing tool so as not to occur. For this purpose, a control valve, such as a solenoid valve, can be properly connected with the control means of the semiconductor manufacturing tool assembly.

In the inlet structure of the illustrated embodiment, the flanges 26, 28 can be interlocked so that the upper annular section 8 can be quickly separated from the lower annular section 30. For that purpose, quick disconnect fastening can be used. The sealing gasket between the flanges 26, 28, or the O-ring 10 may be formed of a suitable material, such as a corrosion resistant high temperature elastomeric material. Such elastomeric gaskets also function as a thermal barrier to minimize the transfer of heat from the upper annular section of the inlet structure to the lower annular section, which is a particularly important feature in the heat traced embodiment of the present invention.

The gas permeable inner wall 6 of the upper annular section of the inlet structure may be formed of a suitable gas permeable material such as ceramics, metals, alloys and plastics. As a specific example, the gas permeable inner wall may be formed of Hastelloy 276 material. The outer wall 9 of the upper annular section can likewise be formed of a suitable material, for example a thin walled stainless steel pipe.

The lower annular section 30 of the inlet structure may be formed of a suitable material such as polyvinylchloride plastic. Water is sprayed from the water source 3 through the water supply line 80 to the annular inner portion 32 between the outer wall 12 and the inner weir wall 11. Preferably, the water is sprayed in a tangential direction such that the water moves at an angle within the annular inner portion 32, such that the upper end 46 of the inner weir wall 11 in the inner flow passage 66 of the inlet structure. Spiralized above and below its inner dam wall. Thus, water flows below the inner surface of the dam wall 11, and the predetermined particle | grains are wash | cleaned below the flow path 66 to the water purifier 13 below the inlet structure. As mentioned above, the lower annular section 30 is an optional structural feature that may be omitted, for example if the downstream processing unit is a combustion purifier.

The pressure drop in the inlet structure can be easily determined by tapping the pressures of the upstream processing unit of the inlet structure and the discharge piping of the downstream purifier unit. This pressure drop can be detected with a Photohelic gauge or other suitable pressure detection gauge, and such pressure drop readings can be sent to a suitable monitor and control facility that monitors for blockage of the purifier inlet.

By using the inlet structure according to the invention, an interface can be provided between the semiconductor manufacturing tool discharge and the water purifier from the semiconductor manufacturing operation, which is not repeatedly blocked during normal operation. The inlet structure of the present invention provides an interface with two auxiliary processing air streams, a low speed purge stationary stream and a high pressure pulse air stream. The low speed purge air stream forms a total flow rate of inert gas, such as nitrogen, flowing from the inner surface of the upper annular section toward the centerline of the central flow passage 66. High pressure airflow provides self cleaning capability to prevent solid blockages. Using high pressure airflow, no particles are formed on the inner surface of the upper annular section of the central flow passage 66 of the inlet structure.

The gas, companion particles and previously deposited particles are then guided to the overflow air stream at the inner surface of the lower annular section of the inlet structure and blown down into the water purifier downstream of the inlet structure. In this way, the direct interface between the gas permeable wall of the upper annular section of the inlet structure and the inner weir wall of the lower annular section forms a high efficiency inlet structure that effectively minimizes the formation of particulate solids during operation.

The inlet structure according to the invention has a number of advantages. In the application for a semiconductor manufacturing facility and a water purifier treatment system for processing wastewater discharged from a semiconductor manufacturing tool of a semiconductor processing facility, the gas discharged from the semiconductor manufacturing tool is the water of the water purifier inlet structure from the semiconductor manufacturing tool discharge port. It can be heated continuously all the way to the interface. Heat trace treatment may be performed on the inlet line to transfer energy to the piping to heat the inlet line, which delivers the energy to the flow airflow by forced convection. The process gas is subjected to heat tracing treatment of the air flow line flowing gas into the upper annular section and heat trace treatment of the high pressure air flow line supplying the pulsed high pressure gas to the annular volume of the upper annular section of the inlet structure. It can be heated all the way down to the overflow dam wall of the annular section. This heated gas flow maintains the process gas that continues to flow through the central flow passage of the inlet structure at a temperature measured by the vapor pressure of the desired particulate forming gas in the air stream flowing from the upstream processing unit to the inlet structure; In this case, the gas condenses or sublimes and deposits on the inner wall of the inlet structure.

Another advantage of the inlet structure of the present invention is that it can be easily disassembled. If the inlet structure is clogged during operation, the inlet structure is easily disassembled by simply separating the clamp or other fastening element that holds the flanges of the structure together. Thus, it is possible to replace the upper annular section by removing the clamps that hold each flange in place and separating each gas supply line connected to the upper annular section.

Another advantage of the inlet structure according to the invention is its self cleaning properties. Particles entrained in the airflow flowing from the upstream processing unit to the inlet structure, or formed by chemical reactions in the inlet structure, are injected into the annular volume portion in the upper annular section of the inlet structure by injecting high pressure gas which is pulsed into the annular structure It can be easily cleaned from the gas permeable inner wall. Subsequently, particles falling off the inner surface of the upper annular section of the inlet structure are directed to the overflow of the inner weir wall where such particulate solids are ejected to the downstream purifier. The pressure, duration and periodicity of the pulsed high pressure gas can be easily set to accommodate the key conditions of the system particle concentration and the properties of such solids. The injection efficiency of the pulsed high pressure gas depends on the characteristics of the particulate solid. Thus, the inlet structure of the present invention has self-cleaning properties without the use of a scraper or plunger device, a so-called self-cleaning device commonly used in prior art fluid treatment systems.

The material properties of the porous inner wall of the upper annular section of the inlet structure depend on the processing gas entering from the upstream processing unit. If the air flow contains an acidic gas component, such gas will be absorbed in the water purifier and present in the water that is recycled to the overflow bank wall in the lower annular section of the inlet structure. Some of the water in the overflow bank wall may be ejected to the porous inner wall of the upper annular section of the inlet structure. In that case, the porous wall is preferably selected as the corrosion resistant constituent material. A preferred metal material for this purpose is Hastelloy 276 steel, which exhibits excellent corrosion resistance even under low temperature hydrous acid conditions.

Another advantage of the inlet structure of the present invention is that the backflow of water vapor from the top of the water purifier into the treatment piping is minimized when the inlet structure is used upstream of the water purifier as illustrated herein. By describing this advantage, it will be appreciated that the particles may be present during the discharge flow of some semiconductor manufacturing tools, as particles entrained from the processing tool, or as reactants of chemical reactions in the flow path of the air stream.

The present invention minimizes or eliminates the aforementioned Richardson annular effect. As gas normally flows out of the inner surface of the porous inner wall of the upper annular section of the inlet structure, static boundary layer conditions cannot develop at the inner surface of the upper annular section. The total flow rate of gas flowing out of the gas permeable wall acts to 'push' the treatment air flow out of the wall surrounding the central flow passage of the inlet structure and eliminate the Richardson annular effect by the absence of static boundary conditions. Thus, when the particles are formed as a result of chemical reactions in the air stream, the particles thus formed do not aggregate on the walls. Instead, the particles will flow with the air stream into the water purifier. The same is true for the entrained particles. Once the particles reach the top of the inlet structure, these particles will be entrained in the air stream because they have no walls to aggregate.

By retarding the conditions causing the Richardson annular effect, the porous inner wall in the upper annular section of the inlet structure of the present invention acts as an effective barrier to prevent back migration of water vapor to the discharge line of the treatment system. Any reverse movement will be extremely slow due to the interdiffusion mechanism described above. This factor greatly reduces the average downtime of the purifier, since the purifier inlet and outlet lines are not frequently blocked in the case of the inlet structure of the present invention. When the delivery conduit 70 is used, the reverse movement of water vapor is minimized or eliminated due to the annular gas blanket formed by the flow of gas through the porous inner wall 6.

