JPS61146397A - Method and apparatus for treating night soil - Google Patents

Abstract

PURPOSE:To treat night soil at low cost with fewer stages, easy operation, a small site area, and a small-sized apparatus by providing a preceding treating means and its circulating means, a night soil supply means, a succeeding treating means and its circulating means, and an ultrafiltration means. CONSTITUTION:Night soil, supplied into a preceding activated sludge process treating vessel 18 by a supply means 3, is successively treated with activated sludge in each chamber, and the treated liq. in the treating vessel 18 is circulated by circulating means 22 and 24. The treated liq. from the treating vessel 18 is successively treated with activated sludge in each chamber of the succeeding activated sludge process treating vessel 20. Furthermore, the treated liq. from the treating vessel 20 is filtered by an ultrafiltration device 42 having an ultrafiltration membrane, and separated into the filtrate and the liq. concentrate, a part of which is returned to the treating vessels 18 and 20. The other part of the liq. concentrate is recovered as excess sludge, a part of the filtrate is returned to the treating vessel 20, and the other part of the filtrate is discharged as the final effluent. Night soil can be treated by this method with fewer stages, easy operation, a small site area, and a compact apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a human urine treatment method that combines an activated sludge treatment method and an ultrafiltration method, and an apparatus therefor.

[Prior art]

The conventional activated sludge treatment method for treating human waste containing a large amount of organic substances, such as the standard low dilution two-stage activated sludge method, is as shown in Figure 4. After removing the sludge, it is stored (receiving and storage process), the dilution adjustment process (dilution adjustment process) in which the human waste (hereinafter referred to as the undiluted solution) is diluted to adjust or reduce the load on activated sludge, and the diluted sludge is activated. Activated sludge treatment is carried out in the sludge tank (activated sludge treatment process). In this case, the treatment process includes two stages: the first stage includes a first stirring and first aeration process, and the second stage includes a second stirring and second aeration process. Moreover, the acupuncture point treatment liquid in the first aeration process is circulated as a circulating liquid to the dilution adjustment process.

Next, the treated liquid from the activated sludge treatment step is subjected to sedimentation separation to separate suspended matter, and in this case, a part of the sedimented sludge is returned to the dilution adjustment step as return sludge. The other part of the separated sludge is discharged as surplus sludge to the outside of the system after dewatering, and the separated liquid is returned to the dilution adjustment process. Fine particles are coagulated and precipitated (coagulation separation process, in this case, the coagulated and separated sludge is discharged outside the system after dehydration, and the separated liquid is returned to the dilution adjustment process).Next, suspended solids are removed. (sand filtering process), then the dissolved substances are removed by activated carbon (activated carbon adsorption process), and disinfected (disinfection process) before being discharged.

[Problem that the invention seeks to solve]

As mentioned above, conventional human waste treatment methods require many steps in order to meet the water quality standards for effluent water, and require tanks or equipment for each of these steps, resulting in the following drawbacks: be.

Due to the large number of processes, operation management is complicated and 1) time-consuming. As the solid-liquid separation process uses precipitation separation process, coagulation separation process, and sand filtration process, on the other hand, the stock solution must be diluted about 10 times. Therefore, the processing equipment (activated sludge treatment tank, settling tank, etc.) becomes larger. Therefore, a relatively large site area and large construction costs are required. Furthermore, since the amount of dilution water used to dilute the stock solution is large, it is difficult to obtain it, and even if the concentration of the regulated component in the effluent water is large, even if the concentration of the regulated component satisfies the regulated value, the absolute amount of the regulated component released is large. Furthermore, when the activated sludge treatment liquid is subjected to solid-liquid separation using a settling tank, bulking may occur in the activated sludge, which may cause operational problems.

[Means for solving problems]

The present invention has been made in view of the above-mentioned circumstances, and has a small number of steps, a small site area, no need to dilute the stock solution, is small and inexpensive, and is capable of controlling the concentration and absolute amount of regulated components in effluent water. The object of the present invention is to provide a method and apparatus for treating human waste that has a small amount of waste and does not interfere with operation due to bulking. Below, based on one example, FIGS.
The structure and operation of the present invention will be explained with reference to FIG.

