JPH10216735A - Method and apparatus for pretreatment of amine-containing waste solution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple and continuous pretreatment method easy in the handling of a filter, the treatment of floc or the cleaning of a contaminated filter, much in treatment quantity and not generating the clogging caused by filtering in pretreatment removing a bacteria prohibiting substance in biological treatment for an, amine- containing waste soln. such as a waste soln. of a water-soluble cutting oil agent or secondary treated water thereof and a small-sized apparatus therefor. SOLUTION: A flocculant 7 and a pH adjusting agent 6 are charged in a chemical treatment tank 4 to insolubillze or flocculate a bacteria prohibiting substance and a waste soln. containing the insolubilized or flocculated bacteria prohibiting substance is supplied to a ceramic filter 10 to be separated into a filtrate and a conc. soln. and the filtrate is supplied to biological treatment of a next process from a discharge port 12 while the conc. soln. is again chemically treated to insolubilize or flocculate the bacteria prohibiting substance to be again supplied to the ceramic filter 10 to be separated into a filtrate and a conc. soln. This operation is repeated. Further, a flock separation tank 16 is disposed between an accumulator 13 for backwashing and a circulating passage 16a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a biological treatment for treating an amine-containing waste liquid, particularly a water-soluble cutting fluid or a water-soluble cleaning liquid used in a metalworking process, in a mineral oil, a fatty acid, a surfactant and the like contained in the waste liquid. The present invention relates to a pretreatment method for biological treatment for efficiently removing biological substances such as chemicals and solid sludge and removing biological substances, and an apparatus therefor.

[0002]

2. Description of the Related Art As for the treatment of waste liquid containing amines discharged from factories and the like, biological treatment for treating waste liquid containing amines using microorganisms that decompose amines into ammonia is known (for example, JP-A-7-303894). However, in order to carry out biological treatment using microorganisms that decompose amines into ammonia, substances that inhibit microorganisms in the waste liquid, such as mineral oil, fatty acids, surfactants, solid sludge, etc., also consist of these. It is necessary to sufficiently remove preservatives, rust inhibitors and the like.

[0003] That is, if a microorganism is brought into contact with a waste liquid in which the removal of these inhibitors is not sufficiently removed to perform desired purification, a long processing time is required, and a processing apparatus becomes large, and the processing becomes stable. do not do. However, JP-A-7-30389
In JP-A No. 4 (KOKAI) No. 4, no such removal method is disclosed.

On the other hand, in Japanese Unexamined Patent Publication No. Hei 7-963, a coagulant or a pH adjuster is added to a waste liquid into a separation tank and dissolved in the waste liquid, not before the biological treatment step, but in a step before the activated carbon adsorption treatment. There is disclosed a method in which a waste liquid is sucked through a membrane filter after aggregating treatment of a microorganism inhibitory substance, and the waste liquid is filtered and separated into aggregates and permeated water. However, in this case, since a film is used, there is a problem that removal of contamination on the film surface, the film surface of the polymer compound is not suitable for oil, and scratches due to mixing of sludge are liable to occur.

[0005]

On the other hand, Japanese Patent Application Laid-open No. Sho 63-2
Japanese Patent No. 94915 discloses that water and oil are separated by passing oil-containing wastewater through a ceramic filter. Therefore, it is conceivable to use a ceramic filter instead of the membrane filter disclosed in Japanese Patent Application Laid-Open No. 7-963. However, in Japanese Patent Application Laid-Open No. 63-294915, water and oil are separated by a ceramic filter. However, separation of substances such as fatty acids, surfactants, and solid sludge other than the oil component in the above-described inhibitory substances is not described. It is not disclosed and its effect is not clear.

Further, when the ceramic filter is put in the separation tank, there is a problem that handling becomes difficult and the apparatus becomes large. Further, there is still a problem that the treatment of the aggregates and the cleaning of the contamination filter are troublesome, and the transmission area must be increased in order to increase the processing amount.

An object of the present invention is to provide a biological treatment pretreatment device for removing a microorganism inhibitory substance dissolved in a waste liquid, in which the treatment tank is small and the filter is easy to handle.
Further, it is an object of the present invention to provide a pretreatment method and an apparatus for treating an amine-containing waste liquid, in which the treatment of aggregates and the cleaning of a contaminated filter are easy and the treatment amount is large. Furthermore, clogging due to filtration of the pretreatment device is prevented, and by performing simple and continuous pretreatment, the biological treatment of the next step can be stably continued, and the biological treatment tank is prevented from being enlarged. That is the task.

