JP2002004187A - Method and system for feeding cellulose fibrous material to treatment vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved system and method for feeding a slurry of a finely pulverized cellulose fibrous material to the top of a treatment vessel such as a digester. SOLUTION: A chip slurry subjected to steaming treatment is pressurized with one or plural units of slurry pumps 251 and 251' located in a position at least 30 feet below the top of the treatment vessel 11 and pressurized to at least about 10 bars (gauge) pressure. A return line 235 from the top of the digester 11 may, but need not necessarily, be operatively connected to the one or plural units of slurry pumps 251 and 251' and if connected to the pumps 251 and 251', the liquid in the return line 235 may be cooled to a temperature at which the liquid will not flash during handling. Recirculation loops may be established associated with one or all of the slurry pumps 251 and 251' to facilitate startup. A static flow splitter may provided to split the flow from the last pump 251' to the two or more digesters 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for supplying a comminuted cellulose fiber material to a treatment tank such as a continuous digester. The present invention simplifies and dramatically reduces the number of devices required compared to the prior art.

[0002]

BACKGROUND OF THE INVENTION U.S. Pat. Nos. 5,476,572, 5,622,598, 5,635,025 and 5,763.
No. 6,418 provided the first real innovation in the technology of supplying comminuted cellulosic fibrous material to a treatment tank for more than 40 years. These patents and applications are described in Ahlstrom Machinery In, Glens Falls, NY, specifically for feeding to digesters using slurry pumps.
c.) is sold in bulk at the low level (LO-LEVEL)
Several embodiments of the (registered trademark) supply device are disclosed. As described in these patents and applications, using such a pump to supply slurry to a high-pressure transfer device dramatically reduces the required equipment complexity and physical size, Increased ease of operation and maintenance. Prior art devices using high pressure transfer devices, such as the high pressure feeders sold by Ahlstrom Machinery, however, do not use such pumps and therefore have a
It was virtually no different from the equipment sold and built since the 940s and 1950s.

[0003]

SUMMARY OF THE INVENTION The present invention is directed to further dramatic improvements to the methods and apparatus disclosed in the above patents and applications. The present invention virtually eliminates the need for a transfer device such as a high pressure feeder, and instead uses a high pressure pump device to directly transfer the slurry of the comminuted cellulose fiber material to the digester. It is.

[0004] In order to produce a chemical pulp by reacting a comminuted cellulosic fiber material with a pulp-forming agent, 140 to 1
A temperature of 80 ° C is required. Commercial chemical pulp production typically involves at least about 10 to 10 hours because the aqueous drug solution used to treat the cellulosic material boils at such temperatures.
It is performed in a pressure vessel under a pressure of bar (gauge) (about 150 pounds per square inch (gauge)). To maintain this pressure, special equipment must be used to ensure that the pressure is not lost when the cellulosic material is introduced into the pressure vessel, especially when performing a continuous pulp manufacturing process. In the prior art, this is done using equipment known in the art as a "high pressure feeder". The feeder is a specially designed device that has a pocket-structured rotor that serves to transfer the slurry of the cellulosic material from low pressure to high pressure and at the same time acts as a valve to prevent loss of pressure. This complex and expensive device has long been used to transfer milled cellulosic material into
Usually at high temperatures, it has been considered an essential component, especially for introduction into continuous digesters.

In accordance with the present invention, construction of a pulp mill is provided because an alternative is provided to a high pressure feeder, which has been considered essential for continuous digestion for over forty years. It is greatly simplified.

According to one aspect, an apparatus for producing a chemical cellulose pulp from a comminuted cellulosic fibrous material such as wood chips comprises the following components: A steam treatment tank for steaming the milled cellulose fiber material to remove air therefrom; an inlet for the milled cellulose fiber material slurry at the top; A pressure-raising / transfer means for pressurizing the cellulose slurry from the steam processing tank and transferring it to the inlet of the processing tank, comprising one or more high-pressure slurry pumps installed below the top of the processing tank. It is a step-up / transfer unit.

[0007] The one or more pumps are formed by connecting first and second high-pressure slurry pumps each having a high-pressure specification and having an inlet and an outlet in series. Preferably, the second pump is connected to the tank during operation, and has a higher pressure specification than the first pump. The slurry pump may be a swirl vane centrifugal pump, a double piston solid pump, or may be capable of raising a slurry having a relatively high concentration of solids to a pressure of at least about 5 bar (gauge) (in one or more stages). A similar conventional pump device may be used. The pressurization and transfer may be performed by one or more eductors of conventional construction driven by a high pressure fluid source such as provided by a conventional centrifugal pump.

[0008] One of the common units of measure that indicates the relative amount of solids in a slurry containing solids and liquids is the "liquid / solid ratio". In the present application, this ratio is the ratio of the volume of liquid transferred to the volume of cellulose or wood transferred.
Typical conventional centrifugal liquid pumps are limited to pumping liquids having a maximum solids content of 3%. This 3% solids content is about 3% in liquid / solid ratio.
Equivalent to 3. In the slurry pump of the present invention, the liquid / solid ratio of the pumped slurry is usually 2 to 10, preferably 3 to 7, and most preferably 3 to 6. In other words, the slurry pump of the present invention transfers a slurry having a solids content that is much greater than can be handled by conventional pumps.

From the top of the processing tank, a liquid return line containing the liquid separated from the slurry at the top of the processing tank (preferably a continuous digester) can be provided. This liquid line can be connected directly or indirectly to the inlet or outlet of the slurry pump during operation. Preferably, the liquid return line is connected to pressure reducing means for reducing the pressure of the liquid in the return line before the liquid is sent to the inlet or outlet of the slurry pump. The means for reducing pressure may take a variety of forms, such as a flash tank and / or pressure control valve in the return line, or other conventional structures that effectively reduce the pressure of the liquid in the line while not adversely affecting the liquid. Can be taken. When using a flash tank, the liquid outlet from the flash tank is connected to the inlet of the first slurry pump, and the steam generated in the flash tank can be used in the steam treatment tank.

[0010] Alternatively, the pressure drop can be, or can be avoided, by using an eductor that uses a high pressure return line liquid as the source of pressure liquid. The eductor can transfer the slurry to the digester in lieu of or in conjunction with one or more slurry pumps or other equipment.

[0011] The conventional chute is preferably connected between the steam treatment tank and the at least one slurry pump, as well as other optional components. The steam treatment tank is disposed on a chute, and the chute is disposed on the at least one slurry pump. The at least one slurry pump is typically provided at least 30 feet (about 10 meters) below the top of the digester, usually about 50 feet (about 15 meters) or more.

When eliminating the high-pressure transfer device, it is desirable to use another mechanism having one of the functions of the high-pressure transfer device, that is, a function of preventing depressurization when an abnormal condition occurs. The high pressure transfer device typically prevents backflow of liquid from the digester to the feed system. It is preferable that the depressurization preventing means of the present invention is different from the at least one slurry pump. However, under certain circumstances, the inlet to the slurry pump and the outlet from the slurry pump may be configured to have a depressurization preventing function.
The means for preventing depressurization may be provided with an automatic shut-off valve in each of the slurry conduits for transferring the slurry from the pump to the top of the processing tank and to the return line from the processing tank. And
A conventional controller is attached to the shut-off valve, and the shut-off valve is operated according to the pressure detected by a pressure sensor provided in a slurry conduit for supplying slurry to the top of the processing tank. The anti-pressure relief means may include a check valve in the slurry conduit and / or other various valves, tanks, sensors,
It may be a controller or a fluid, mechanical or electrical device capable of performing a pressure relief function.

The device may include means for increasing the flow of liquid at the inlet to the second slurry pump or any pump or transfer device, for example, a liquid containing liquid at a pressure less than or equal to the pressure at the inlet of the second slurry pump. A line, a conduit between the liquid line and the pump inlet, and a liquid pump in the conduit may also be provided. The liquid line may be a return line from the processing tank, and the conduit may be directly connected to the return line. The liquid return line may be connected to the flash tank as described above, and the conduit may be connected to the flash tank liquid outlet.

According to another aspect of the present invention, there is provided a method of supplying a comminuted cellulosic fibrous material to the top of a processing vessel. The method includes the following steps. That is, (a)
Steaming the cellulose material to degas the cellulose material and heating it; (b) slurrying the cellulose material with a cooking liquor to produce a slurry of the liquid and the cellulose material; (c) the slurry To raise the slurry to a pressure of at least about 5 bar (gauge) at the bottom (e.g., at least 30 feet, preferably at least 50 feet) below the top of the treatment vessel, and treat the pressurized cellulosic material. Transferring to the top of the tank. Incidentally, this pressure raising step is performed on the slurry using one or more high-pressure slurry pumps.

[0015] The method further includes the following steps. (D) returning the liquid separated from the slurry at the top of the processing tank to the at least one pump;
(E) detecting the pressure of the slurry being transferred to the top of the processing tank, and if the detected pressure drops below a predetermined value,
Blocking the flow of slurry to the top of the processing tank and the return of liquid from the top of the processing tank. Further, (f) a step may be provided in which the liquid returned when performing step (d) is flushed to generate steam, and the steam is used for performing step (a).

In yet another aspect, the concept of transferring a slurry of chips is provided where the chips are introduced into a mill,
That is, it is used as far back as the wood yard. Conventional pulp mills supply cellulosic material, usually hardwood and softwood, but as noted above, other forms of cellulosic material are also handled in a wide variety of ways. These cellulosic materials include, for example, sawdust, chips, logs, pruned long trees (i.e., long trees), or untouched trees (i.e., "hole trees"). Depending on the cellulose source of the "supplied wood",
Wood is usually subdivided into chips for handling and processing in the pulp manufacturing process. For example, chips obtained by using a device known as a "chipper" to grind a long tree or log into small chips are usually stored in a chip outdoor storage area or a chip silo. Acceptance, handling,
Storage takes place in a pulp mill area called a "wood yard." From the wood yard, chips are usually transported to a pulp mill suitable for starting the pulp manufacturing process.

In a conventional wood yard, chips are stored in silos, from which the chips are discharged to a conveyor, usually using a rotary or vibratory silo discharge device. The conveyor is typically a belt conveyor that receives chips and transfers them to a pulp processing tank. This conveyor is usually long, as the wood yard is usually at a distance from the pulp making tank. This conveyor can be as long as half a mile.
In addition, Ahlstrom Machinery
chinery) and U.S. Patent Nos. 5,476,572; 5,622,598; 5,635,02.
No. 5,766,416 discloses a processing system that does not use a LO-LEVEL (registered trademark) supply device, and supplies chips to an inlet of a first pulp production tank. To do so, the conveyor must typically be run at least 100 feet high. These conveyors and the structures that support them are extremely expensive and represent a significant portion of the cost of the digester feed system.

According to another aspect, the concept of transferring a slurry of chips is used going back to a wood yard.
A preferred embodiment of the present invention provides a method of transferring a comminuted cellulosic fiber material to a pulp manufacturing process, the method comprising the following steps. That is, (a) a step of introducing untreated chips into a first tank, (b) a step of introducing a slurried liquid into the first tank to generate a slurry of a cellulose material and a liquid, and (c) the slurry (D) pressurizing the slurry with the pressurizing / slurrying device, and transferring the slurry to a processing tank.

The first tank is usually a chip storage silo or bottle. The bottle preferably has an outlet with a one-dimensional reduction without the use of agitation or vibration, such as the DIAMONDBACK® bottle described in US Pat. No. 5,000,083. is there. The bottle may also have more than one outlet feeding two or more transfer devices. This vessel can be operated at a pressure above atmospheric pressure, for example, between 0.1 and 5 bar. If the vessel is operated at a pressure above atmospheric pressure, some type of pressure shut-off device must be provided at the inlet of the vessel to prevent the pressure from dropping. The device may be a star-type shut-off device, for example, a low pressure feeder sold by Ahlstrom Machinery or an airlock feeder, or a screw-type feeder with sealing capability as described in US Pat. No. 5,766,416.

[0020] The slurried liquor may be from any source available at the pulp mill. For example, fresh water, steam condensate, craft white liquor, black liquor, green liquor,
It may be a sulfite liquor or any other pulp-related liquid. The liquid may be a heated fluid, for example, hot water at a temperature of 50-100 ° C. or steam. When this tank is a pressurized tank, a liquid temperature exceeding 100 ° C. can be used. Although not required, the liquor may include at least some pulping agent such as sodium hydroxide (NaOH), sodium sulfide (Na ₂ S), polysulfide, anthraquinone, or equivalents or derivatives thereof, or a surfactant, Enzymes or chelating agents, or combinations thereof, can be included.

