JP4294762B2 - Membrane treatment method and membrane treatment apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention separates sludge in a reaction tank for biological treatment, sludge transferred from the reaction tank or concentrated sludge thereof, human waste water before biological treatment, agglomerated reaction liquid by adding a flocculant or the reaction liquid in a precipitation tank. The present invention relates to a membrane treatment method and a membrane treatment apparatus for filtering a raw solution such as a concentrated sludge and a supernatant thereof.
[0002]
[Prior art]
Conventionally, as a membrane treatment method and a membrane treatment apparatus, a pressure-type membrane treatment method and a membrane treatment apparatus described in FIG. 4 of Japanese Patent Application No. 8-99445 are known (see FIG. 4). In FIG. 4, 10 is a membrane device, 11 is a reaction tank in which a stock solution such as sludge is stored, and 12 is a pressure pump. Reference numeral 13 denotes a frame plate that can be disassembled by removing a packing (not shown), and a plurality of film-coated plates 14 are detachably fixed in the frame plate 13. The membrane-attached plate 14 includes a membrane support member 17 and a flat membrane 18. The flat membrane 18 is fixed to both side surfaces of the membrane support member 17 via a gap 17 a, and liquid is provided above and below the membrane-attached plate 14. Openings 15 and 16 for forming a flow path are formed, 19 is a liquid drop discharge groove, 20 is a stock solution inlet provided in the frame plate, 21 is a concentrate outlet, and 22 is a stock solution or concentrate. Is an intermembrane flow path through which.
[0003]
In such a membrane treatment apparatus, the stock solution in the reaction tank 11 is introduced into the stock solution inlet 20 of the membrane device 10 by the operation of the pressure pump 12, enters the intermembrane flow path 22 through the opening 16, and permeates the flat membrane 18. The filtrate is separated into a concentrated liquid and a concentrated liquid. The liquid smoke is taken out through the liquid discharge groove 19, and the concentrated liquid is returned to the reaction tank 11 through the concentrated liquid outlet 21 and mixed with the stock solution in the reaction tank 11. The above-described circulation operation is repeatedly performed by the operation of the pressurizing pump 12.
[0004]
[Problems to be solved by the invention]
In such a pressure-type film processing method that performs film processing using the pressure pump 12, in order to suppress the growth of the gel layer and ensure the flow rate, the flow rate of the liquid in the intermembrane flow path 22 is set to 2 to 2. A technique of speeding up to about 2.5 m / sec is employed. For this reason, the pressurizing pump 12 needs to have a power that can transfer the stock solution in the reaction tank 11 to the membrane device 10 and can obtain the liquid flow rate in the intermembrane flow path 22. is there. Therefore, the pressurizing pump 12 used for carrying out this conventional pressurizing type membrane treatment method is required to have a high lift and a high horsepower, and an increase in power cost is unavoidable. The pressurizing pump 12 with high head and high horsepower is inevitably enlarged, and there is a problem that it is necessary to secure a wide installation space.
[0005]
On the other hand, in recent years, there has been a demand to cope with the increase in the processing amount by unitizing a membrane apparatus for taking out the liquid smoke from the stock solution and increasing the number of units.
[0006]
In the conventional pressure type membrane treatment apparatus described above, the supply and supply of the stock solution from the reaction tank 11 to the membrane apparatus 10 and the creation of the predetermined liquid flow velocity in the intermembrane flow path 22 of the membrane apparatus 10 are pressurized. Since it depends only on the pump 12, it is possible to transfer and supply the stock solution to the plurality of membrane devices 10 only by the operation of one pressure pump 12 and to produce the predetermined liquid flow rate in each membrane device 10. In reality, this is impossible. Therefore, in order to meet such a demand, a set of membrane processing apparatuses is constituted by the membrane apparatus 10 and the pressurizing pump 12 that pressurizes and supplies the stock solution in the reaction tank 11 into the membrane apparatus 10, It is conceivable to increase the number of pairs of the membrane device 10 and the pressure pump 12 in accordance with the target processing amount.
[0007]
However, since the number of pressure pumps 12 is increased according to the number of sets to be processed, not only the equipment cost is excessive, but also the space for installing the pressure pump 12 is increased. There is also a new problem in the installation space that an increased number of sets are required.
