Recycling system of sewage and sludge treatment filtrate
Technical Field
The utility model relates to a filter liquor recycling system and a filter liquor recycling method of a dehydrator, in particular to a recycling system for filter liquor in sewage and sludge treatment.
Background
At present waste incineration power plant, mud carries out mud-water separation through the hydroextractor and handles the back, and the mud that produces is gone into the stove system through the dispersion and is handled, and the filtrating flows back and is handled to anterior segment clarification plant. Although the sludge treatment system can treat and convey the sludge, the following problems still exist: the water for washing the dehydrator and the water for dispensing are both tap water, a large amount of external water sources are introduced into the system, so that water resource waste is caused, the treatment pressure of a rear-section system is increased, and the overall treatment cost is increased.
SUMMERY OF THE UTILITY MODEL
In order to solve the problems of the prior art, the utility model provides a recycling system and a recycling method of sewage and sludge treatment filtrate, wherein the recycling system comprises a sewage treatment system and a sludge treatment system; the recycling method comprises a sewage treatment step and a sludge treatment step. Through setting up hydroextractor reflux system, the clear liquid backward flow of storing up the pond flows back to centrifugal dehydrator through hydroextractor washing unit and hydroextractor dispensing device, utilizes the medicament that water resource and system were thrown to the utmost, further reduces the operation cost.
The utility model solves the technical problem by adopting the technical scheme that a recycling system for sewage and sludge treatment filtrate comprises a sewage treatment system and a sludge treatment system;
according to the direction that sewage flows, sewage treatment system includes in proper order: the system comprises a grid, a sewage adjusting tank, a mixing tank, a clarifying device, an intermediate water tank and an evaporation system;
the mixing pool is also connected with a lime and PAM feeding system;
the sludge outlets of the clarification device and the intermediate water tank are connected to a sludge tank of the sludge system;
according to the flowing direction of the sludge, the sludge treatment system is sequentially connected with a sludge pool, a sludge concentration tank, a centrifugal dehydrator, a filtrate buffer tank, a filtrate precipitator, a clarified liquid water tank and a storage tank; a mud bucket is also arranged;
the sludge outlet of the centrifugal dehydrator is connected with the sludge hopper;
a clear liquid outlet of the reservoir is connected to the clarification device;
a clear liquid outlet of the sludge concentration tank is connected to the clear liquid water tank;
the sludge outlets of the filtrate buffer tank and the filtrate precipitator are connected to the sludge inlet of the sludge concentration tank;
characterized by still sets up hydroextractor return-flow system, hydroextractor return-flow system includes: the dewatering machine acid cleaning device and a filtrate circulating pipeline arranged between the dewatering machine acid cleaning device and the centrifugal dewatering machine.
Preferably, a dehydrator flushing device and a flushing return pipeline flowing through the dehydrator flushing device are further arranged; hydroextractor dispensing device and flow through the backflow pipeline that dispenses of hydroextractor dispensing device.
Preferably, one end of the flushing return pipeline is connected to a clear liquid outlet of the storage tank, and the other end of the flushing return pipeline is connected to an inlet of the centrifugal dehydrator; one end of the dispensing backflow pipeline is connected to a clear liquid outlet of the storage tank, and the other end of the dispensing backflow pipeline is connected to an inlet of the centrifugal dehydrator.