Preferably, the step-up / transfer device in steps (c) and (d) is a slurry pump (including a plurality), but many other step-up / transfer devices, such as a piston type solid pump and a high pressure eductor. Can also be used. Preferably, the slurry is transferred using one or more pressurizing / slurrying pumps. These are two or more slurry pumps, or slurry pumps, piston pumps,
Alternatively, a combination of eductors may be used. The transfer system can also include one or more reservoirs or surge tanks, as well as a transfer device. Preferably, at least one of the one or more transfer devices is provided with degassing capability to remove unwanted air or other gases from the slurry. Further, at the time of transfer, the chips may be subjected to some form of treatment, for example, degassing with a liquid, preferably a liquid containing the above-mentioned pulp-producing agent, or a treatment for infiltrating the same. The slurry is subjected to a pressure change or fluctuation at least once during the transfer, for example,
The pressure of the slurry can be changed from a first pressure to a second, higher pressure, and then selectively to a third pressure lower than the second pressure. As described in U.S. Pat. Nos. 4,057,461 and 4,743,338, changing the pressure of the slurry of chips and liquid improves the penetration of the liquid into the chips. This pressure pulsation can be achieved by changing the outlet pressure of a series set of transfer equipment or by controlling the slurry depressurization during pumping.

In another embodiment, it is not necessary to mix the cellulosic material with the liquid in the vessel, and the liquid can be first introduced into the cellulosic material by an eductor located at or outside the vessel. This liquid is preferably pressurized, so that a pressurized slurry of the cellulosic material and the liquid is formed.

The treatment tank in step (d) may be any of the steam treatment tanks described above, and is preferably a Diamondback (registered trademark) steam treatment tank. This tank may be a storage tank or surge tank that can store the cellulosic material prior to processing. Since the transfer step may require excess liquid that is not required for processing or storage, some type of dewatering device can be installed between the transfer device and the processing tank. One preferred dewatering device is a top separator sold by Ahlstrom Machinery. The top separator may be a standard type or a "reversed" type top separator.
This device may be of a stand-alone type independent of the outside, or may be directly attached to the processing tank. Further, an in-line liquid extracting device sold by Ahlstrom Machinery can be used as the dehydrating device. Preferably, the liquid extracted from the slurry by using a dehydrator is returned to the first tank or the transfer device, and can be used as a slurrying liquid. This liquor can be used wherever needed in a pulp mill. This liquid can be heated or cooled as needed. For example, this liquid is converted into a high-temperature liquid stream, for example,
The waste liquid having a temperature higher than 50 ° C. can be heated by flowing in an indirect heat exchange state. The liquid is typically pressurized using one or more conventional centrifugal liquid pumps.

In one preferred embodiment, step (d)
Is a steam processing tank for supplying one or more of the above-mentioned transfer devices. This device is preferably used with a feeder without a conventional high pressure feeder, but can also be used with a feeder with a high pressure feeder.

This method and apparatus for supplying chips from a distant location, for example, a wood yard, to a pulp manufacturing process not only provides for the chemical pulp manufacturing process, but also provides for the comminution of comminuted cellulosic fiber material from one location to another. It can be used in any pulp manufacturing process that conveys to a conveyor. The pulp manufacturing process to which the present invention can be applied, regardless of batch type or continuous type processing, all chemical pulp manufacturing processes, all mechanical pulp manufacturing processes,
Includes all chemical-mechanical pulping processes or thermo-mechanical pulping.

According to one of the other aspects, there is provided a method of supplying wood chips to the top of a treatment tank, the method comprising the following steps. (A) steaming the wood chips, degassing them and simultaneously heating them, (b) slurried the wood chips with a cooking liquor,
Producing a slurry of the liquid and the cellulosic material;
(C) boosting the slurry to a pressure of at least about 5 bar (gauge) at least 30 feet below the top of the treatment tank and transferring the pressurized wood chips to the top of the treatment tank; The pressure raising step is a step substantially performed on the slurry using one or more high-pressure slurry pumps. (D) When performing the transferring step of the step (c), a polysulfide, anthraquinone, or an equivalent thereof Alternatively, treating the wood chip with a derivative, surfactant, enzyme, chelating agent, or a combination thereof.

If the treatment vessel is upstream of a continuous or batch digester, step (c) is usually performed downstream of the treatment vessel. And (e) pressurizing the slurry at a location at least 30 feet below the top of the digester, prior to the continuous or batch digester and substantially immediately after steps (a) and (b). The step of raising the pressure may further include a step performed on the slurry using one or more high-pressure slurry pumps. A step of adjusting the temperature of the liquid while returning the liquid extracted from the digester to the processing tank and returning the liquid to the processing tank may be provided. The step of extracting the liquid from the processing tank is usually performed at the top of the processing tank.

[0028] The method may further include the step of returning the liquid from the downstream of the processing tank to the processing tank and adjusting the temperature of the liquid, wherein the step of adjusting the temperature of the liquid includes the step of transferring the liquid to the indirect heat exchanger. It can be done by passing through. The method also includes returning the liquid separated from the slurry at the top of the digester to one or more slurry pumps, increasing the pressure of the slurry, transferring the slurry to the digester, and circulating the temperature of the withdrawn liquid. An adjusting step may be further provided.

The apparatus and method described herein not only reduces the size and cost of the apparatus for transporting the comminuted cellulosic fibrous material, but also if the comminuted cellulosic fibrous material is processed during the transfer. The number and size of formal processing tanks can also be reduced. For example, this apparatus can eliminate the need for a conventional pretreatment or infiltration tank located in front of the digester. This device also has the potential to improve the overall energy economy of the pulp mill.
This and other aspects of the invention will become apparent upon reading the detailed description and upon review of the following drawings.

According to one of the other aspects, at least a first and a second pump are connected in series, and at least a first and a second station equipped with a solid / liquid separator are connected in series, and the comminuted cellulose is used. A method for treating a fibrous material is provided.
The method comprises the steps of (a) pumping a slurry of the finely divided cellulose fiber material using a pump connected in series, and (b) separating a liquid from the slurry at each station to substantially convert a circulating liquid and a main stream. (C) sodium hydroxide, sodium sulfate; polysulfide, anthraquinone, or an equivalent or derivative thereof; a surfactant; An agent comprising at least some agent selected from the group consisting substantially of: an enzyme or a chelating agent; or a combination thereof, to the slurry upstream of each pump, such that the cellulosic material is transferred from each pump to each station. A pretreatment of the cellulosic material is performed when transferring.

[0031] A step of degassing the slurry at at least one station may be further provided. At least first, second and third pumps and stations connected in series can be used, and (d) circulating the liquid drawn from the third station to a point upstream of the second pump; (E) circulating the liquid drawn from the second station to a location upstream of the first pump (step (d) can be performed downstream of the first station). Step (d)
During at least one of (e) and (e), a step of passing the withdrawn liquid through a heat exchanger and changing the temperature thereof may be further provided. For example, the temperature of the withdrawn liquid can be raised or lowered by about 1 to about 10 ° C., depending on the amount of this liquid and the amount of heat that can be used for heating or cooling.

Step (c) can be performed by adding a different drug or mixture of drugs upstream of each pump, so that a significantly different treatment of the slurry of cellulosic material in transferring the slurry from each pump to the associated station. Done. Step (a) is performed by raising the slurry to a pressure of at least 5 bar. Also, a step may be provided to draw liquid from at least one station using an eductor (also known as an ejector) instead of a flash tank and / or a control valve.

According to another aspect of the invention, one of the treatments that can be used in transferring the comminuted cellulosic fibrous material is the removal of metal ions. It is recognized in the art that the presence of certain metal compounds and ions, such as calcium ions, magnesium ions, etc., can interfere with the pulp manufacturing process or bleaching reaction or cause undesirable " Or “scaling”. It is also known that the metal content of a cellulosic material can be easily determined by exposing the cellulosic material to an acidic solution that can dissolve the metal compound or ions, or by binding with certain metals, for example, by washing. This can be reduced by exposing the cellulosic material from acidic to slightly alkaline in the presence of a chelating agent (also known as a sequestering agent) that facilitates separation and removal. In accordance with the present invention, these harmful metal-containing compounds and ions can be removed from the cellulosic material prior to the cooking or bleaching process, so that these metals can perform these processes without interfering with these processes. Nor does the equipment used to generate scale.

According to this aspect of the invention, at least a first and a second serially connected pump and at least a first and a second serially connected station each comprising a solid / liquid separator. There is provided a method of treating a comminuted cellulosic fibrous material with a material to reduce the metal content of the cellulosic material. This method includes the steps of (a) pumping a slurry of the finely divided cellulose fiber material using a pump connected in series, and (b) separating a liquid from the slurry to some extent at each station to separate a circulating liquid and a main stream. Substantially independent and recirculating liquid separated from at least one station upstream of one of the pumps;
Adding at least one agent selected from the group consisting essentially of a chelating agent or a combination thereof, and adding an agent that dissolves or sequesters the metal-containing compound to the slurry at or upstream of at least one pump; And at least some of the harmful metals present in the cellulosic material (eg, at least about 10%, preferably about 2%).
0% to 80%) from the cellulosic material prior to the treatment.

(D) In carrying out step (a) or step (b), at least some of the liquid is withdrawn from the slurry and at least some (for example, at least about 10%, preferably about 20%) (80%). The liquid can be withdrawn in a liquid separator, for example a conventional top separator or an in-line liquid withdrawal device, or the liquid can be withdrawn simply via a branch line of a circulation line. Also, step (d) can be performed substantially simultaneously with step (b) and using substantially the same equipment as step (b). Further, a step of (e) introducing the liquid into the circulating liquid to substantially replace the liquid removed in step (d) may be further provided. Step (e), which is a liquid introduction procedure, can be performed substantially directly below where step (d) is performed or elsewhere in the system. Also, step (e) can be performed substantially in conjunction with step (c), and the replacement fluid can be introduced substantially with the treatment agent.

The present invention preferably further comprises, before that, a step of (f) treating the cellulose material with an alkali solution and (g) digesting the cellulose material by an alkaline digestion process. Steps (a) to (e) are preferably performed substantially immediately before steps (f) and (g). The alkaline liquor may be, for example, a kraft white liquor, a green liquor or a black liquor, which may include a yield or strength enhancing additive as described above. Thus, in a preferred embodiment of the invention, the medicament used to carry out step (c) is introduced at or upstream of the first pump,
The drug used to perform step (f) is introduced at or upstream of the second pump.

According to another aspect, there is provided a method of treating a comminuted cellulosic fiber material. This method
(A) pumping the slurry of the comminuted cellulosic fibrous material using at least a first and second series-connected pump; and (b) separating the liquid from the slurry to some extent at each station to form Substantially independent of the main stream and recirculating the liquid separated from the at least one station upstream of one of the pumps; and (c) adding a treatment agent to the slurry upstream of the at least one pump; As a result, pretreatment of the cellulosic material takes place while transferring the cellulosic material from said pump to its associated station, and (d) transferring the liquid removed from the second station to a point upstream of the first pump. Circulating. If at least the first, second and third pumps and stations are provided, the method further comprises the step of (e) circulating the liquid removed from the third station to a point upstream of the second pump. Details of these steps and the added steps are as described above.

According to one aspect of the present invention, there is provided an apparatus for producing chemical cellulose from comminuted cellulosic fibrous material. This device comprises the following components: That is,
Steam treatment tank for steaming and degassing the comminuted cellulose fiber material; a vertical treatment tank having a pressure higher than atmospheric pressure, having an inlet for slurry of the comminuted cellulose fiber material at the top and an outlet at the bottom; A pressurizing and transferring means for pressurizing the slurry of the cellulose material from the tank and transferring the same to the treatment tank inlet, comprising an inlet and an outlet,
One or more high-pressure slurry pumps provided below the top of the processing tank; a means for increasing and transferring pressure; a means for circulating a liquid from an outlet of at least one high-pressure slurry pump to an inlet thereof. .

The circulating means may be a conduit or a connection associated with another component. However, any conventional structure that allows or provides this circulation, for example (in a conduit or independent of a conduit)
Valves, tanks, ejectors, pumps, ducts, heat exchangers and the like can be used.

The apparatus preferably further comprises a liquid return line from the top of the processing tank. This return line is connected to one inlet or outlet of the slurry pump during operation. The device can include a heat exchanger located in the return line. This heat exchanger is preferably a liquid / liquid indirect heat exchanger. This heat exchanger can be used to cool or heat the liquid in the return line,
It is preferable to cool the liquid in the return line by connecting it to a supply of cold liquid to a temperature below the temperature at which the liquid flashes in the device.

[0041] The apparatus may further include an inlet connected to the steam processing tank and operated, and an outlet connected to the inlet of one or more slurry pumps and operated. The apparatus may further include a liquid return line from the top of the processing tank. This return line is connected to the slurry tank and the heat exchanger in the return line during operation.

Preferably, said at least one pump is at least two pumps, each pump having recirculation means as described above. The recirculation means may comprise a first valve in the recirculation conduit and a second valve between the pump outlet and the treatment tank, each pump comprising a recirculation means as described above in this connection. preferable.

The processing tank may include a first processing tank, and the apparatus of the present invention may include a second processing tank. The main conduit is connected to the outlet of a pump (ie, the last pump in a group of pumps arranged in series), and a flow branch with an inlet and at least two outlets is provided. The main conduit is connected to the inlet of the flow branch, one of the outlets of the flow branch is connected to the first processing tank and the other outlet is connected to the second processing tank. The first processing vessel may have two or more inlets, and the two or more outlets of the flow splitter may be connected to the two or more inlets of the first processing vessel. The flow divider may include a chamber containing a substantially triangular static baffle plate structure, the triangular point being substantially aligned with the inlet.