[0008]
In general, the circulation flow rate of the liquid in the intermembrane flow path 22 is determined by the flow velocity of the liquid flowing in the intermembrane flow path 22. This flow rate is also regulated by the diameters of the openings 15 and 16 formed above and below the membrane-coated plate 14. The diameters of the openings 15 and 16 ensure a large circulating flow rate in order to obtain a desired permeated liquid amount. For the purpose, it is formed to be relatively large (for example, 65 mmφ per opening). To meet this requirement, in the conventional pressure-type membrane treatment apparatus, the reaction tank 11 returns to the reaction tank 11 via the intermembrane flow path 22. Piping for constituting the route and various accessories provided in the piping are also large. Therefore, when the number of pairs of the membrane device 10 and the pressure pump 12 is increased, the equipment cost required for the accessories is inevitably increased, and there is a problem that the cost is significantly increased as a whole.
[0009]
The present invention has been made in view of the problems of the prior art, and can reduce the cost in terms of equipment and power, can save space, and can be used in the conventional manner. It is an object of the present invention to provide a film processing method capable of obtaining a processing amount similar to that of the pressure mold.
[0010]
Another object is to provide a film processing apparatus that can save cost and space even if the number of film apparatuses is increased to cope with an increase in throughput.
[0011]
[Means for Solving the Problems]
A membrane processing apparatus according to the present invention that solves the above-described problems is a membrane apparatus in which a plurality of filtration membranes are arranged in parallel to extract the filtrate from a stock solution in an intermembrane flow path formed between the filtration membranes. A circulation tank having a concentrate discharge section for supplying an undiluted solution from a reaction tank by a concentrate pump and returning an overflow liquid to the reaction tank, and a circulation pump between the circulation tank and the membrane device A circulation system for circulating the liquid by the operation of the circulation pump is formed to constitute a membrane treatment unit, and the circulation system of each membrane treatment unit includes an introduction pipe for introducing the stock solution from the circulation tank to the membrane device, The membrane processing unit is constituted by an intermembrane flow path in the membrane device and a return pipe for returning the concentrated liquid in the membrane device to the circulation tank, and a circulation pump is arranged in the line of the introduction pipe. A plurality of units One stock pump for supplying stock to the circulation tank unit provided, and wherein the retrieving the filtrate said stock solution in the circulation tank was circulated and supplied to each present in each membrane treatment units by the pressure of the circulating pump .
[0015]
According to this, it is possible to easily cope with an increase in the amount of processing by increasing the number of film processing units having a film apparatus that performs film processing. Moreover, even if the number of membrane devices is increased in this way, the liquid flow rate in the inter-membrane flow path of the membrane device is produced by the operation of a circulation pump interposed in the circulation system formed between the circulation tanks. Therefore, it does not depend on the stock solution pump that feeds the stock solution from the reaction tank. In other words, the stock solution pump only needs to perform only the stock solution transfer, and therefore, the single stock pump can be sufficiently covered without increasing the size regardless of the number of membrane processing units. Therefore, even if the number of membrane processing units is increased in order to cope with the increase in the processing amount, only one undiluted liquid pump is required as in the conventional case, and the equipment cost does not increase excessively compared with the conventional one. The installation space for the stock solution pump will not increase.
[0016]
In addition, since the piping between one undiluted solution pump and the circulation tank of each membrane processing unit can be made common to each membrane processing unit, the equipment cost required for accessories provided in this piping has also been conventionally increased. It does not increase.
[0017]
Therefore, it is possible to achieve cost saving and space saving while the film processing apparatus can increase the processing amount.
[0018]
Furthermore, according to the present invention, since one stock solution pump is common to each membrane processing unit, this one stock solution pump is stopped, and a cleaning solution is poured into each circulation tank, so that each membrane treatment unit Automatic washing with water is also possible.
[0020]
The circulation pump is preferably a line pump, and can contribute to low power and cost reduction.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, as the raw solution, for example, sludge in a biological treatment tank, sludge transferred from the reaction tank or concentrated sludge thereof, human waste before biological treatment, agglutination reaction liquid by adding a flocculant or reaction liquid thereof Concentrated sludge separated by a sedimentation tank and its supernatant. The present invention can also be applied to reuse of wastewater, recovery of valuable materials, use of rainwater, various separation and concentration, various separation and concentration purification, and the like. Therefore, various stock solutions are included in the stock solution of the present invention as long as the object is achieved.
