Kitchen waste wastewater treatment system and treatment process thereof

Abstract

The present application belongs to the technical field of kitchen waste water treatment, and particularly relates to a kitchen waste water treatment system and a treatment process thereof. The system comprises a slurry pool, a three-phase separation unit, an adjusting pool, a gas floatation pool and a biochemical pool which are sequentially connected. The slurry pool is used for mixing the kitchen waste water to be treated with activated sludge. The slurry pool can control odor before the kitchen waste water enters the treatment process, and is convenient for dewatering and separation. The activated sludge can adsorb the oil phase in the slurry after being combined with the kitchen waste water, and the kitchen waste water mixed with the sludge and the first flocculant can further improve the dewatering efficiency. The system can control the odor in the kitchen waste water, and simplifies the treatment process of the kitchen waste water.

Description

[0001] Related Applications

[0002] The application claims priority from the application No. 202111151593.8 filed on November 15, 2021, the title of which is: A kitchen waste wastewater treatment system and its treatment process. TECHNICAL FIELD

[0003] The application relates to the technical field of kitchen waste wastewater treatment, in particular to a kitchen waste wastewater treatment system and its treatment process. BACKGROUND

[0004] The kitchen waste wastewater is a common wastewater, and its annual production is increasing. The kitchen waste wastewater is mainly wastewater generated during the treatment of kitchen waste. If the wastewater is not effectively treated and directly discharged, it will cause serious pollution to natural water bodies and the social environment. The kitchen waste wastewater has the characteristics of high organic matter concentration, high ammonia nitrogen content, high sulfide, etc., and is difficult to treat.

[0005] The existing kitchen waste wastewater treatment system is complex, the equipment investment is large, and the treatment effect is difficult to maintain, which can easily lead to secondary pollution. The existing process discloses a kitchen waste wastewater low-energy consumption treatment process and equipment. The process makes the kitchen waste wastewater enter the water distribution tank, and then mix with the reflux liquid of the aerobic tank, the built-in MBR reflux sludge and the effluent of the high-efficiency denitrification reactor. After mixing, nitrogen is generated, and the water is separated by the top three-phase separator and discharged to the water distribution tank and the anoxic tank.

[0006] However, the existing technology cannot control the odor in the kitchen waste wastewater, and the treatment process is complex. SUMMARY

[0007] Therefore, the technical problem to be solved by the application is to overcome the defects that the existing technology cannot control the odor in the kitchen waste wastewater and the treatment process is complex, so as to provide a kitchen waste wastewater treatment system and its treatment process.

[0008] To this end, the application provides the following technical solutions.

[0009] The application provides a kitchen waste wastewater treatment system, which comprises:

[0010] A slurry pool, a three-phase separation unit, an adjusting pool, a flotation tank and a biochemical tank are sequentially connected.

[0011] The slurry pool is used for mixing the kitchen waste wastewater to be treated with activated sludge.

[0012] Optionally, the kitchen waste wastewater treatment system further comprises a sludge scraping pool connected with the sludge inlet of the slurry pool.

[0013] Optionally, the inlet of the sludge scraping pool is connected with the flotation tank and / or the biochemical tank.

[0014] Optionally, the system further comprises a clean water pool, which is communicated with the biochemical pool.

[0015] Optionally, the biochemical pool is an Engelbart SST biochemical pool.

[0016] Optionally, the biochemical pool is provided with a gas stripping zone, an aeration zone and a clarification zone.

[0017] The gas stripping zone comprises an aeration hose, a gas stripping support, an air inlet pipe, a distributor and a water inlet pipe; the aeration zone comprises an Engelbart aeration pipe, an aeration support, a lifting device, an air inlet pipe and a distributor; and the clarification zone comprises a filler, a filler support, a water outlet pipe and a compartment partition.

[0018] Optionally, the aeration hose is provided by an Engelbart manufacturer and has a model of DN50; and the gas stripping zone, the aeration zone and the clarification zone are all provided in a conventional manner.

[0019] Optionally, the clarification zone is provided with a filler, which is a V-shaped pipe filler provided by an Engelbart manufacturer and has a model of VR / VF. The filler can change the flow state of water from turbulent flow to steady flow by means of a labyrinth multi-channel structure, and meanwhile, a suspended sludge layer is formed. The filler is located in the middle of the clarification zone, the bottom of the filler is about 1.3 meters away from the bottom of the pool, and the top of the filler is lower than the water surface.