A recycling method of sewage and sludge treatment filtrate, which comprises a sewage treatment step and a sludge treatment step,
the sewage treatment steps sequentially comprise: impurity filtering by a grid, sewage regulation, medicine adding and mixing, clarification treatment, intermediate precipitation, evaporation and other steps; in the dosing and mixing step, lime and PAM (flocculating agent, i.e. polyacrylamide) are added to the mixing tank simultaneously; respectively conveying the sludge and the scum generated in the clarification treatment and intermediate sedimentation steps to the sludge tank, and adding lime into the sludge tank;
the sludge treatment steps sequentially comprise: collecting sludge, concentrating the sludge, centrifugally dewatering, buffering filtrate, precipitating the filtrate, clarifying effluent, collecting clarified liquid and the like;
conveying dewatered sludge produced after the centrifugal dewatering step to the hopper;
delivering clarified liquid generated in the sludge concentration step process to the storage tank;
after the sludge concentration step, adding a defoaming agent into the centrifugal dehydrator for centrifugal dehydration;
respectively conveying the sludge generated in the filtrate buffering and filtrate precipitating steps to the sludge concentration tank;
after the clarified liquid collection step, returning a portion of the collected clarified liquid to the clarifier apparatus,
the method is characterized in that after the clear liquid collecting step, one part of the collected clear liquid preferentially flows back to the dehydrator through the dehydrator flushing device, one part of the collected clear liquid preferentially flows back to the dehydrator through the dehydrator dispensing device, and the rest part of the collected clear liquid returns to the clearing device.
Preferably, a part of the filtrate generated after the centrifugal dewatering step flows into the filtrate precipitator and another part of the filtrate flows through the acid washing device of the dewatering machine through the circulating pipeline and then flows back to the centrifugal dewatering machine again, thereby forming a circulation.
Preferably, at the initial stage of starting the centrifugal dehydrator, the dehydrator flushing device and the dehydrator dispensing device need to be flushed and dispensed with tap water, and after the centrifugal dehydrator runs stably, the centrifugal dehydrator is switched to the clear liquid in the storage tank.
Has the advantages that: the utility model provides a recycling system of sewage and sludge treatment filtrate, which is also provided with a dehydrator backflow system, wherein clear liquid backflow of a storage tank flows back to a centrifugal dehydrator through a dehydrator flushing device and a dehydrator dispensing device, so that water resources and medicaments added by the system are utilized to the maximum extent, and the operation cost is further reduced; and the overhaul period of the centrifugal dehydrator is prolonged through acid washing, and the running stability of the equipment is improved.
Drawings
Fig. 1 is a schematic diagram of a system layout according to an embodiment of the prior art.
Fig. 2 is a schematic diagram of a system arrangement according to an embodiment of the present invention.
FIG. 3 is a schematic process flow diagram of one embodiment of the present invention.
FIG. 4 is a schematic process flow diagram of another embodiment of the present invention.
In fig. 1:
11. a sludge tank; 12. a sludge concentration tank; 13. a centrifugal dehydrator; 14. a filtrate buffer tank; 15. a filtrate precipitator; 16. a clear liquid tank; 17. a storage pool; 18. a mud bucket;
21. a grid; 22. a sewage adjusting tank; 23. a mixing tank; 24. a clarification device; 25. a middle water tank; 26. an evaporation system;
31. a dehydrator pickling device; 32. a dehydrator washing device; 33. a hydroextractor dispensing device;
31.1, a filtrate circulating pipeline, 32.1 a flushing return pipeline and 33.1 a dispensing return pipeline.
Detailed Description
Fig. 1 is a schematic diagram of a system layout according to an embodiment of the prior art. The figure shows a recycling system of sewage and sludge treatment filtrate, which comprises a sewage treatment system and a sludge treatment system.