Although the porous inner wall member of the upper annular section of the inlet structure of the present invention has been described herein as being composed of a metallic material, it will be understood that such gas permeable inner wall may be formed of any suitable component material. For example, the porous inner wall may be subjected to corrosive environments, extreme temperatures and input pressures that may be present when using porous ceramics, plastics (eg, porous polyethylene, polypropylene, polytetrafluoroethylene, etc.), or inlet structures of the present invention. It may be formed of another material having the ability to withstand it.

Although the present invention has been described with respect to the embodiments herein shown in FIG. 1, each has an upper annular section and a lower annular section interconnected by flanges and associated quick disconnect clamps or other interconnecting means. Such inlet structures may be formed as monolithic or monolithic structures if desired or necessary for a given end use application of the present invention, and the lower annular section is an optional section for the upper annular section and may be unnecessary in some cases.

Referring to FIG. 2, another embodiment of the anti-clogging inlet structure is shown. The inlet structure 100 may optionally include a conical skirt 105 surrounded by a rigid outer wall 110. An annular gas flow passage 115 is formed between the outer surface of the delivery pipe 112 and the inner surface of the conical skirt 105. The conical skirt annularly surrounds the particulate solid-containing and / or particulate solid-forming airflow with an inert gas and / or liquid. Inert gas enters the inlet structure via supply line 120. The conical skirt that opens outwards is designed to gradually decrease in cross-sectional area, thereby increasing the speed of the inert gas and decreasing the pressure. The conical skirt 105 is designed such that the velocity of the airflow discharged from the delivery pipe 112 and the velocity of the inert gas are the same. This matching of the flow rates of the inert gas and the airflow creates an equivalent co-laminar flow to prevent the formation of turbulent flow in the airflow and to prevent mutual mixing at the interface between the two flow streams. It is advantageous to Thus, the efficiency of this inlet structure is improved by minimizing the accumulation of particulate solids during operation.

Conical skirts that spread outwards may also be advantageously used to inject liquid into the inlet structure. The outer wall 110 and the lower end (bottom circumference) of the conical skirt are spaced apart from each other in the transverse direction, forming a liquid flow passage 135 therebetween. Spray nozzles 125 may be spaced apart in the circumferential direction with respect to each other in the inlet structure to disperse the liquid. The conical skirt guides the liquid towards the wall surface 130. For example, if the liquid is water, a thin film of water is formed on the wall surface 130 to eject the particulate solid to the downstream purifier. The material properties of the conical skirt depend on the inert gas and the airflow flowing through the delivery conduit 112. If the air stream contains an acidic gas component, this gas is present in the water recycled to the spray nozzle 125. The conical skirt of this example is preferably made of a corrosion resistant material. As described with reference to the embodiment of FIG. 1, the delivery conduit, inert gas and / or water may be heated to reduce condensation.

3, another embodiment of the anti-clogging inlet structure 200 is shown. The rigid outer wall 205 and the porous inner wall 210 form an annular content therebetween. An elongate air flow conduit 2121 may be used to inject the particulate solid-containing and / or particulate solid-forming airflow into a particular predetermined location of the inlet structure. The delivery conduit 212 is coupled to the upstream source in a gas flow receiving relationship to direct and discharge the airflow to a suitable location within the inlet structure. The inner surface of the porous inner wall 210 wraps around the outer surface of the delivery tube 212. The upper end of the outer wall 205 is surrounded by the end cap 215.

The outer wall is provided with a water inlet port 225 that may be connected to a water source. The end cap 215 is provided with a gas inlet port 230 to axially inject a protective inert gas into the inlet structure. End cap 215 may optionally include a porous disperser structure that axially disperses inert gas into the inlet structure. Optionally, a gas cavity or reservoir may contain an inert gas, such as nitrogen, which is injected into the inlet device. In this embodiment, water is blown out through the porous inner wall 210 to form a liquid film, which passes through the inlet structure to eject particles. Porous wall 210 may be formed of a suitable material, such as, for example, ceramic, metal, alloy, or plastic, such as polyvinylchloride. As mentioned above, the delivery tube, inert gas and / or water may be heated to reduce or eliminate condensation.

As another variation of the particular structure shown in FIG. 3, the porous inner wall 210 may be replaced with a weir wall of the type shown in FIG. 1. For example, the dam wall may be configured to be spaced relative to the end cap such that a gap is formed between the top end and the top end cap 215 to form an overflow bank.

4 shows another embodiment of the anti-clogging inlet structure 300. The upper annular section 305 includes an upper porous inner wall 310 and an upper rigid outer wall 315, forming an upper annular inner chamber 320 therebetween. The long air flow tube 322 is shown surrounded by an upper porous inner wall 310 and is disposed coaxially with the porous inner wall 310. The outer surface of the gas delivery pipe and the inner surface of the upper porous inner wall form an annular volume therebetween. The delivery pipe 332 is coupled in a gas flow receiving relationship with an upstream gas source. The upper rigid outer wall 315 includes an inlet port 325 that injects suitable fluid into the upper inner chamber 320.

The lower annular section 330 includes a lower porous inner wall 335 and a lower rigid outer wall 340, forming a lower annular inner chamber 345 therebetween. The bottom rigid outer wall includes an inlet port 350 that injects fluid into the lower chamber 345. In operation, the inlet structure of FIG. 4 allows inert gas to penetrate through the upper porous inner wall 310 and allow water to be pumped out through the lower porous inner wall 335. This flow of inert gas keeps particles in the airflow away from the inner wall inner surface of the inlet structure. The thin water film on the inner surface of the lower porous inner wall 335 washes away any particles from the inlet structure.

4 shows a delivery conduit 322 that releases airflow above the transition region 355 between the upper section 305 and the lower section 330. The transition region 355 is a region where the upper annular section 305 and the lower annular section 330 are in contact with each other. The transition region 355 may also include an area separating the lower section 330 and the upper section 305 and surrounding the gas delivery pipe 322. It will be appreciated that the conduit may optionally extend to the lower section below the transition region 355. Whether the delivery conduit 322 emits airflow in the upper section, in the transition zone, or in the lower section depends on the airflow, process use and conditions. As mentioned above, the delivery tube, inert gas and / or water may be heated to reduce or eliminate condensation.

5 is a schematic cross-sectional view of a gas / liquid interface structure 410 in accordance with one embodiment of the present invention.

The gas / liquid interface structure 410 includes a vertically extending first flow passage member 412 formed by the elongated cylindrical wall 414. The cylindrical wall 414 surrounds the inlet passage 418 in the flow passage member 412. At the top of the cylindrical wall 414 is a flange 416 extending radially outwardly to couple the gas / liquid interface structure to flow piping, conduits, fixtures, and the like in related processes.

Accordingly, the first flow passage member 412 has an inlet 420 at its upper end and a corresponding outlet 422 at its lower end, so that the open inlet end and the outlet end are flow paths including the flow passage 418. In this case, the gas supplied from the upstream processing unit 458 may be flowed as illustrated by line 460 in FIG. 5 through this flow path.

The length of the first flow passage member 412 may be significantly shorter than that shown in FIG. 5, with the distal outlet 422 of this flow passage member being the top wall of the annular interior portion 430 of the gas / liquid interface structure. (438) may be terminated just below. Optionally, the distal outlet 422 of this flow passage member may terminate in a second flow passage member 424 at a point below the vertical direction than illustratively shown in FIG. 5.