The human waste treatment method according to the present invention includes a pre-sequence treatment step in which the supplied human waste is sequentially treated with activated sludge in each chamber of a pre-stage activated sludge treatment tank that is composed of a plurality of chambers, and a a circulation step for circulating the treated liquid, a supply step for supplying the human waste to be treated to the activated sludge treatment tank in the earlier stage, and a supply step for supplying human waste to be treated to the activated sludge treatment tank in the earlier stage; A post-sequence treatment step in which the treated liquid from the activated sludge treatment tank is sequentially treated with activated sludge, and the treated liquid from the latter stage activated sludge treatment tank is filtered by an ultra-filtration device having an ultrafiltration membrane, and P liquid and A part of the concentrated liquid is returned to the activated sludge treatment tanks in the earlier and later stages, the other part of the concentrated liquid is recovered as surplus sludge, and a part of the F liquid is returned to the activated sludge treatment tanks in the latter stage. It is equipped with an ultrafiltration process in which the F liquid is returned to the activated sludge treatment tank and the other part of the F liquid is discharged as effluent water.

The human waste processing device according to the present invention is composed of a plurality of chambers,
A first activated sludge treatment tank for treating human waste with activated sludge in each chamber sequentially, a circulation means for circulating a treatment liquid in the first stage activated sludge treatment tank, and a supply means for supplying night soil to the first stage activated sludge treatment tank. and a downstream activated sludge treatment tank, which is composed of a plurality of chambers, in which the treated liquid from the preceding activated sludge treatment tank is sequentially treated with activated sludge in each chamber, and a downstream activated sludge treatment tank that restricts the treated liquid from the downstream activated sludge treatment tank. It is filtered through an outer filtration membrane and separated into liquid F and concentrated liquid. Part of the concentrated liquid is returned to the activated sludge treatment tanks in the previous and subsequent stages, and the other part of the concentrated liquid is recovered as surplus sludge and used as the undiluted solution. is equipped with an ultrafiltration device that returns a part of the F liquid to the latter treatment tank and discharges the other part as discharge water.

〔Example〕

First, in Fig. 1, the human waste (hereinafter referred to as the undiluted solution) that has been completely collected by a vacuum vehicle, etc. is received in the receiving tank 4, and the relatively large sand, stones, etc. contained in the undiluted solution are received in the receiving tank 4. is removed by sedimentation. The receiving tank 4 is connected to the storage tank 8 via a screen 10 and a fine screen 12.

The fine mesh screen 12 uses a screen with a mesh opening of 0.2■, and the screen 10 and the fine mesh screen 12
By passing through the liquid, relatively fine solids in the stock solution are removed. The stock solution that has passed through each screen is stored in a storage tank 8.
is stored in

In the storage tank 8, the concentration of the stock solution is made uniform.

Prior to supplying the stock solution to the pretreatment tank 18, it is preferable to remove insoluble solids (sludge) from the stock solution in order to reduce the load on the activated sludge and protect the ultrafiltration membrane. In this case, the undiluted solution is passed through a screen to remove the residue, and it is preferable to use a combination of a screen with large openings and a screen with small openings. It is preferable to use a screen with a small opening of 0.1 m to 0.5 m in order to remove a relatively fine amount of solid matter.

Examples of human waste include collected human waste (BOD 1
3,500 da/)), human waste septic tank sludge (BOD 7)
,000■/! degree), human waste digester desorbed fluid (BOD 2
, 400 ■/l), etc.

(without being substantially diluted) is sent to the activated sludge treatment tank 16 by the pump 14 at 30,017 days (Q).

The activated sludge treatment tank 16 has seven chambers (16).

16B, 16C, 16D, 16E, 16F.

16G).

The processing tanks 16 include a pre-processing tank 18 from the first chamber 16k to the fourth chamber 16D into which the stock solution flows, and a post-processing tank 18 in the seventh chamber 16G-4 from which the processing liquid flows out from the fifth chamber 16E. 2
It is divided into 0 and 0.