[0008]

Means for Solving the Problems In order to solve the above problems, in the present invention, in a biological treatment pretreatment step of treating waste liquid containing amines and the like using a microorganism that decomposes amines into ammonia, Add a flocculant to wastewater containing oil, fatty acid, surfactant, solid sludge, etc., which is a substance that inhibits microorganisms in biological treatment dissolved in wastewater in a chemical treatment tank with a flocculant and pH adjustment function Alternatively, a chemical treatment is performed while adjusting the pH, and the emulsified oils, fatty acids, surfactants, etc. other than solids such as sludge are insolubilized and aggregated in water. This waste liquid is supplied to a ceramic filter in a fixed amount, and is separated into a filtrate and a concentrated liquid.
The filtrate passed through the pores of the filter is led to the filtrate tank, and the remainder of the waste liquid that has not passed through the filter is returned to the chemical treatment tank as a concentrate. The returned concentrate is chemically treated again in the chemical treatment tank, circulated from the chemical treatment tank to the ceramic filter, and further filtered and concentrated. On the other hand, the filtrate from which the microorganism inhibitory substance has been removed is sequentially stored in a filtrate tank. The stored filtrate is further supplied to the next biological treatment tank. In the biological treatment tank, the waste liquid from which the microorganism inhibitor has been removed is treated, so that stable biological treatment can be continuously performed.

[0009] In the process of filtration of the ceramic filter, deposits are attached to the surface of the pores of the filter, and the ceramic filter is clogged. It is not efficient to stop the process every time to remove clogging, remove the filter, and backwash. Therefore, in claim 2,
Without removing the ceramic filter, the filtrate filtered by the ceramic filter was back-flushed for a certain period of time to backwash the ceramic filter.

Further, the backwashing is repeatedly performed, and the deposits peeled off from the filter surface at that time are returned to the chemical treatment tank. However, when they are circulated from the chemical treatment tank to the ceramic filter, they may adhere again to the filter surface. Therefore, in order to prevent re-adhesion, the concentrated solution of the ceramic filter is sedimented and separated again as floc that has been coagulated and settled before insolubilizing or coagulating the microbial inhibitor by chemical treatment, as in claim 3. Good.

In order to obtain the above-mentioned pretreatment method for treating an amine-containing waste liquid, in the present invention, the treatment of a water-soluble waste liquid containing amines and the like is carried out by using a microorganism which decomposes amines into ammonia. In a pretreatment device that excludes substances that inhibit the microorganisms such as mineral oil, fatty acids, surfactants, and solid sludge in a waste liquid supplied to the biological treatment to be performed, a coagulant or a pH adjuster can be added, and the aqueous solution is removed. A chemical treatment tank that is made to insolubilize or coagulate the microbial inhibitor dissolved in the acidic waste liquid, and a circulation pump that can send out a waste liquid containing the insoluble or coagulated microbial inhibitor from the chemical treatment tank, A ceramic filter for separating the waste liquid sent out by the circulation pump into a filtrate and a concentrated liquid, and returning the concentrated liquid separated by the ceramic filter to the chemical treatment tank; And ring path and filtrate discharge passage for discharging the filtrate separated in the ceramic filter provided.

In such an apparatus, in order to backwash the ceramic filter, an accumulator capable of storing the filtrate is connected to the filtrate discharge path, and the accumulator is further supplied with a pressurized fluid through an on-off valve. It is preferable to be able to selectively connect either the supplied pressurized fluid supply path or the discharge path for further discharging the filtrate to the outside.

In order to prevent the replenishment of the concentrated liquid of the ceramic filter from adhering to the filter surface, a floc separating tank is preferably provided in the circulation path.

[0014]

Next, an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram of a pretreatment device for treating an amine-containing waste liquid used in the present invention. In FIG. 1, after a waste liquid pit 1 in which an amine-containing waste liquid is stored and cutting chips and polishing sludge can be separated by natural sedimentation, a supernatant of the waste liquid in the waste liquid pit is quantitatively supplied to an oil-water separation tank 3. A liquid pump 2 is provided. The oil / water separation tank 3 separates and removes oil components such as unemulsified machine oil. The waste liquid separated and removed in the oil / water separation tank 3 is led to the chemical treatment tank 4.