Accordingly, the downward vertical range of the first flow passage member 412 may vary in accordance with the practice of the present invention, and certain length and dimensional characteristics may be configured and arranged to achieve the operating characteristics required for the particular use of the inlet structure of the present invention. The choice may be made immediately without undue experimentation.

The upstream processing unit 458 may include, for example, a semiconductor manufacturing tool and associated emission gas processing apparatus. Such emission treatment apparatus may also include an oxidizer for oxidizing the oxidizable component in the emission gas. Suitable oxidation devices are of a wide variety of types and may be comprised, for example, of thermal oxidation units, electrothermal oxidation devices and the like.

When the upstream processing unit 458 includes gas generating means and gas processing means for the semiconductor manufacturing process, the airflow injected into the inlet 420 of the first flow passage member 412 may be elevated in temperature. There may be a substantial concentration of particulate solids in the form of particles, for example, submicron size.

The interface structure 410 further includes a second flow passage member 424, which is spaced from the first flow passage member as shown while surrounding the first flow passage member 412. To form an annular volume 430 therebetween. The lower end 468 of the second flow passage member 424 extends downwards below the lower end of the first flow passage member 412, so that the open outlet 422 of the first flow passage member 424 is the second flow passage 424. Is spaced in the vertical direction with the open bottom 468 of. As mentioned above, the position of the outlet 422 of the first flow passage member may vary widely in the vertical direction in accordance with the broad practice of the present invention.

The second flow passage member 424 includes a liquid permeable top 426, as shown, and the remaining liquid impermeable bottom 428 extending downward therefrom. The liquid permeable top 426 and the liquid impermeable bottom 428 may be formed in any suitable manner by first joining the separated porous cylindrical top 426 and the rigid walled cylindrical bottom 428, These parts are then joined to each other by soldering, soldering, welding, mechanical fastening fixtures, or other suitable methods by suitable joining means and methods.

Optionally, the second flow passage member 424 may be formed using one cylindrical tubular member, the upper portion of which may be water jet machined, etched, sintered, micro electromachined, or porous or permeable of the tubular member. Liquid permeability is exhibited by processes such as other suitable techniques that can be imparted on top. Preferably, the second flow passage member is formed of a top and a bottom that are initially separated and then joined together, the top of which consists of a porous sintered metal material, a porous plastic material, a porous ceramic material, or other porous material. The porosity is sufficient to allow liquid to permeate through the pores, as described in more detail below.

The gas / liquid interface structure 410 further includes an outer wall member 434 that completely surrounds the second flow passage member and forms an annular inner portion 470 therewith. The outer wall member 434 includes a cylindrical sidewall 436, a top wall 438 and a bottom wall 440, which cooperate to surround the annular inner portion 470. The side wall 436 is provided with a liquid injection port 442. This liquid injection port may be provided in a suitable manner, but in the illustrated embodiment consists of a tubular port extension 444. Optionally, the liquid injection port may simply be an opening or orifice in the side wall, or other liquid inlet structure, whereby liquid can be injected into the annular volume 470 from an external liquid source.

In the embodiment of FIG. 5, the liquid injection port 442 is coupled with a liquid injection line 446 that incorporates a flow control valve 448. Liquid injection line 446 is connected to liquid supply reservoir 450.

FIG. 6 is a top plan view of the apparatus of FIG. 5, showing a tangential feeding device for liquid supply flowing into the annular inner portion 470 of the interface structure shown in FIG. 6. FIG. 6 shows a tubular port extension 444 arranged to tangentially intersect with the cylindrical sidewall of the outer wall member. In this way, the injection liquid is fairly evenly distributed in the circumferential direction around the porous cylindrical upper segment or the liquid permeable top 426, so that the liquid film that seeps through the porous cylindrical segment is thus also described in more detail below, The wall inner surface 472 is evenly enclosed in the circumferential direction.

The liquid flow control valve 448 of the liquid injection line 446 is coupled to a suitable controller / timer means including a central processing unit (CPU), a microprocessor, a flow control console and / or auxiliary monitoring and control means. To provide a predetermined or in other words a selected liquid flow from reservoir 450 through liquid injection line 446 to liquid inlet port 442. The injected liquid fills the annular inner portion 470, which may be injected under suitable processing conditions.

The liquid in the annular volume 470 may be water or other aqueous media for the treatment of an airflow, such as an emission airflow, in which particles released during semiconductor manufacturing operations accumulate significantly.

Thanks to the liquid permeability of the liquid permeable top 426 of the second flow passage member 424, the liquid is permeated from the annular inner volume 470 through the liquid permeable top 426 of the second flow passage member and the liquid permeable top It appears as a droplet 454 on the wall inner surface 432 of the substrate.

These effluent droplets descend under the influence of gravity to coalesce and coalesce with other liquid droplets to form a downward flow liquid film 456 on the wall inner surface 472 of the liquid impermeable lower portion of the second flow passage member. The liquid in the liquid film discharged from the lower open end 468 of the second flow passage member may, for example, be directed to suitable collection and processing means (not shown) for the co-treatment of the downstream processing unit 464, Airflow flows from the gas flow passage 452 of the second flow passage member of the liquid injection line 462.

The downstream treatment unit 464 may be a water purifier, a reaction chamber, or other treatment apparatus or processing zone, where further processing is performed on the airflow that has flowed from the gas flow passage 452 of the liquid injection line 462. At this time, the final discharge gas is discharged from the processing unit downstream of the liquid injection line 466.

Thus, the gas / liquid interface structure 410 is configured to provide an annular volume 430 between the first flow passage member and the second flow passage member by the liquid permeable top 426 of the second flow passage member. In addition, the liquid penetrated through the liquid permeable upper portion may be combined to generate the falling liquid film 456. By this arrangement, the gas flowing from the flow passage 418 to the flow passage 452 impinges on the wall inner surface 472 below the second flow passage member and is covered with the protective liquid film 456. Thus, corrosive species in the gas discharged from the open bottom 422 of the first flow passage member may be 'buffered' with respect to the wall inner surface, thereby causing corrosion on this wall inner surface of the second flow passage member. And minimize adverse reaction effects.

In addition, by injecting liquid into the annular inner portion 470 between the second flow passage member and the outer wall member 434, a liquid reservoir 'jacket' structure is provided. As a result, a liquid is provided on the porous top of the second flow passage member, passes through it, and flows downward to form a protective thin film on the wall inner surface of the second flow passage member.

This falling thin film on the inner surface 472 of the second flow passage member also serves to co-extract particles from the air stream which may be deposited and aggregated on the wall inner surface of the second flow passage member in the absence of such a liquid film. .

Thus, the falling liquid film not only provides a protective function with respect to the inner wall surface of the second flow passage member, but also entrains the extraction of particulate solids and other gaseous components that may be harmful if accumulated on the inner wall surface of the second flow passage member. Provide the medium.

As another advantage of this structure, which is illustrated by way of example in FIG. 5, the use of the liquid permeable top 426 serves to minimize liquid usage compared to the installation of structures such as liquid overflow banks, in which the annular content The liquid exiting 470 simply flows downward at the top of the liquid permeable top 426 and flows downward in the form of a thin film on the wall over the entire length of the inner surface of the second flow passage member. The liquid required for operation is maintained at a very low level by the wetting weir structure of the present invention.

Another advantage of the inventive weeping weir structure over the simple liquid overflow weir structure is that the liquid overflow weir structure is impaired or impaired in operating structure efficiency, while the liquid overflow weir structure is vertically precisely aligned to operate efficiently as designed. There is room to be deflected from the vertical orientation without.

In other words, the weeping weir structure of the present invention is characterized in that the water flowing over the weir further decreases from the height of the interface structure due to the minimum wet rate by the liquid permeable weir wall (according to conventional overflow structures, weir Liquid thresholds are not set and maintained so that liquid outflow starts from).

