Pretreatment device and sewage treatment system

Abstract

The utility model discloses a pretreatment device and a sewage treatment system. The pretreatment device at least comprises a coagulative precipitation tank, a hydrolysis acidification tank and a hydrolysis precipitation tank which are sequentially arranged and communicated along the sewage treatment direction, the hydrolysis acidification pool is provided with three reaction chambers which are sequentially communicated, the middle part of each reaction chamber is provided with a lower filter plate and an upper filter screen, and a filler layer is arranged between the lower filter plate and the upper filter screen; wherein a vertical shaft channel for sewage to circulate is arranged between the adjacent reaction chambers, the top of the vertical shaft channel is communicated with the top of the previous reaction chamber, and the bottom of the vertical shaft channel is communicated with the bottom of the next reaction chamber. By combining the processes of coagulation, hydrolysis, precipitation and the like and utilizing the design of the multi-stage reaction chamber and the vertical shaft channel, compared with a traditional hydrolysis acidification pool, the sewage treatment device can more effectively remove suspended solids and organic pollutants in sewage, the pretreatment efficiency and the pretreatment effect of the sewage are improved, the burden of subsequent treatment facilities is relieved, and the treatment cost is reduced. The overall treatment efficiency and stability of a sewage material system are improved, so that the requirement of high-concentration biochemical sewage treatment is met.

Description

Technical Field

[0001] The utility model relates to an industrial sewage treatment system, in particular to a pretreatment device and a sewage treatment system. Background Art

[0002] Biochemical wastewater is mostly high-concentration organic wastewater that is difficult to treat. It has the characteristics of many difficult-to-degrade substances, low biodegradability, high salinity, and high toxicity. It is difficult to meet the standards by direct biochemical treatment, and usually pretreatment is required before biochemical treatment. Hydrolysis and acidification treatment refers to controlling the anaerobic process in the hydrolysis and acidification stages, and using facultative hydrolytic acid-producing bacteria to convert complex organic matter into simple organic matter. The hydrolysis and acidification process plays a very important role in reducing the toxicity of organic wastewater and improving the biodegradability of wastewater for subsequent treatment processes.

[0003] A Chinese invention patent with announcement number CN108658394A discloses a domestic sewage pretreatment device, which relates to the technical field of sewage treatment equipment, including a pre-filtration tank and a hydrolysis acidification tank. The pre-filtration tank and the hydrolysis acidification tank are arranged in parallel underground and are connected by a diversion pipe. The water inlet of the pre-filtration tank is provided with a filter grid and filter material is filled inside. The pre-filtration tank is provided with an inlet pipe connected to the sewage pipe network. The pre-filtration tank is connected to the hydrolysis acidification tank through a diversion pipe; and the hydrolysis acidification tank provided with an outlet pipe is provided with an elastic filler.

[0004] The existing traditional hydrolysis acidification tanks are mainly used for domestic sewage, but they are unable to meet the current pretreatment requirements of high-concentration biochemical wastewater, which affects the effluent quality and subsequent treatment processes. It is necessary to innovate and improve the hydrolysis acidification tanks to meet the needs of biochemical wastewater treatment. Utility Model Content

[0005] In order to overcome the above technical defects, the utility model provides a pretreatment device, a sewage treatment system

[0006] In order to solve the above problems, the utility model is implemented according to the following technical solutions:

[0007] In a first aspect, the utility model provides a pretreatment device, which at least comprises a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank which are sequentially arranged and connected along the sewage treatment direction;

[0008] The hydrolysis acidification tank is provided with three reaction chambers connected in sequence, a lower filter plate and an upper filter screen are provided in the middle of each reaction chamber, and a packing layer is provided between the lower filter plate and the upper filter screen;

[0009] Wherein, a vertical shaft channel for sewage circulation is arranged between adjacent reaction chambers, the top of the vertical shaft channel is communicated with the top of the previous reaction chamber, and the bottom of the vertical shaft channel is communicated with the bottom of the next reaction chamber.

[0010] Preferably, the thickness of the packing layer is 2.5-3 m.

[0011] Preferably, the filler layer comprises a suspended ceramsite layer located at an upper layer and an activated carbon filler layer located at a lower layer.

[0012] Preferably, the particle size of the suspended ceramsite is 12 to 16 mm; the thickness of the activated carbon filler layer is 50 cm, and the particle size of the activated carbon is 6 to 8 mm.

[0013] Preferably, there are two coagulation sedimentation tanks, two hydrolysis acidification tanks and two hydrolysis sedimentation tanks.