In accordance with another aspect of the present invention, there is provided a method of supplying a cellulosic material to the top of a processing vessel, the method comprising the following steps: (a) steaming the cellulosic material; Degassing and simultaneously heating the cellulosic material; (b) slurrying the cellulosic material with a cooking liquor to produce a slurry of liquid and cellulosic material; and (c) at least 30 feet below the top of the treatment vessel. Pressurizing the slurry at a location and transferring the pressurized cellulosic material to the top of the treatment tank, comprising the step of applying pressure to the slurry using two or more high-pressure slurry pumps .

The method also includes (d) establishing a recirculation loop between each pump outlet and inlet during startup. For example, the first valve in the recirculation loop,
A second valve can be provided between each pump outlet and the treatment tank, wherein step (d) opens the first valve during start-up and the second valve is at least partially (eg,
(Completely) closed, and then the method may further comprise the step of (e) closing the first valve and opening the second valve after startup. In this method, one of the pump inlets (preferably,
Return the liquid to the first of the series connected pumps)
The method can include the step of partially cooling the coolant (eg, with an indirect liquid / liquid heat exchanger) so that the return liquid has a temperature below the flash temperature during handling.

The method of the present invention can further be carried out using at least a second processing tank or a first processing tank having two or more inlets, and statically divides the slurry flow from the last outlet of the pump. And directing each portion of the stream to each of the two or more inlets of the processing vessel or the first processing vessel.

In accordance with another aspect of the present invention, there is provided a method of supplying a comminuted cellulosic fibrous material to the top of a treatment vessel, the method comprising the following steps. That is, (a)
Steaming and degassing the cellulose material and simultaneously heating the cellulose material; (b) slurrying the cellulose material with a cooking liquor to produce a slurry of the liquid and the cellulose material; Pressurizing the slurry at a location at least 30 feet below the top and transferring the pressurized cellulosic material to the top of the treatment vessel, wherein the pressurizing step comprises using one or more high pressure slurry pumps And (d) establishing a recirculation loop between the pump outlet and the inlet during start-up. A first valve can be provided in the recirculation loop and a second valve can be provided between the pump outlet and the treatment tank; step (d) opens the first valve on startup and the second valve is at least partially Can be done to close;
The method may further include (e) closing the first valve and opening the second valve after startup. Cooling and returning the liquid and branching the flow can also be performed as described above.

In accordance with another aspect of the present invention, there is provided a static flow branch, the branch comprising a static chamber, an inlet connected to the chamber, and at least two outlets. A triangular static baffle plate structure is contained within the chamber, and the triangular point is disposed substantially aligned with the entrance.

It is a primary object of the present invention to provide a simple and effective apparatus and method for supplying a slurry of a cellulosic material to a treatment tank while improving operability and maintainability. This and other objects of the present invention will become more apparent upon a review of the detailed description of the invention and the appended claims.

[0050]

DETAILED DESCRIPTION OF THE INVENTION The apparatus described and illustrated in FIGS. 1-3 is a continuous digester system, but the method and apparatus of the present invention may comprise one or more batch digesters or a continuous digester. It is understood that it can also be used to feed an infiltration tank connected to a digester. As shown, the continuous digester that can be used in the present invention is preferably a Kamiya type (registered trademark) continuous digester, and may be a kraft (ie, sulfate) pulp method, a sulfite pulp method, a soda pulp method, or any of these. Can be used in a method equivalent to the above. Specific digestion methods and equipment that can be used in the present invention include, for example, the MCC®, EMCC®, Low Solid® processes and digesters sold by Ahlstrom Machinery. is there. Additives for maintaining strength or yield, such as anthraquinone, polysulfide, or equivalents or derivatives thereof, can also be used in the digestion process employing the present invention.

FIG. 1 shows one typical prior art apparatus 10 for feeding a slurry of a comminuted cellulosic fiber material, for example hardwood chips, to the top of a continuous digester 11.
The digester 11 usually extracts excess liquid from the slurry,
At the inlet 13 of the digester a bleed screen 12 used to return it to the feeder 10 is provided. The digester 11 also includes at least one bleed screen 14 that is used to withdraw waste cooking liquor during or after the pulp manufacturing process. The digester 11 also typically has a cooking liquor circulation, for example, an MCC®, EMCC® digester cooking circulation or a Low Solid® digester circulation having a bleed conduit and a diluent addition conduit. And one or more liquid drainage screens (not shown) that can be connected to the device. Cooking liquor, such as kraft white liquor, black liquor or green liquor, can be added to these circulation lines. The digester 11 also comprises an outlet 15 for discharging the manufactured chemical pulp. The produced chemical pulp can be sent for further processing, for example, washing or bleaching.

In the prior art supply device 10 shown in FIG. 1, the comminuted cellulosic fiber material 20 is introduced into a chip bin 21. Typically, the cellulosic material 20 is softwood or hardwood chips, but any form of comminuted cellulosic fibrous material, such as sawdust, grass, straw, bagasse, kenaf or other agricultural waste, or mixtures thereof, etc. Can be used. Although the term “chip” is used in the following discussion when referring to the comminuted cellulose fiber material, this term is not limited to wood chips,
It should be understood that any of the above-mentioned comminuted cellulosic fiber materials may be referred to.

The tip bin 21 can be a conventional bottle with a vibrating outlet or US Pat. No. 5,500,083.
A DIAMONDBACK (registered trademark) steam treatment tank, which is described in Japanese Unexamined Patent Application Publication No. 2000-216 and sold by Ahlstrom Machinery, has no vibratory discharge port, and has a one-dimensional reduction section and an outlet with side relief. it can. This bin 21 can typically be provided at the inlet with an airlock device, means for monitoring and controlling the level of chips in the bin, and a suitable mechanism for controlling the pressure in the bin. Regardless of whether the steam is fresh steam or steam generated from the evaporation of the waste liquid (i.e., flash steam), it is usually added to the bottle 21 via one or more conduits 22.

The bottle 21 is usually discharged to a weighing device 23, for example, a chip meter sold by Ahlstrom Machinery. However, other forms of metering device, for example, screw metering devices, can also be used. The metering device 23 discharges to a pressure shut-off device 24, for example, a low pressure feeder sold by Ahlstrom Machinery. The pressure shut-off device 24 shuts off the pressurized horizontal processing tank 25 from the substantially atmospheric pressure existing thereon.

Tank 25 is used to treat the cellulosic material with pressurized steam, for example, steam at about 10 to 20 psig. The tank 25 can be provided with a screw conveyor like a steam processing tank sold by Ahlstrom Machinery. Clean steam or flash steam is applied to one or more conduits 28.
Is added to the tank 25 via the

After treatment in tank 25, the cellulosic material is:
It is transferred to a high-pressure transfer device 27, for example, a high-pressure feeder sold by Ahlstrom Machinery. Typically, the steamed cellulosic material is transferred to a feeder 27 using a conduit or chute 26, for example, a chip chute sold by Ahlstrom Machinery. A heated cooking liquor, for example, a mixture of kraft black liquor waste liquor and white liquor, is typically added to chute 26 via conduit 29 to produce a slurry of cellulosic material and liquid in chute 26.

In the prior art apparatus of FIG. 1, a diamond back (DIAMON) disclosed in US Pat.
When a DBACK® (registered trademark) steam processing tank is employed, the high-pressure processing tank 25 and the pressure shut-off device 24 can be omitted.

The conventional high-pressure feeder 27 includes a chute 2
6, a low-pressure outlet connected to the conduit 30, a high-pressure inlet connected to the conduit 33, and a high-pressure outlet connected to the conduit 34, driven by a variable speed electric motor and a speed reducer (not shown). Equipped with a pocketed rotor. The low pressure inlet receives the heated chip slurry from the chute 26 into the rotor pocket. 30 of feeder 27
The screen at the outlet at the point holds the chips in the rotor, but the liquid in the slurry passes through the rotor and
And the liquid is withdrawn via the pump 31. As the rotor turns, the chips held in the rotor are placed in conduit 3
It is exposed to the high-pressure liquid sent from the pump 32 via 3. The high-pressure liquid slurries chips sent from the feeder, and the slurry flows to the top of the digester 11 via the conduit 34. Upon reaching the inlet of the digester 11, some excess liquid used to slurry the chips in the conduit 34 is withdrawn from the slurry via the screen 12. Excess liquid withdrawn via screen 12 is returned to the inlet of pump 32 via conduit 35. The liquor in conduit 35, to which fresh cooking liquor may be added, is pumped up by pump 32 and passed through conduit 33 and used to slurry chips from feeder 27. The chips held by the screen 12 pass downward through the digester 11 for further processing.

The liquid taken out of the feeder 27 via the conduit 30 and the pump 31 is supplied to the conduit 36, the sand separator 37, the conduit 38, the in-line liquid extracting device 3
9. Recirculated via conduit 29 to chute 26 above feeder 27. The sand separator 37 is a cyclone type separator for removing sand and debris from the liquid. The in-line liquid withdrawing device 39 is a static screen device for removing excess liquid from the conduit 38, sending it out via the conduit 39 ', and storing it in the level tank 40.
The liquid stored in the tank 40 is supplied to a conduit 41 and a pump 42.
(I.e., a replenisher pump) and via conduit 43 back to the top of the digester. Fresh cooking liquor is also in conduit 41 or 4
3 can be added.

FIG. 2 shows another prior art apparatus 110 for supplying chips to a digester. This device is disclosed in U.S. Patent Nos. 5,476,572, 5,622,598.
No. 5,635,025 and the process and equipment described therein. The equipment and processes used are:
It is marketed collectively by Ahlstrom Machinery, Inc. under the trademark LO-LEVEL®. 2 that are identical to those found in FIG. 1 are identified by the same reference numerals. Components that perform a similar or similar function to those found in FIG. 1 have reference numbers with the number "1" prefixed to the reference numbers found in FIG.

As in the apparatus of FIG. 1, the chips 20 are introduced into a steam treatment tank 121 where they are exposed to steam introduced via a conduit 22. The tank 121 is a measuring device 1
Discharge to 23 and then to conduit 126. Conduit 126 is preferably a tip tube sold by Ahlstrom Machinery. The cooking liquor is usually supplied to the conduit 29 of FIG.
Is introduced into the tube 126 via a conduit 55 similar to
Vessel 121 is a diamond back (registered trademark) described in US Pat. No. 5,000,083.
Since it is preferably a steam processing tank, the pressure shut-off device 24 of FIG. 1 and the high-pressure steam processing tank 25 of FIG. 1 are unnecessary in this prior art apparatus. US Patent No. 5,476,5
Instead of directly discharging the slurry of chips and liquid to the feeder 27 as disclosed in Japanese Patent Publication No. 72-72, a high-pressure slurry pump 51 supplied by a conduit 50 is used to transfer chips to the feeder 27 via a conduit 52. Used. Pump 51 may be a Hydrostar pump manufactured by Wemco or Lawrence.
Preferably a similar pump of manufacture. Pump 51
Chips sent via the feeder 27 are transferred to the digester 11 by a feeder 27, which is similar to that shown and described with reference to FIG.

In addition to using the pump 51 to send the slurry to the feeder 27, the apparatus of FIG. 2 does not require the pump 31 of FIG. The pump 51 is connected to the feeder 27
A driving force for sending the liquid to the liquid level tank 53 via the via, the conduit 30, the sand separator 37, the in-line liquid extracting device 39, and the conduit 129 is applied.

The function of the level tank 53 is as follows:
No. 08 / 428,302, filed on May 25. The presence of the tank 53 ensures that the liquid is sufficiently supplied to the inlet of the pump 51 via the conduit 54. This tank can also supply liquid to tube 126 via conduit 55. The presence of the liquid tank 53 also allows the operator to change the liquid level in the supply system so that the liquid level can be raised to the metering device 123 or even to the bin 121 if desired. This option is available on December 5, 1994.
It is also described in the specification of US patent application Ser.

FIG. 3 shows one preferred embodiment 210 of the supply apparatus which further simplifies the prior art supply apparatus shown in FIGS. In the preferred embodiment shown in FIG.
The high-pressure feeder, component 27 of FIGS. 1 and 2, has been eliminated. Instead of sending the chips to the feeder 27 by gravity in the chute 26 in FIG. 1 and by the pump 51 in FIG. 2, at least one, preferably two high pressure slurry pumps 2 are used.
The slurry is transferred to the inlet of the digester 11 using 51, 251 '. The components of FIG. 3 that are substantially identical to those seen in FIGS. 1 and 2 are identified with the same reference numerals.
Components that perform a function similar or similar to those found in FIGS. 1 and 2 have reference numbers with the number "2" prefixed to the reference numbers found in FIGS. 1 and 2.