As an illustrative example of a gas / liquid interfacial structure of the type illustrated illustratively in FIG. 5, such a structure may be used downstream of a thermal oxidizer unit that processes gas emitted from a semiconductor manufacturing process, thus, within line 460. The temperature of the air stream entering the interface structure 410 is raised, and not only particles of submicron size or larger solids but also particles such as silicon such as corrosive solids, granular metals, and the like are accumulated.

In such an embodiment, the liquid permeable top 426 of the second flow passage member may be comprised of a sintered metal wall that is 1/16 inch thick and the average size of the forming holes is about 2 microns. The first flow passage member 412 may be about 4.48 inches long and may be about 2.5 inches in diameter. In accordance with this, the length of the second flow passage member 424 is about 13.5 inches and the diameter is about 4.5 inches. The outer wall member 434 may have a vertical length of about 5.5 inches and a diameter of about 6 inches.

In this system, water may be used as the liquid medium, where water is injected from the reservoir 450 into the annular volume 470 and onto the inner surface 432 of the liquid permeable top 426 of the second flow passage member. Soak in. The water usage of such a system may be on the order of 0.1 to 0.3 gallons per minute during operation.

7 shows an upstream system 512, a discharge line 514, a manifold duct line 516, a first suction line 518 and a second suction line 520, and a downstream purifier unit 550 that generate exhaust gas. A system 510 is shown schematically. As shown, an upstream system, which may include, for example, a semiconductor manufacturing facility or semiconductor processing tool, is in fluid communication with the purifier unit in airtight fashion via the manifold and the suction line. The diameter of the discharge line, the manifold duct line and the suction line can suitably be, for example, 1.5 to 3 inches (3.81 to 7.62 cm).

8 schematically illustrates an exemplary embodiment of the present invention. The upstream system 612, for example a semiconductor manufacturing tool, is connected to the discharge line 614. Discharge line 614 has an inner flow passage and has an elongated tubular wall with a second end and an upstream first end thereof. A first end of the discharge line 614 is connected to the upstream system 612 such that the internal passageway receives gas exiting the upstream system. The second end of the outlet line 614 is connected to approximately an intermediate point of the intake manifold line 616. Suction manifold line 616 has an inner flow passage and an elongated body forming wall having a first end and a second end. Approximately midpoint of the first and second ends of the intake manifold line 616 is downstream of the discharge line 614. The connection of the discharge line 614 and the intake manifold line 616 allows the exhaust gas to efficiently pass from the internal flow passage of the discharge line 614 into the internal flow passage of the manifold line 616.

First suction line 618 and second suction line 620 have internal flow passages and walls forming first and second ends. The first end of each of the first suction line 618 and the second suction line 620 is connected to the first end and the second end of the manifold line 616 such that the exhaust gas is inside the manifold line 616. Easy passage from the flow passage to the internal flow passages of the suction lines 618, 620. The suction lines have a second end downstream of the first end. A second end of each of the first suction line 618 and the second suction line 620 is connected to the purifier unit 650.

As shown, the purifier unit 650 is connected to the purifier channel 652. The connection allows water to pass easily from purifier unit channel 652 to purifier unit 650. Purifier unit 650 is also connected to gas discharge line 654 so that gas from purifier unit 650 passes through discharge line 654 to the discharge position. Purifier unit 650 is also connected to liquid waste line 656 so that liquid waste passes from purifier unit 650 to the liquid waste discharge location without blockage. Purifier channel 652, gas discharge line 654, fluid waste line 656, discharge line 614, manifold suction line 616, and first suction line 618 and second suction line 620. May have a specific gas flow rate and a diameter suitable for operation of a processing unit provided in the installation.

Since the connection between the manifold suction line and the first suction line and the second suction line is made at an angle between 45 and 90 °, the internal flow passage of the manifold suction line is the internal passage of the first suction line and the second suction line. It serves as a water baffle that inhibits water backflow within.

Adjacent to the upstream ends of the first suction duct and the second suction duct, a first suction valve 622 and a second suction valve 624 are connected. These intake valves are two-way valves, each having an open position and a closed position. When in the closed position, the intake valve prevents exhaust gas from flowing from the manifold line 616 to the intake line.

Adjacent to the downstream second end of the suction line, first heating means 646 and second heating means 648 are located. Although shown as a heating coil, these heating means can include any heating system that delivers thermal energy known to those skilled in the art to the internal passages of the first and second suction lines. For illustration, the heating means is considered as a heating coil.

A gas delivery system for delivering gas from a gas source to the inner passages of the first and second suction lines will now be described. The gas delivery system of the present invention comprises a gas source 626, a first gas delivery line 628 and a second gas delivery line 632 with internal passages, a first end and a second end, and an air flow control valve 630, 634.

It will be appreciated that the gas delivery system described herein may have one or more gas sources. A plurality of gas sources are connected in gas udon communication to the gas source manifold. The gas source manifold may comprise a gas source shutoff valve of each gas supply zone and a gas source flow control valve for each gas source. Thus, the gas source manifold is connected in gas flow communication to the gas delivery system.

Gas source 626 is located adjacent to the first suction line and the second suction line. The gas source 626 supplies gas, such as nitrogen, to the internal passages of the first suction line 618 and the second suction line 620 at a rate of 2 to 100 ft ³ per hour. Effective gas delivery to the suction line is facilitated by the connection (by appropriate connection means such as couplings, connectors, etc.) of the first and second gas delivery lines with the first and second suction lines.

Gas source 626 is connected to the first end of first gas delivery line 628. The first end of the second gas delivery line 632 is connected to the first gas delivery line at approximately an intermediate point along the length of the first gas delivery line 628. The connection of the first gas transportation line 628 and the second gas transportation line 632 passes through the inner passage of the second gas transportation line 632 without the blockage or leakage of gas contained in the first gas transportation line 628. . The second gas delivery line 632 is along the length of the first gas delivery line 628 at a point downstream of the connection between the first gas delivery line 628 and the gas source 626. )

The downstream end of the first gas delivery line 628 is connected to the second suction line 620 downstream of the second valve 624. The connection between the first gas delivery line 628 and the suction line 620 allows the gas contained in the inner passage of the first gas delivery line 628 to flow without clogging, so that the gas is free to leak and freely enter the interior of the suction line 620. It flows into the passage. The second end downstream of the first end of the second gas delivery line 632 is connected to the first suction line 618. The connection between the second gas delivery line 632 and the suction line 618 allows the gas contained in the second gas delivery line 632 to flow freely into the suction line 618 without leakage and free of leakage.

A first gas valve is located downstream of the connection with the second gas delivery line 632 upstream of the connection with the second suction line 620 along the first gas delivery line 628. The first gas valve 630 is a two-way valve such as the first suction valve and the second suction valve described above. The first gas valve 630 controls the passage of gas to the second suction line 620 along the interior of the first gas delivery line 628. A second gas valve 634 is located upstream of the connection with the first suction line on the second gas delivery line. The second gas valve 634 facilitates the passage of gas from the second gas delivery line to the first suction line.

The pressurized water transport system will now be described. The water transport system includes a pressurized water source 636, a first water supply line 638 and a second water supply line 642 having first and second ends and internal passageways, a first water valve 640, and A second water valve 644 is provided.