A stirrer 5 is provided in the chemical treatment tank 4 to measure pH uniformity. For example, in the case of acid treatment, the pH in the chemical treatment tank 4 is set so that the acid can be automatically adjusted by the pump 6 and the controller 8. Further, the chemical treatment tank 4 is provided with a pump 7 capable of metering the coagulation accelerator into the chemical treatment tank. pH
In addition to the adjustment, the stirrer 5 can stir to promote the reaction of the aggregation promoter. If acid or alkali treatment is sufficient depending on the type of waste liquid, the addition of the coagulant may be omitted.

A circulation pump 9 is provided at an outlet of the chemical treatment tank 4 so as to send waste liquid to a ceramic filter 10. An inlet 11 is provided at one end of the ceramic filter 10, and the waste liquid subjected to the chemical treatment is introduced from the inlet 11 into the ceramic porous filter in the ceramic filter 10. The pore diameter of the pores in the innermost layer of the filter is 0.2 μm or less, preferably in the range of 0.05 to 0.2 μm. A part of the waste liquid is filtered through the filter from the inside of the filter, and the filtered waste liquid is discharged from the filtrate discharge port 12 to the filtrate discharge passage 12a. The remaining waste liquid that is not filtered by the filter is concentrated by discharging the filtrate to form a ceramic filter 10.
Is returned to the chemical treatment tank 4 from the concentrated liquid discharge port 15 at the other end through the circulation path 16a, the floc separation tank 16, and the circulation path 16b.

The filtrate discharge passage 12a is further connected to an accumulator 13 for storing the filtrate. The accumulator is provided with solenoid valves 17 and 18 which are on-off valves,
It is connected via an electromagnetic valve 17 to a discharge path 17a for further discharging the filtrate to the outside, and via an electromagnetic valve 18 to a pressurized fluid supply path 18a for supplying pressurized fluid. The solenoid valves 17, 18 are not simultaneously opened, and the accumulator can be selectively connected to the discharge passage 17a or the pressurized fluid supply passage 18a. Discharge path 17a
Is further connected to a filtrate tank 14.

The solenoid valve 17 on the discharge passage 17a side of the accumulator 13 is closed, and the pressurized fluid supply passage 18 of the accumulator 13 is closed.
When the electromagnetic valve 18a is opened, the pressurized fluid in the pressurized fluid supply path, for example, compressed air passes through the accumulator,
Together with the filtrate stored in the accumulator, the film containing the oil component, which is ejected from the outside of the filter toward the inside pores from the filtrate outlet 12 from the filtrate outlet 12, is peeled off, and the peeled-off film is removed. Is discharged from the concentrated liquid discharge port 15. That is, the filter can be backwashed using compressed air (pressurized fluid).

Next, the steps of the embodiment of the present invention will be described in detail. The values are not necessarily the same when the apparatus and the biological treatment method are different. In the pretreatment method of the waste liquid treatment of the present invention, among the microbial inhibitors in the waste liquid, first, a preparatory step for separating and removing solid sludge and non-emulsified oil components that are easily separated, After the chemical treatment of the dissolved emulsified oils, fatty acids, surfactants, etc., the process comprises microfiltration while circulating through a ceramic filter.

First, a waste liquid containing amines discharged from a factory or the like is stored in the waste liquid pit 1 for one day or more, and solids such as cutting chips and polishing sludge are naturally settled. The waste liquid separated by natural settling is quantitatively supplied to the oil / water separation tank 3 by the pump 2 at a rate of 10 to 50 L / min, and the oil / water separation tank 3 separates oil such as unemulsified machine oil. The preparation stage of the process is completed.

The waste liquid from which solid sludge which is insoluble in water and is easily separated or mineral oil which has not been emulsified is separated is introduced into the chemical treatment tank 4. The amine-containing waste liquid contains an emulsified mineral oil, a fatty acid, a surfactant, and the like dissolved in water, and is treated with an acid at pH 2 to 4, an alkali treatment at pH 10 to 13, or a mixture of acid and alkali. When the step treatment is performed, the substance dissolved in water becomes insoluble in water and is easily separated. Acid treatment, or alkali treatment, or acid, depending on the characteristics of the substance dissolved in the waste liquid
You can choose any of the two-stage alkali treatments.