According to the embodiment shown in FIG. 3, the chips 20 are introduced into the steam processing tank 221 in the same manner as in the procedure shown in FIGS. The chips are preferably introduced using a sealed horizontal conveyor as disclosed in US patent application Ser. No. 08 / 713,431, filed Sep. 13, 1996. In addition, the steam treatment tank 221 is a U.S. Pat.
No. 083, the diamond back (DIAMONDBAC
K) (registered trademark) preferably a steam treatment tank,
Steam is added to the tank via one or more conduits 22. The steam processing tank 221 usually includes a conventional level monitoring / control device as well as a pressure relief device (not shown). The tank 221 discharges the steam-processed chips to the measuring device 223. Metering device 223 may be a pocketed rotor-type device, such as a tip meter or screw-type device, as described above.

In one embodiment, metering device 223 discharges directly to conduit or chute 226. However, in an optional embodiment, a pressure shut-off device, such as a pocketed rotor shut-off device indicated by dashed line 224, for example, a conventional low pressure feeder, can be installed between metering device 223 and chute 226. Without the pressure cut-off device 224, the pressure in the chute 226 is substantially atmospheric, but with the pressure cut-off device 224, the chute 226 is
The medium pressure will be in the range of 1 to 50 psig, but is preferably 5 to 25 psig, most preferably about 10 to 20 psg.
ig. The cooking liquor is supplied to the chute 2 as described above.
26 (see line 226 'in FIG. 3) so that a slurry of chips and liquid is produced in a chute 226 having a detectable liquid level (not shown).
The chute 226 stands. The slurry in the chute 226 is discharged to the inlet of the pump 251 via the curved pipe outlet 250. When the slurry is introduced at the inlet of the pump 251, a liquid stream is usually added from the liquid tank 253 via a conduit 254, which is described in US patent application Ser.
No. 8,302.

The pump 251 may be a centrifugal high pressure, swirl screw, slurry pump, such as a Hidrostal manufactured by Wemco of Salt Lake City, Utah.
(Registered Trademark) pump is preferred. Pump 25
1 may alternatively be a slurry pump manufactured by Lawrence of Lawrence, Mass. The pressure at the inlet to the pump 251 depends on whether or not a pressure shut-off device 224 is used.
It varies within the sig range.

In the preferred embodiment shown in FIG. 3, the outlet of pump 251 discharges to the inlet of pump 251 '. Pump 251 'is the same type of pump as pump 251, but preferably has the same or higher pressure specifications. When using two pumps, the pressure generated at the outlet of pump 251 'is typically 150-400 psig (i.e., 34
5 to 920 feet (gauge)), but about 200 to
300 psig (ie, 460-690 feet of water column) is preferred. If necessary, the slurry liquid in conduit 252 is supplied to tank 25 via conduit 56 and liquid pump 57.
Liquid can also be added from step 3.

Although the embodiment shown in FIG. 3 includes two pumps, only one pump, or three or more pumps, can be used in series or in parallel. In these cases, the discharge pressure from one pump or from the last pump is preferably the same as the discharge pressure from the upper pump 251 '.

The pressurized, usually heated slurry is discharged from pump 251 ′ to conduit 234. Conduit 23
4 sends the slurry to the inlet of the continuous digester 11. Excess liquid in the slurry is separated from the slurry at the screen 12, which is conventional. Excess liquid is passed through conduit 235
Returned to the supply device 210 via It is preferably returned to the liquid tank 253 and used for slurrying in the conduit 250 via the conduit 254. The liquid in conduit 235 can be passed through sand separator 237 if desired. The sand separator 237 can be designed for pressure or non-pressure, depending on the desired mode of operation.

The high pressure feeder (2 in FIGS. 1 and 2) uses the pressure of the liquid returned via the conduit 35 as an essential part of the method for slurrying the flow from the high pressure feeder to the digester 11.
Unlike the prior art apparatus employing (7), returning the high-pressure recirculating liquid 235 to the inlets of the pumps 251 and 251 'is not essential in the present invention. The energy available at the pressure of the stream in line 235 can be used wherever needed in the pulp mill. However, in a preferred embodiment, the present invention provides that the available pressure in conduit 235
1 and 251 'are used to minimize the energy requirements.

The pressure in the return line 235, typically about 15
How to use 0-400 psig depends on the feeder 2
It depends on ten operating modes. If the tank 226 is operated at no pressure, ie, in a substantially atmospheric pressure mode, the conduit 23
The high pressure liquid returned in 5 must be returned to substantially atmospheric pressure before being introduced into conduit 250. One means of doing this is to use a pressure control valve 58 and a pressure indicator 59 in conduit 235. The opening degree of the valve 58 is controlled so that a predetermined pressure reduction degree is obtained in a line 235 downstream of the valve 58. Further, the design of the liquid tank 253 allows it to act as a "flash tank", such that the hot pressurized liquid in the conduit 235 evaporates rapidly to provide a steam source in the tank 253. This steam may be used in other locations, but in particular in the tank 221 via the conduit 60. However, in a preferred embodiment, the hot pressurized liquid in conduit 235 is used to add to the discharge of pump 251 ', for example, via conduit 61 and pump 62. The pressure in conduit 235 is pumped 251 and 251 ′ via conduit 63 with or without pump 64 (instead of or in addition to pumps 62 and 64, respectively, and possibly using a check valve).
Can also be used to add to the flow of conduit 252 between. By recycling some of the pressure available to line 235, the energy requirements of pumps 251 and 251 'can be reduced to some extent. Also, the heat of the liquid in line 235 can be used in heat exchange with one or more liquid streams in the pulp mill that require heating.

The pumping and transfer functions of the pumps 251 and 251 ′ may instead be replaced by conventional eductors, for example, Fox Valve Develop.
mentCorporation). Alternatively, pumps 251 and 251 'can be used with an eductor to increase the pressure at the pump inlet or outlet. The eductor can also be used as a means for introducing a liquid into the chip. For example, an eductor can be provided at or below the outlet of the tank 226, and the eductor can be used to initially introduce liquid to the chip. The eductor includes one or more conduits 250, 252,
A venturi-type throttle provided at 234 may be used, into which a high-pressure flow of liquid is introduced. This high pressure fluid can be obtained from any available source, but upstream of valve 58, conduit 2
Preferably it is obtained from 35. An example of an eductor is 7 in Figure 3.
It is shown schematically at zero.

The pumps 251 and 251 ′ do not necessarily have to be of a centrifugal type, and the digester 11
Any type of slurry transfer device that can directly act to pressurize and transfer the slurry of chips and liquid to the inlet of the slurry may be used. For example, solid transport pumps commonly used in the mining industry can be used, such as a two-shaft piston solid pump, such as the KOS solid pump sold by Putzmeister, or other similar conventional pumping equipment. .

One of the functions of the conventional high pressure feeder 27 of FIGS. 1 and 2 is that if any of the components of the other supply system fails or fails, the device and transfer conduit, For example, to act as a shut-off valve to prevent the pressure drop in conduits 34 and 35 of FIG.
In the supply device 210 of the present invention, another means is provided to prevent such depressurization due to a malfunction or failure. For example, shown in FIG. 3 is a one-way (check) valve 65 in conduit 234 that prevents high pressure flow from flowing back to pump 251 or 251 '. In addition, conventional automatic (eg, solenoid operated) shut-off valves 66 and 67 are provided in conduits 234 and 235, respectively, and high pressure conduit 23
4,235 is cut off from the remaining supply device 210. In one preferred mode of operation, a conventional pressure switch 68 is provided in conduit 234, downstream of pump 251 '. A switch 68 is used to monitor the pressure in line 234, and if the pressure deviates from a predetermined value, a conventional controller 69 automatically closes valves 66 and 67 to feed digester 11 to the feeder. Cut off from 210. These valves may also close automatically when a flow direction sensor detects a reversal of flow in conduit 234.

Although the above depressurization preventing means 65 to 69 are preferable, those in which valves, sensors, indicators, alarms and the like are arranged in other forms also have a function of remarkably preventing decompression of the digester 11. Can be a means for preventing depressurization as long as

Although the apparatus 210 is preferably used with the continuous digester 11, other apparatus having an inlet at the top,
It can also be used with vertical processing tanks at pressures above atmospheric pressure (typically at least about 10 bar (gauge)).

FIG. 4 shows yet another embodiment in which the concept of chip transfer is extended from a digester feeder to a wood yard in a pulp mill. FIG. 4 shows an apparatus 510 for supplying a comminuted cellulosic fiber material to a pulp manufacturing process. It consists of a subsystem 410 for introducing chips from the wood yard to the apparatus 510 and a subsystem 310 for processing and supplying chips to the digester 11. Subsystem 31
0 is substantially the same as the device 210 shown in FIG.

Again, the components of FIG. 4 that are identical to those found in FIGS. 1-3 are identified by the same reference numerals. Components that perform similar or similar functions to those found in FIGS. 1-3 have reference numbers with the number "3" prefixed to the reference numbers found in FIG.

As described above, wood is supplied to the wood yard of the conventional pulp mill in various forms. Typically, wood or other comminuted cellulosic fiber material is broken into chip-like forms and stored in an outdoor chip storage or chip storage silo. In FIG. 4, the chip is supplied to the chip storage area 80.
As shown. In a preferred embodiment of the invention, chips from chip storage 80 or other reservoirs or the like are transported by conventional means, for example, by a conveyor or a front-end loader (not shown) and introduced 20 into tank 81. This tank may be a Diamondback (R) tank or other conventional storage tank. The tank 81 is at a pressure higher than the atmospheric pressure, for example,
It can be operated at 0.1 to 5 bar. If the vessel is operated at a pressure higher than atmospheric pressure, some form of pressure shut-off device (not shown) may be provided at the inlet of the vessel to prevent depressurization. This device may be a star-type shut-off device such as a low pressure feeder or airlock feeder sold by Ahlstrom Machinery, or a screw capable of sealing as described in co-pending US patent application Ser. No. 08 / 713,431. A type feeder may be used.

Liquids such as fresh water, steam condensate,
A liquid containing the cooking liquor is introduced into the tank 81 via one or more conduits 82, and a slurry of the liquid and chips is generated, and a detectable liquid surface is set up in the tank 81. Means for monitoring and controlling the liquid level of the tank 81 and the level of the chips can also be provided. This liquid is a high temperature liquid, for example, a temperature of 50 to 10
High temperature water of 0 ° C. or steam condensed water may be used. When this tank is a pressure-resistant tank, a liquid having a temperature exceeding 100 ° C. can be used. Preferably, but not necessarily, the liquor contains at least some active pulping agent, for example,
Sodium hydroxide (NaOH), sodium sulfide (Na
₂ S), can polysulfide, anthraquinone, or equivalent or derivatives with these or surfactants, enzymes or chelating agents, or also be included a combination thereof.

From the tank 81, the slurry is discharged to an inlet of a slurry pump 85 via a conduit 84. The discharge from the tank 81 may be performed with the aid of a discharge device 83 (which may not be necessary if a Diamondback® discharge is used). The slurry 8 in conduit 84 also has
Liquid may be added via 2 'to assist. If the conduit 82 'is the only liquid introduction means, the liquid level can be in the conduit 84 and not in the tank 81. Pump 85 may be any type of slurry pump described above, for example, a Wemco or Lawrence pump or equivalent, or other type of solid or slurry transfer device. Although only one pump 85 is shown, multiple pumps or similar devices may be used to transfer the slurry to vessel 321 via conduit 86. Slurry transfer via conduit 86 may include one or more reservoirs or surge tanks (not shown). Preferably, one or more pumps 85 are provided with at least one degassable device to remove unwanted air or other gases from the slurry.

The slurry discharged from the pump 85 is transferred to the subsystem 810 via the conduit 86. Subsystem 810 depends on the pulp mill layout,
Near subsystem 710, ie, subsystem 7
It may be located within about 30 feet of 10, or at a location that is substantially remote from subsystem 710, such as more than 1/2 mile. Therefore, conduit 8
6 is indicated by a broken line to indicate the above assumed distance between the subsystems 710 and 810.

The pressure in conduit 86 depends on the number of pumps or other transfer devices used, and on the height and distance at which the slurry must be transferred. The pressure in conduit 86 is about 5 p
It varies from sig to over 500 psig.

During the transfer, the chips may be subjected to some type of treatment, for example, a degassing treatment, or a permeation treatment with a liquid, preferably a liquid containing a pulp-making agent as described above. The slurry can also be subjected to a pressure change at least once during transfer. For example, the slurry pressure may be changed from a first pressure to a higher second pressure and then to a third pressure lower than the second pressure. U.S. Pat. Nos. 4,057,461 and 4,74
As described in Japanese Patent No. 3,338, if the pressure of the slurry of chips and liquid is changed, the permeation between chips and liquid is improved. This pressure pulsation change is achieved by changing the outlet pressure of a set of transfer devices arranged in series or by controlling the depressurization of the slurry during pumping.

[0086] The slurry in the conduit 86 is introduced into the inlet of the tank 321. The illustrated tank is a processing tank, that is, a steam processing tank, but may be a storage tank, a permeation tank, or a digester. Since transfer via conduit 86 typically requires excess liquid that is not required for processing or storage, some type of dewatering device 87 can be installed between the transfer device and the processing tank. One preferred dewatering device is a top separator sold by Ahlstrom Machinery. The top separator may be a standard type or a "reversed" type top separator. This device may be of a stand-alone type independent of the outside, or may be directly attached to a processing tank as shown in the figure. Preferably, the liquid extracted from the slurry using the dewatering device 87 is supplied to the tank 82 or the conduit 8.
It can be returned to the inlet of the pump (s) 85 via 8 to help slurry the chips. Device 87
This liquor can be used wherever needed in a pulp mill. This liquid in conduit 88 may be heated or cooled as needed in heat exchanger 90, and may include one or more conventional centrifugal liquid pumps 8
9 to increase the pressure. The liquid in conduit 88 can be introduced into vessel 81 via conduit 82 and into conduit 84 via conduit 82 '.