A pressurized water source 636 is positioned adjacent to the first suction line and the second suction line. Pressurized water source 636 generates a flow of 0.5 to 5 gallons of water per minute under pressure. The pressurized water source 636 is connected at one end of the first water supply line 638 to its inner passage. This connection allows pressurized water to flow efficiently from the pressurized water source into the internal passageway of the first water supply line 638. A second end downstream of the first end of the water supply line 638 is connected to the second suction line 620 to direct pressurized water from the internal passage of the first water supply line 638 to the second suction line 620. Transport by internal passage. A first water valve 640 is positioned upstream of the connection with the second suction line 620 on the first water supply line 638 to facilitate pressurized water to selectively flow through the suction line 620. The first water valve is a two-way valve.

The first end of the second water delivery line 642 is connected to the first water delivery line 638 at a location downstream of the pressurized water source 636 upstream of the first water valve 640. A second end downstream of the first end of the second water transport line 642 is connected to the first suction line 618 to direct pressurized water from the internal passage of the first water transport line 638 to the first suction line 618. To the inner passageway. A second water valve 644 is connected to the second water transport line upstream of the connection with the first suction line 618 on the second water transport line to selectively control the passage of pressurized water. The second water valve 644 is a two-way valve.

The first heat jacket 658 has a first suction line 618 of a predetermined length, a first suction valve 622, a connection between the first suction line 618 and the second gas transportation line 634, the first A connection between the first suction line 618 and the second water transport line 634 and the first heating means 648 are received. The first heat jacket provides insulating properties to the components contained therein and, in coordination with the heating means, raises the internal temperature of the first suction line 618. The first heat jacket 658 raises the temperature of the sidewalls while nitrogen flows to evaporate the water deposited on the sidewalls and prevents the condensable process gas from condensing in the first suction line. In the case of metal etching processing, boron trichloride forms boric acid under hydrolysis at the entrance of the clarifier by processing, but the treatment line must be heated to prevent AlCl ₃ from condensing along this line. The line can then be heated from the processing source as in the case of metal etching or WCVD processing.

The second heat jacket 660 has a second suction line 620 of a predetermined length, a second suction valve 624, a connection between the second suction line 620 and the second gas line 628, and the second A connection between the suction line 620 and the second water line 638 and the second heating means 646 are received. The second heat jacket provides insulation properties to the components contained therein and, in coordination with the heating means, increases the internal temperature of the second suction line 620.

The aforementioned valves are two-way valves each having an open position and a closed position. For the purposes described below, these valves are pneumatically opened by air and closed by springs during operation (these valves may also be closed by air or open by springs depending on the requirements, performance and use of the system). Assume it is a valve. Such pneumatic valves may include a KF-50 connection, an electro-pneumatic valve integrated with an air solenoid valve, and a switch opening and closing test lead. Such a valve may be a model name 190 available from MKS Instruments Inc., HPS Division. The electrical connection between the valve described above and the valve described later is maintained at a control panel (not shown). The control panel includes a programmable logic controller (PLC) in electrical connection with the system valve. The PLC maintains an electrical connection with the valve to monitor the valve position and the valve actuation position (ie, open or closed position). In addition, a timer cooperates with the PLC to facilitate PLC timing of the valve position. However, it will be understood by those skilled in the art that other valve and control embodiments may be substituted without departing from the spirit and scope of the present invention. For example, the valve may be composed of an electric valve, a mechanical valve, an electromagnetic valve, or other valves of various kinds on the market. Such a valve may in particular comprise a limit switch electrically coupled to a cycle timer control means or an alternating current control means. This limit switch allows the valve position to be identified and controls mutual locks to ensure that no process airflow is returned and prevents water from being injected into the connection line (flow connection) gas flow line.

The method of operation of the above-described embodiment of the present invention shown in FIG. 8 will now be described with reference to the flowchart of FIG. 9. In this embodiment, reference numerals for the same components are made to coincide with reference numerals in FIG. 8.

In a first step of the method of operation of the present invention (see block 701 in the flow chart of FIG. 9), all valves 622, 624, 630, 634, 640, 644 are closed. A programmable logic controller (PLC) controls the opening and closing of the valves by regulating the flow of compressed air (not shown) directed to the valves. Shut off the compressed air directed to the valve causes the spring to move the valve baffle to the shut off position, preventing airflow from flowing from the upstream valve position to the downstream valve position. This first step prevents effluent gas, pressurized water or other gas from flowing through any of the aforementioned duct lines. This initial step is a safety precaution before using the device of the present invention, allowing the operator to know that the intake duct line is always filled with gas exiting the upstream system 612. This initial step ensures that the flow of effluent gas (along with pressurized water and gas from gas source 636) has not yet begun.

The second step of the method of operation of the present invention (see block 702 in the flow chart of FIG. 9) includes searching for whether all valves are closed. This search is performed by a PLC built into the control panel. As mentioned above, the PLC is in electrical communication with an electrical position indicator means built in the aforementioned valve. This search is carried out by detecting a signal from the position indicator means by the PLC and comparing this signal with a predetermined valve indicating the closed position. If it is determined that the aforementioned valve is in the closed position, a third step is initiated. If it is determined that the valve described above is in the open position, a beep sounds and the previous step is repeated.

The third step (see block 703 in the flow chart of FIG. 9) involves the opening operation of the second intake valve 624. Opening of the second intake valve 624 is accomplished by the flow of compressed air into the valve such that the inner spring adjusts the position of the valve baffle such that the effluent gas is forced from the manifold 616 to the second intake valve 624. The second suction line 620 may be passed through. Opening of the second suction valve 624 is operated by the PLC. Since the first intake valve 622 is held in the closed position, the first intake line is sealed so that no outflow gas flows and the gas flows only through the second intake line 620.

The fourth step (see block 704 in the flow chart of FIG. 9) involves searching for whether the second intake valve 624 is open. The position search of the second suction valve is performed by the PLC in the same manner as the valve position search performed in the second step. If the PLC determines that the second intake valve is closed, the alarm sounds and the previous step is repeated. If the PLC determines that the second suction valve is open, the next step of the operation sequence is performed.

The fifth step (see block 705 in the flow chart of FIG. 9) involves opening the second water valve 644. Opening of the second water valve 644 is performed by the PLC similarly to the method described above. The opening of the second water valve 644 is an outlet for flowing pressurized water from the pressurized water source 636 through the first water transport line 638 and the second water transport line 642 to the first suction line 618. To form. The first water valve 640 is maintained in the closed position to ensure that no pressurized water flows from the pressurized water source 636 through the first water valve to the second suction line 620. The second water valve 644 is kept open by the PLC during the first timed period and monitored by a timer that cooperates with the PLC. The second water valve 644 remains open for 1 to 10 minutes. The pressurized water flowing into the first suction line 618 is jetted to not only flush the internal passageway of the first suction line 618 but also dissolve the dissolved particles such that the particles and the like are purged through the second end of the first suction line. Discharge to unit 650.

A sixth step (see block 706A in the flowchart of FIG. 9) involves closing the second water valve 644 after the first period of time. After closing the second water valve 664, open the second gas valve 634 (see block 706B in the flow chart of FIG. 3) and activate the first heating means if it is not already operating. (See block 706C in the flow chart of FIG. 3). Closing and opening of the valve is performed by the PLC in the manner described above. The first heating element is operated by generating a current flowing through the element and controlled by the PLC. The electric current is affected by the intrinsic resistance of the heating means and generates heat due to its electrical resistance. The second gas valve 664 remains open for a second period of time and is monitored by a timer that interacts with the PLC. The preferred range of the time for leaving the second gas valve open and the operating time of the heating means is 30 minutes to 8 hours. The first gas valve is maintained in the closed position such that gas flow from the gas source 626 is directed along the first gas delivery line 628 to the second gas delivery line 632 and the first suction line 618. . In cooperation with the heat transferred by the first heating means 648, the gas dries the inner wall of the first suction line.