When acid treatment is performed in the chemical treatment tank 4, stirring is performed by a stirrer 7 while adding dilute sulfuric acid by a pump 6 (50 times).
１００100 rpm), the pH is detected by the controller 8, and the
Adjust to a target value in the range of ~ 5. When the pH reaches the target value, the pump 6 is stopped, but the stirrer 7 is further stirred for 30 to 60 minutes and stopped. In the case of the alkali treatment, the pH is adjusted to a target value within the range of pH 10 to 13 while the alkali is added by the pump 6, and the stirrer is similarly operated. In the case of the two-stage treatment, an acid or alkali treatment step is first performed, and the ceramic filter 10 is circulated from the chemical treatment tank 4,
Next, an alkali or acid treatment step is performed in the chemical treatment tank 4.

In the chemical treatment tank 4, a 10% dodecanedicarboxylic acid (DD-acid) solution of the coagulation accelerator is added to the waste liquid by 1 to 3%.
Is added by a pump 7 and mixed with a waste liquid, and then a chemical treatment is performed.
The substance insolubilized by the chemical treatment aggregates and the particles become large, so that the film adhered to the inside of the ceramic filter 10 becomes coarse, and the filtration speed of the ceramic filter 10 can be maintained. DD- depending on the type of waste liquid
Terephthalic acid or activated clay may be added in place of the acid, and the addition of the coagulation promoter may be omitted if the effect of the addition of the coagulation promoter is small.

The waste liquid chemically treated in the chemical treatment tank 4 is guided to a ceramic filter 10 by a circulation pump 9. The circulation pump 9 has a flow rate in the pipe of 2 to 6 m / sec, preferably 3 to 4 m / sec, and a filter inlet pressure of 1 to 5 k.
g / cm ² , preferably 2-3 kg / cm ² . At this time, the filtration flow rate of the waste liquid discharged from the filtrate discharge port 12 is 2 to 6 Lit / min, and if the filtration rate is reduced below this range, the filter is clogged. In order to prevent clogging, the number of backwashing described later is adjusted.

The waste liquid supplied to the ceramic filter 10 is introduced into the filter from the inlet 11 and a part of the waste liquid passes through the pores inside the filter to the outside of the filter while separating and filtering substances insolubilized by the chemical treatment. The liquid is discharged from the filtrate outlet 12 to the filtrate tank 14 through the discharge path 12a, the accumulator 13, the solenoid valve 19, and the discharge path 19a. The solenoid valve 18 is closed. The remaining waste liquid concentrates the substance insolubilized by the chemical treatment, and is returned to the chemical treatment tank 4 from the concentrated liquid discharge port 15 through the circulation path 16a, the floc separation tank 16, and the circulation path 16b. The returned waste liquid is further chemically treated, and the circulation of the ceramic filter 10 from the chemical treatment tank 4 by the circulation pump 9 is repeated, so that the concentrated waste liquid is reduced to 1/5 to 1/20 of the waste liquid amount before circulation. Weight loss.

Normally, the solenoid valve 17 is open and the solenoid valve 18 is closed. However, in order to prevent the ceramic filter 10 from being clogged, for example, the filtration flow rate of waste liquid is monitored.
When the flow rate is below a certain amount, a backwash instruction is output,
The electromagnetic valve 17 is closed and the electromagnetic valve 18 is opened for 0.5 to 1 second. During this time, compressed air having a pressure of 3 to 5 kg / cm ² passes from the solenoid valve 18 through the accumulator 13 to push out the filtrate stored in the accumulator 13, and the compressed air and the filtrate are discharged from the ceramic filter 10. Backflow is carried out from the outlet 13 and spouted from the outside of the ceramic filter to the inside pores to perform backwashing. The membrane adhering to the inner surface of the filter is peeled off by the ejected filtrate and compressed air, and is discharged from the ceramic filter 10 through the concentrate discharge port 15. Thereafter, the solenoid valve 17 returns to the normal state of opening and the solenoid valve 18 closes.
After 0 minute, the same back washing operation is repeated to prevent clogging of the filter.

The membrane containing oil separated from the inside of the filter by backwashing or the like is formed into a floc shape, discharged from the concentrated liquid discharge port 15 of the ceramic filter 10, and sedimented and separated from the waste liquid in the floc separation tank 16. The separated flocs are accumulated in the floc separating tank 16 while the ceramic filter 10 is operating for filtration (several to several tens of hours), and are not released to the outside. Further, the waste liquid overflows the floc separation tank 16 and is returned to the chemical treatment tank 4.