The processing tank 321 shown is the tank 2 shown in FIG.
A steam treatment tank similar to 21, for example, a Diamondback (registered trademark) steam treatment tank. The supply device 310 is similar to the device 210 shown in FIG. For example, it is supplied from the chip supply device 410 to the digester supply device 310 and further supplied to the digester 11. Apparatus 3 of FIG.
10 simply removes the chips from chip storage 80 to digester 11
Note that this is one of the subsystems of the overall system that supplies the system. The entire system may include one or more subsystems 310 that feed the digester 11.

FIG. 5 shows a further embodiment 610 which is an extension of the device 510 shown in FIG. This device 610 is a combination of three subsystems 710, 810, 910. The subsystem 710 is similar to the device 410 of FIG. 5 that are substantially the same as those found in FIGS. 1-4 are identified by the same reference numerals.

The wood chips 20 or other comminuted cellulosic fiber materials are introduced from a chip storage 80 into a tank 81 with or without pressure shut-off. The treatment of the chips in the vessel 81 is performed with a gas such as steam or hydrogen sulfide introduced in one or more conduits 82, or with water or a cooking agent-containing liquid. Vessel 81 may be any type of vessel, but is preferably a Diamondback® bottle as described above. The processed chips are stored in tank 8
1 to a conduit 84. Although any type of discharge mechanism can be used, the discharge of chips from the vessel 81 is performed without the aid of mechanical agitation or vibration, as is characteristic of a Diamondback® chip bin. Is preferred. The conduit 84 may be any type of pipe or chute, but is preferably a curved tip tube as described above.

The conduit 84 introduces the chips to the inlet of the slurry pump 85. The slurry pump 85 may be of the type manufactured by Wemco or Lawrence as described above. Typically, the liquid used to slurry is first introduced to the chips in conduit 84, for example, using conduit 82 ', and the vessel 8
1 or raise the liquid level to the conduit 84. The liquid introduced via conduit 82 'may be a liquid containing a processing agent, such as water or Kraft liquid, with or without strength or yield enhancing additives. Supplemental fluids, for example, fluids containing these drugs, are usually
Added from conduit 782.

The slurry in the conduit 86 is supplied to a liquid separating device 88.
7 to the subsystem 810. This device is similar in operation to the device 87 shown in FIG. The liquor removed via separator 887 can be returned to subsystem 710 via conduit 88 or used elsewhere in the pulp mill via conduit 888. When returning fluid to subsystem 710 via conduit 88, additional fluid or drug is added to this fluid via conduit 788, which is heated in indirect heat exchanger 90 via conduit 790 and pressurized by pump 89. This liquid can then be reintroduced to vessel 81 via conduit 82 or to conduit 84 via conduit 82 '. Subsystem 710 may also include a liquid storage tank similar to tank 353 shown in FIG. Thus, by using the heater 90 and the drug addition 782 or 788, the slurry of cellulosic material that is transferred from the subsystem 710 to the subsystem 810 via the conduit 86 can be treated with the drug to any desired temperature. Can be heated. For example, the slurry in conduit 86 may be heated to about 90 ° C. in the presence of alkali or sulfide.
Upon heating, some pretreatment of the cellulosic material occurs during the time that the slurry resides in conduit 86 before being introduced into subsystem 810. Of course, other agents may be used in conduit 86 at lower temperatures.

The chips taken into the separator 887 are stored in the tank 8
21. The tank 821 may be a tank similar to the tank 81, but is preferably a high cylindrical tank having a liquid level of 823, for example, 20 to 50 feet high. The gas space 824 may be maintained above the liquid level 823. Tank 821
Can be maintained at atmospheric pressure or at a pressure above atmospheric pressure, depending on the processing performed in vessel 821, for example, at 0.2 to 10 bar (gauge) (eg, about 5 bar).
The temperature of vessel 821 ranges from 50 to 300 ° C, but is typically between about 50 to 150 ° C. The liquid can be introduced into the tank 821 via one or more conduits 822 or 860. The liquor may include cooking agents or additives as described above. These cooking agents or additives may be the same or different from those introduced into subsystem 710. For example, a kraft cooking liquor containing a high concentration of sulfide ions, ie, high sulfide, is introduced into subsystem 710 and a kraft cooking liquor containing a low concentration of sulfide ions, ie, low sulfide, is chipped into subsystem 810. May be introduced. In another example, a polysulfide-type additive is added to subsystem 71.
0, and an anthraquinone-type additive may be introduced into subsystem 810.

The pressure in the tank 821 can be monitored and controlled by a pressure indicator / controller 825. Excess pressure is supplied via conduit 826 to, for example, a conventional non-condensable gas (NCG) treatment system or to a pretreatment vessel 81.
Can be released. Further, the pressure controller 82
5 is used to regulate the pressure in tank 821 and US Pat.
The pressure can be changed so as to cause pressure pulsation as described in 57,461 and 4,743,338.

The slurry is discharged from the tank 821 to the conduit 850. This emission is generated by the Diamondback®
It can be performed without using agitation or vibration as in a tip bottle, or can be performed with agitation or vibration as in the conventional case. Conduit 850 introduces the slurry to the inlet of pump 851.
Pump 851 may be similar to pump 85, but is typically of higher pressure. Additional liquid can be introduced into conduit 850 via conduit 854 to facilitate introducing slurry to pump 851. The slurry discharged from pump 851 is sent to subsystem 910 via conduit 886.

The slurry in the conduit 886 is supplied to the liquid separation device 9
87 to the subsystem 910. This separator 987 is similar to the device 887 and the device 87 (of FIG. 4). The liquid removed from the device 987 is
1 can be returned to the subsystem 810, or can be used elsewhere in the pulp mill via conduit 988. When returning liquid to subsystem 810 via conduit 911, additional liquid or drug is added to this liquid via conduit 912, which is heated via indirect heat exchanger 890 via conduit 891 and pressurized by pump 889. And then into conduit 821 via conduit 822 or 860 or conduit 8
This liquid can be reintroduced into conduit 850 via 54. The liquid in conduit 911 can be introduced into subsystem 710 using, for example, common plumbing with conduit 88 or 82. Subsystem 810 may include a liquid storage tank similar to tank 353 shown in FIG. Thus, by using the heater 890 and the drug addition 912, the
The slurry of cellulosic material, which is transferred via conduit 886 to 10, can be heated to any desired temperature while being treated with the drug. For example, if the slurry in conduit 886 is heated to about 90 ° C. or higher in the presence of alkali or sulfide, some amount of cellulosic material will remain in conduit 886 before the slurry is introduced into subsystem 910. Preprocessing is performed. Of course, other agents may be used in conduit 886 at lower temperatures.

The chips taken into the separator 987 are in the tank 9
21. The tank 921 may be a tank similar to the tank 81, but may be a tall tank similar to the tank 821 or a tank similar to the tank 321 in FIG. Vessel 921 may be at atmospheric pressure or at a pressure above atmospheric pressure (eg, 0.2 to 10 bar (gauge), preferably 0.5
５5 bar (gauge)). Tank 9
The temperature of 21 ranges from 50 to 300C, but is usually between about 50 and 150C, preferably between about 80 and 120C. The liquid may be introduced into the tank 921 via one or more conduits 922 or 960. The introduced liquor may include cooking agents or additives as described above. These cooking chemicals or additives may be the same as or different from those introduced into subsystem 710 or 810. For example, a kraft cooking liquor containing a high concentration of sulfide ions, i.e., high sulfide, is introduced into the subsystem 810 and a kraft cooking liquor containing a low concentration of sulfide ions, i.e., low sulfide, is chipped into the subsystem 910. May be introduced. In another example, a polysulfide-type additive is added to subsystem 7
The anthraquinone-type additive may be introduced into subsystem 810 and the kraft white liquor may be introduced into subsystem 910 chips. Each of these liquids can be separated from each using liquid separators 887 and 987.

The slurry is discharged from the tank 921 to the conduit 950. This emission is generated by the Diamondback®
It can be performed without using agitation or vibration as in a tip bottle, or can be performed with agitation or vibration as in the conventional case. Conduit 950 introduces the slurry to the inlet of pump 951.
The pump 951 may be similar to the pumps 85 and 851, but is typically of a higher pressure specification. Conduit 960
Further liquid can be introduced into conduit 950 via via to facilitate introduction of slurry into pump 951. The slurry discharged from pump 951 may be passed through conduit 986 for further processing, for example, in a digester (ie, a continuous or batch digester), or subsystem 810 or 9
10, or for further processing in a subsystem similar to subsystem 310 of FIG. However, the processing performed in subsystems 710, 810, 910 does not
No further "pulp making operation" needs to be performed, as it is sufficient to produce a substantially completely cooked pulp slurry in zero. The pulp in conduit 950 can be sent directly to a washing and / or bleaching step.

As with subsystems 310, 810, and 910, excess fluid is routed through subsystem 91 via conduit 913.
Can be returned to zero. Additional liquid or drug is added to this liquid via conduit 914, which is heated via indirect heat exchanger 990 via conduit 991 and pressurized with pump 989,
Thereafter, via conduit 922 to tank 921 or conduit 96
This liquid can be reintroduced into conduit 950 via zero. The liquid in conduit 913 may be connected to subsystem 710 or 8
10 can be introduced using, for example, common piping (not shown) with conduits 88 or 82, or common piping with conduits 911 or 822, or a similar conduit.
Subsystem 910 may also include a liquid storage tank similar to tank 353 shown in FIG.

Thus, by using the heater 990 and the drug addition 914, the
The slurry of cellulosic material that is transferred via 86 to subsequent subsystems or digesters can be heated to any desired temperature while being treated with the chemical. For example, conduit 986
When the slurry therein is heated to above about 90 ° C. in the presence of alkali or sulfide, the slurry stays in conduit 986 before being introduced into subsequent processing equipment, for example, digester 11 of FIGS. Some pretreatment of the cellulosic material takes place during this time. Of course, conduit 986 may use lower or higher temperatures, as well as other agents.

Although each of the indirect heat exchangers 90, 890, 990 has a separate heat source, for example, a separate steam source, hot water source, or normally discharged hot waste liquid source, the heat exchangers 90, 890, 990 Can also be supplied with heat from a common heat source 915. As the heat source 915, for example, high-temperature waste liquid or steam (low, medium, high-pressure steam)
After being introduced into the heat exchanger 990, the remaining heat is sent to the heat exchanger 890 via the conduit 992. Heat exchanger 8
The remaining heat from 90 can be sent to heat exchanger 90 via conduit 892. Any residual heat in conduit 92 may be used or discarded as needed elsewhere in system 710, 810, or 910 or elsewhere in the pulp mill. For example, the liquid in conduit 92 and any residual heat contained therein may be transferred via conduits 82 or 822 to tanks 81 or 82.
The heat that is introduced and available in 1 can be recovered and reused as much as possible.

Using the apparatus 610 shown in FIG. 5, a countercurrent flow of processing solution can be established between each of the subsystems. For example, liquid from an upstream processing step may be
Can be returned to subsystem 910 via subsystem 910, and fluid from subsystem 910 can be returned to subsystem 8 via conduit 911.
10, and fluid from subsystem 810 can be returned to subsystem 710 via conduit 88. Further, some or all of these liquids are transferred to conduit 888.
And 988 for use elsewhere.

Additives at 788,912,914 were sodium hydroxide, sodium sulfide, polysulfide, anthraquinone, or equivalents or derivatives thereof, surfactants, enzymes, or chelating agents, or combinations thereof. Preferably, it is For example, if different processing chemicals are added to 788, 912, and 914, different processing is performed in sections of 710, 810, and 910, respectively. For example, polysulfide can be added at 788, anthraquinone can be added at 912, and the chelating agent and enzyme can be added at 914. The conduits at 788, 912, 914 need not be provided at the locations shown in FIG.
It may be provided at a convenient place where permeation or other pretreatment can be easily performed simultaneously with transportation. For example, lines 788, 912, 9
14 may be added to lines 790, 891, 991 in front of heat exchangers 90, 890, 990, respectively.

In one preferred embodiment, the slurry is
To remove unwanted metal-containing compounds or metal ions from the cellulosic material. For example, in this embodiment, the drug added to the slurry is an acid and / or a chelating agent. The acid is preferably sulfuric acid, sulfur dioxide, acetic acid, formic acid, oxalic acid, peracid, caroic acid or an acid equivalent thereto, or an acid obtained by combining these. Acidic filtrate from a bleach plant can also be used as a source of acid. The pH of the solution during the acid treatment is usually p
H ranges from about 1 to about 7, but preferably has a pH of about 2 to about 4. The temperature of the acid treatment ranges from about 0 to about 150C, preferably from about 60 to about 90C. The treatment time of the acid treatment is 10 minutes to 6 hours, preferably about 30 to 120 minutes. After the acid treatment, a magnesium salt, such as magnesium sulfate, is added to replenish the cellulosic material with an amount of magnesium that is known to be beneficial under certain conditions.