The seventh step (see block 707 in the flow chart of FIG. 9) involves separating the first heating means and opening the first intake valve 622. Opening of the first intake valve 622 is performed similarly to the method described above. The heating means are separated by cutting off the current flowing to the heating means under control by the PLC.

An eighth step (see block 708 in the flow chart of FIG. 9) involves searching for whether the first intake valve 622 is open. The retrieval is executed by the PLC similarly to the retrieval method described above. If the PLC determines that the first intake valve is open, an alarm sounds and the seventh step is repeated. Only when the PLC indicates that the newly cleaned inlet is open, the PLC will close the other inlet for cleaning, otherwise the flow of process gas may be interrupted. If the PLC determines that the first suction valve is open, the next step of the operating sequence is executed.

The ninth step (see block 709 in the flow chart of FIG. 9) involves closing the second intake valve 624. The first suction valve 622 is maintained in the open position. By closing the second intake valve 624 the flow of gas is diverted from the second intake line that is currently closed to the first intake line that is currently open.

The tenth step (see block 710 in the flow chart of FIG. 9) involves searching for whether the second intake valve 624 is closed. This retrieval is performed by a PLC that is electrically connected to the second intake valve as described above. If the PLC determines that the second intake valve is not closed, an alarm sounds and the ninth step is repeated. If it is determined that the second suction valve is closed, the next step of the operation sequence is executed.

The eleventh step (see block 711 in the flow chart of FIG. 9) involves opening the first water valve 640. The second water valve 644 is maintained in the closed position. By opening the first water valve (with the second water valve 644 closed), the pressurized water passage is opened so that the pressurized water from the pressurized water source 636 and the first water transport line 638 and the first water valve Flow through 640 to a second suction line 620. The second water valve 644 is maintained in the closed position to prevent water from flowing through the valve to the first suction line 618. Pressurized water flows through the second suction line 620 to perform a cleaning and cleaning action as described above in connection with the first suction line. Pressurized water is discharged to the second suction line through a second end connected to the clarifier 650. Pressurized water is ejected from the second suction line for a predetermined time of 1 to 10 minutes. An adjustable timer, electrically connected to the PLC, cooperates with the PLC simultaneously with the discharge of pressurized water.

The twelfth step (see block 712 in the flowchart of FIG. 9) closes the first water valve 640, and the thirteenth step (see block 713 in the flowchart of FIG. 9) the first gas valve ( Opening 630 and the fourteenth step (see block 714 in the flow chart of FIG. 9) involve operating second heating means 646. Opening and closing of the valves is executed by the PLC in a manner similar to the above-described method. The second gas valve 634 is maintained in the closed position to prevent gas from flowing out of the first suction line 618 through this valve. Opening of the first gas valve 630 opens the gas passage so that gas flows from the gas source 626 through the first gas delivery line 628 and the first gas valve 630 to the second suction line 660. To flow. The operation of the second heating means cooperates with the second heat jacket 660 to raise the internal temperature of the second suction line. Gas and heat generated from the second heating means dry the inner passage of the second suction line 620. Gas enters purifier 650 via a second suction line via its second end. The first gas valve is kept open and the second heating means is operated for a range of 30 minutes to several hours. This period is sensed by a timer cooperating with the PLC as described above.

The fifteenth step (see block 715 in the flow chart of FIG. 9) involves closing the first gas valve 630 to separate the second heating means 646 after reaching the set period. In a sixteenth step (see block 716 in the flow chart of FIG. 9), the PLC searches if the first intake valve 622 remains open. The valve is operated in the manner as described above.

The seventeenth step (see block 717 in the flowchart of FIG. 9) involves opening the second intake valve 624, and the eighteenth step (see block 718 in the flowchart of FIG. 9) is performed by the PLC. Retrieving whether the second intake valve 624 is open. If it is determined that the second intake valve is not open, a beep sounds and the previous step is repeated. The PLC performs search processing similar to the above-described method.

A nineteenth step (see block 719 in the flow chart of FIG. 9) involves closing the first intake valve 622 and a twentieth step (see block 720 in the flow chart of FIG. 9) refers to this first suction. Investigating whether the valve is securely closed. If valve 622 is not closed, a beep sounds and the previous step is repeated. If the first suction valve 622 is closed, the operator searches for the following operation processing.

Finally, the operator retrieves whether to return to the fifth step to repeat the above-described cleaning step, or to end the cleaning cycle (see block 721 in the flowchart of FIG. 9).

The inlet structure of the present invention comprises a downstream processing unit such as an air purifier, purifier, filter, neutralization unit, extraction system for recovery of airflow components, reaction system for further gas treatment of the composition of gas obtained at an upstream location, and the like. This is useful for connecting and using. The inlet structure is constructed, arranged, and operated to minimize the frequency of deposition of the inlet, thin film formation due to airflow components, and the occurrence of harmful hydrodynamic effects.

Claims (78)