[0020] Optionally, the surface of the filler is attached with a microbial film, and the microbial film contains a plurality of microorganisms, such as autotrophic bacteria and heterotrophic bacteria, for example, common denitrifying bacteria and acidophilic bacteria.

[0021] Optionally, the three-phase separation unit is one of a three-phase horizontal screw centrifuge and a three-phase disc separator.

[0022] The application further provides a treatment process for kitchen waste water, which is characterized by comprising the following steps:

[0023] Deodorization: mixing the kitchen waste water to be treated with active sludge to perform deodorization;

[0024] Three-phase separation: mixing the deodorized waste water with a first flocculant to perform three-phase separation to obtain sludge, an oil phase and a water phase;

[0025] Chemical dosing air flotation: mixing the separated water phase with an iron salt flocculant to perform air flotation treatment;

[0026] Biochemical treatment: performing biochemical treatment on the air-flotation-treated waste water.

[0027] Optionally, the ratio of the amount of the kitchen waste water to the amount of the active sludge is 1:1.

[0028] The mixing mode in the deodorization step is stirring mixing.

[0029] Optionally, the activated sludge is domesticated stabilized sludge, which is sludge from a municipal sewage plant, is adjusted and domesticated to become stabilized sludge, is cultured under low-dissolved oxygen conditions, has ammonia nitrogen and total nitrogen in the sludge mixed liquid less than 20 mg / l, has good sludge settling property, and is easy to separate.

[0030] Optionally, the dregs generated in the chemical dosing air flotation step and the sludge generated in the biochemical treatment step are used as activated sludge.

[0031] The first flocculant is at least one of polyacrylamide, polymeric ferric sulfate, and polyaluminum chloride.

[0032] The ferric salt flocculant is at least one of polymeric ferric sulfate, ferric chloride, and ferric sulfate.

[0033] Optionally, the addition amount of the first flocculant is determined according to the water quality, water quantity, and solid content, and the addition amount of the ferric salt flocculant is a conventional flocculant addition amount.

[0034] Optionally, the method further comprises a step of adding a disinfectant to the wastewater after biochemical treatment.

[0035] Optionally, the disinfectant is at least one of sodium hypochlorite, liquid chlorine, and chlorine dioxide. In actual application, the disinfectant is usually sodium hypochlorite because liquid chlorine is highly toxic and chlorine dioxide needs to be prepared on site.

[0036] Optionally, the biochemical treatment comprises air stripping, aeration, and sedimentation steps.

[0037] In the air stripping step, air provided by a fan enters an air distributor through an air inlet pipe, is then distributed to an aeration hose, and is lifted by air thrust to form a reflux in the biochemical tank.

[0038] In the aeration step, a blanket aeration is adopted, air provided by a fan enters an air distributor through an air inlet pipe, is then distributed to an aeration hose, the aeration hose is distributed in a long strip, an Engebai proprietary aeration pipe is adopted, general oxygen mass transfer is 20%-30%, the Engebai aeration pipe can achieve 40%-50%, power consumption of the fan is saved by at least 30%, and the aeration pipe is easy to maintain and can be maintained by large flux or chemical cleaning.

[0039] In the sedimentation step, the process adopts an internal clarification zone, after biochemical treatment in the whole tank, the wastewater flows into the clarification zone by itself, is further treated by microorganisms on the surface of the filler, and sludge is settled and clarified to produce effluent.

[0040] Optionally, the kitchen waste wastewater treatment process provided by the present application adopts the kitchen waste wastewater treatment system provided by the present application.

[0041] The technical scheme of the present application has the following advantages:

[0042] 1. The kitchen waste wastewater treatment system provided by the present application comprises a slurry pool, a three-phase separation unit, an adjusting pool, a flotation pool and a biochemical pool which are sequentially connected, wherein the slurry pool is used for mixing the kitchen waste wastewater to be treated and activated sludge. The slurry pool can control odor before the kitchen waste wastewater enters the treatment process, and is convenient for dewatering and separation. After the activated sludge is combined with the kitchen waste wastewater, the oil phase in the slurry can be adsorbed, and the dewatering efficiency can be further improved after the kitchen waste wastewater is mixed with the sludge and the first flocculant.