[0022]
The filter membrane used in the present invention is not particularly limited as long as the stock solution can be filtered at a relatively low pressure, and may be any of an ultrafiltration membrane, a precision filtration membrane, and the like. As the form of the film, a flat film is preferable.
[0023]
Embodiments of a film processing method according to the present invention will be described below with reference to the drawings showing an example of a film processing apparatus suitable for carrying out this film processing method.
[0024]
FIG. 1 is a schematic configuration diagram showing an example of a film processing apparatus, and FIG. 2 is a cross-sectional view of a main part showing a film apparatus used in the film processing apparatus shown in FIG.
[0025]
In FIG. 1, 1 is a membrane device that separates a stock solution into a filtrate and a concentrated solution, and 2 is a circulation in which the stock solution is supplied to the membrane device 1 and the stock solution and the concentrated solution separated by the membrane device 1 are returned and stored. A tank 3 is a circulation pump that creates a circulation flow between the membrane device 1 and the circulation tank 2, 4 is a reaction tank in which the stock solution is stored, and 5 is for transferring the stock solution from the reaction tank 4 to the circulation tank 2. It is a stock solution pump.
[0026]
As shown in FIG. 2, the membrane device 1 forms a side frame that can be opened by frame plates 101 and 102 provided in a vertical direction at a predetermined interval. A partition plate 103 is provided in the vertical direction, and the frame plates 101 and 102 are partitioned into a plurality of blocks S1,.
[0027]
The partition plate 103 is formed with a liquid circulation port 104 in the upper part or the lower part, and adjacent blocks are connected to each other by the circulation port 104. The partition plate 103 may be configured such that the flow ports 104 are alternately arranged on the upper and lower sides of the adjacent partition plates 103 so that the liquid flow in the adjacent blocks is alternately formed upward and downward. preferable.
[0028]
In each block S of the membrane device 1 partitioned by the partition plate 103, a plurality of membrane-attached plates 105 are arranged in parallel in the vertical direction.
[0029]
The membrane-attached plate 105 includes a membrane support member 108 having openings 106 and 107 formed in the vicinity of upper and lower ends, and flat membranes (filter membranes) 109 fixed to both side surfaces thereof. Is fixed to the membrane support member 108 by seal rings 110 and 111 fitted in the upper and lower openings 106 and 107, respectively.
[0030]
The membrane support member 108 is formed of a plate material, and the surface thereof is formed in an uneven shape having a corrugated cross section. The flat membrane 109 forms a drainage portion 112 for the soot that has permeated through the flat membrane 109 while ensuring a slight gap between the flat membrane 109 and the membrane support member 108 on both sides of the membrane support member 108.
[0031]
Reference numeral 113 denotes a liquid discharge groove provided at the lower end of the membrane support member 108, which is connected to the liquid collection pipe 301 and configured to be able to take out the liquid through the liquid collection pipe 301. .
[0032]
Packing is performed along the outer edge of the film-coated plate 105 between the multiple film-coated plates 105, between the film-coated plate 105 and the frame plates 101, 102, and between the film-coated plate 105 and the partition plate 103. 114 is provided to prevent external leakage of the liquid. Therefore, the membrane device 1 is formed in a watertight manner by the frame plates 101 and 102 constituting the side frame and the packing 114.
[0033]
At the same time, the packing 114 has an intermembrane flow in which an undiluted solution or a concentrated solution flows between adjacent plates 105 with membranes, between the plate with membranes 105 and the frame plates 101 and 102, and between the plate with membranes 105 and the partition plate 103. A path 115 is formed. Therefore, the distance between the intermembrane flow paths 115 is regulated by the packing 114, and the distance between the intermembrane flow paths 115 can be adjusted by adjusting the thickness of the packing 114.
[0034]
The distance between the intermembrane flow paths 115 is preferably 1.5 mm or more, and more preferably 3.0 mm or more from the viewpoint of preventing the blockage of the flow paths. The upper limit is preferably 8.0 mm or less, and more preferably 6.0 mm or less, for the volume efficiency of the membrane device 1.
[0035]
Further, the packing 114 also functions to fix the outer edge of the flat membrane 109 on both side surfaces of the membrane support member 108 in the membrane-equipped plate 105.