According to the direction that sewage flowed, sewage treatment system includes in proper order: a grating 21, a sewage adjusting tank 22, a mixing tank 23, a clarifying device 24, an intermediate water tank 25 and an evaporation system 26. The mixing tank 23 is also connected with a lime and PAM feeding system, and the sludge outlets of the clarification device 24 and the intermediate water tank 25 are connected with the sludge tank of the sludge system. According to the flowing direction of the sludge, the sludge treatment system is sequentially connected with a sludge pool 11, a sludge concentration tank 12, a centrifugal dehydrator 13, a filtrate buffer tank 14, a filtrate precipitator 15, a clarified liquid water tank 16 and a storage pool 17; a sludge hopper 18 is also provided. The sludge outlet of the centrifugal dehydrator 13 is connected with the sludge hopper 18; a clear liquid outlet of the reservoir 17 is connected to a clarifying device 24, a clear liquid outlet of the sludge concentration tank 12 is connected to the clear liquid water tank 16, and sludge outlets of the filtrate buffer tank 14 and the filtrate precipitator 15 are connected to a sludge inlet of the sludge concentration tank 12;
in the present example, the operation of the wastewater treatment system is shown as follows: the sewage is conveyed to an evaporation system 26 through a grating 21, a sewage adjusting tank 22, a mixing tank 23, a clarification device 24 and an intermediate water tank 25 in sequence. Wherein the sludge produced in the clarifier 24 and the intermediate basin 25 is transferred to the sludge basin 11. In this example, lime and PAM are charged into the mixing tank 23.
In the present example, the operation of the sludge treatment system is shown as follows: the sludge passes through a sludge pool 11, a sludge concentration tank 12, a centrifugal dehydrator 13, a filtrate buffer tank 14, a filtrate precipitator, a clarified liquid water tank 16 and a storage tank 17 in sequence, and then the liquid in the storage tank 17 is conveyed by a pump for reuse to a clarification device 24. A hopper 18 is provided after the centrifugal dehydrator 13, and sludge generated by the centrifugal dehydrator 13 is sent to the hopper 18. The utility model suggests that a stirring device (such as a submersible stirrer or other devices) can be arranged in the sludge tank 11 to stir, mix and equalize the amount of the sludge entering the sludge tank 11, and then the sludge is pumped out to a sludge concentration treatment device. When the sludge is sent into the sludge concentration treatment device, a defoaming agent and the like can be added to take out foams in the sludge, so that the sludge is convenient to concentrate and precipitate.
The utility model suggests that the sludge treatment system may include one or more sludge concentration tanks 12, and a stirring device (such as a stirrer, a screw pump or other stirring equipment) may be disposed in the sludge concentration tank 12 to perform a concentration treatment on the sludge entering the sludge concentration tank 12. In this embodiment, a sequencing batch operation may be used, such as feeding and stirring for 6-10 hours, settling for 4-8 hours, draining for 1-2 hours, stirring for 0.5-1 hour, and pumping sludge for 8 hours.
In this example, the filtrate outlet of the sludge concentration tank 12 is connected to the inlet of the centrifugal dehydrator 13, and the filtrate concentrated in the sludge concentration tank 12 is output to the centrifugal dehydrator 13 to be centrifugally dehydrated. The sludge dewatered by the centrifugal dewatering machine 13 is discharged to a hopper 18, and the filtrate is output to a filtrate buffer tank 14. The filtrate is subjected to energy dissipation treatment in a filtrate buffer tank 14, the sludge after energy dissipation is periodically or irregularly discharged to a sludge concentration tank 12, and the filtrate is output to a filtrate precipitator 15. The filtrate is subjected to mud-water separation and precipitation in a filtrate precipitator 15, the precipitated sludge is periodically or irregularly discharged to a sludge concentration tank 12, and the filtrate is output to a clarified liquid water tank 16. The liquid in the clarified liquid tank 16 is delivered to the reservoir 17 by a pump or the like, and the clarified liquid in the reservoir 17 flows back to the clarifier device 24.
Through setting up the sludge concentration jar, can effectually reduce the moisture content of mud, avoid getting into centrifugal dehydrator 13's the change on a large scale of mud moisture content, avoided putty, need the defect of special messenger's management, improved the reliability of system operation.
The present invention suggests that the centrifugal dehydrator 13 may be equipped with a PLC control system to realize automatic control of the centrifugal dehydrator 13.
In the prior art, after the sludge is subjected to solid-liquid separation treatment by a dehydrator, the generated filtrate directly flows back to a clarifying device, cannot be recycled to the maximum extent, and cannot fully utilize water resources and medicaments.