The returned waste liquid is further chemically treated and repeatedly circulated from the chemical treatment tank 4 through the circulation pump 9 to the ceramic filter 10, and the filtrate of the waste liquid is stored in the filtrate tank 14 while removing microorganism-inhibiting substances. To go. The waste liquid in the chemical treatment tank 4 is reduced while being concentrated, and at the same time, the filtered waste liquid is increased to the filtrate tank 14, and if the amount of filtered waste liquid necessary for the next biological treatment can be secured, the circulation pump 9 is stopped. Then, a supply pump (not shown) is operated to guide the waste liquid in the filtrate tank 14 to a biological treatment tank (not shown).
When the waste liquid is separated and removed from the microorganism-inhibiting substance and stored in the filtrate tank 14 in this manner, the waste liquid is supplied to the biological treatment tank in the next step to almost completely decompose and remove amines.

[0029]

Next, an embodiment of the present invention will be described. The effects were compared by pretreating the present invention and the comparative example, respectively, and further performing biological treatment in the next step. In this experiment, first, in the comparative example, a cloth membrane filter having a filtration area of 4 was used in place of the ceramic filter 10 in order to remove more microbial inhibitors, and the membrane filter was subjected to an acid treatment in the chemical treatment tank 4 to remove the microorganism filter. Filtration was repeated and alkali treatment was performed again in the chemical treatment tank, that is, two-stage treatment. After that, the waste liquid was filtered through a membrane filter, and the filtrate was sent to the filtrate tank 14. Note that the membrane filter had a filtration area of 4 m ² , an inlet pressure of 1.5 kg / cm ² , and a pore diameter of 25 μm from the viewpoint of strength and production.

In the first embodiment of the present invention (Invention 1), artificial waste liquid corresponding to JIS-W1 is coagulated, and in the second embodiment of the present invention (Invention 2), JIS-W2 is used. An acid treatment is performed without adding an agent, and a filtration area of 0.
Filtration was performed by circulating the chemical treatment tank and the ceramic filter using a 7 m ² ceramic filter.
In the third embodiment of the present invention (Invention 3), J
DD-acid 1 which is a coagulation accelerator in waste liquid equivalent to IS-W1
After adding 0% solution to 2% of the amount of waste liquid, acid treatment was performed, and filtration treatment was similarly performed by circulating through a chemical treatment tank and a ceramic filter.

The amine-containing waste liquid used in this experiment was JIS
-W1 class equivalent and JIS-W2 class equivalent water-soluble cutting fluid stock solutions are each diluted about 30 times with tap water.
The pretreatments were compared in terms of the amount of waste liquid, that is, the filtration time required until the filtrate became 0.6 m ^3, and the state of the filtrate. Other conditions in the pretreatment step are the same as described above.

Further, in order to examine the influence of the biological treatment in the next step, the artificial waste liquid pretreated in Comparative Example and the present inventions 1 and ^{3 was} introduced into the biological treatment tank of the next step in an amount of 0.6 m ³ and then subjected to biological treatment. The change in amine concentration during the measurement and the processing time (days) until the amine concentration became zero were measured.

The microorganism used in the biological treatment tank, that is, the microorganism used as the inoculum is Corynebacterium N3 described in Japanese Patent Application No. 7-157448 filed separately by the present inventors.
FERMP-
A strain equivalent to the strain deposited as No. 15180 was used.

The biological treatment apparatus used was the biological treatment apparatus described in Japanese Patent Application No. 8-318489, which was separately filed by the present inventors. This equipment sends waste liquid pretreated in batches to an adjustment tank, adjusts the pH and the like in the adjustment tank, and converts the adjusted waste liquid to a carrier in which microorganisms that decompose and use amines are immobilized in a high concentration state. Into the biological treatment tank provided with
While aerating the air, the microorganisms are brought into contact with the waste liquid to decompose the amines, the waste liquid is returned from the biological treatment tank to the adjustment tank, and the waste liquid is sent again from the adjustment tank to the biological treatment tank, and the pH is adjusted and decomposed. The waste liquid is circulated to decompose and purify amines. The adjustment tank had a capacity of 0.7 m ³ , a contact temperature of 20 to 35 ° C., and a pH value in the adjustment tank near neutral (pH 7). This device was used to evaluate the effect of the pretreatment in a short time since the decomposition was performed quickly and reliably and stable biological treatment was possible.