[0036]
The number of blocks S in the membrane device 1 (number of partition plates 103 + 1) and the number of membrane-equipped plates 105 provided in each block S are various values such as flux, throughput, capacity of the circulation pump 3 to be described later. It is decided as appropriate considering the conditions.
[0037]
In the membrane device 1, an inlet 116 for introducing the stock solution into one frame plate 101 is formed, and an outlet 117 for discharging the concentrated solution is formed in the other frame plate 102, respectively. And the return pipe 202 is connected to the circulation tank 2.
[0038]
The circulation tank 2 has a predetermined height in the circulation tank 2 between the stock solution transferred and supplied from the reaction tank 4 storing the stock solution by the operation of the stock solution pump 5 and the concentrated solution discharged from the membrane device 1. In order to supply a new stock solution to the membrane device 1, the membrane device 1 is juxtaposed.
[0039]
This circulation tank 2 has a stock solution receiving portion 203 for receiving a stock solution supplied from the reaction tank 4 through the supply pipe 401 at the lower part, and further, a circulation tank from the outlet 117 of the membrane device 1 through the return pipe 202. 2 has a concentrated liquid discharge section 204 that overflows the concentrated liquid discharged into the reaction tank 4 and returns the concentrated liquid to the reaction tank 4 through the discharge pipe 402 above the connecting portion of the return pipe 202.
[0040]
The stock solution in the circulation tank 2 is introduced into the membrane device 1 from the inlet 116 of the membrane device 1 through the introduction pipe 201. The inlet 116 in the membrane device 1 is formed in the lower part of the frame plate 101, and the outlet 117 is formed in the upper part of the frame plate 102. The stock solution in the circulation tank 2 introduced from the inlet 116 is the In the membrane device 1, they flow through the inlet 116 of the membrane device 1, the intermembrane flow path 115 in each block S, the openings 106 and 107, and the circulation port 104, and alternately flow upward and downward in each block S. Thereafter, the liquid is returned again to the circulation tank 2 through the outlet 117 and the return pipe 202, thereby constituting a circulation channel (circulation system) in which the liquid circulates between the membrane device 1 and the circulation tank 2.
[0041]
A circulation pump 3 is interposed in the middle of the circulation flow path configured between the membrane device 1 and the circulation tank 2, and a predetermined flow velocity is created by the operation of the circulation pump 3, and liquid is placed in the circulation flow path. Is circulating. As shown in the drawing, the circulation pump 3 includes an introduction pipe 201 that introduces the stock solution from the circulation tank 2 to the membrane apparatus 1 among the introduction pipe 201 and the return pipe 202 that connect the membrane apparatus 1 and the circulation tank 2. It is preferable to interpose in the line.
[0042]
A line pump can be preferably used as the circulation pump 3. This can contribute to lower power and cost.
[0043]
The undiluted solution flowing through the intermembrane flow path 115 in the course of circulation passes through the flat membrane 109 and is filtered, and the filtered filtrate passes through the filtrate discharge unit 113 and the filtrate collecting pipe 301 to form a membrane device. 1 is taken out. On the other hand, when the filtrate is taken out from the stock solution, the concentration of the concentrated substance in the stock solution in the membrane device 1 increases, so that the stock solution in the reaction tank 4 transferred and supplied by the stock solution pump 5 is circulated to prevent the concentration from rising. The tank 2 is received from the stock solution receiving unit 203, and the excess stock solution or concentrate in the circulation tank 2 is overflowed from the concentrate discharge unit 204 and returned to the reaction tank 4, whereby the concentration of concentrated substances in the circulation system is increased. Is not abnormally high.
[0044]
In addition, the membrane can be easily cleaned by removing the stock solution from the circulation tank 2 and adding clean water, and circulating the clean water in the membrane device 1 by the circulation pump 3, and it is not necessary to prepare a special cleaning device. . If chemicals are introduced into the circulation tank 2, chemical cleaning can be easily performed.
[0045]
However, in the membrane treatment method according to the present invention, the liquid flow rate in the intermembrane flow path 115 is 2 to 2 by the circulation pump 3 interposed in the circulation system constituted between the membrane device 1 and the circulation tank 2. Driven to a pressure of about 3.0 m / sec (in consideration of pressure loss between the membranes), circulated and supplied to the circulation system, and in the process, the liquid from the undiluted solution in the intermembrane flow path 115 is supplied. Try to take it out.