Fig. 2 is a recycling system of sewage and sludge treatment filtrate provided by the present invention, and fig. 2 shows that, unlike the prior art, a dehydrator reflux system is further provided, wherein the dehydrator reflux system comprises a dehydrator acid cleaning device 31 and a filtrate circulation pipeline 31.1 arranged between the dehydrator acid cleaning device 31 and the centrifugal dehydrator 13; a dehydrator 32 and a rinse return line 32.1 passing through the dehydrator 32; a dehydrator dispenser 33 and a dispensing return line 33.1 passing through the dehydrator dispenser 33.
One end of the washing return pipeline 32.1 is connected to a clear liquid outlet of the reservoir 17, and the other end is connected to an inlet of the centrifugal dehydrator 13; one end of the dispensing reflux pipe 33.1 is connected to the clear liquid outlet of the reservoir 17 and the other end is connected to the inlet of the centrifugal dehydrator 13.
The clarified liquid in the reservoir 17 partially flows back to the clarifying tank device 24, partially flows back to the centrifugal dehydrator 13 through the dehydrator 32 via the rinsing return pipe 32.1, and partially flows back to the centrifugal dehydrator 13 through the dehydrator 33 via the dispensing return pipe 33.1.
In this example, the dehydrator reflux system further comprises a reflux pipe 31.1 passing through the dehydrator pickling apparatus 31, wherein one end of the reflux pipe 33.1 is connected to the outlet of the centrifugal dehydrator 13 and the other end is connected to the inlet of the centrifugal dehydrator 13.
FIG. 3 is a schematic process flow diagram of one embodiment of the present invention. In this embodiment, a method for recycling sewage and sludge treatment filtrate comprises a sewage treatment step and a sludge treatment step.
The sewage treatment steps sequentially comprise: impurity filtering by a grid, sewage regulation, medicine adding and mixing, clarification treatment, intermediate precipitation, evaporation and other steps; in the dosing and mixing step, lime and PAM (flocculant, i.e., polyacrylamide) are simultaneously added to the mixing tank 23; the sludge and the scum produced in the clarification treatment and the intermediate sedimentation step are separately transferred to a sludge tank 11, and lime is added to the sludge tank 11.
The sludge treatment steps sequentially comprise: collecting sludge, concentrating the sludge, centrifugally dewatering, buffering filtrate, precipitating the filtrate, clarifying effluent, collecting clarified liquid and the like;
the dewatered sludge produced after the centrifugal dewatering step is conveyed to the hopper 18;
the clarified liquid produced during the sludge concentration step is conveyed to the reservoir 17;
after the sludge concentration step, an antifoaming agent is added to the centrifugal dehydrator 13 to perform centrifugal dehydration;
the sludge generated in the filtrate buffering and filtrate precipitating steps is respectively conveyed to a sludge concentration tank 12;
after the supernatant collection step, a portion of the collected supernatant is returned to the clarifier tank assembly 24.
In the present example, unlike the prior art, a part of the collected supernatant is returned to the dehydrator 13 through the dehydrator 32 after the supernatant collecting step, and a part of the collected supernatant is returned to the dehydrator 13 through the dehydrator dispenser 33. The remainder is returned to the clarification device 24 to maximize the use of water and chemicals.
FIG. 4 is a schematic process flow diagram of another embodiment of the present invention. In the example shown in fig. 4, in contrast to the example of fig. 3, the filtrate produced after the centrifugal dewatering step flows partly into the filtrate settler 15 and partly back into the centrifugal dewatering machine 13 after passing through the dewatering machine pickling device 31 via the filtrate circulation line 31.1, thus forming a circulation.
The present invention suggests that the dehydrator cleaning device 32 and the dehydrator dispensing device 33 need to be cleaned and dispensed with tap water at the initial stage of starting the centrifugal dehydrator, and the clear liquid in the reservoir 17 is switched after the centrifugal dehydrator is stably operated.