JP2019195056A - Integrated reflow system with built-in heat recovery device and air purification device - Google Patents

Abstract

To provide a reflow system that prevents the interruption of operations due to the re-installation of ducts, prevents the outflow of contaminated air such as volatile organic compounds, and supplies purified air to a room to solve workers' health problems.SOLUTION: A reflow system includes a heat exchanger (110) that recovers high-temperature heat from a contaminated air discharged from a reflow furnace (10), a condenser (120) that further cools the contaminated air and condenses the flux, and a purification unit including a first air purification device that purifies contaminated air in real time and re-injects the air into the reflow furnace (10), and a second air purification device that purifies contaminated air discharged from an inlet part (30) and an outlet part (40) on both sides of a flow conveyor (20) in real time and discharges the air into the room.SELECTED DRAWING: Figure 2

Description

The present invention relates to a reflow system, including a condenser for condensing flux in the reflow system, a heat exchanger, a roll-to-roll dust collector and an air purifier, and the like. By recovering the high-temperature heat generated and re-introducing it into the reflow furnace, the amount of energy consumed by reflow, that is, the amount of power consumed can be reduced, and in a small space like most factories. The present invention relates to an integrated reflow system including a heat recovery device that prevents a flow of work from being disturbed and an air purification device.

Generally, surface mount technology (Surface Mount Technology, SMT) is a surface mount component (SMC) that can be directly mounted on the surface of a printed circuit board (PCB). As a method of attaching, such surface mounting technology is performed by a soldering method, and a reflow soldering equipment is used. Solder paste (Solder Paste) used for soldering with reflow equipment usually contains 75-92 wt.% Solder alloy powder, the rest being resin (Rosin), viscosity increasing agent and lubrication as binder It is composed of agents.

Conventional reflow equipment uses contaminants such as flux (Flux, fine particle liquid residue) together with odor and volatile organic compounds (VOCs) from the resin during reflow soldering at a high temperature of about 250 ° C. At present, these pollutants are all exhausted by an air conditioner (duct) on the factory via a duct in the upper stage of reflow without further treatment. In addition, bad odors and volatile organic compounds leaked from the reflow equipment, contaminating the air inside the factory and inducing a headache for workers.

In particular, the existing reflow equipment is structured so that the flux generated during soldering cannot be discharged to the outside, so only about 10% is removed by the Fume Management System installed at the bottom of the reflow equipment. The remaining amount is then circulated again in the reflow furnace (爐). As a result, the flux adheres and accumulates on the panel heater inside the reflow furnace, reducing the heat transfer effect of the panel heater, so that not only the power consumption (energy consumption) increases, but also accumulated and adhered to the panel heater. Since the flux that has fallen on the printed circuit board causes poor quality, cleaning work to remove the flux adhering to the panel heater is frequently performed at least once a month. There is also a problem that operation interruption and human power consumption occur considerably.

Also, the fume management system installed in the lower part of the reflow must be cleaned about once a year, but it costs about 3 million yen for cleaning, and it removes the viscous sticky flux when cleaning Not only is the work very difficult, but a large amount of toxic flux odor is released, which seriously harms the health of workers.

At the same time, the contaminated air discharged from the reflow is a high temperature of about 190 ° C, but it is discharged to the outside without any additional treatment for heat recovery. It is also true that a serious level has been reached.

Patent Document 1, which is a prior art, discloses a ductless air purification device for purifying contaminants such as malodors and volatile organic compounds. The ductless air purifier is capable of completely decomposing / removing odors and volatile organic compounds with a combination of a low-temperature plasma reactor, a metal oxide catalyst, and activated carbon, and then exhausting them indoors. Not only can it reduce labor and cost required for installing air conditioning facilities such as ducts, but it can also prevent productivity declines due to operation interruptions due to duct re-installation when the production process is changed. .

However, fine dust and flux generated during reflow soldering, and high-concentration toxic smoke, dust, and fine soot and flux generated when processing high-molecular polyethylene resin in the laser process are pre-filtered. There is a problem that it cannot be properly filtered and is directly sucked into the ductless air purification device.

Thus, substances such as fine dust and flux that have not been removed by the pretreatment filter adhere to the electrode plate of the plasma reactor of the ductless air purifier and the plasma reaction cannot occur properly. There has been a problem that the effect of decomposing and removing pollutants such as volatile organic compounds is reduced. Thereby, the trouble of having to interrupt the operation of the air purification device and periodically clean the electrode plate of the plasma reactor is followed. In addition, metal oxide catalysts, activated carbon, and various types of substances such as fine dust and flux also adhere to various filters, and due to this, the replacement period is shortened in about 3 to 4 months depending on the characteristics of the industrial site. The problem that appears.

On the other hand, the polluted air discharged by reflow is a high temperature of about 190 ° C inside and outside, but the amount of heat (energy) contained in the high temperature contaminated air cannot be recovered, and only the air is collected. Since it is purified and discharged into the room as it is, there is a problem that not only the temperature in the factory room is raised but also the amount of power consumption for reflow is increased.

In addition, the ductless air purification device is installed beside both ends of the reflow equipment, and has a disadvantage in that a work flow line is obstructed when the space is small as in most factories.

On the other hand, Patent Document 2, which is a conventional technique, discloses a roll-to-roll dust collector for collecting and removing fine dust and flux generated during reflow soldering. If the roll-to-roll dust collector is installed in the front stage of the ductless air purifier, fine dust and flux are filtered and collected in advance, so that bad odors and volatile organic compounds are decomposed from the plasma reactor.・ Not only can the removal efficiency be dramatically improved, but the troublesomeness of cleaning the electrode plate of the plasma reactor from time to time has been eliminated, and the life of metal oxide catalysts, activated carbon, and various filters has been extended. It can be extended for a considerable period of about one year. As a result, there is an advantage that operation interruption due to cleaning of the plasma electrode plate of the ductless air purification device is prevented, and maintenance costs are reduced by extending the life of various catalysts, activated carbon and filters.