An inlet structure for passing airflow from an upstream source to a downstream point, (A) a gas permeable wall surrounding the gas flow path; An outer annular jacket surrounding the gas permeable wall to form an annular gas reservoir between the gas permeable wall; While the gas flows through the gas permeable wall through either the particulate solid containing air stream and the particulate solid forming air stream, or both, through the inlet structure, solids deposit on the inner surface of the gas permeable wall, or An inlet structure comprising gas injection means for injecting gas into said annular gas reservoir at a pressure sufficient to prevent formation thereof; (B) a first flow passage member extending in a vertical direction having an upper introduction portion for injecting the airflow and a lower end portion for discharging the airflow; Surrounds the first flow passage member at regular intervals to form an annular volume therebetween, the bottom portion extending downward below the bottom portion of the first flow passage member, the liquid permeable portion of the upper portion and the liquid A second flow passage member having a lower liquid impermeable portion below the permeable portion; An outer wall member surrounding and enclosing the second flow passage member to form an annular inner portion surrounded with the passage member; And An inlet structure disposed in said outer wall member, said liquid flow inlet port for injecting liquid into said enclosed annular internal volume between said second flow passage member and said outer wall member; An inlet structure selected from the group consisting of: An anti-clogging inlet structure for injecting a particulate solid containing air stream and a particulate solid forming air stream, or one of them into the gas treatment system, A gas permeable wall surrounding the gas flow path; An outer annular jacket surrounding the gas permeable wall to form an annular gas reservoir between the gas permeable wall; While the particulate solid containing air stream and the particulate solid forming air stream, or one of them, flow through the inlet structure to the gas treatment system, the gas penetrates the gas permeable wall so that solids deposit on the inner surface of the gas permeable wall or Gas injection means for injecting gas into the annular gas reservoir at a pressure sufficient to inhibit formation Inlet structure comprising a. 3. The system of claim 2, further comprising a port for injecting pulsed high pressure gas into the annular reservoir, the port for pulsed conveying high pressure gas from and to the annular gas reservoir. An inlet structure, connected to the means, to perform an additional anti-clogging action on the gas permeable wall. The gas flow permeable wall and the outer annular jacket are connected to a downward flow path section including a wall surrounding a corresponding further gas flow section and forming a slot therebetween with the gas permeable wall. The wall of this downward flow passage section is surrounded by an outer annular jacket to form an annular gas reservoir in liquid overflow relationship with the slot therebetween, so that the point where the annular liquid reservoir is determined by the height of the wall When a liquid is filled past the liquid flows down on the inner surface of the wall as a falling liquid film, whereby the falling liquid film provides a barrier medium to the inner wall of the wall to deposit or form a solid on this inner surface. To remove any solids deposited or formed on the inner surface of the wall and nevertheless Inlet structure characterized in that. 5. The inlet structure according to claim 4, wherein an outer annular jacket of the downflow flow section of the inlet structure is provided with a port connected to the liquid supply. The inlet structure according to claim 2, wherein the first end of the gas flow path is connected to the semiconductor manufacturing tool in a gas flow relationship. 7. The inlet structure according to claim 6, wherein the second end of the gas flow path is connected to the water purification unit in a gas flow relationship. 7. The inlet structure according to claim 6, wherein the second end of the gas flow path is connected to the combustion purification unit in a gas flow relationship. The inlet structure according to claim 2, wherein the inlet structure further comprises an air flow conduit surrounded by an outer annular jacket for transporting the particulate solid-containing air stream and the particulate solid-forming air stream, or either of these, to the inlet structure. . 10. The inlet structure of claim 9, wherein said inlet structure further comprises heating means for heating said airborne conduit to prevent condensation of particulate solid-containing airflow and particulate solid-forming airflow flowing through said airflow conduit, or one of these. Inlet structure, characterized in that. 5. The inlet structure according to claim 4, wherein the inlet structure further comprises an air flow conduit enclosed by a gas permeable wall for transporting a particulate solid containing air stream and a particulate solid forming air stream, or both. . 12. The inlet structure of claim 11, wherein said inlet structure further comprises heating means for heating said airborne conduit to prevent condensation of particulate solids and particulate solid forming airflow flowing therethrough. Inlet structure, characterized in that. 12. The inlet structure as claimed in claim 11, wherein the air flow pipe discharges the particulate solid-containing air stream and the particulate solid-forming air stream, or one of them below the upper end of the wall of the downstream flow section. The inlet structure according to claim 2, wherein the inlet structure also comprises gas heating means for heating the gas passing through the gas permeable wall. An anti-clogging inlet structure for injecting a particulate solid containing air stream and a particulate solid forming air stream, or one of them into the gas treatment system, A first flow passage section and a second flow passage section disposed generally in a vertical direction in a mutually connected relationship; A gas flow port on an outer wall of the first flow passage section, The first flow passage section and the second flow passage section form a vertical flow passage in the series connected relationship, wherein one of the granular solid-containing air flow and the granular solid-forming air flow, or one of the granular flow paths, is formed through the flow passage. Flow from a solid containing air stream and a particulate solid forming air stream, or one of the upstream sources, to a downstream gas treatment system disposed in an air flow receiving relationship with the inlet structure, The first flow passage section includes an upper section of the inlet structure, and has a gas permeable wall having an inner surface defining an upper portion of the first flow passage and surrounding and enclosing the gas permeable wall; An outer wall forming an annular inner portion between The gas flow port may be connected to a gas source that introduces gas into the annular volume at a predetermined gas flow rate for continued flow of gas from the annular volume into the flow passage of the inlet structure, The second flow passage section is connected in series to the first flow passage section such that particulate solid containing fluid flows downwardly from the first flow passage section into the second flow passage section. And an inner weir wall disposed at regular intervals with respect to the outer wall, the inner weir wall forming an annular inner portion between the outer wall and the second flow passage section. An outer wall is connected with the first flow passage section and the inner weir wall extends toward the gas permeable wall of the first flow passage section but terminates just before the gas permeable wall to provide a gap therebetween. Wherein the inner weir wall has an inner surface defining a flow passage of the second flow passage section; Thus, when liquid enters into the annular volume between the outer wall of the second flow passage section and its inner weir wall, the injected liquid overflows the weir and flows downwards to the inner surface of the inner wall of the second flow passage section. To wash away any particulate solid from its inner weir wall and to prevent solids from depositing or forming on the inner surface of the weir wall as the flow of particulate solids flows through the flow passages of the inlet structure. Inlet structure. 16. The apparatus of claim 15, further comprising a high pressure gas flow port on an outer wall of the first flow passage section, the high pressure gas flow port configured to pressurize the high pressure gas to clean particles deposited or formed thereon from the gas permeable wall. An inlet structure, which can be connected to a high pressure gas source for inlet. 16. The inlet structure of claim 15, wherein said inlet structure is connected to a gas source at a gas port on an outer wall of said first flow passage section. 17. The inlet structure as claimed in claim 16, wherein the inlet structure is connected to a high pressure gas port at an outer wall of the first flow passage section. 16. The inlet structure according to claim 15, wherein the inlet structure is connected to a water purifier for purifying particulate solid-containing airflow flowing through the flow passage of the inlet structure. The inlet structure according to claim 15, wherein the first flow passage section and the second flow passage section are connected to each other so as to be quickly separated from each other. 16. The inlet structure according to claim 15, wherein said first flow passage section and said second flow passage section are coaxially aligned with each other. The inlet structure according to claim 15, wherein the gas permeable wall is formed of a porous metal. The inlet structure according to claim 15, wherein the gas permeable wall is formed of porous ceramics. The inlet structure according to claim 15, wherein the gas permeable wall is formed of porous plastic. 16. The inlet structure according to claim 15, wherein the gas permeable wall and the annular jacket on the outside thereof are formed in a circular cross section. 16. The inlet structure according to claim 15, wherein the outer wall and the inner weir wall of the second flow passage section are formed in a circular cross section. 16. The inlet structure as claimed in claim 15, wherein said first flow passage section is connected with an upstream semiconductor fabrication tool. 16. The air flow conduit of claim 15, wherein the inlet structure further comprises an air flow conduit surrounded by an inner surface of the gas permeable wall, the air flow conduit in a gas flow receiving relationship with an upstream source. An inlet structure, characterized in that it discharges a particulate solid-containing air stream and a particulate solid-forming air stream, or both, generally in a vertical flow passage. 29. The inlet structure as claimed in claim 28, wherein said air flow conduit discharges either a particulate solid containing air stream and a particulate solid forming air stream in the second flow passage section, or one of them. 29. The inlet structure according to claim 28, wherein said air flow pipe discharges a granular solid containing air stream and a granular solid forming air stream, or one of them, below the gap forming said weir. 29. The inlet structure as claimed in claim 28, wherein the air flow pipe discharges the granular solid-containing air stream and the granular solid-forming air stream, or one of them, over the gap forming the embankment. 