[0014] Preferably, the hydrolysis sedimentation tank adopts an upflow water outlet structure, and the hydrolysis sedimentation tank is provided with an inclined tube sedimentation structure.

[0015] Preferably, the pretreatment device comprises a coarse screen room, a regulating tank, a lifting pump room, a fine screen room, an aerated grit chamber, a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank which are sequentially arranged and connected along the sewage treatment direction;

[0016] The pretreatment device also includes an emergency pool, which is connected to the regulating pool.

[0017] In a second aspect, the utility model further provides a sewage treatment system, comprising a pretreatment device as described in the first aspect.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] The utility model provides a pretreatment device, which at least comprises a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank which are sequentially arranged and connected along the sewage treatment direction; the hydrolysis acidification tank is provided with 3 reaction chambers which are sequentially connected, a lower filter plate and an upper filter screen are arranged in the middle of each reaction chamber, and a packing layer is arranged between the lower filter plate and the upper filter screen; wherein a vertical shaft channel for sewage circulation is arranged between adjacent reaction chambers, the top of the vertical shaft channel is connected with the top of the previous reaction chamber, and the bottom of the vertical shaft channel is connected with the bottom of the next reaction chamber.

[0020] The pretreatment device provided by the utility model at least includes a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank, which are located at the starting position of the sewage treatment device and are used for coagulation and sedimentation, and can effectively precipitate and remove suspended matter in high-concentration biochemical sewage. The design of multiple interconnected reaction chambers and packing layers set in the hydrolysis acidification tank increases the contact area between organic matter and microorganisms, and accelerates the degradation and acidification reaction of organic matter. This helps to reduce the concentration of organic matter, reduce the organic load of sewage, and provide favorable water quality conditions for subsequent treatment processes. At the same time, a hydrolysis sedimentation tank is set after the hydrolysis acidification tank to further hydrolyze organic matter and precipitate residual suspended matter to purify sewage.

[0021] By combining coagulation, hydrolysis and sedimentation processes and utilizing the design of multi-stage reaction chambers and vertical shaft channels, the system can more effectively remove suspended solids and organic pollutants from sewage than traditional hydrolysis and acidification tanks, thereby improving the efficiency and effect of sewage pretreatment, reducing the burden on subsequent treatment facilities, and improving the overall treatment efficiency and stability of the sewage material system to meet the needs of high-concentration biochemical sewage treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0023] Figure 1 It is a schematic diagram of the composition of the sewage treatment system of the utility model;

[0024] Figure 2 It is a structural schematic diagram of the hydrolysis acidification tank of the utility model;

[0025] In the figure:

[0026] 10-hydrolysis acidification tank, 11-lower filter plate, 12-upper filter screen, 13-filling layer;

[0027] 20-Hydrolysis sedimentation tank, 21-Inclined tube sedimentation structure. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0029] like Figure 1-2 As shown, the preferred structure of a pretreatment device and a sewage treatment system described in the utility model.

[0030] like Figure 1As shown, the composition diagram of the sewage treatment system of the utility model and the process flow diagram of sewage treatment. The sewage treatment system includes a pretreatment device, and a membrane grid channel and A / O biological pool, MBR membrane pool, ozone contact oxidation pool, disinfection pool, pasteurization metering tank and recycled water pump room connected to the pretreatment device.

[0031] like Figure 1 As shown, the pretreatment device includes a coarse screen room, a regulating tank, a lifting pump room, a fine screen room, an aerated grit tank, a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank, which are sequentially arranged and connected along the sewage treatment direction; the pretreatment device also includes an emergency tank, which is connected to the regulating tank. The pretreatment device is divided into primary pretreatment and secondary pretreatment. The primary pretreatment mainly adopts a regulating tank + aerated grit tank + coagulation sedimentation tank. The secondary pretreatment mainly adopts a hydrolysis acidification tank + hydrolysis sedimentation tank.

[0032] In view of the high-concentration biochemical organic wastewater, the water quality and quantity change greatly, the water quality composition is complex, there are many harmful substances, many difficult-to-biodegrade substances, poor biodegradability, and high salt content. The sewage treatment adopts primary pretreatment, secondary pretreatment, and tertiary deep treatment processes. The primary pretreatment section adopts a regulating tank + aerated grit chamber + coagulation sedimentation tank, in which the regulating tank can balance the impact load of water quality and quantity; the secondary pretreatment adopts a hydrolysis acidification tank + hydrolysis sedimentation tank, and is combined with a multi-stage A / O biochemical tank. The sewage has strong biochemical performance and realizes the optimization of monomer functions; the deep treatment adopts MBR (membrane bioreactor) + ozone advanced oxidation technology, and the effluent water quality standard is high and the quality is relatively stable. The sludge treatment adopts chemical conditioning combined with a "high-pressure diaphragm filter press" to dehydrate the sludge. The deodorization process adopts the "ion deodorization method".