However, the temperature of the flux sucked by the roll-to-roll dust collector is about 80-90 ° C, and most of it exists in the state of gas-liquid (salt liquid). It passes directly through the filter of the dust device and adheres to the metal oxide catalyst. As a result, there is a disadvantage that the whitening phenomenon occurs and the ozone decomposition effect and the generation of active oxygen on the catalyst surface are reduced.Therefore, over time, as a result, the odor and decomposition of volatile organic compounds occur. There is a problem that the removal effect decreases.

(Patent Literature 0001) Patent Literature 1. Republic of Korea Published Patent Publication No. 2017-0112377 (Patent Literature 0002) Patent Literature 2. Republic of Korea Patent Application No. 2017-0087214

In order to solve the problems of the present invention, the present invention incorporates integrated devices such as a condenser for condensing flux in a reflow system, a roll-to-roll dust collector, a heat exchanger, and an air purification device. This eliminates the need for air-conditioning facilities such as ducts in the upper stage of reflow and makes the work environment comfortable.In addition to preventing interruption of operation due to reinstallation of ducts, it prevents outflow of contaminated air such as volatile organic compounds and is purified Air can be supplied indoors to solve workers' health problems at the same time.

In addition, by recovering the high-temperature heat generated by reflow and re-introducing it into the reflow furnace, it is possible to reduce the amount of energy consumed by reflow, that is, the amount of power consumed, as in most factories. It is an object of the present invention to provide an integrated reflow system incorporating a heat recovery device and an air purification device in which a work flow line is not obstructed in a narrow space.

In order to achieve the above-described problems, an integrated reflow system including a heat recovery device and an air purification device according to the present invention includes a heat recovery device that recovers high-temperature heat from contaminated air discharged from a reflow furnace (soot). A heat recovery unit including a first air purification device that purifies contaminated air that has passed through the heat recovery device in real time and re-injects it into the reflow furnace, and is discharged from the inlet and outlet portions on both sides of the reflow conveyor And a purification unit including a second air purification device that purifies contaminated air in real time and discharges it into the room.

Further, the heat recovery device is composed of a heat exchanger and a condenser, and after the contaminated air discharged from the reflow furnace is cooled to 80 to 90 ° C. through the heat exchanger, the heat recovery device is 60 to 60 through the condenser. After cooling to 70 ° C. and condensing the gas-liquid (salt liquid) state flux in the contaminated air, it is transferred to the first air purification device.

In addition, the condenser includes a fan and a heat sink.

In addition, the first air purification device includes a first nonwoven fabric filter, a roll-to-roll dust collector, and a roll-to-roll dust collector that remove the condensed flux through the condenser. A low-temperature plasma reactor that removes malodors and volatile organic compounds in the air that passed through the dust filter, and fine dust that is generated during the decomposition process of odors and volatile organic compounds in the air that passed through the low-temperature plasma reactor. The medium filter is sequentially attached to one first kit chamber, and the sliding of the first kit chamber is applied by sliding method.

The first air purification device includes a metal oxide catalyst that removes residual ozone contained in the air that has passed through the first kit chamber, exhaust ozone in the air that has passed through the metal oxide catalyst, and An adsorption filter that absorbs and removes carbon monoxide and carbon dioxide produced as by-products in the process of decomposing volatile organic compounds, a hepa filter, and a blower that transfers air through the adsorption filter and the hepa filter into a reflow furnace, It is characterized by being sequentially attached to one second kit chamber.

In the first kit chamber, when one or more of the first nonwoven fabric filter, the dust collection filter of the roll-to-roll dust collector, and the medium filter are changed, the condenser passes through the condenser. The contaminated air is not passed through the first kit chamber, but bypassed to a separate second non-woven filter to remove the condensed flux, and then transferred to the second kit chamber. It is characterized by being.

Further, the purified air cooled to 65 to 70 ° C. through the first air purification device rises to 110 ° C. through the heat exchanger using the contaminated air of 190 ° C. discharged in the reflow furnace. Then, it is re-introduced into the reflow furnace.

In addition, the heat recovery unit includes a heat exchanger, the condenser, the metal oxide catalyst, the adsorption filter, the hepa filter, and the blower in a bonnet part that is an upper part of the reflow. The first nonwoven fabric filter, the second nonwoven fabric filter, the roll-to-roll dust collector, the low temperature plasma reactor, and the medium filter are located in the section.

The second air purification device is installed in each bonnet part at both ends of the reflow upper conveyor and includes a condenser. One third kit chamber has a medium filter, a low-temperature plasma reactor, or an ozone generator. The metal oxide catalyst, the adsorption filter, the hepa filter and the blower are sequentially mounted.

The metal oxide catalyst may be a single metal oxide or a mixture of metal oxides, and the amount of the metal oxide catalyst may be adjusted within a space velocity of 10,000 to 20,000 hr ⁻¹ . The form is any one of a honeycomb, pellet, and corrugate type.

Further, the intake air amount in the heat recovery unit is adjusted between 1 to 4 m ³ / min, the intake air amount by the purification unit, characterized in that it is adjusted between 1~8m ³ / min.