[0046]
The circulation pump 3 is not affected at all by the drive of the stock solution pump 5 for transferring the stock solution in the reaction tank 4 to the circulation tank 2. That is, the liquid flow rate is generated by driving only the circulation pump 3 interposed in the circulation system, unlike the conventional membrane processing method in which the liquid flow rate is generated only by the pressure pump that feeds the stock solution from the reaction tank. . In other words, the stock solution pump 5 only needs to transfer the stock solution in the reaction tank 4 into the circulation tank 2, and is driven to create a flow rate of the fluid flowing through the intermembrane flow path 115 as in the prior art. There is no need.
[0047]
As a result, the stock solution pump 5 having a relatively low power that can transfer the stock solution in the reaction tank 4 into the circulation tank 2 without considering the liquid flow rate in the intermembrane flow path 115 may be used. As a result, the stock solution pump 5 can be reduced in size, so that the power cost can be reduced and the installation space can be reduced. On the other hand, the circulation pump 3 is also small in size and low in power because it is sufficient to circulate and supply the liquid at the liquid flow rate in the circulation system constituted between the circulation tank 2 and the membrane device 1. A power type can be used, and specifically, a low-power line pump can be used as described above. Moreover, since the liquid flow rate in the intermembrane flow path 115 in the membrane device 1 is almost the same as that of the conventional pressure-type membrane treatment method, the cost is reduced and the space is saved, but the same as the conventional one. It is possible to maintain the throughput.
[0048]
In particular, the present invention is very useful when the reaction tank 4 is buried underground and the stock solution is transferred from the underground buried reaction tank 4 to the circulation tank 2 by the stock solution pump 5.
[0049]
In the above-described embodiment, the case where a plate material having an uneven surface is used as the membrane support member 108. However, the present invention is not limited to this, and the membrane support member may be a plate material having a porous structure. The support member may be a synthetic fiber plate.
[0050]
In addition, a suction pump (not shown) may be additionally used as needed to take out the filtrate that passes through the flat membrane 109 from the stock solution flowing through the intermembrane flow path 115 and is filtered. Is optional.
[0051]
Next, an embodiment of the film processing apparatus according to the present invention will be described with reference to FIG.
[0052]
FIG. 3 is a schematic configuration diagram showing an example of a film processing apparatus according to the present invention.
[0053]
In the membrane processing apparatus shown in this embodiment, the same components as those of the membrane apparatus 1, the circulation tank 2 and the circulation pump 3, and the other membrane processing apparatus shown in FIG. Is omitted.
[0054]
In the membrane treatment apparatus shown in this embodiment, a membrane apparatus 1, a circulation tank 2, and a circulation flow path (circulation system) provided with a circulation pump 3 are combined into one membrane treatment unit U. It is composed. Thus, it becomes possible to easily cope with an increase in the processing amount by increasing the number of film processing units U having the film apparatus 1 that performs the film processing.
[0055]
In addition, in FIG. 3, although the case where this film processing unit U is provided with three units U1-U3 is shown, the number of the film processing units U is suitably determined according to a desired processing amount. It is not limited to the illustrated example.
[0056]
To the circulation tank 2 of each of the membrane processing units U1 to U3, the stock solution is transferred and supplied from one reaction tank 4 through the supply pipe 401 by only one stock solution pump 5 in common to each of the membrane processing units U1 to U3. I have to. In each of the membrane processing units U1 to U3, a circulation pump 3 is provided in a circulation system that circulates a liquid between the membrane device 1 and the circulation tank 2, and the membrane of the membrane device 1 is only operated by the circulation pump 3. Since a predetermined liquid flow rate is created in the flow path 115, the stock solution pump 5 only needs to transfer the stock solution in the reaction tank 4 into each circulation tank 2 and circulates in the intermembrane flow path 115. There is no need to drive to create a liquid flow rate. Therefore, it is possible to share the single undiluted solution pump 5 among the membrane processing units U1 to U3.