The solution containing the chelating agent, ie, the polydentate ligand molecule, is preferably EDTA, DTPA, DTMPA or an equivalent thereof, or a combination thereof. The amount of chelating agent added is usually at most about 2 kg per ton of pulp and ranges from about 0.5 to 5 kg per ton of pulp. During the treatment with the chelating agent, the pH of the treatment solution is usually from about pH 2 to about 1
It is in the range of 0, but preferably at a pH of about 4 to about 8.
The temperature of the chelating agent treatment ranges from about 0 to about 150C, preferably from about 60 to about 110C. The treatment time of the chelating agent treatment is in the range of 10 minutes to 6 hours, but about 3 hours.
Preferably from 0 to about 90 minutes.

The chelating agent treatment step (Q) and the acid treatment step (A) are not mutually exclusive. That is, both types of processing can be performed, for example, while the slurry of the cellulosic material is being transferred continuously and in any order. Both processes can be performed repeatedly.
Both types of continuous processing may or may not include a purge or cleaning step between them. For example, to list some of the processing sequences that can be implemented in accordance with the present invention, the following sequences: AA, QQ, AQA, QA
Q, AAQ, QQA, AQQ, QAA, AAA, QQ
Q, AAQQ, and QQAA, but are not limited to these. Repeating or extending these processing sequences is readily understood by those skilled in the art and is also within the scope of the present invention. Also, in these sequences, a washing or purging step may or may not be inserted between successive processes.

In the embodiment shown in FIG. 5, the acid or chelating agent is added to conduits 782, 788, 912 and / or 9
14, but the acid or chelating agent is added to subsystem 710 via conduit 782 and to subsystem 8
Preferably, 10 is introduced via conduit 912. If an acid or chelating agent is added to subsystem 810, for example, a digester supplied via conduit 986 with or without a conventional high pressure feeder (not shown)
The metal removal treatment can be performed immediately after the alkali treatment of the subsystem 910 before the alkali digestion in the above.

For example, after processing or transfer in subsystem 710, an acid or chelator is added to conduit 912,
Subsystem 81 via 854, 860, or 882
0 can be introduced. The acid-treated / chelated slurry is pressurized by a pump 851 and sent to a liquid separator 987 via a conduit 886. The processing liquid is a liquid separator 98
7 and returned upstream of the inlet of the pump 851 and is preferably removed from the system via conduit 988. The metal-containing stream removed via conduit 988 can be sent to other processing or disposal steps of the pulp mill or a suitable form of conventional metal recovery process. Conduit 988
The liquid removed via can be removed from the conduit 911 simply by a branch line or can be removed through a liquid separator, for example, an in-line withdrawal device (not shown). Conduit 9
The liquid in 88 can also be removed directly from liquid separator 987. The amount of liquid withdrawn via conduit 988 is
Replacing, or "replenishing," liquids introduced via 2,854,860, and / or 822, for example, water, wash filtrate, black liquor, or bleach plant waste, among other available liquids Can be. The replenishment of the acid or chelating agent is performed via one or more conduits 912, 854, 860, and / or 822, with or without replenisher.

Further, in accordance with the present invention, an acid or chelating agent is introduced via conduit 782 or conduit 788 and a metal removal treatment is performed in subsystem 710 before the alkali treatment is performed in subsystem 910, and a second metal removal treatment is performed in subsystem 710. Processing can occur in subsystem 810. The second treatment of subsystem 810 may be a second acid or second chelation treatment, or if the treatment of subsystem 710 is an acid treatment, the treatment of subsystem 810 may be a chelation treatment;
The reverse is also acceptable.

In addition, since the pH of an acid or chelation treatment is usually distinctly different from the pH of an alkali treatment (eg, an alkali treatment is usually performed at a pH above 8, often at a pH above 10), In one embodiment of the present invention, in order to avoid excessive consumption of acid, chelating agent and / or alkali, washing or neutralizing treatment is carried out in the second step after the acid or chelating treatment in the first step. Then, an alkaline solution is introduced in the third step. FIG.
The acid or chelate treatment can be performed in subsystem 710, some neutralization washing or impregnation of the cellulosic material can be performed in subsystem 810, and the alkali treatment can be performed in subsystem 910.

For example, an acid or chelating agent is
2, and the pressure of the acid-treated / chelated slurry is increased by a pump 85.
7 can be sent. The processing liquid is withdrawn via the liquid separator 887 and returned to the inlet of the pump 85, preferably
It is removed from the device via conduit 888. The metal-containing stream removed via conduit 888 can be sent to other processing or disposal steps in the pulp mill or any suitable form of conventional metal recovery process. The liquid removed via conduit 888 can be simply removed from conduit 88 by a branch line or can be removed through a conventional liquid separator, for example, an in-line liquid drawer (not shown). The liquid in conduit 888 can also be taken directly from liquid separator 887. The amount of liquor withdrawn via line 888 is the amount of liquor introduced via line 788 and / or 782, such as water, wash filtrate, black liquor, or bleach plant effluent, among other available liquors. An alternative, or “supply,” can be made. Replenishment of the acid or chelating agent is performed via conduit 788 or 788 or both, with or without replenisher.

After acid or chelation in subsystem 710, subsystem 810 can be used to wash or neutralize the slurry before introducing the slurry to an alkaline treatment in subsystem 910. For example, prior to introducing the slurry into liquid separator 987, a substantially neutral to alkaline, preferably metal-free, liquid may be applied to conduit 912 or conduits 854, 860, or 8;
22 into the slurry, through tank 821 and through conduit 8
The slurry can be washed while passing through 50 and 886, or the pH of the slurry can be increased. The neutralized or pH adjusted liquid is removed from the slurry via liquid separator 987 and returned to upstream of pump 851 via conduit 911 or via conduit 981.
8 can be removed. Again, the liquid removed via conduit 988 can be removed simply at the branch, or through a liquid separator (eg, a conventional in-line withdrawal device), or directly from liquid separator 987.

After the metal removal treatment in subsystem 710 and the washing or neutralization treatment in subsystem 810, in subsystem 910, the cellulosic material is washed with an alkaline cooking agent such as kraft white liquor, green liquor, or black liquor (as described above). ) With or without additives, so that subsequent formal cooking minimizes excess drug usage based on consumption of acid and / or chelating agent by alkali.

FIG. 6 shows another preferred apparatus for implementing the preferred method of the present invention. Using the apparatus of FIG. 6, a comminuted cellulosic fiber material (usually about 5-20
%) Of the slurry is sent to any point in the fiber transport line of the pulp mill, such as from a wood yard to a digester, using an intermediate booster pump in series. Each pump is provided in connection with a station (treatment tank), and each station is provided in connection with a solid / liquid separator (usually a conventional solid / liquid separator provided at the top of the station). Separate and circulate the stream. Infiltration and other pretreatments are performed simultaneously during the transfer of the cellulosic material in the circulation line (ie, from one pump to its associated station). These lines are extremely long (eg, 100 yards or more and up to about 1/2 mile) and can be easily pre-treated and infiltrated. Preferably, a heat exchanger is used in the return line, and one, more or all of the transfer stations may be provided with deaerators. An eductor (ejector) can be used in place of the flash tank and / or control valve to drain and reduce pressure.
In addition, pressure pulsing can occur in conjunction with the pump and station configuration. The pump boosts the slurry by at least 5 bar (typically at least about 10 bar). Also, a wide range of treatment agents such as sodium hydroxide, sodium sulfide; polysulfides,
Anthraquinone, or equivalents or derivatives thereof; surface active agents, enzymes, or chelating agents; or combinations thereof, can also be used, but are preferably added upstream of the pump.

The chip slurry 1000 can be formed by conventional procedures (including slurrying with hot steam), and the first, second, and third booster pumps 1001, 10
02, 1003 are connected in series. Pump 100
1 to 1003 are stations (tanks) 1004, 100
5,1006 are provided in connection with each. Each station 1004 to 1006 is provided with a liquid / solid separator associated therewith. In the embodiment shown in FIG. 6, the separators 1007, 1008, 1009 are shown installed on top of the stations (processing tanks) 1004 to 1006. However, these separators can also be installed at other locations, for example, at the bottom.

Preferably, the medicament is added to the slurry at many different points in the device, for example, at points upstream of each pump 1001-1003. This corresponds to 1010,
These are shown schematically at 1011 and 1012 at the drug addition. The same or different agents can be added at 1010-1012. Preferably, at least some of the agents are sodium hydroxide, sodium sulfide; polysulfide, anthraquinone, or equivalents or derivatives thereof; surfactants, enzymes, or chelating agents; or a combination thereof. . In the embodiment actually shown in FIG.
2 is performed, for example, with a white liquor containing AQ (for example,
Vessel 1006 is a continuous digester).

Rather than establishing a circulation line as shown in FIG. 5, circulation in the embodiment of FIG. 6 is performed in a preferred manner to create a simulated countercurrent flow of the comminuted cellulosic fibrous material and the liquid. . In FIG. 6, three stations are shown,
Any number of radix stations can be provided.
In the embodiment of FIG. 6, the liquid removed from separator 1007 in line 1013 is used elsewhere in the mill or is sent to processing for reuse. The liquid removed from the separator 1008 is sent to a point upstream of the pump 1001 on line 1014 (eg, diverted to a slurrying station 1000 or a feed to the pump 1001 by a valve 1015) and to a third separator 1009. The separated liquid is in line 10
Circulated upstream of the pump 1002 at 16, for example, valve 1
At 017, a branch is made to the first station 1004 and / or just upstream of the pump 1002. Fresh liquid is added from liquid source 1012 to the bottom of tank 1005 or to the suction port of pump 1003.

The return lines 1014 and 1016 can be provided with conventional indirect heat exchangers 1018 and 1019, where the temperature change of the liquid is at least 5 ° C. In the illustrated embodiment, the liquid is heated, but in some circumstances, the liquid may be cooled instead of being heated. Indirect heat exchanger 1020 can also be used in conjunction with drug addition 1012.

The liquor can be withdrawn from the third station (if this is a digester, the liquor is, for example, black liquor) using a conventional eductor (ejector) instead of a flash tank and / or a control valve. Each pump 1001
Preferably, 1003 boosts the slurry to a pressure of at least 5 bar (typically at least about 10 bar).

A deaerator may be provided at one, a plurality, or all of the stations 1004. this is,
This is schematically illustrated in the gas removal lines 1023 to 1025 of FIG. The deaerator uses a conventional deaerator to separate the separator 1.
007-1009, its entry line, and the like.

FIG. 7 schematically shows an apparatus for feeding a continuous digester similar to the apparatus shown in FIG. Some of the notable differences between the apparatus of FIG. 7 and the method performed by it and the apparatus of FIG. 3 and the method performed by it are: Return lines, return conduits to introduce liquid directly into the tip tube (by bypassing the surge tank), and recirculation from one or each of the slurry pumps (including the first pump) to each outlet and finally to their inlets To provide a recirculation conduit (e.g., connected between the surge tank and the tip tube for the first pump) to establish the desired recirculation flow, especially at startup.

Although FIG. 7 shows a continuous digester, it should be understood that the present invention is also applicable to a batch digester system. The apparatus shown in FIG. 7 is a supply apparatus 1110 for supplying the digester 1111. The supply device 1110 includes an airlock type chip supply screw 1112 for receiving the wood chips 20 and a chip bin 1121. Feed screw 1112 is disclosed in U.S. Pat.
Preferably, the apparatus is disclosed in U.S. Pat. No. 66,418, and the bottle 1121 is sold as a Diamondback (R) steam treatment tank or bottle as described above. Other types of conventional steaming vessels, such as a horizontal screw conveyor or VibraBin with vibrating outlet, can also be used in place of the diamond backbin.

Similar to the device shown in FIG. 3, the device shown in FIG. 7 includes a metering device 1123, eg, a tip meter, a vertical conduit 1126, eg, a tip tube, a liquid storage tank 1153, eg, a liquid surge tank. Also, as shown in FIG. 3, the device of FIG. 7 includes a first pump, ie, a pump device 1151, and a second pump, ie, a pump device 1151 ′. Again, these pumps can be any type of pump or pump device that pressurizes and transports a slurry of the comminuted cellulosic fibrous material and the liquid. One preferred pumping system is a hydrostal screw feed type pump manufactured by Wemco Pump Company of Salt Lake City, Utah (http: //www.wemcopum).
p.com/Products/hidrostal/details.htm/) or a pump manufactured by Lawrence Pumps, Inc. of Lawrence, Mass. (http://www.lawrencepumps.com/).
3, the inlet of the pump 1151 is operatively connected or physically directly connected to the outlet of the vertical conduit 1126, and the outlet of the pump 1151 is operatively connected to the inlet of the pump 1151 ′. Or they are physically connected. The outlet of the pump 1151 ′
Operatively connected to the inlet of digester 1111 via
Excess liquid is fed from digester 1111 to feeder 1110,
It is returned via conduit 1135 from the digester inlet or from another available source of liquid associated with the digester.