The volume ratio of the metal oxide catalyst and the adsorption filter included in the first air purification device is 1: 2, and the volume ratio of the metal oxide catalyst and the adsorption filter included in the second air purification device is It is characterized by being 2: 1.

Therefore, the integrated reflow system incorporating the heat recovery device and the air purification device of the present invention condenses the gas-liquid state flux using a condenser, and then filters and traps it with a roll-to-roll dust collector. Because it collects and removes it completely, it prevents the flux from adhering to the reflow panel heater, thereby preventing the defective product of the printed circuit board due to the flux falling from the panel heater and improving the heat transfer effect of the panel heater. Thus, the amount of energy (electric power) consumption can be reduced first. As a result, the panel heater cleaning cycle starts once a month
It can be extended significantly once a year, preventing reflow operation interruption due to cleaning, and improving productivity.

In addition, the integrated reflow system of the present invention does not require a fume management system that must be cleaned once a year, and it saves cleaning costs and guarantees the health of workers from toxic flux. There is an advantage that you can.

In addition, the flux removal can not only improve the efficiency of decomposition and removal of bad odors and volatile organic compounds in the plasma reactor of the air purification device, but also clean the electrode plate of the plasma reactor from time to time. This eliminates the inconvenience, and extends the life of metal oxidation catalysts, activated carbon, and various filters from the existing 3-4 months to a period of more than one year. Therefore, there is an advantage that operation interruption due to cleaning of the electrode plate of the plasma reactor is prevented, and maintenance costs are reduced by extending the life of various catalysts, activated carbon and filters.

In addition, the amount of heat contained in the high-temperature polluted air discharged from the reflow is recovered and re-introduced into the reflow furnace, so that the amount of reflow energy and power consumption can be reduced secondarily. be able to. At the same time, since the temperature is maintained at 40 ° C. or higher at the reflow bonnet site, the performance of the metal oxide catalyst is further improved, and the effect of further decomposing pollutants such as volatile organic compounds by ozone is further increased.

In addition, the built-in reflow built-in air purifier completely inhales and purifies bad odors and volatile organic compounds leaking from the inlet and outlet of both reflow conveyors, creating a comfortable indoor environment. , It has the advantage of improving the concentration of work by simultaneously solving the health and headache problems of workers.

In the integrated reflow system which concerns on this invention, it is a conceptual diagram of the heat recovery of a heat recovery part, and a real-time air purification process. In an integrated reflow system concerning the present invention, it is the composition, arrangement, and process drawing of a heat recovery part. In the integrated reflow system which concerns on this invention, it is a structure schematic diagram of the condenser of a heat recovery part. In the integrated reflow system which concerns on this invention, it is a structure schematic diagram of the roll-to-roll dust collector of a heat recovery part. In the integrated reflow system which concerns on this invention, it is a structure schematic diagram of the low temperature plasma reactor of a heat recovery part. In the integrated reflow system which concerns on this invention, it is a structure, arrangement | positioning, and process drawing of a purification | cleaning part. It is a photograph of the flux removal effect in polluted air by the roll-to-roll dust collector of the integrated reflow system which concerns on this invention. This is a photograph of product failure of the PCB board due to the flux falling on the panel heater. It is a reduction graph of the power consumption of a reflow system by application of a heat recovery device.

The terms and words used in this specification and in the claims should not be construed in a normal or lexicographic sense, but the inventor shall make his or her invention in the best possible way. For the purpose of explanation, it should be construed in the meaning and concept consistent with the technical idea of the present invention in accordance with the principle that the concept of terms can be appropriately defined.

Accordingly, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent the technical idea of the present invention. It should be understood that, at the time of filing, there can be various equivalents and variations that can be substituted.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that in the drawings, the same components or parts are denoted by the same reference numerals as much as possible, and in the description of the present invention, specific descriptions regarding such known functions or configurations are not provided. In order not to obscure the subject matter of the present invention, it is abbreviated.

The integrated reflow system incorporating the heat recovery device and the air purification device of the present invention is a heat recovery device that recovers high-temperature heat from the contaminated air discharged from the reflow furnace (10) and the contaminated air that has passed through the heat recovery device in real time. A heat recovery part (100) composed of a first air purification device to be purified and re-introduced into the reflow furnace (10), and an inlet part (30) and outlet part (40) on both sides of the reflow conveyor (20) And a purification unit (200) including a second air purification device that purifies polluted air discharged from the room in real time and discharges the air into the room. These heat recovery unit (100) and purification unit (200) Built together in one reflow system.

FIG. 1 shows the concept of heat recovery by a heat recovery unit and real-time air purification processing in an integrated reflow system according to the present invention. Contaminated air of about 190 ° C. discharged from a reflow furnace (10) is first heated. After passing through the exchanger (110), it is cooled to about 80-90 ° C, and this is cooled again at about 60-70 ° C using a heat sink (Heat Sink) type condenser (120) and contained in the contaminated air After condensing the gas-liquid (fog) flux, the fine dust and the condensed flux are completely removed by the roll-to-roll dust collector (140) of the first air purifier. Then, the bad odor and volatile organic compounds in the polluted air from which the flux has been removed are completely purified in real time by the first air purifier, and then the hot polluted air discharged from the reflow furnace (10). After exchanging heat using, re-inject into the reflow furnace (10).
At this time, the air purified by the first air purification device is maintained at about 65 to 70 ° C., and heat exchange is performed to about 110 ° C. by high-temperature contaminated air of about 190 ° C. from the heat exchanger (110). This is the principle of re-injection into the reflow furnace (10) after raising.