16. The apparatus of claim 15, wherein the inlet structure further comprises heating means for heating the airborne conduit to prevent condensation of particulate solid containing air and granular solid forming airflow, or one of them, flowing through the airflow conduit. Inlet structure characterized in that. 16. The inlet structure according to claim 15, wherein said inlet structure also comprises gas heating means for heating a gas passing through said gas permeable wall. An anti-clogging inlet structure for injecting a particulate solid containing air stream and a particulate solid forming air stream, or one of them into a gas treatment system, comprising: an upper section having an upper porous wall and a lower section having a lower porous wall; An inlet structure, wherein the porous wall and the lower porous wall surround a gas flow path and each porous wall contains a protective fluid. 35. The air flow conduit of claim 34 wherein the inlet structure further comprises an air flow conduit for particulate solid-containing air and particulate solid-forming airflow in the upper section, or one of the outlets, surrounded by the upper porous wall. Inlet structure. 35. The inlet structure of claim 34, wherein the inlet structure further comprises an air flow conduit for evacuating particulate solid-containing air and particulate solid-forming airflow in the lower section, or one of which is surrounded by the upper porous wall. The entrance structure. 35. The air flow passage of claim 34, wherein the inlet structure also includes a transition region and an air flow conduit between the upper section and the lower section, wherein the air flow conduit comprises particulate solid-containing air flow and particulate solid forming airflow within the transition region, or double Inlet structure, characterized in that to discharge one. 35. The inlet structure of claim 34, wherein said inlet structure also comprises a porous structure disposed axially for injecting fluid into the inlet structure. A gas / liquid interface structure that delivers airflow from an upstream gas source to a downstream processing unit, A first flow passage member extending in a vertical direction having an upper introduction portion for injecting the airflow and a lower end portion for discharging the airflow; Surrounds the first flow passage member at regular intervals to form an annular volume therebetween, the bottom portion extending downward below the bottom portion of the first flow passage member, the liquid permeable portion of the upper portion and the liquid A second flow passage member having a lower liquid impermeable portion below the permeable portion; An outer wall member surrounding and enclosing the second flow passage member to form an annular inner portion surrounded with the passage member; And A liquid flow inlet port disposed in the outer wall member for injecting liquid into the enclosed annular inner volume between the second flow passage member and the outer wall member A gas / liquid interface structure comprising a. 40. The gas / liquid interface structure of claim 39, wherein the upper liquid permeable portion of the second flow passage member comprises a porous cylindrical wall member. 41. The gas / liquid interface structure of claim 40, wherein the porous cylindrical wall member is formed of a material selected from the group consisting of sintered metal material, porous ceramic material, and porous plastic material. 41. The gas / liquid interface structure of claim 40, wherein the upper liquid permeable portion of the second flow passage member is formed of a porous sintered metal material. 41. The gas / liquid interface structure of claim 40, wherein the upper liquid permeable portion is constituted by a porous wall having an average pore dimension in the range of about 0.5 to 30 microns. 40. The gas / liquid interface structure of claim 39, wherein the first flow passage member and the second flow passage member are cylindrical and coaxial with each other. 40. The cylindrical wall member of claim 39, wherein the outer wall member surrounding and enclosing the second flow passage member has a cylindrical side wall disposed in a radially spaced relation with respect to the second flow passage member, and the first flow passage member penetrates. And a bottom wall extending between the second flow passage member and the side wall of the outer wall member. 40. The liquid flow inlet port of claim 39, wherein the liquid flow inlet port disposed in the outer wall member for injecting liquid into the enclosed annular volume portion between the second flow passage member and the outer wall member further comprises injecting injected liquid into the second flow passage member. A gas / liquid interface structure, configured and arranged to tangentially feed liquid into the enclosed annular volume to distribute circumferentially around a liquid permeable portion of the top of the substrate. 40. The gas / liquid interface structure of claim 39, wherein the liquid liquid rate at the weir is constructed and arranged to be independent of the height of the structure. 40. The gas / liquid interface structure of claim 39, wherein the liquid velocity at the weir is constructed and arranged to be independent of the minimum wetting velocity. A gas / liquid interface structure for conveying airflow from an upstream airflow source to a downstream processing unit, comprising a first flow passage member and a second flow passage member defining an annular volume therebetween, wherein the second flow passage member comprises: Extending downwardly at a lower level than a lower end of the first flow passage member, the outer flow member is surrounded by an outer wall member to form an annular interior volume surrounded by the passage member and surrounded by the outer wall member. There is a liquid flow port for injecting liquid into the inner annular volume, and the second flow passage member has a liquid permeable top in liquid circulation relationship with the enclosed inner annular volume, thereby allowing liquid from such volume to Protection for the second flow passage member which can flow through the permeable portion and which is also in the inner surface portion of the second flow passage member A gas / liquid interface structure, which forms a falling liquid film as a liquid interface. 50. The gas / liquid interface structure of claim 49, wherein the liquid permeable top of the second flow passage member comprises a porous cylindrical wall member. 51. The gas / liquid interface structure of claim 50, wherein the porous cylindrical wall member is formed of a material selected from the group consisting of sintered metal material, porous ceramic material, and porous plastic material. 51. The gas / liquid interface structure of claim 50, wherein the liquid permeable top of the second flow passage member is formed of a porous sintered metal. 51. The gas / liquid interface structure of claim 50, wherein the top of the liquid permeability has an average pore dimension in the range of about 0.5 to 30 microns. 50. A gas / liquid interface structure according to claim 49, wherein said first flow passage member and said second flow passage member are each cylindrical and coaxial with each other. 50. The cylindrical wall member of claim 49, wherein the outer wall member surrounding and enclosing the second flow passage member has a cylindrical side wall disposed in a radially spaced relation with respect to the second flow passage member, and the first flow passage member penetrates. And a bottom wall extending between the second flow passage member and the side wall of the outer wall member. 50. The liquid flow inlet port of claim 49, wherein the liquid flow inlet port disposed in the outer wall member for injecting liquid into the enclosed annular volume portion between the second flow passage member and the outer wall member includes: A gas / liquid interface structure, configured and arranged to tangentially feed liquid into the enclosed annular volume to distribute circumferentially around a liquid permeable portion of the top of the substrate. 50. The gas / liquid interface structure of claim 49, wherein the liquid velocity at the weir is constructed and arranged to be independent of the height of the inlet structure and the minimum wetting velocity. As a system for treating outflow gas in semiconductor manufacturing, A semiconductor manufacturing unit for generating outflow airflow; An oxidation unit for oxidizing the outflow air stream; Gas / liquid interface structure that delivers airflow from the oxidation unit to downstream processing units And a gas / liquid interface structure A first flow passage member extending in a vertical direction having an upper introduction portion for injecting the airflow and a lower end portion for discharging the airflow; Surrounds the first flow passage member at regular intervals to form an annular volume therebetween, the lower end of which extends downwards below the lower end of the first flow passage member, A second flow passage member having a lower liquid impermeable portion below the liquid permeable portion; An outer wall member surrounding and enclosing the second flow passage member to form an annular inner portion surrounded with the passage member; A liquid flow inlet port disposed in said outer wall member for injecting liquid into said enclosed annular internal volume between said second flow passage member and said outer wall member; And Downstream treatment unit for receiving an outlet airflow from the gas / liquid interface structure Emission gas treatment system comprising a. An inlet structure for injecting airflow into a gas treatment system, A gas flow passage surrounding wall consisting of an upper wall section surrounding an upper section of the gas flow passage and a lower wall section surrounding a lower section of the gas flow passage; A gas delivery conduit arranged to allow airflow to enter and flow therethrough, disposed in an interior of a gas flow passage, extending axially through at least a portion of an upper section of the gas flow passage surrounded by the upper wall section, and flowing the gas flow. A gas delivery line terminated at the outlet end of the furnace and arranged to discharge the laminar flow of air into the lower section of the gas flow path; The protective gas in the upper section of the gas flow path of the cavity annular laminar flow of air flow flowing through the gas delivery pipe and exiting from the outlet end to the lower section of the gas flow path, the axial laminar flow of the protective gas being the gas delivery pipe. Means for injecting into the lower section of the gas flow path to protect the laminar flow of the air stream discharged from the Inlet structure comprising a. 60. The inlet structure as claimed in claim 59, wherein said wall is constructed and arranged in a supply relationship with a liquid source to provide a falling liquid film on the surface of said wall to prevent contact of said wall with airflow. 60. The inlet structure as claimed in claim 59, wherein the inlet structure is arranged such that gas is released into the gas purifier unit. 60. The inlet structure according to claim 59, wherein the gas delivery line terminates at the outlet end of the lower section of the gas flow path. 60. The inlet structure of claim 59, wherein the upper wall section comprises a gas permeable wall disposed to receive a protective gas from a source, such that the protective gas flows through the gas permeable wall. 60. The inlet structure as claimed in claim 59, wherein said lower wall section comprises a wall portion forming a liquid overflow bank. 60. The inlet structure according to claim 59, wherein the upper wall section and the lower wall section are the same diameter and the gas delivery line is coaxial with the upper wall section and the lower wall section. delete delete delete delete delete delete delete delete delete delete delete delete delete