Each chamber is divided by a partition wall extending upward from the bottom so that the liquid level of the processing liquid in each chamber is adjusted sequentially from chamber 1 16A to chamber 7 16.
It is divided into lower sections along the G line in a step-like manner. Therefore, the processing liquid sequentially moves from the first chamber 16k to the seventh chamber 16G due to overflow. The pre-processing tank 18 may be divided into any number of chambers, such as three or four, as long as it is divided into a plurality of chambers.

As a modified example, as shown in FIG.
A first partition wall 17A extends upward from the bottom of the tank 16 as a base end, and a second partition wall 17A extends downward from here with the ceiling of the tank 16 as a base end. 17B are provided alternately, and by supplying air to the first chamber 16A, the third chamber 16C, and the fifth chamber 16H, the first chamber 16k is set to be aerobic, and the second chamber 16k is set to be anaerobic. The processing liquid is moved by overflow to the chamber 16B, and from the second chamber 16B and the fourth chamber 16D, which are set to be anaerobic, to the third chamber 16C and the fifth chamber, which are set to be aerobic.
The processing liquid may be moved to the chamber 16E by flowing through the bottom.

Further, the processing tank 16 may be provided with a defoaming spray 43 as shown in FIG. In other words, since the activated sludge treatment tank performs high-load processing, foaming may occur in each chamber, and bubbles may overflow and short-circuit to subsequent rooms, reducing treatment efficiency, so prevent foaming from occurring. This is to do so. In this case, a baffle plate 48 is also provided near the overflow part of the partition plate 46 of each room.
may be provided, and a defoaming spray 43 may be provided between the baffle plates. This configuration prevents bubbles from flowing into adjacent rooms.

Returning to FIG. 1, in the pre-treatment tank 18, the first chamber 16 and the fourth chamber 16D are connected by a circulation pipe 24. The circulation pipe 24 includes a circulation pump 22 for circulating a part of the processing liquid in the fourth chamber 16D to the 16 people in the first chamber.
is mediated. On the other hand, the storage tank 8 is connected to the circulation pipe f24 on the suction side of the circulation pump 22.

Therefore, the raw solution from the storage tank 8 is sent to the activated sludge treatment tank 16 at a flow rate Q while being mixed with the circulating treatment liquid.

At the tip of the circulation nozzle 24 in the first chamber 16A, there is an aeration injector (product name: Mitsui Vinyl Injector Complete Aeration Device) for introducing air when feeding the mixture of stock solution and circulating fluid. 26 are provided. Furthermore, the circulation pump 22 circulates a maximum of 120Q of processing liquid. In this embodiment, the cycle is approximately 40Q.

The raw solution sent to the activated sludge tank 16 is sent to the first tank together with the circulating fluid.
Starting from the chamber 16k, the water passes through each chamber while overflowing and reaches the seventh chamber. 2nd chamber 16B, 3rd chamber 16C1 4th
The chamber 16D1, the sixth chamber 16F, and the seventh chamber 16G are equipped with aeration devices 30, 3, which are normally used for supplying air, respectively.
1°32.36.38 is installed. These aeration devices are equipped with regulators (not shown) for independently regulating the amount of air supplied. The first chamber 16A and the fifth chamber 16E are maintained in an anaerobic atmosphere, and the second, third,
4th, 6th, and 7th chambers 16B, 16C, 16D, 1
6F.

and 16G are maintained in an aerobic atmosphere.

When the stock solution is supplied to the pre-processing tank, it is preferable to mix the stock solution with the processing liquid (circulating liquid) that is being circulated within the pre-processing tank.

Since an aeration injector is provided at the tip of the line in which the processing liquid is circulated in the direction in which the processing liquid flows, air is introduced into the processing liquid in this case.

Each room is equipped with an aeration device that can adjust the amount of air supplied to each room, and by arbitrarily adjusting the amount of air supplied to each room, the atmosphere in each room can be made relatively aerobic or anaerobic. can be set independently. In this case, for example, the atmosphere in each room can be set alternately to aerobic and anaerobic.

There is no need to dilute the stock solution when supplying it to the pre-treatment tank.