In the existing environment, high-temperature polluted air is discharged to the outside as it is without a separate process for heat recovery, so that reflow energy and power consumption are serious. However, the temperature of the panel heater is kept uniform by the convection phenomenon by using the heat recovery apparatus as in the present invention and re-injecting the purified air raised to about 110 ° C. into the reflow furnace (10). The power consumption of reflow can be greatly reduced by 10% or more.

Heat recovery part of integrated reflow system

FIG. 2 shows the configuration, arrangement, and process diagram of the heat recovery unit (100) of the integrated reflow system according to the present invention. A heat exchanger (110) and a condenser (120 ), A metal oxide catalyst (170), an adsorption filter (180), a hepa filter (182), and a blower (190). The first non-woven filter (131) and the second non-woven filter ( 132), a roll-to-roll dust collector (140), a low temperature plasma reactor (150) and a medium filter (160) are located.

High-temperature contaminated air of about 190 ° C discharged from the integrated reflow furnace (10) exchanges heat with the purified air through the heat exchanger (110), and the heat is exchanged into the condenser (120) shown in Fig. 3. Be transported. At this time, the contaminated air transferred to the condenser (120) is cooled to 80 to 90 ° C. in the heat exchange process, and is cooled again by the heat sink (122) type condenser (120) including the fan (124), It is preferable to condense the flux in the state of gas-liquid (salt liquid) and cool it to about 60-70 ° C.

The relatively large particles in the flux that has passed through the condenser (120) are first filtered from the first non-woven fabric filter (131), and the fine dust and the remaining small particle flux are the same as those shown in FIG. Completely collected and removed by a two-roll dust collector (140). By doing so, it prevents the remaining fine dust or flux from adhering to the subsequent low-temperature plasma reactor (150) and metal oxide catalyst (170), and decomposes / degrades bad odors and volatile organic compounds. Not only can the removal effect be improved almost completely, but the troublesomeness of having to clean the electrode plates (151, 152) of the low temperature plasma reactor (150) from time to time is eliminated, and the metal oxide catalyst (170 ), The life of various filters including the adsorption filter (180) and the hepa filter (182) can be extended for a period equivalent to one year or more.

The roll-to-roll dust collector (140) includes a dust collection filter (142), a drive unit (144), a driven unit (146), and a collection unit (148). The dust collection filter (142) is wound in a roll shape with a certain width, and is attached little by little by the driving unit (144) while being mounted on a driven shaft (not shown) of the driven unit (146). The fine dust, smoke, dust, soot, and flux are filtered and collected through the collecting part (148), and are collected by proceeding to the driving part (144). At this time, the traveling speed of the dust collecting filter (142) can be adjusted between 2 and 10 cm / sec.

Low temperature plasma reactor (150) generates bad odors and volatile organic compounds contained in contaminated air that has passed through a roll-to-roll dust collector (140) using a DBD (Dielectric Barrier Discharge) method and generates plasma at room temperature Decompose using the generated ozone. As shown in FIG. 5, the low-temperature plasma reactor (150) is supplied with a booster (154) that boosts the voltage of power supplied from the power supply unit (155) and a power source boosted by the booster (154), respectively. The first electrode plate (151) and the second electrode plate (152) are preferably configured. It is preferable that the first electrode plate (151) and the second electrode plate (152) are sequentially crossed and configured so that air can flow and pass through the space between the electrode plates. In this case, it is preferable that the first electrode plate (151) and the second electrode plate (152) are usually arranged in an intersecting manner by about 3 to 10 steps. On the other hand, the booster (154) is preferably boosted with a high voltage in the range of 10 to 20 KV.

Secondly, the air that has passed through the low temperature plasma reactor (150) can contain bad odors and fine dust that can be generated in the process of decomposing volatile organic compounds. Remove again completely with the filter (160).

The metal oxide catalyst (170) uses active oxygen after decomposing residual ozone contained in contaminated air that has passed through the low-temperature plasma reactor (150) or ozone generator (not shown) with active oxygen. Then, the unreacted volatile organic compound that was not decomposed by the low temperature plasma reactor (150) is decomposed. In this case, examples of the catalyst for decomposing ozone include platinum, Cr oxide, Al oxide, Co oxide, Cu oxide, Mn oxide, metal Pd, or Pd compound, Among them, it is preferable to use a metal oxide. These metal oxide catalysts include MnO ₂ , NiO, CoO, Fe ₂ O ₃ , V ₂ O ₅ , AgO ₂ and the like. Moreover, not only a single metal oxide but also a mixture of a plurality of metal oxides can be used. For example, it can be used in the form of MnO ₂ —CuO, MnO ₂ —AgO ₂ , Mn ₂ O ₃ —TiO ₂ and NiO—CoO—AgO ₂ . The metal oxide catalyst may be a honeycomb type, a pellet type, or a corrugate type.

Therefore, the metal oxide catalyst (170) can be further decomposed by removing residual volatile organic compounds that have not been decomposed by the low-temperature plasma reactor (150) in the previous stage, and of course eliminating exhaust ozone. Is simultaneously performed to reduce the ozone concentration in the finally discharged air. At this time, the volume of the metal oxide catalyst (170) (the amount of metal oxide catalyst used) should be determined so that the space velocity is between 10,000 and 20,000 (hr ^-1 ) with respect to the treatment air volume (flow rate). Is preferred. In this case, the space velocity is defined by the following equation.

Space velocity (hr ^-1 ) = flow rate (m ³ / hr) ÷ catalyst volume (m ³ )

Next, the adsorption filter (180) is a contaminant in the air that has passed through the metal oxide catalyst (170), that is, carbon monoxide (CO) generated as a by-product in the decomposition process of exhaust ozone or the volatile organic compound. ) And carbon dioxide (CO2). In this case, the adsorption filter (180) can be configured to include honeycomb type activated carbon or pellet type activated carbon.