[0043] 2. In the kitchen waste wastewater treatment system provided by the present application, the mixed solution from the slurry pool is separated by the three-phase separation unit to separate the water phase, sludge and oil phase in the wastewater, so that the separation efficiency is greatly improved after the activated sludge floc is mixed.

[0044] 3. The present application is provided with an Engbay synchronous nitrification and denitrification biochemical pool. An Engbay aeration pipe is arranged in the gas stripping area of the biochemical pool, so that the reflux ratio effect of tens of times of plug flow can be achieved. A blanket type aeration support, an Engbay aeration pipe, an air distributor, an air inlet pipe and a lifting device are arranged in the aeration area of the biochemical pool, so that uniform aeration of the whole pool can be achieved. Through the lifting device of the blanket type aeration, the damaged aeration pipe at the bottom of the pool is lifted to the top of the pool by simple manpower, and then pulled to the bottom of the pool after replacement, so that the effect of replacing the aeration pipe without cleaning the pool can be achieved. The filler is arranged in the clarification area, so that the water can be uniformly distributed, the upward flow velocity can be fast, and the water production capacity can be large. The surface of the filler is attached with a microbial film, so that the biochemical effluent can be rapidly settled and clarified.

[0045] 4. The wastewater treatment process of the kitchen waste wastewater treatment system provided by the present application comprises the following steps: deodorization: mixing the kitchen waste wastewater to be treated and activated sludge to deodorize; three-phase separation: mixing the wastewater after deodorization and a first flocculant to perform three-phase separation, so as to obtain sludge, an oil phase and a water phase; air flotation: mixing the water phase obtained by separation and an iron salt flocculant to perform air flotation treatment; biochemical treatment: performing biochemical treatment on the wastewater after air flotation. Compared with the traditional treatment process of kitchen waste wastewater, the kitchen waste wastewater can be treated only by these steps, the traditional treatment process of kitchen waste wastewater is simplified, and the odor of the mixed kitchen waste wastewater is controlled.

[0046] 5. The process makes the sludge floc more strong in coagulation and the sludge dewatering efficiency is high by adding the first flocculant in the three-phase separation process; the iron salt flocculant is added in the deodorization process and the chemical dosing air flotation process, so that the whole process can also carry out the turbidity removal, decolorization, deoiling, dewatering, bacteria removal, deodorization, algae removal, removal of COD, BOD and heavy metal ions in water and the like in the process of air flotation. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the drawings needed to be used in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0048] Figure 1 is a kitchen waste wastewater treatment system in embodiment 1 of the present application;

[0049] Reference signs:

[0050] 1 - slurry pool; 11 - water inlet; 12 - water outlet; 13 - sludge inlet; 2 - slag pool; 3 - adjusting pool; 4 - three-phase separation unit; 5 - air flotation pool; 6 - biochemical pool; 7 - clean water pool. DETAILED DESCRIPTION

[0051] The following examples are provided to better further understand the present application and are not limited to the best mode, and do not constitute a limitation on the content and protection scope of the present application. Any person under the inspiration of the present application or the combination of the present application with other prior art features can obtain any product same or similar to the present application, which falls within the protection scope of the present application.

[0052] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0053] Embodiment 1

[0054] The present embodiment provides a kitchen waste wastewater treatment system, as shown in Figure 1 The present embodiment provides a kitchen waste wastewater treatment system, as shown in

[0055] The slurry tank is provided with a water inlet 11, a water outlet 12, and a sludge inlet 13. The water inlet 11 is used to allow the kitchen waste water to be treated to enter the slurry tank, the water outlet 12 is used to allow the kitchen waste water mixed with the activated sludge to be discharged into the three-phase separation unit 4, and the sludge inlet 13 is used to allow the activated sludge in the sludge scraping tank 1 to be discharged into the slurry tank 1. In the slurry tank 1, the kitchen waste water is fully mixed with the activated sludge, so that the odor in the kitchen waste water can be removed, and the oil phase in the waste water can be adsorbed.

[0056] The three-phase separation unit 4 can adopt one of a three-phase horizontal screw centrifuge and a three-phase disc separator. In the embodiment, the three-phase horizontal screw centrifuge is provided by Shanghai Tongchen Environmental Protection Co., Ltd. The inlet of the three-phase separation unit 4 is connected with the water outlet 12 of the slurry tank. By providing the three-phase separation unit 4, the mixed liquid from the slurry tank 1 can be separated into water phase, sludge, and oil phase.