In the supply process, when the stock solution is supplied to the pre-treatment tank,
It is not limited to being supplied to one chamber. For example, when the chamber is divided into three or more as shown in FIG. 2, the first and third chambers may be supplied at the same time. Each chamber of the post-processing tank 20, like the pre-processing tank, may be divided into any number of chambers as long as it is plural, and can be independently set to a relatively aerobic or anaerobic atmosphere. It is preferable. Furthermore, as in this embodiment, it is preferable that the last chamber and the second to last chamber for supplying the treated liquid in the subsequent treatment tank to the ultrafiltration device are set to be aerobic. In this case, sticky anaerobic bacteria are not grown immediately before the ultrafiltration membrane, which prevents a decrease in filtration performance caused by the adhesion of these bacteria to the ultrafiltration membrane, and reduces the number of times the membrane is washed. can be reduced. In the treatment tank 16, an anaerobic chamber and an aerobic chamber are set in the first stage tank 18 and the second stage tank 20, and the combination of these anaerobic atmospheres and aerobic atmospheres effectively processes human waste into activated sludge.

The seventh chamber is connected to an ultrafiltration device 42 via a pipe 39 and a circulation pump 40. The ultrafiltration device 42 includes:
Polyacrylonitrile molecular weight cutoff 15,000 to 2
0,000 ultrafiltration membrane,. -'Alf -5y Eye 1, 7, 2, 8 is waving. The treated liquid is passed through the ultrafiltration membrane in a cross-flow manner and separated into a p liquid and a concentrated liquid.

An ultrafiltration device 42 using an ultrafiltration membrane is connected to an activated carbon layer 44 via a dirty liquid pipe 43.

An F liquid return pipe 45 for returning part of the F liquid to the seventh chamber is branched from the dirty liquid pipe. Furthermore, a return nozzle 46 is provided for returning the concentrated liquid from the ultrafiltration device 42 to the fourth chamber 16D of the first stage tank 16 and the seventh chamber 16G of the second stage tank 18. An excess sludge i4 ide 48 is branched from the return flow f46 to discharge the remainder of the concentrated liquid as excess sludge to the outside of the system. Part of the above sewage (
After Q) passes through the activated carbon layer 44 to remove dissolved substances in the P liquid, it is discharged as effluent water, and the other part (approximately 0.2Q) of the F liquid passes through the via '45 to the seventh chamber 16.
Returned to G.

On the other hand, the concentrated liquid is stored in the fourth chamber 16D of the front stage tank 18 and the rear stage tank 20.
are returned to the seventh chamber 16G at a flow rate of about 10Q and about 60Q, respectively.

The ultrafiltration membrane used has a molecular weight cut-off of 1,000 to 3,000,000.

The F solution from the ultrafiltration membrane is discharged as treated water as it is, but a part of the concentrate from the ultrafiltration device that removes dissolved substances in the sewage is used to control the activated sludge concentration and to In order to activate the sludge and repeatedly decompose the recalcitrant substances, sludge in the range of 20Q to 120Q is usually taken out of the system as surplus sludge in the front and rear tanks. Post-processing tank (7th
The treated liquid in the chamber) is supplied to the ultrafiltration device 42, where the treated liquid is highly concentrated as a concentrated liquid, and is returned to the pre- and post-processing tanks, so that hardly decomposable organic substances in the treated liquid are removed. It is also decomposed repeatedly or over a long period of time by activated sludge.

The activated sludge concentration could not be easily increased, but according to the present invention, since no settling tank is used, the activated sludge concentration (
;jigs) can be easily transferred to the IC, and high-load, high-concentration operation is possible. For example, the conventional activated sludge concentration (M
L, 8g > was 4,000 to 8.000 my/l, but in the present invention it was 6,000 to 25.00011
π Eagle set to 19/l. In this example, 12.000 to 1
It was set to 3,000 to η.

The present invention is not limited to the above-mentioned scope, but can be modified in various ways without departing from the spirit of the present invention.

The results of human waste treatment according to this example will be explained with reference to Table 1.