Table 1 shows pretreatment conditions and results of the present inventions 1, 2, and 3 and a conventional example. Table 2 shows the biological treatment conditions and results of the present inventions 1 and 3 and the conventional example in the biological treatment after the pretreatment. The initial amine concentration described in Table 2 is a value obtained by detecting ethanolamine in amines. Also,
FIG. 2 shows the change of the amine concentration with respect to the number of days of the present invention, FIG. 3 shows the present invention 2, and FIG. The vertical axis represents the concentration of amine, and the horizontal axis represents the number of elapsed days.

[0036]

[Table 1]

[0037]

[Table 2]

First, in the comparative example, as shown in Table 1, a two-stage treatment with an acid and an alkali was performed to remove more of the microbial inhibitors, but clogging occurred once in each treatment process. Therefore, the membrane filter was replaced twice. Also, it takes about 48 hours (2 hours) including filtration time of the membrane filter to filter 0.6 m ³ of the chemically treated waste liquid.
Days). Also, the state of the filtrate is cloudy,
Inhibitors are not completely removed. Further, as a result of the biological treatment of the waste liquid subjected to the pretreatment of the comparative example in the next step, as shown in Table 2 and FIG. 4, it took about 2.1 days until the triethanolamine in the waste liquid was completely decomposed. Also,
As shown in FIG. 4, the amine concentration decreases at the initial stage, but decreases slowly thereafter.

Next, in the present invention 1, as shown in Table 1, the chemical treatment and the filtration treatment time of the waste liquid corresponding to JIS-W2 were 4 hours, and the treatment capacity was improved as compared with the comparative example. The state of the filtrate was clear, and the inhibitor was sufficiently removed. In the subsequent biological treatment, as shown in Table 2 and FIG. 2, the decomposition time of triethanolamine in the waste liquid was about 1.
As shown in FIG. 2, the decrease in amine concentration after the initial decrease decreased relatively linearly, indicating that the inhibitor was sufficiently removed compared to the comparative example.

On the other hand, in the present invention 2 using waste liquid equivalent to JIS-W1 type, the chemical treatment and filtration processing time was 7 hours, and the filtration speed was lower than that of waste liquid equivalent to W-2 type.
Filtration time was long. This is because the waste liquid equivalent to the W1 type has a larger content of mineral oil and surfactant than the waste liquid equivalent to the W2 type, so that the amount of flocs generated after the chemical treatment is larger and the viscosity is higher.

Therefore, in the present invention 3 in which the coagulation accelerator was added to the waste liquid equivalent to JIS-W1 class, the chemical treatment and the filtration treatment time were 5 hours, indicating that the function of the coagulation accelerator was large. In the subsequent biological treatment, as shown in Table 2 and FIG. 3, the decomposition time of triethanolamine in the waste liquid was about 1.7 days. As shown in FIG. , It can be seen that the microorganism inhibitory substances were efficiently removed by the pretreatment.

[0042]

As described above, according to the present invention, according to the present invention, the microorganisms in the waste liquid are chemically treated with the inhibitory substance while adding a coagulant or adjusting the pH, so as to insolubilize and coagulate in water, and the waste liquid is treated with a ceramic. A fixed amount is supplied to the filter, separated into a filtrate and a concentrate, and the remainder of the waste liquid that cannot pass through the filter is returned to the chemical treatment tank as a concentrate, subjected to chemical treatment again in the chemical treatment tank, and filtration and concentration are repeated. As a result, the present invention provides a pretreatment method and apparatus for treating amine-containing waste liquid, which does not require a large filtration area, has a small treatment tank, is easy to handle, and has a large treatment amount. .

Further, an accumulator is provided between the ceramic filter and the discharge passage, and the pressurized fluid is supplied to the accumulator to back-flow the filtrate without removing the ceramic filter, thereby backwashing the ceramic filter. Cleaning of the contamination filter was easy, clogging due to filtration of the pretreatment device was prevented, and simple and continuous pretreatment became possible.

Further, since a floc separating tank is provided in the circulation path, re-adhesion of the concentrated liquid of the ceramic filter to the filter surface is prevented, and the condensed portion of the concentrated liquid is easily separated into flocs to be collected, which is more efficient. Filtration and continuous pretreatment were made possible. Furthermore, since waste liquid with a small amount of biological inhibitors can be supplied to the biological treatment tank, the biological treatment in the next step can be stably continued, the treatment speed can be improved, and the biological treatment tank can be prevented from being enlarged. It became.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of the apparatus of the present invention.