On the other hand, since the heat recovery unit (100) re-injects purified air into the reflow furnace (10), the volume ratio of the metal oxide catalyst (170) and the adsorption filter (180) should be 1: 2. Is preferred.

Further, the adsorption filter (180) may further include a hepa filter (182), and the hepa filter (182) removes 99.97% or more of fine particles having a size of 0.3 μm or more, and then performs a purification process. The injected air is reintroduced into the reflow furnace (10). At this time, the temperature of the air after purification is about 65 to 70 ° C., but this is exchanged by using high-temperature contaminated air of about 190 ° C. discharged from the reflow furnace (10), and about 110 ° C. The temperature of the panel heater is re-introduced into the reflow furnace (10) and then the panel heater temperature is maintained uniformly due to the convection phenomenon. Savings can be made on a regular basis.

On the other hand, the nonwoven fabric filter (131), the roll-to-roll dust collector (140), the low temperature plasma reactor (150), and the medium filter (160) located in the lower stage of the reflow in the heat recovery section (100) Produced so that it can be attached to one kit chamber, and adopting a sliding method, the kit chamber can be easily taken out of the reflow. In this case, the replacement work of the first nonwoven fabric filter (131), the dust collection filter (142) of the roll-to-roll dust collector (140), and the medium filter (160) is further facilitated. Then, the fume management system at the bottom of the existing reflow is removed, and the first kit chamber is positioned there.

In addition, the metal oxide catalyst (170), adsorption filter (180) and hepa filter (182), and blower (190) located in the upper stage of the reflow in the heat recovery unit (100) are mounted in one second kit chamber. If the catalyst and filter are changed, the bonnet cover at the upper stage of the reflow can be opened and replaced easily.

On the other hand, when the first non-woven filter (131) located in the lower stage of the reflow, the dust filter (142) of the roll-to-roll dust collector (140), the medium filter (160), etc. are replaced, FIG. As shown in Fig. 5, the contaminated air that has passed through the condenser (120) is bypassed using a T-pipe and transferred directly to the second non-woven filter (132). Then, again using the T pipe, the metal oxide catalyst (170), the adsorption filter (180), and the hepa filter (182) of the second kit chamber located in the upper stage of the reflow are directly passed. In this case, there is an advantage that the reflow operation is not interrupted even when the catalyst and various filters are replaced.

Intake air amount by the heat recovery unit from (100) blower (190) is about 2m ³ / min, preferably from about 1 to 4 m ³ / min.

The operation procedure of the heat recovery unit (100) is as follows.

Normal operation: suction from reflow oven → heat exchanger → condenser → first kit chamber (first non-woven filter-roll-to-roll dust collector-low temperature plasma reactor-medium filter) → second kit chamber (Metal oxide catalyst-adsorption filter-hepa filter-blower) → heat exchanger → put into the reflow furnace.

When changing the filter: Suction from the reflow oven → Heat exchanger → Condenser → Bypass (T piping) → Second non-woven filter → Second kit chamber (metal oxide catalyst-adsorption filter-Hepa filter-Bull lower) → Heat Exchanger → Input into the reflow furnace.

Integrated reflow purification section

Arrangement and role of each component of the purification unit (200) with a built-in second air purification device that purifies bad odors and volatile organic compounds discharged from both side entry / exit parts (30, 40) of the reflow conveyor (20) The process will be described.

As shown in FIG. 6, the second air purification device of the purification unit (200) is installed at both bonnet parts at the upper end of the reflow and discharged from the inlet / outlet parts (30, 40) of the conveyor (20). It is preferable to purify and treat malodors and volatile organic compounds. At this time, the second air purification device includes a condenser (210), a medium filter (220), a low-temperature plasma reactor (230), an ozone generator (not shown), a metal oxide catalyst (240), an adsorption Includes filter (250), hepa filter (252), blower (260), etc.

Contaminated air discharged from both of the integrated reflow conveyors (20) has a temperature of about 80 to 90 ° C and is cooled by a heat sink type condenser (210) shown in Fig. The flux in the state is condensed and preferably cooled to about 50 to 60 ° C.

The flux that has passed through the condenser (210) is completely collected and removed from the medium filter (220). In this case, the fine dust and flux contained in the contaminated air discharged from both the reflow conveyor (20) are relatively less than the contaminated air discharged from the reflow furnace (10). 220) alone can be effectively removed.

The medium filter (220) is used as a pretreatment filter to physically collect large dusts and the like first, thereby increasing the efficiency of the subsequent purification and decomposition steps.

The contaminated air from which fine dust and flux have been removed by the medium filter (220) is the ozone generated by generating plasma at room temperature from the odorous and volatile organic compounds contained in the contaminated air from the low temperature plasma reactor (230). Use and disassemble.

On the other hand, the structure of the low temperature plasma reactor (230) of the purification unit (200) is the same as that of the low temperature plasma reactor (150) of the heat recovery unit (100), and the booster (154) is in the range of 10 to 20 KV. It is preferable to boost the voltage with a high voltage.

In this case, the malodor and volatile organic compounds contained in the contaminated air discharged from both the reflow conveyor (20) are relatively less than the contaminated air discharged from the reflow furnace (10). It is preferable that the first electrode plate (151) and the second electrode plate (152) are usually arranged in a crossing arrangement of about 3 to 5 stages, and instead of the low temperature plasma reactor (230). An ozone generator may be used.