In the storage tank 8 shown in FIG. 1, the undiluted solution whose concentration has been adjusted to a substantially uniform level (not diluted), the sewage that has passed through the ultrafiltration membrane, and the discharged water that has passed through the activated carbon layer 44 are collected, and the quality of each water,
That is, BOD (biochemical oxygen demand), SS (suspended solids), C0D (chemical oxygen demand), TN (total nitrogen), coliform bacteria count, and chromaticity were measured. The measurement results are shown in Table 1.

As is clear from Table 1, in this example, effluent water of good quality, which was lower than the conventional value, was obtained.

What is particularly noteworthy is that in the conventional method, the supply amount and discharge amount to the activated sludge tank are both IOQ, but in this example, since the stock solution is not diluted, both the supply amount and the discharge amount are Q.
This is about 1710 compared to the conventional one. Therefore, the absolute discharge amount of the regulated component is also about 1710, which is the conventional value. Incidentally, the absolute amounts of BOD etc. shown in Table 1 are values for Q=300J/day.

Small size, easy to operate sb No need for large site area sb
Human waste can be processed at low cost with a small device.

In other words, since there is no need to dilute the stock solution (there is no need to introduce dilution water from outside the system), both the processing amount and the discharge amount are Q (same as the stock solution supply amount), which is about 1710 liters compared to the conventional method. Therefore, even if the concentration of the regulated components in the effluent is the same as in the conventional method, the absolute amount of the regulated components in the effluent is reduced to about 1/10, and each part of the equipment, such as the activated sludge treatment tank, pump, and piping, is reduced to a shed. be able to.

Since an ultrap filter membrane is used, the effluent water contains suspended solids (88
), the water quality can be made to be of good quality, containing almost no pathogenic bacteria, dissolved polymeric organic matter, etc.

Therefore, since the settling tank, coagulation sedimentation tank, sand filtration tank, and related processes of the conventional method are not necessary, the construction cost and site area of the treatment equipment are greatly reduced, and operation management is also facilitated. For example, in general, in conventional methods, the total volume from the activated sludge treatment tank to the sand filtration tank is 3
Although it is designed to be about 0Q, according to the present invention, it is about 7Q,
That is, the volume can be reduced to about 174 compared to the conventional method.

Fig. 2 is a schematic sectional view showing another example of the processing tank, Fig. 3 is a schematic sectional view of a processing tank according to another modification, and Fig. 4 is a conventional human waste treatment. It is a process chart for explaining a method.

3... Supply means, 18... Pre-treatment tank, 20...
Post-processing tank, 42...ultrafiltration device.

Applicant's agent Patent attorney Takehiko Suzue, Commissioner of the Patent Office
Michibe Uga, Patent Application No. 59-267725 2, Title of the invention: Human waste disposal method and its device 3, Relationship with the case of the person making the amendment Patent applicant 5, Spontaneous amendment 7, Contents of the amendment (1) Description In the 6th line of page 24, add the following sentence after ending ``It is possible.''

``In addition, activated carbon layers as adsorbents generally adsorb suspended solids (SS), water-soluble organic substances (COD), inorganic salts, phosphate ions, etc. in liquids, but in this example, an ultrafiltration membrane was used. Since the passed F liquid is supplied to the activated carbon layer,
Suspended solids and polymeric organic substances that may cause clogging of the activated carbon layer or decrease in adsorption capacity can be removed in advance by the ultrapolar membrane. Therefore, according to this embodiment, the target material can be efficiently removed while maintaining the performance of the activated carbon layer. " cormorant

Claims (1)