FIG. 2 is a diagram showing a change in amine concentration with respect to the number of days elapsed in biological treatment of an amine-containing waste liquid pretreated in the first embodiment of the present invention.

FIG. 3 is a diagram showing a change in amine concentration with respect to the number of days elapsed in biological treatment of an amine-containing waste liquid pretreated in a third embodiment of the present invention.

FIG. 4 is a diagram showing a change in amine concentration with respect to the number of days of biological treatment of an amine-containing waste liquid pretreated in a conventional comparative example.

[Explanation of symbols]

 4 Chemical treatment tank 9 Circulation pump 10 Ceramic filter 12 Filtrate discharge port 12a Filtrate discharge path 13 Accumulator 14 Filtrate tank 15 Concentrate discharge port 16 Flock separation tank 16a, 16b Circulation path 17, 18 Solenoid valve (open / close valve) 17a Discharge path 18a Pressurized fluid path

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 9/00 502 C02F 9/00 502P (72) Inventor Katsuyuki Kawakami 1-1-1 Fujikoshi Honcho, Toyama City, Toyama Prefecture ) Inventor Naoshi Okawa 1-1, Oike-cho, Kosai-cho, Koga-gun, Shiga Prefecture Inside Neos Central Research Institute, Inc. (72) Inventor Takashi Yoneshima 1-1, Oikecho, Kosai-cho, Koga-gun, Shiga Prefecture Inside Neos Central Research Institute, Inc.

Claims (6)

[Claims] 1. A method for treating a water-soluble waste liquid containing amines or the like using a microorganism that decomposes amines into ammonia, such as a mineral oil, a fatty acid, a surfactant, a solid sludge, etc. in a waste liquid supplied to a biological treatment. In the pretreatment step for excluding the substance that inhibits the microorganism, a flocculant or a pH adjuster is added to insolubilize or aggregate the microorganism inhibitory substance dissolved in the aqueous waste liquid, and the solid sludge or the insolubilization or aggregation is performed. The waste solution containing the microorganism inhibitor is supplied to a ceramic filter, separated into a filtrate and a concentrated solution, the filtrate is supplied to the biological treatment in the next step, and the concentrated solution is again subjected to the chemical treatment. Microbial inhibitors are insolubilized or aggregated and supplied again to the ceramic filter,
A pretreatment method for treating an amine-containing waste liquid, wherein separation of a filtrate and a concentrated liquid is repeatedly performed. 2. The ceramic filter according to claim 1, wherein the filtrate filtered by the ceramic filter is caused to flow backward for a predetermined time to backwash the ceramic filter.
A pretreatment method for treating an amine-containing waste liquid as described above. 3. The amines according to claim 1, wherein the concentrated solution of the ceramic filter is again separated as flocs before insolubilizing or aggregating the microorganism-inhibiting substance by the chemical treatment. Pretreatment method for waste liquid treatment. 4. Mineral oils, fatty acids, surfactants, solid sludge, etc. in a waste liquid supplied to a biological treatment for treating a water-soluble waste liquid containing amines or the like using a microorganism that decomposes amines into ammonia. In the pretreatment device for excluding the substance that inhibits the microorganism, a chemical treatment tank in which a coagulant or a pH adjuster can be added and the microbial inhibitor dissolved in the water-soluble waste liquid is insolubilized or aggregated. When,
A circulating pump capable of sending a waste liquid containing a microorganism inhibitor which has been insolubilized or aggregated from the chemical treatment tank, a ceramic filter for separating the waste liquid sent by the circulating pump into a filtrate and a concentrate, and a ceramic filter; A pretreatment device for amine-containing waste liquid treatment, comprising: a circulation path for returning the concentrated liquid to the chemical treatment tank; and a filtrate discharge path for discharging the filtrate separated by a ceramic filter. . 5. A pressurized fluid supply passage to which a pressurized fluid is supplied via an on-off valve, wherein an accumulator capable of storing the filtrate is connected to the filtrate discharge passage. 5. The pretreatment device for treating amines-containing waste liquid according to claim 4, wherein any one of a filter and a discharge path for further discharging the filtrate to the outside can be selectively connected. 6. The pretreatment apparatus for treating amine-containing waste liquid according to claim 4, wherein a floc separation tank is provided in the circulation path.