The metal oxide catalyst (240) decomposes residual ozone contained in the contaminated air that has passed through the low temperature plasma reactor (230) with active oxygen, and then uses the active oxygen to convert the low temperature plasma reactor (230). ) To decompose unreacted volatile organic compounds that were not decomposed in step (b). At this time, the metal oxide catalyst (240) not only completely decomposes residual volatile organic compounds that have not yet been decomposed from the low-temperature plasma reactor (230) of the previous stage, but also removes exhaust ozone. Is simultaneously performed to reduce the ozone concentration in the finally discharged air. The volume and space velocity of the metal oxide catalyst (240) of the purification unit (200), and the type and form of the metal oxide are the same as those of the metal oxide catalyst (170) of the heat recovery unit (100).

The adsorption filter (250) is a filter for producing polluted water in the air that has passed through the metal oxide catalyst (240), that is, carbon monoxide (CO) and carbon dioxide produced as by-products in the decomposition process of exhaust ozone or volatile organic compounds. Adsorb and remove (CO2). In this case, the adsorption filter (250) can be configured to include honeycomb type activated carbon or pellet type activated carbon.

Since the purification unit (200) discharges the purified air into the work chamber, the volume ratio of the metal oxide catalyst (240) and the adsorption filter (250) is preferably 2: 1.

The adsorption filter (250) can further comprise a hepa filter (252), and the hepa filter (252) removes 99.97% or more of fine particles of 0.3 μm or more and then purified air. Is discharged into the room. At this time, the temperature of the air after purification is about 40 to 45 ° C., and the temperature of the workplace is maintained at 25 to 26 ° C. by operating the air conditioner and discharging the air conditioner about 4 times per hour in the summer. 40-45 degrees Celsius air is exhausted indoors, and there is an effect of reducing power consumption when operating the heater.

Medium filter (220), low-temperature plasma reactor (230), ozone generator, metal oxide catalyst (240), adsorption filter (250), hepa filter (located at the bonnet part of the reflow upper stage in the purification section (200) 252), the blower (260) is manufactured so as to be mounted in one third kit chamber, and when replacing the catalyst or the filter, the bonnet cover on the upper stage of the reflow can be opened and replaced easily.

Intake air amount by the blower (260) from the purification unit (200) is about 4m ³ / min, preferably from about 1~8m ³ / min.

The normal operation procedure of the purification unit (200) is as follows.

Normal operation: Conveyor both suction → Condenser → Third kit chamber (medium filter-low temperature plasma reactor or ozone generator-metal oxide catalyst-adsorption filter-hepa filter-blower) → discharged into the room.

In the following, the present invention is illustrated by several examples.

<Example 1> (Temperature reduction effect of contaminated air by a condenser)

1Measurement method of temperature reduction effect

As shown in Fig. 3, the heat sink type condenser is manufactured, and the temperature of the polluted air that has been discharged from the reflow furnace and passed through the heat exchanger is measured at the front stage of the condenser and the rear stage after passing through the condenser. Then, the temperature reduction effect was compared and examined.

At this time, the temperature was measured at an interval of 1 hour after 2 hours of operation, which is the time when reflow reached normal operation, and the amount of air sucked by the blower was 3 m ³ / min.

2 Measurement results of temperature reduction effect of contaminated air

After 1 hour has passed since reflow reached normal operating conditions, the temperature of the contaminated air is about 79.3 ° C in the first stage of the condenser, and it appears at about 58.1 ° C in the second stage after passing through the condenser. It decreased by about 21 ℃.

After operating for 8 hours, the temperature of the contaminated air appears at 85.5 ° C in the former stage of the condenser, and appears at about 63.8 ° C in the latter stage of the condenser, decreasing by about 21.7 ° C.

In general, even if the reflow operation time continues, the temperature of the contaminated air after passing through the condenser is maintained at about 63 ° C., and the temperature decrease width of the contaminated air is kept constant at about 21 ° C. This shows that the gas-liquid flux in the contaminated air is condensed very effectively.

Measurement result of temperature reduction of polluted air by condenser

<Example 2> (Flux removal effect by roll-to-roll dust collector)

1 Measuring method of flux removal effect

Using the roll-to-roll dust collector shown in FIG. 4, the removal effect of the flux contained in the contaminated air generated during reflow soldering was visually measured.

The PCB board coated with solder paste is charged into the reflow, and the contaminated air generated when the solder paste melts in a furnace at about 250 ° C is condensed with a condenser as in <Example 1>. After that, it was collected on the filter 1 surface of a roll-to-roll dust collector.

In the measurement experiment of the flux removal effect, the number of PCB plates inserted was varied, and the degree of collection on one surface over the fifth order was measured.

At this time, the performance test was conducted on the flux removal effect with the intake air amount set to 3 m ³ / min, which is the same condition as in <Example 1>.

Experimental conditions for measuring the flux removal effect generated by reflow

2 Measurement result of flux removal effect

As shown in Fig. 7, as the number of PCBs coated with solder paste increases, more and more flux is collected on the filter surface of the roll-to-roll dust collector. ing. Further, since the gas-liquid flux is condensed in advance by the condenser, it can be seen that the flux is completely collected by the filter.

As in the fifth experiment, even if the amount of the solder paste is used at about 976 gr, a differential pressure is not generated by the filter to which the flux is adhered, and the air flow appears well.

It is possible to know that the maximum amount of solder paste can be processed up to 1,000 gr with one filter of a roll-to-roll dust collector, and it can be used for up to 24 hours with one filter on an industrial site.