Although not shown in FIG. 7, those skilled in the art will recognize that one or more pumps 1151 supply two or more pumps 1151 'and one or more pumps 1151'. It will be appreciated that this may be implemented by providing to 1111. This mode of operation is particularly suitable for feeding to a plurality of batch digesters, but is also applicable to feeding to two or more continuous digesters. One of the devices that can be used to divert flow from one conduit to two or more conduits is shown in FIG. As will also be appreciated, the present invention is directed to U.S. Patent No. 5,795,43.
Since the functions of the invention disclosed in Japanese Patent Publication No. 8 can be incorporated, the entire text is cited in this specification as a reference.

The liquid in conduit 1135 is returned to the supply 1110 at various points. The liquid in conduit 1135 is
To the tip tube 1126 via conduit 1182, or to the tank 1153 via conduit 1183, or to conduit 11
It is preferred to return to tank 1121 via 84. Conduit 113
The liquid in 5 is usually at a temperature higher than 100 ° C., and the tip tube 1126 and the tank 1153 operate at approximately atmospheric pressure, ie, −1 to +1 bar (gauge) (ie, 0 to 2 bar (absolute)). Therefore, some form of cooling 1136 is provided to avoid undesirable rapid evaporation (ie, "flashing"). This cooling device is preferably an indirect liquid / liquid cooling heat exchanger, which cools the returned liquid below the flashing temperature. Conduit 11
The cooling medium passed to 37 is typically a low temperature liquid stream available in pulp mills. One preferred cooling medium is fresh water, which has a heat exchanger 1136 via conduit 1137.
At a certain temperature and is withdrawn via conduit 1138 at a higher temperature. Cooking liquor, for example, kraft white liquor, green liquor, or black liquor, can also be used as a cooling medium for heat exchanger 1136 (eg, via conduit 1150). A bypass conduit 1135 'can also be used to divert liquid around the heat exchanger 1136 when the heat exchanger is not needed or when it is being repaired.

The liquid level in the tank 1153 is usually controlled by a liquid level control mechanism, for example, a liquid level control mechanism using a dp cell liquid level indicator or a gamma ray type liquid level indicator (not shown). The level of tank 1153 is typically controlled by varying the flow of liquid from pump 1160, a branch line 1181 that feeds a make-up pump. Pump 1160 pressurizes this excess liquid and supplies it to the top of digester 1111 via conduit 1161.

[0126] The liquid in conduit 1135 can be introduced upstream of pump 1151 via conduit 1163 with or without heating or cooling. The conduit 1163 can be provided with a valve F. The advantage of introducing pressurized liquid from the conduit 1135 upstream of the pump 1151 has been discussed above in the description of FIG. The present invention also provides a pump 1151.
Conduit 11 with valve E between the outlet of
Preferably, 56 is provided and liquid can flow from line 1156 to line 1154.

Fluid is supplied to conduits 1144 and 1144 during normal operation of the device, or during shutdown or startup.
It can be introduced into conduits 1134 and 1135 via 145. For example, a weak black liquor or “cold blow” liquor from pump 1140 is introduced into conduits 1134 and 1135 to clean the line during shutdown, or during normal operation, eg, for liquor / wood ratio control or black liquor pretreatment. Additional liquid required for the application can be introduced into these lines. Cooking liquor, such as kraft white liquor, green liquor, black liquor, orange liquor or liquids containing strength or yield enhancing additives, such as anthraquinone, polysulfide, chelating agent, surfactant, sulfur, or derivatives thereof or Equivalents can be added to the supply via conduit 1150 and pump 1152. The liquid in conduit 1150 is preferably added to tip tube 1126 as shown, but can also be added to conduit 1134 or 1135.

The device shown in FIG. 7 comprises a number of valves, whether automatic control valves or manual, which shut off the flow of liquid and its pressure from each other. Valve A shuts off the outlet of pump 1151 from the inlet of pump 1151 '. Valve B shuts off the outlet of pump 1151 'from digester 1111. Valve C in conduit 1134 is connected to digester 1111
The supply conduit to the vessel is isolated from the digester, and valve D in conduit 1135 isolates return conduit 1135 from digester 1111.
These valves are particularly important during upset conditions where hot pressurized liquid associated with digester 1111 is supplied from low pressure feeder 1110 and from nearby personnel and nearby machinery. Cut off.

Valves AF can also be used, together with other selected valves, to assist in the start-up and shutdown procedures and to stop fluid circulation. For example, closing valve A and opening valve E in conduit 1156 will start pump 1151, causing closed circulation around pump 1151 to flow through conduit 1
156 can be established. Similarly, when valve A is closed and valves C, D and F are opened and pump 1151 'is started, circulation around pump 1151' is via conduit 1134, the top of digester 1111, conduit 1135, via conduit 1163. Can be established. (Pump 115
(Circuit 1 can be shut off from digester 1111 by inserting conduit 1170 with appropriate valve G into conduit 1170 between conduits 1134 and 1135).

The conduits 1156, 1154 (and preferably the shutoff valves A and E) and the associated piping to the other components
It serves as means for circulating the liquid from the pump 1151 to its inlet. Although the conduit is shown as such a means, it should be understood that any conventional structure capable of performing this circulation can be used, for example, tanks, ejectors, pumps, valves, ducts, heat exchangers, etc. is there.

The interruption of these circulations is particularly advantageous during start-up and shutdown, in which case these interruptions can be maintained individually. For example, prior to introducing wood chips at startup, two pumps 1151 and 1151 'are operated to circulate one around pump 1151 via conduit 1156, the digester top and conduits 1134 and 1135. A second circulation around the pump 1151 'can be established. In this way, the proper operation of each pump 1151, 1151 'can be assured and the pressure and temperature of each circulation can be separately shut off and established. For example, the temperature and pressure of the circulating liquid in conduits 1134 and 1135 may be increased to digester operating conditions, eg, 7-15 bar (gauge), 100-160 ° C., while simultaneously circulating the pump 1151 and the circulation associated with conduit 1156. The temperature is lower, for example, 1-3 bar (gauge), 60-1.
It can be maintained at 20 ° C. Next, if the conditions of each circulation match, for example, when the liquids in conduits 1134 and 1156 are both about 10 bar (gauge) and 120 ° C., gradually open valve A and simultaneously close valve E gradually. Thus, the chips can be introduced into the supply device 1110. A similar situation occurs during shutdown or digester 11
Occurs when the system must be disconnected from the system to repair 11 and / or supply device 1110.

The supply device 1110 may be a centrifugal separator for removing sand and debris, such as a sand separator; a liquid / chip separator, for example, an in-line liquid withdrawal device; For example, a level tank can be provided as needed. One or all of these devices may be omitted from the embodiment shown in FIG.

The supply device 1110 has an integrated tip tube and a surge tank, and the simplified structure of other supply devices is also described in US Patent Application No. 09 / 520,761 filed on March 7, 2000 (Patent Summary). (10-1302). This disclosure is incorporated herein by reference in its entirety.

FIGS. 8 to 10 show another embodiment of the present invention for branching the flow of slurry in a pipeline. 8 shows an elevation view, FIG. 9 shows a top view, and FIG. 10 shows an elevation view from the right side. Apparatus 1 shown in FIGS.
200 is a static "flow divider" or "flow splitter"
For example, the conduit 34 of FIGS. 1 and 2, the conduit 252 or 234 of FIG. 3, the conduits 86 and 886 of FIGS. 4 and 5, or the corresponding conduit of FIG. 6, or the conduit of FIG. Can be inserted into conduit 1134.

The static flow splitter 1200 has an inlet 120 for the slurry flow of the comminuted cellulosic fibrous material and the liquid.
1 and two or more outlets 1202 and 1203.
The inlet and outlet are preferably circular in cross section, but may be non-circular, eg, elliptical, rectangular, square, or triangular, depending on the needs of the installation. Apparatus 1200 includes a chamber 1204 that is used to receive slurry from inlet 1201 and discharge the slurry to two or more outlets 1203, 1204. The cross-section of the chamber 1204 can be any suitable shape, for example, circular, oval, rectangular, square, or triangular, but the shape of the chamber limits the area where the cellulosic material in the slurry can reside. Is preferably
For example, sharp corners are avoided. As shown in FIG. 8, one of the preferred shapes of the chamber 1204 is substantially triangular, and the angle at which the center line of the outlets 1202 and 1203 converges on the center line of the inlet 1201 is, for example, about 30 to 60 degrees, for example. It is about 45 °.

The chamber 1204 also includes one or more internal baffle plates 1210, 1211 (shown by dotted lines) in FIG.
To assist in directing the flow of the slurry.
These baffle plates 1210 and 1211 are
Together define a triangle, which is located opposite the entrance 1201 of the device 1200. Baffle plates 1210, 121
One end is the walls 1213, 1214 of the chamber 1204
Can be fixed by welding. In the embodiment shown in FIG. 8, the cusp 1215 of the substantially triangular baffle plate structure 1210, 1211 is arranged in substantial alignment with the inlet 1201. The flow splitter 1200 is static, ie, has no moving parts (although the position of the baffle plate structures 1210, 1211 can be adjustable).

The dimensions of the device 1200 will vary depending on the given or desired size and production rate of the device in which it is used. The dimensions, eg, diameter, of the inlet 1201 and outlets 1202, 1203 range from 2 inches to 10 feet. For example, the inside diameter of the inlet and outlet is about 10 inches.
The dimensions of the chamber 1204 are substantially determined by the dimensions of the inlet and outlet, and also range from about 2 inches to about 10 feet, for example, the chamber 1204 shown in FIGS.
Is about 13 inches wide.

Apparatus 1200 is typically made of a suitable material that can withstand the high temperatures (eg, above 400 ° F.), high pressures (eg, above 300 psig), and corrosive (acidic or alkaline) slurries normally handled in pulp and paper mills. Manufactured, these materials are, for example, metals and high-performance plastics. However, this device is preferably made of metal, especially steel, and is weldable stainless steel, for example 304L (ASTM-A in ASTM symbol).
240-304L) or its equivalent or higher.

In use, the inlet 1201 is connected to the conduit 3
4,252,234,86,856,1134, one of the outlets 1202 is connected to the same conduit as above,
The other outlet 1203 is connected to a conduit leading to the same or another digester (batch or continuous). Exit 1
When only two of the 202 and 1203 are provided, it is preferable that half of what flows into the inlet goes to each outlet. However, it is also possible to change the size and arrangement of the baffle plates 1202 and 1203 so that a larger flow rate flows from one of the outlets 1202 and 1203 than the other.

As described above, in the broadest aspect of the present invention, there is provided an apparatus and a method for carrying out multistage transfer and treatment of a comminuted cellulose fiber material while economically recovering and reusing energy including thermal energy. Is done.

It is to be understood that the present invention has been described in terms of what is presently considered to be the most practical and preferred embodiment, so it is to be understood that the invention is not limited to the disclosed embodiments, and, The intention is to cover all the spirit and many equivalent modifications and equivalent arrangements falling within the scope of the appended claims.

[Brief description of the drawings]

FIG. 1 illustrates a typical prior art apparatus for feeding a slurry of comminuted cellulosic fiber material to a continuous digester.

FIG. 2 shows another prior art apparatus for supplying a slurry of a comminuted cellulosic fiber material to a continuous digester.

FIG. 3 illustrates a typical embodiment of the present invention of an apparatus for supplying a slurry of a comminuted cellulosic fiber material to a continuous digester.

FIG. 4 is a diagram showing another embodiment of the device of the present invention.

FIG. 5 is a diagram showing another embodiment of the device of the present invention.

FIG. 6 is a schematic diagram of another apparatus that can be used to carry out the method of the present invention.

FIG. 7 is a schematic diagram of one other exemplary embodiment of the present invention of an apparatus for supplying a slurry of comminuted cellulosic fiber material to a digester.

FIG. 8 is a side view of an exemplary flow splitter of the present invention, with a portion of a proximal wall of the flow chamber cut away to show the interior thereof.

FIG. 9 is a top view of the flow splitter of FIG.

FIG. 10 is a side view of the flow splitter of FIG.