[0033] In a specific implementation, the coarse screen room, regulating tank, emergency tank and lifting pump room are set up in one. The coarse screen uses two stainless steel rotary mechanical screens with a screen gap of 15mm; the regulating tank is divided into two compartments with an effective retention time of 8h; the lifting pump room is equipped with 6 submersible sewage pumps, 4 for use and 2 for backup, and the single pump parameter is: Q=525m 3 / h, H=19m, N=45kW; the emergency pool is located above the regulating pool, with an effective residence time of 10h.

[0034] In a specific implementation, the fine grid and aeration grit chamber are provided with one. The fine grid uses two stainless steel circulating tooth rakes, and the grid gap is 5mm; the maximum flow hydraulic retention time of the aeration grit chamber is 5.5min, and the horizontal flow velocity v=0.055m / s.

[0035] In a specific implementation, two coagulation sedimentation tanks are set up, each with a capacity of 25,000 m 3 / d. Mixing time T = 60s, flocculation time T = 15.2min, hydraulic load on sedimentation tank surface 1.5m3 / m 2 ·h, sedimentation tank residence time T = 2h.

[0036] In a specific implementation, two hydrolysis acidification tanks are set up, each of which is divided into three compartments, and each compartment is equipped with a high-efficiency pulse water distributor bell generator, a water distribution system and a sludge discharge system. A single hydrolysis acidification tank is equipped with a front return sludge adsorption channel, where the membrane tank return sludge is mixed with 10% of the influent water.

[0037] Among them, Figure 2 As shown, the hydrolysis acidification tank is provided with 3 reaction chambers connected in sequence, a lower filter plate 11 and an upper filter screen 12 are provided in the middle of each reaction chamber, and a packing layer 13 is provided between the lower filter plate and the upper filter screen; wherein, a vertical shaft channel for sewage circulation is provided between adjacent reaction chambers, the top of the vertical shaft channel is connected with the top of the previous reaction chamber, and the bottom of the vertical shaft channel is connected with the bottom of the next reaction chamber.

[0038] In a preferred implementation, the thickness of the filler layer is 2.5 to 3 m.

[0039] In the specific implementation, the hydrolysis acidification tank adopts an above-ground reinforced concrete structure. The influent COD is 2.3g / L, and the designed removal rate is ≥35%. The reactor is divided into 3 compartments, each of which adopts the structure of filter screen on the lower filter plate. The pore size of the upper filter screen is 3mm. The filter material is placed between the lower filter plate and the upper filter screen. The filter material layer thickness is 2.5m, and the total volume is 350m 3 , empty bed contact time 3h. After the hydrolysis acidification tank is in operation, in order to promote the shedding and renewal of the biofilm on the surface of the seasoning, the single hydrolysis acidification tank can be flushed under aeration as needed. The pool uses suspended ceramsite with a particle size of 12-16mm to replace the original elastic three-dimensional filler. The surface of this filler is rough and hydrophilic, and organisms are easy to attach to form biofilms.

[0040] In a preferred embodiment, the packing layer includes a suspended ceramsite layer at the upper layer and an activated carbon packing layer at the lower layer. The particle size of the suspended ceramsite is 12-16 mm; the thickness of the activated carbon packing layer is 50 cm, and the particle size of the activated carbon is 6-8 mm.

[0041] By using a combination of a suspended ceramsite layer on the upper layer and an activated carbon filler layer on the lower layer, the use of activated carbon helps to accelerate the reproduction of microorganisms and promote the COD degradation ability of microorganisms. The synergy of the two is more conducive to sewage treatment and improves the COD degradation amount.

[0042] In a specific implementation, the hydrolysis sedimentation tank 20 adopts an upflow effluent structure, and the hydrolysis sedimentation tank is provided with an inclined tube sedimentation structure 21. The sewage treatment system is heavy, the hydrolysis sedimentation tank, 2, above-ground reinforced concrete structure, upflow effluent, external dimensions of 8.5m×5.6m×8.15m, inclined tube sedimentation, surface load 0.6~1.8m 3 / (m 2 ·h), sedimentation time 1.6h, and an artificial mud outlet is set at the bottom. Adding a sedimentation tank at the end of the hydrolysis acidification tank can further reduce the SS content in the effluent and improve the hydrolysis removal rate.