In this way, by removing the flux by the roll-to-roll dust collector and preventing the flux from adhering to the panel heater in the reflow furnace, the flux falls on the PCB board as shown in FIG. It is possible to prevent the product defect phenomenon that occurs.

<Example 3> (Reflow power consumption reduction effect)

1Measurement method of power consumption by applying heat recovery device

As shown in the schematic diagram of the heat recovery apparatus in FIG. 1, the air purified in real time by the air purification apparatus using the high-temperature contaminated air of about 190 ° C. discharged from the reflow furnace is converted into 110 by the heat exchanger. After raising the temperature to about ℃, it was re-introduced into the reflow furnace to reduce the power consumption of reflow.

At this time, the intake air volume was 3 m ³ / min, which is the same condition as the industrial site, and the reflow power consumption before and after application of the heat recovery device was comparatively measured for 4 hours using an integrating wattmeter.

2Reflow power consumption measurement results

As shown in Fig. 9, the power consumption of reflow was about 50Kwh before the heat recovery device was applied, but it decreased to 44.6Kwh after the application, and the power of about 5.4Kw decreased for 4 hours. This shows a power saving effect of approximately 11%.

Therefore, when this is converted into a monetary amount, it is possible to save about 1,774,000 won annually only by the effect of applying the heat recovery device.

Power saving (day): 1.35Kw x 24hr = 32.4Kwh

32.4Kwh x 150won / Kwh = 4,860won / day

Electricity saving (month): 4,860 won / day x 30 days = 145,800 won / month

Cost of annual power saving: 4,860 won / day x 365 days = 1,773,900 won

<Example 4> (Removal effect of volatile organic compounds by air purifier)

1. Measuring method of removal effect of volatile organic compounds (VOCs)

A performance test on the removal efficiency of volatile organic compounds was conducted at the indoor environmental analysis center of Seoul National University.

At this time, the volatile organic compound decomposition / removal performance test was performed in a low-temperature plasma reactor of the air purifier at an applied voltage of 15 KV, an air volume of 3 m ³ / min, and a space velocity of 17,000 hr ⁻¹ .

2. Measurement results of the removal effect of volatile organic compounds (VOCs)

The removal efficiency of total volatile organic compounds (Total VOCs) is as follows. In other words, the concentration of the total volatile organic compounds in the polluted air discharged from the reflow furnace is about 77931.3 μg / m ³ , whereas the concentration of the total volatile organic compounds is 205.6 μg after passing through the air purification device. / m significantly decreased by about ^3, shows a 99.7% higher removal efficiency. In particular, 205.6μg / m ³ is the concentration of total volatile organic compound after the air purifier is stopped about half a well below the indoor standard value (500μg / m ^3).

And after processing of an air purifier, benzene does not appear at all among five typical volatile organic compounds, toluene is 18.6 μg / m ³ , ethylbenzene is 10.7 μg / m ³ , and xylene is 13.3 μm. [mu] g / m ^3, styrene is manifested by decreased to about 0.8 [mu] g / m ^3, a representative five volatile organic compounds (benzene, toluene, ethylbenzene, xylene, styrene) are also effectively removed It shows that the number is much lower than the room reference value.

Removal effect of volatile organic compounds by air purifier

<Example 5> (Ozone removal effect by metal oxide catalyst)

1Measurement method of ozone removal effect

After passing through the initial ozone concentration generated in the low temperature plasma reactor of the air purification device and the metal oxide catalyst of the air purification device, the ozone (exhaust ozone) concentration was measured.

At this time, the applied voltage was set to 15 KV, the air volume was set to 3 m ³ / min, and the space velocity was set to 17,000 hr ⁻¹ in the low temperature plasma reactor of the air purifier, and the ozone concentration was measured.

2Measurement results of ozone removal effect

The initial ozone concentration generated in the low-temperature plasma reactor is about 40 ppm. On the other hand, after reacting with the metal oxide catalyst and decomposing volatile organic compounds, the ozone concentration in the most exhausted air is about Appears at around 0.015 ppm, indicating an ozone removal efficiency of 99.96%. This is within the allowable ozone concentrations in Korea and the United States.

-Korea ozone concentration tolerance: 1 hour average 0.1 ppm, 8 hour average 0.06 ppm

-US ozone concentration tolerance: 8ppm / 40hours 0.1ppm, 15min 0.3ppm

The present invention can be applied to various fields. In other words, not only the electronics and semiconductor markets such as the soldering process, but also the demand for air purification devices that decompose and deodorize volatile organic compounds, pollutants and odors emitted from dyeing, printing, painting and plating processes, etc. Is expected to increase.

Prospects for purification facilities in general hospitals or medical facilities are also increasing due to the improvement of quality of life, so the prospects are very inspiring, and universities and research laboratories that use toxic chemicals, It can also be applied in a factory washing room.

In the case of an electronic component manufacturing process, productivity can be improved by solving the headache problem caused by gas generated by ink application.

The present invention can also be applied to purification treatment of volatile gases such as ammonia and methane generated from a pig barn.

It is very effective for purification treatment of flux, toxic gas and volatile organic compounds that are generated when burning soot and fuel generated by soot of automobiles in tunnels.

At the present time, smoking cessation facilities are becoming increasingly widespread due to the government's strong smoking cessation policy. Can be processed.

The preferred embodiment is disclosed in the drawings and specification. Certain terminology is used herein for the purpose of describing the present invention merely and is used for limiting the meaning and scope of the present invention described in the claims. It was n’t. Accordingly, it should be understood by those having ordinary skill in the art that various modifications and other equivalent embodiments are possible. The true technical protection scope of the present invention is defined by the technical idea of the appended claims.