[Explanation of symbols]

10, 110, 210, 310, 410, 510, 71
0, 810, 910, 1110 ... supplying device, 11, 11
11 digester, 12, 14 screen, 13 digester inlet, 20 milled cellulose fiber material, 21, 121,
221, 321, 821, 921, 1121... Tank (bottle), 22, 28, 29, 30, 33, 34, 35, 3
6,38,41,43,52,54,55,56,6
0,61,63,82,82 ', 84,86,88,9
2,129,234,235,250,252,23
4,254,782,788,790,822,85
0,854,860,886,888,891,89
2,911,912,913,914,922,95
0,960,986,988,991,992,101
3,1014,1016,1023,1024,102
5,1126,1134,1135,1135 ', 11
37, 1138, 1144, 1145, 1150, 11
54, 1156, 1161, 1163, 1170, 11
81, 1182, 1183, 1184 ... conduit, 23, 1
23, 223, 1123: Measuring device, 24, 224: Pressure shut-off device, 25: High-pressure steam treatment tank, 26, 12
6, 226, 226 ', 1126 ... chute, 27 ... high-pressure transfer device (high-pressure feeder), 31, 32, 42, 5
1,62,64,85,89,251,251 ', 88
9,851,951,989,1001,1002,1
003, 1140, 1151, 1151 ', 1152
1160: pump, 37, 237: sand separator, 39: in-line liquid extracting device, 40, 53, 253, 35
3,1153 ... Level tank, 58,65,66,67
... Valve, 59 ... Pressure indicator, 68 ... Pressure switch, 80 ...
Chip storage area, 81: storage tank, 83: discharge device, 87, 8
87,987 ... liquid separator, 90,890,990,1
018, 1019, 1020, 1136 ... heat exchanger, 8
23 ... liquid level, 825 ... pressure controller, 915 ...
Heat source, 1000 ... chip slurry, 1004, 100
5,1006 ... Station (tank), 1010,101
1,1012 ... drug injection point, 1007,1008,10
09 ... separator, 1022 ... ejector, 1112
... Supply screw, 1200 ... Flow splitter, 1201 ...
Flow branch inlet, 1202, 1203 Flow branch outlet, 1204 Flow branch chamber, 1210, 12
11. Flow baffle baffle plate, 1212, 1213, 1
214 ... flow branch wall, 1215 ... flow branch point.

[Procedure amendment]

[Submission date] June 26, 2001 (2001.6.2
6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Title: Method and apparatus for supplying cellulose fiber material to treatment tank

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008] One of the common units of measure that indicates the relative amount of solids in a slurry containing solids and liquids is the "liquid / solid ratio". In the present application, this ratio is the ratio of the volume of liquid transferred to the volume of cellulose or wood transferred.
Typical conventional centrifugal liquid pumps are limited to pumping liquids having a maximum solids content of 3%. This solid content of 3% means that the liquid / solid ratio is about 3 %.
Equivalent to 2 . In the slurry pump of the present invention, the liquid / solid ratio of the pumped slurry is usually 2 to 10, preferably 3 to 7, and most preferably 3 to 6. In other words, the slurry pump of the present invention transfers a slurry having a solids content that is much greater than can be handled by conventional pumps.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

The method also includes (d) establishing a recirculation loop between each pump outlet and inlet during startup. For example, the first valve in the recirculation loop,
A second valve can be provided between each pump outlet and the treatment tank, wherein step (d) opens the first valve during start-up and the second valve is at least partially (eg,
(Completely) closed, and then the method may further comprise the step of (e) closing the first valve and opening the second valve after startup. In this method, one of the pump inlets (preferably,
Return the liquid to the first of the series connected pumps)
The method may include partially cooling the return liquid (eg, with an indirect liquid / liquid heat exchanger) so that the return liquid has a temperature below the flash temperature during handling.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0083

[Correction method] Change

[Correction contents]

The slurry discharged from the pump 85 is transferred to the subsystem 310 via the conduit 86. The subsystem 310 depends on the layout of the pulp mill,
Near subsystem 410 , ie, subsystem 4
It can be located within about thirty feet of ten , or at a significant distance from subsystem 410 , such as more than one-half mile. Therefore, conduit 8
6 is indicated by a broken line to indicate such an assumed distance between the subsystem 410 and the subsystem 310 .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0101

[Correction method] Change

[Correction contents]

Using the apparatus 610 shown in FIG. 5, a countercurrent flow of processing solution can be established between each of the subsystems. For example, the liquid from the processing steps of the lower flow conduit 913
Can be returned to subsystem 910 via subsystem 910, and fluid from subsystem 910 can be returned to subsystem 8 via conduit 911.
10, and fluid from subsystem 810 can be returned to subsystem 710 via conduit 88. Further, some or all of these liquids are transferred to conduit 888.
And 988 for use elsewhere.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

For example, after processing or transfer in subsystem 710, an acid or chelator is added to conduit 912,
Subsystem 81 via 854, 860, or 822
0 can be introduced. The acid-treated / chelated slurry is pressurized by a pump 851 and sent to a liquid separator 987 via a conduit 886. The processing liquid is a liquid separator 98
7 and returned upstream of the inlet of the pump 851 and is preferably removed from the system via conduit 988. The metal-containing stream removed via conduit 988 can be sent to other processing or disposal steps of the pulp mill or a suitable form of conventional metal recovery process. Conduit 988
The liquid removed via can be removed from the conduit 911 simply by a branch line or can be removed through a liquid separator, for example, an in-line withdrawal device (not shown). Conduit 9
The liquid in 88 can also be removed directly from liquid separator 987. The amount of liquid withdrawn via conduit 988 is
Replacing, or "replenishing," liquids introduced via 2,854,860, and / or 822, for example, water, wash filtrate, black liquor, or bleach plant waste, among other available liquids Can be. The replenishment of the acid or chelating agent is performed via one or more conduits 912, 854, 860, and / or 822, with or without replenisher.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0110

[Correction method] Change

[Correction contents]

For example, an acid or chelating agent is
2, and the pressure of the acid-treated / chelated slurry is increased by a pump 85.
7 can be sent. The processing liquid is withdrawn via the liquid separator 887 and returned to the inlet of the pump 85, preferably
It is removed from the device via conduit 888. The metal-containing stream removed via conduit 888 can be sent to other processing or disposal steps in the pulp mill or any suitable form of conventional metal recovery process. The liquid removed via conduit 888 can be simply removed from conduit 88 by a branch line or can be removed through a conventional liquid separator, for example, an in-line liquid drawer (not shown). The liquid in conduit 888 can also be taken directly from liquid separator 887. The amount of liquor withdrawn via line 888 is the amount of liquor introduced via line 788 and / or 782, such as water, wash filtrate, black liquor, or bleach plant effluent, among other available liquors. An alternative, or “supply,” can be made. Replenishment of the acid or chelating agent is performed via conduit 788 or 782 or both, with or without replenisher.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

[0133] supplying device 1110, formed by integrating a chip tube and the surge tank, and other simplified structure for the supply device is also disclosed in the specification of U.S. Patent Application Serial No. 09 / 520,761, filed March 7, 2000 It can be prepared as follows. This disclosure is incorporated herein by reference in its entirety.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The static flow splitter 1200 has an inlet 120 for the slurry flow of the comminuted cellulosic fibrous material and the liquid.
1 and two or more outlets 1202 and 1203.
The inlet and outlet are preferably circular in cross section, but may be non-circular, eg, elliptical, rectangular, square, or triangular, depending on the needs of the installation. The apparatus 1200 includes a chamber 1204 that receives slurry from an inlet 1201 and discharges the slurry to two or more outlets 1202 , 1203 . The cross-section of the chamber 1204 can be any suitable shape, for example, circular, oval, rectangular, square, or triangular, but the shape of the chamber limits the area where the cellulosic material in the slurry can reside. Is preferably
For example, sharp corners are avoided. As shown in FIG. 8, one of the preferred shapes of the chamber 1204 is substantially triangular, and the angle at which the center line of the outlets 1202 and 1203 converges on the center line of the inlet 1201 is, for example, about 30 to 60 degrees, for example. It is about 45 °.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

In use, the inlet 1201 is connected to the conduit 3
4,252,234,86,856,1134, one of the outlets 1202 is connected to the same conduit as above,
The other outlet 1203 is connected to a conduit leading to the same or another digester (batch or continuous). Exit 1
When only two of the 202 and 1203 are provided, it is preferable that half of what flows into the inlet goes to each outlet. However, it is also possible to change the size and arrangement of the baffle plates 1210 and 1211 so that a larger flow rate flows from one of the outlets 1202 and 1203 than the other.

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor C. Bertil Stromberg Edison Road, Glens Falls, New York, 12801 United States of America 4 (72) Inventor Tim SS. Pierce United States, 12803 New York State, South Glens Falls, Merritt Road 7831 F-term (reference) 4L055 CA05 CA07 FA22

Claims (23)

[Claims] An apparatus for producing a chemical cellulose from a comminuted cellulose fiber material comprises: a steam treatment tank for steam-treating the comminuted cellulose fiber material and degassing the same; A high-pressure vertical processing tank having an outlet at the bottom, and a pressurizing / transferring unit that pressurizes the slurry of the cellulose material from the steam processing tank and transfers the slurry to the processing tank, comprising an outlet and an inlet, respectively. One or more high-pressure slurry pumps provided below the top of the processing tank, and a pressure raising / transfer means, and circulating a liquid from an outlet of at least one high-pressure slurry pump to an inlet thereof. An apparatus comprising means. 2. The apparatus according to claim 1, further comprising a liquid return line from the top of the processing tank, wherein the return line is connected to an inlet or an outlet of the slurry pump during operation. An apparatus characterized by the above. 3. The apparatus according to claim 2, further comprising a heat exchanger located in said return line. 4. The apparatus according to claim 3, wherein said heat exchanger is a heat exchanger for cooling or heating the liquid in the return line. 5. The apparatus according to claim 3, wherein said heat exchanger is a liquid / liquid indirect heat exchanger, and a cooling liquid source connected to said heat exchanger for cooling liquid in said return line. An apparatus, further comprising: 6. The apparatus according to claim 1, wherein an inlet connected to the steam processing tank during operation, and an outlet connected to an inlet of the one or more slurry pumps during operation. An apparatus further comprising a slurrying tank having the same. 7. The apparatus according to claim 6, further comprising a liquid return line from the top of the processing tank, wherein the return line is connected to the slurrying tank during operation. . 8. The apparatus according to claim 7, further comprising a heat exchanger disposed on said return line. 9. Apparatus according to claim 8, wherein said heat exchanger is an indirect heat exchanger for cooling and heating the liquid in the return line. 10. The apparatus of claim 1, wherein said at least one pump is at least two pumps. 11. Apparatus according to claim 10, wherein each of said pumps comprises said circulating means. 12. The apparatus of claim 1, wherein said circulation means comprises a conduit having a first valve, and further comprising a second valve between said pump outlet and said processing tank. . 13. The apparatus of claim 11, wherein each of said circulation means comprises a conduit having a first valve, and further comprising a second valve between said pump outlet and said processing tank. apparatus. 14. The apparatus of claim 10, wherein the processing vessel comprises a first processing vessel, and further comprising a second processing vessel; a main conduit connected to the outlet of the at least one pump; A static flow splitter having two outlets; wherein the main conduit is connected to the flow splitter; one of the flow splitter outlets is connected to the first processing tank and the second processing tank. A device connected to another outlet. 15. The apparatus of claim 14, wherein the flow splitter comprises a chamber containing a substantially triangular static baffle plate structure, the triangular point substantially aligned with the inlet. An apparatus characterized by being located. 16. A method for supplying a comminuted cellulosic fiber material to the top of a treatment tank, comprising the steps of: (a) steaming the comminuted cellulosic fiber material, degassing it, and simultaneously heating the cellulosic material; Slurrying the comminuted cellulosic fibrous material with a cooking liquor to produce a slurry of the liquid and the cellulosic material; and (c) pressurizing the slurry at a location at least 30 feet below the top of the treatment vessel; Transferring the material to the top of the processing vessel, wherein the step of increasing the pressure comprises performing the step on the slurry using two or more high pressure slurry pumps. 17. A method for supplying a comminuted cellulosic fiber material to the top of a treatment tank, comprising the steps of: (a) steam-treating the cellulosic material, degassing the same, and simultaneously heating the cellulosic material; Slurrying with a cooking liquor to produce a slurry of the liquor and the cellulosic material; (c) pressurizing the slurry at a location at least 30 feet below the top of the processing tank, and placing the pressurized cellulose material on top of the processing tank. Transferring, wherein the step of raising the pressure comprises performing the step on the slurry using one or more high-pressure slurry pumps; and (d) at startup, between the pump outlet and the inlet. Establishing a circulating loop. 18. The method according to claim 17, wherein a first valve is provided in the circulation loop and a second valve is provided between the pump outlet and the treatment tank; step (d) comprises the steps of: Opening and closing the second valve at least partially; (e) closing the first valve after startup,
The method further comprising causing the second valve to open. 19. The method of claim 17, wherein
(E) returning the liquid from the processing tank to the pump inlet;
(F) the method further comprising the step of ensuring that the retentate is cooled and has a temperature below the point at which it flashes during handling. 20. The method according to claim 17, further comprising a second treatment tank; (e) statically diverting the liquid flow from the last outlet of the pump and directing each part of the flow to each treatment tank. The method further comprising the step of inducing. 21. The method according to claim 16, wherein a circulation loop is established between each pump outlet and inlet during start-up. 22. The method according to claim 21, wherein a first valve is provided in each circulation loop, and a second valve is provided between each pump outlet and each processing tank; Opening each first valve and at least partially closing each second valve; and (e) further comprising, after startup, closing each first valve and opening each second valve. Features method. 23. The method of claim 16, wherein
(E) returning the liquid from the processing tank to the pump inlet;
(F) further comprising the step of ensuring that the retentate is cooled and has a temperature below the point at which it flashes during handling.