[0057]
That is, even if the number of membrane devices 1 is increased in this way, the liquid flow rate in the inter-membrane flow path 115 of the membrane device 1 is the circulation pump 3 interposed in the circulation system formed between the circulation tank 2. Therefore, the undiluted solution pump 5 only needs to perform the undiluted solution transfer operation. Therefore, the undiluted solution pump 5 is one unit without causing enlargement regardless of the increase in the number of membrane processing units U. I can cover enough. Therefore, even if the number of the membrane processing units U is increased in order to cope with the increase in the processing amount, only one undiluted solution pump 5 is required as in the conventional case, and the equipment cost is excessively increased as compared with the conventional case. In addition, the installation space for the stock solution pump 5 does not increase.
[0058]
Further, a pipe 401 for transferring the raw liquid from the reaction tank 4 to the circulation tank 2 of each membrane processing unit U1 to U3 by a single raw liquid pump 5 and a pipe 402 for returning the overflow liquid from the circulation tank 2 are also provided for each membrane processing unit. Since it can be made common to U1-U3, the installation cost required for the accessories interposed in these piping 401,402 does not increase excessively compared with the past.
[0059]
Therefore, it is possible to achieve cost saving and space saving while the film processing apparatus can increase the processing amount.
[0060]
Furthermore, since one undiluted solution pump 5 is shared by the respective membrane treatment units U1 to U3, each undiluted solution pump 5 is stopped and a cleaning solution is introduced into each circulation tank 2, whereby each of the membrane treatment units U1. It is also possible to easily perform automatic water washing of ~ U3.
[0061]
In each of the membrane processing units U1 to U3 in this membrane processing apparatus, as needed, a suction pump is used to take out the filtrate that passes through the flat membrane 109 and is filtered from the stock solution flowing through the intermembrane flow path 115. It is optional to additionally use (not shown).
[0062]
【The invention's effect】
According to the membrane processing method of the present invention, the cost in terms of equipment and power can be kept low, and space can be saved, and the processing amount is comparable to that of the conventional pressure type. Can be obtained.
[0063]
In addition, according to the film processing apparatus of the present invention, even if the number of film apparatuses is increased to cope with an increase in the processing amount, cost saving and space saving can be achieved.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a film processing apparatus for carrying out a film processing method of the present invention. FIG. 2 is a partially cutaway sectional view showing an embodiment of the film apparatus. FIG. 4 is a schematic cross-sectional view showing a conventional pressure-type membrane treatment apparatus.
DESCRIPTION OF SYMBOLS 1 Membrane apparatus 101,102 Frame board 103 Partition board 104 Flow port 105 Membrane board 106,107 Opening 108 Membrane support member 109 Flat membrane (filtration membrane)
110, 111 Seal ring 112 Liquid discharge part 113 Liquid discharge groove 114 Packing 115 Intermembrane flow path 116 Stock solution inlet 117 Stock solution outlet 2 Circulation tank 201 Introducing pipe 202 Return pipe 203 Stock solution receiving part 204 Concentrated liquid Discharge unit 3 Circulation pump 4 Reaction tank 401 Supply pipe 402 Discharge pipe 5 Stock solution pump S Block U Membrane treatment unit

Claims (2)

A stock solution is supplied from a reaction tank by a stock solution pump to a membrane device in which a plurality of filtration membranes are arranged in parallel to take out the filtrate from the stock solution in the intermembrane flow path formed between the filtration membranes , A circulation tank having a concentrate discharge part for returning the overflow liquid to the reaction tank is provided in parallel, and a circulation pump is interposed between the circulation tank and the membrane device to circulate the liquid by the operation of the circulation pump. A circulation system is formed to form a membrane treatment unit, and the circulation system of each membrane treatment unit includes an introduction pipe for introducing a stock solution from a circulation tank to the membrane device, an intermembrane flow path in the membrane device, and the membrane device. It is constituted by a return pipe that returns the concentrated liquid to the circulation tank, and a circulation pump is arranged in the line of the introduction pipe, and a plurality of the membrane treatment units are provided, and the circulation tank of each membrane treatment unit is provided in the circulation tank. One of the undiluted solutions The liquid pump is provided, membrane treatment apparatus characterized by taking out the filtrate of the stock solution of the circulation tank of each existing circulating supplied to the membrane treatment units by the pressure of the circulation pump. The film processing apparatus according to claim 1 , wherein the circulation pump is a line pump.

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