100: Heat recovery unit
110: Heat exchanger
120, 210: Condenser
122: Heat Sink
124: Fan
131, 132: First and second nonwoven fabric filters
140: Roll-to-roll dust collector
150, 230: Low temperature plasma reactor
160, 220: Medium filter
170, 240: Metal oxide catalyst
180, 250: Adsorption filter
182, 252: Hepa filter
190, 260: Blower
200: Purification Department

Claims (12)

In the reflow system,
A heat recovery device that recovers high-temperature heat from the contaminated air discharged from the reflow furnace (爐) (10), and the contaminated air that has passed through the heat recovery device is purified in real time and re-entered into the reflow furnace (10). The air recovery unit (100) including the first air purifying device that cleans the contaminated air discharged from the inlet (30) and outlet (40) on both sides of the reflow conveyor (20) in real time, And a purification unit (200) including a second air purification device that discharges to (50), and an integrated reflow system incorporating the heat recovery device and the air purification device.
The heat recovery device of the heat recovery unit (100) includes a heat exchanger (110) and a condenser (120),
Contaminated air discharged from the reflow furnace (10) passes through the heat exchanger (110),
After cooling to 80 to 90 ° C., after passing through the condenser (120), cooling to 60 to 70 ° C., and condensing the gas-liquid (liquid) state flux in the contaminated air, the first air The integrated reflow system incorporating the heat recovery device and the air purification device according to claim 1, wherein the reflow system is transferred to the purification device.
The integrated reflow system according to claim 2, wherein the condenser (120) includes a heat sink (122) and a fan (124).
The first air purification device includes a first non-woven fabric filter (131) and a roll-to-roll dust collector (140) for removing condensed flux through a condenser (120), the roll-to- The bad smell in the air that passed through the dust collection filter (142) of the roll dust collector (140) and the low temperature plasma reactor (150) that removes volatile organic compounds and the bad smell in the air that passed through the low temperature plasma reactor (150) A medium filter (160) for removing fine dust generated in the process of decomposing volatile organic compounds is sequentially attached to one first kit chamber, and the first kit chamber is pulled out. The integrated reflow system with a built-in heat recovery device and air purification device according to claim 1, wherein a sliding method is applied for mounting.
The first air purification device includes a metal oxide catalyst (170) that removes residual ozone contained in air that has passed through the first kit chamber, and air that has passed through the metal oxide catalyst (170). An adsorption filter (180) and a hepar filter (182) for adsorbing and removing carbon monoxide and carbon dioxide produced as by-products in the decomposition process of exhaust ozone and volatile organic compounds in the inside, and the adsorption filter (180), The heat according to claim 4, wherein a blower (190) for transferring the air that has passed through the hepar filter (182) to a reflow furnace (10) is sequentially attached to one second kit chamber. Integrated reflow system with built-in recovery device and air purification device.
In the first kit chamber, any one of the first nonwoven fabric filter (131), the dust collection filter (142) of the roll-to-roll dust collector (140), and the medium filter (160) When the above is changed, the contaminated air that has passed through the condenser (120) does not pass through the first kit chamber, but bypasses the second nonwoven fabric filter (132) separately. The integrated reflow system with a built-in heat recovery device and air purification device according to claim 5, wherein the condensed flux is removed and then transferred to the second kit chamber.
The air that has been cooled to 65 to 70 ° C. through the first air purification device is purified by using the contaminated air at 190 ° C. discharged from the reflow furnace (10) through the heat exchanger (110). The integrated reflow system with a built-in heat recovery device and air purification device according to claim 2, wherein the temperature is raised to 110 ° C and then reintroduced into the reflow furnace (10).
The heat recovery unit (100) includes a heat exchanger (110), a condenser (120), a metal oxide catalyst (170), an adsorption filter (180), and a hepa filter (182) in the bonnet portion that is the upper stage of the reflow. And the blower (190) is arranged,
The first non-woven filter (131), the second non-woven filter (132), the roll-to-roll dust collector (140), the low temperature plasma reactor (150) and the medium filter (160) are located in the lower part of the reflow. The integrated reflow system including the heat recovery device and the air purification device according to claim 1.
The second air purification device of the purification unit (200) is installed in each bonnet part at both ends of the reflow upper conveyor (20), includes a condenser (210), and includes a medium filter (220 in one kit chamber 3. ), Low temperature plasma reactor (230) or ozone generator, metal oxide catalyst (240), adsorption filter (250), hepa filter (252) and blower (260) The integrated reflow system according to claim 1, wherein the heat recovery device and the air purification device are incorporated.
The metal oxide catalyst is a single metal oxide or a mixture of metal oxides,
The amount of the metal oxide catalyst is adjusted within a space velocity of 10,000 to 20,000 hr ⁻¹ , and the form of the metal oxide catalyst is:
10. The integrated reflow system incorporating a heat recovery device and an air purification device according to claim 5 or 9, wherein the integrated reflow system is one of a honeycomb type, a pellet type, and a corrugate type.
The intake air volume from the heat recovery unit (100) is adjusted between 1 to 4 m ³ / min, and the intake air volume from the purification unit (200) is adjusted between 1 to 8 m ³ / min. The integrated reflow system according to claim 1, wherein the heat recovery device and the air purification device are incorporated.
  The volume ratio of the metal oxide catalyst (170) and the adsorption filter (180) included in the first air purification device is 1: 2, and the metal oxide catalyst (240) included in the second air purification device. 2. The integrated reflow system with a built-in heat recovery device and air purification device according to claim 1, wherein the volume ratio of the filter and the adsorption filter (250) is 2: 1.