[Scope of Claims] 1. A pre-sequence treatment step in which the supplied human waste is sequentially treated with activated sludge in each chamber of the pre-stage activated sludge treatment tank which is composed of a plurality of chambers, and a circulation step for circulating the treated solution, a supply step for supplying human waste to be treated to the activated sludge treatment tank in the previous stage, and a step in which the activated sludge treatment tank in the former stage is circulated in each chamber of the activated sludge treatment tank in the latter stage, which is composed of a plurality of chambers. A post-sequence treatment step in which the treated liquid from the sludge treatment tank is sequentially treated with activated sludge, and the treated liquid from the latter activated sludge treatment tank is filtered by an ultrafiltration device having an ultrafiltration membrane, and the filtrate and concentration are concentrated. Part of the concentrated liquid is returned to the activated sludge treatment tanks in the earlier and later stages, the other part of the concentrated liquid is recovered as surplus sludge, and part of the filtrate is returned to the activated sludge treatment tanks in the latter stage. A method for treating human waste comprising an ultrafiltration step of returning the filtrate to a sludge treatment tank and discharging the other part of the filtrate as effluent water. 2. In the circulation step, the treatment liquid is circulated by a pump, and in the supply step, the human waste to be treated is supplied to the suction side of the pump, and the human waste is mixed with the treatment liquid and supplied to the preceding activated sludge treatment tank. A human waste disposal method according to claim 1, characterized in that: 3. In the circulation step, the treatment liquid is returned to the activated sludge treatment tank at the previous stage via an aeration injector, and is mixed with air by the aeration injector. The human waste disposal method according to any one of the items. 4. The aeration amount of each chamber of the first and second activated sludge treatment tanks is adjusted by an aeration injector or a diffuser, and the chambers are arbitrarily and independently maintained in an aerobic or anaerobic atmosphere. The method for treating human waste according to any one of Items 1 to 3. 5. The human waste treatment method according to any one of claims 1 to 4, wherein the human waste to be treated is not diluted in the supply step. 6. The concentration of activated sludge in the first stage and second stage activated sludge treatment tanks is 6,000 mg/l to 25,000 mg/l.
6. The human waste processing method according to claim 1, wherein the human waste treatment method is set to l. 7. The human waste treatment method according to claim 4, wherein in the post-sequence treatment step, the last and penultimate chambers of the downstream activated sludge treatment tank are maintained in an aerobic atmosphere. 8. A pre-stage activated sludge treatment tank composed of a plurality of chambers, in which human waste is sequentially treated with activated sludge in each chamber, a circulation means for circulating the treatment liquid in the pre-stage activated sludge treatment tank, and the pre-stage activated sludge treatment tank. a supply means for supplying human waste to a treatment tank; a rear activated sludge treatment tank which is comprised of a plurality of chambers and sequentially processes the treated liquid from the earlier activated sludge treatment tank as activated sludge in each chamber; The treated liquid from the sludge treatment tank is filtered by an ultrafiltration membrane and separated into a filtrate and a concentrated liquid. A part of the concentrated liquid is returned to the activated sludge treatment tanks in the previous and subsequent stages, and other parts of the concentrated liquid are an ultrafiltration device for recovering part of the sludge as surplus sludge, returning a part of the filtrate to the latter treatment tank, and discharging the other part of the filtrate as effluent water. 9. The circulation means includes a pump for circulating the treatment liquid, and the supply means includes a conduit for supplying the human waste to be treated to the suction side of the pump, and the human waste to be treated is mixed with the treatment liquid. The human waste treatment apparatus according to claim 8, wherein the human waste is supplied to the activated sludge treatment tank in the preceding stage. 10. The circulation means includes a line for circulating the treatment liquid, and an aeration injector is provided at the tip of the line in the direction in which the treatment liquid flows, and when the treatment liquid is returned to the preceding treatment tank, the aeration injector is installed. The human waste treatment device according to any one of claims 8 and 9, characterized in that the human waste is mixed with air by. 11. In each chamber of the first stage and second stage activated sludge treatment tank,
Any one of claims 8 to 10, characterized in that an aeration injector or diffuser is provided that can adjust the amount of aeration, and each chamber is arbitrarily and independently maintained in an aerobic or anaerobic atmosphere. The human waste treatment device according to item 1. 12. Claims 8 to 1, characterized in that the human waste to be treated in the supply means is not diluted.
The human waste treatment device according to any one of Item 1. 13. The activated sludge concentration in each of the first and second chambers is 6.
13. The human waste treatment device according to any one of claims 8 to 12, characterized in that the amount of waste is 000 mg/l to 25,000 mg/l. 14. The human waste treatment apparatus according to claim 11, wherein the last and second to last chambers of the downstream activated sludge treatment tank are maintained in an aerobic atmosphere.