[0043] In a specific implementation, two membrane grid channels and A / O bio-tanks are set up, each with a scale of 25,000 m 3 / d. Membrane grid mesh aperture 1mm; A / O biological pool total residence time 23.3h, including: anoxic zone 10.2h, aerobic zone 13.1h. Membrane pool to aerobic pool return ratio 200% ~ 400%, aerobic pool to anoxic pool return ratio 200% ~ 400%, aeration volume 5640m 3 / h, gas-water ratio 6:1.

[0044] In a preferred implementation, one ozone contact oxidation pool is set up. The hydraulic retention time is 1 hour; the ozone contact oxidation pool is divided into 2 compartments, and the ozone dosage is 50 mg / L; the ozone in the ozone contact pool is added in three stages, and the contact time of the three stages is 15, 20, and 25 minutes respectively, and the dosage ratio of the three stages is 50%, 30%, and 20%.

[0045] In a preferred implementation, the disinfection tank, pasteurization metering tank and recycled water pump house are built together. The effective contact time of the disinfection tank is 32 minutes, and the throat width of the pasteurization metering tank is 0.75m.

[0046] The sewage treatment system of the utility model also includes a sodium hypochlorite dosing room and a comprehensive dosing room. Among them, one sodium hypochlorite dosing room is set up and built together with the effluent online instrument detection room. 10% sodium hypochlorite stock solution is used for dosing. The average chlorine addition amount is 10mg / L, and the maximum chlorine addition amount is 15mg / L. The dosing point is set at the water inlet well of the contact disinfection pool, and there are two dosing points.

[0047] The comprehensive dosing room is provided with one. Concentrated sulfuric acid and sodium hydroxide are used for pH value adjustment, with 2 dosing points in the inlet regulating tank; ferric chloride is used as coagulant, with 4 dosing points in the coagulation sedimentation tank and 4 dosing points in the biological pool effluent, with a dosing amount of 50 mg / L and a concentration of 5%; PAM is used as coagulant aid, with 4 dosing points in the coagulation sedimentation tank, a dosing amount of 3 mg / L and a concentration of 0.2%; commercially available 58% sodium acetate is used for carbon source addition, with a sodium acetate dosing amount of 330 mg / L, 4 dosing points in the front anoxic zone and the rear anoxic zone, and a dosing concentration of 20%.

[0048] For other structures of the pretreatment device and sewage treatment system described in this embodiment, refer to the prior art.

[0049] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Therefore, any modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A pretreatment device, characterized in that: At least including a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank which are arranged in sequence and connected along the sewage treatment direction; The hydrolysis acidification tank is provided with three reaction chambers connected in sequence, a lower filter plate and an upper filter screen are provided in the middle of each reaction chamber, and a packing layer is provided between the lower filter plate and the upper filter screen; Wherein, a vertical shaft channel for sewage circulation is arranged between adjacent reaction chambers, the top of the vertical shaft channel is communicated with the top of the previous reaction chamber, and the bottom of the vertical shaft channel is communicated with the bottom of the next reaction chamber.

2. A pretreatment device according to claim 1, characterized in that: The thickness of the packing layer is 2.5-3 m.

3. A pretreatment device according to claim 1, characterized in that: The filler layer comprises a suspended ceramsite layer located at an upper layer and an activated carbon filler layer located at a lower layer.

4. A pretreatment device according to claim 3, characterized in that: The particle size of the suspended ceramsite is 12 to 16 mm; the thickness of the activated carbon filler layer is 50 cm, and the particle size of the activated carbon is 6 to 8 mm.

5. A pretreatment device according to any one of claims 1 to 4, characterized in that: There are two coagulation sedimentation tanks, two hydrolysis acidification tanks and two hydrolysis sedimentation tanks.

6. A pretreatment device according to claim 5, characterized in that: The hydrolysis sedimentation tank adopts an upflow water outlet structure, and the hydrolysis sedimentation tank is provided with an inclined tube sedimentation structure.

7. A pretreatment device according to claim 6, characterized in that: The pretreatment device comprises a coarse screen room, a regulating tank, a lifting pump room, a fine screen room, an aerated grit chamber, a coagulation sedimentation tank, a hydrolysis acidification tank and a hydrolysis sedimentation tank which are sequentially arranged and connected along the sewage treatment direction; The pretreatment device also includes an emergency pool, which is connected to the regulating pool.

8. A sewage treatment system, characterized in that: It comprises a pre-treatment device as claimed in claim 7.

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