[0057] The inlet of the adjusting tank 3 is connected with the liquid phase outlet of the three-phase separation unit 4. The adjusting tank 3 is used to temporarily store the liquid phase discharged from the three-phase separation unit 4.

[0058] The inlet of the air flotation tank 5 is connected with the outlet of the adjusting tank 3, and the air flotation process adopted in the air flotation tank 5 is one of electrolytic flotation, aeration flotation, and dissolved air flotation. In the embodiment, the aeration flotation is adopted, and the air flotation tank 5 is provided with a sludge scraping plate at the top. By the air flotation, the suspended solids and colloidal substances can be further removed, and the sludge scraping plate scrapes the floating sludge into the sludge scraping tank 2.

[0059] The inlet of the biochemical tank 6 is connected with the outlet of the air flotation tank 5, and the biochemical tank 6 is internally provided with a gas lifting zone, an aeration zone, and a clarification zone. The gas lifting zone provided in the biochemical tank 6 includes an aeration hose and a gas lifting support. The aeration hose can achieve a reflux ratio effect of tens of times by the gas push flow technology, and the gas lifting support can fix the aeration hose to stabilize the aeration state and uniformly aerate the gas lifting zone. The aeration zone provided in the biochemical tank 6 includes a blanket aeration support, an aeration hose, an air distributor, an air inlet pipe, and a lifting device. The aeration hose can achieve large flux and low dissolved oxygen aeration with an oxygen mass transfer efficiency of 50%, the blanket aeration support can avoid the aeration hose from being knotted and swinging at the bottom of the tank to affect the aeration effect, and the lifting device can realize the replacement of the aeration hose without cleaning the tank and stopping the water, which is more convenient for maintenance. The clarification zone provided in the biochemical tank 6 includes fillers, a filler support, and a partitioning partition. The fillers can uniformly distribute water, quickly rise, and produce large amount of water, and the partitioning partition can separate the water. The surface of the fillers is attached with a microbial film, which can make the biochemical effluent quickly settle and be clarified and separated.

[0060] The slag scraping pool 2 of the system is also communicated with the biochemical pool 6, and the outlet of the slag scraping pool 2 is connected with the sludge inlet 13 of the sludge pool 1. The slag scraping pool 2 discharges the floating slag in the air flotation pool 5 and the residual activated sludge in the biochemical pool 6 into the sludge pool 1, so that the wastewater in the sludge pool 1 is fully mixed with the activated sludge, and the mixing mode is stirring mixing.

[0061] In some alternative embodiments, the system further comprises a clean water pool 7, and the inlet of the clean water pool 7 is connected with the outlet of the biochemical pool 6. The clean water pool 7 stores the effluent of the biochemical pool 7 and discharges the effluent after reaching the standard, and the standard is that the effluent can reach the first A discharge standard at most.

[0062] Embodiment 2

[0063] The embodiment provides a kitchen waste wastewater treatment process, and the system provided in the embodiment 1 is used, and the specific process is as follows:

[0064] First, the kitchen waste wastewater to be treated is discharged into the sludge pool 1 through the water inlet 11 of the sludge pool 1. In the initial stage of the process, municipal sludge needs to be added, and after the system is stably operated, the floating slag generated by the air flotation pool 5 and the sludge generated by the biochemical pool 6 can meet the use demand of the activated sludge in the deodorization stage; every cubic meter of kitchen waste wastewater in the sludge pool 1 is fully mixed with every cubic meter of activated sludge (stabilized sludge generated after domestication of sludge of a municipal sewage plant) by stirring.

[0065] The mixed liquid is discharged into a three-phase horizontal screw centrifuge through the water outlet 12 of the sludge pool 1, mixed with 1 mg (per ton of water) of polyacrylamide, three-phase separation is performed at a separation rate of 12 kg-DS / h, the oil phase and the sludge separated are discharged, and the water phase flows into the adjusting pool 3 through the overflow pipe, and the adjusting pool 3 temporarily stores the water phase after three-phase separation.

[0066] The water in the adjusting pool 3 enters the air flotation pool 5 through the lifting pump, 5L of polymeric ferric sulfate solution with a content of 12% is added per ton of water, and suspended substances and colloidal substances are further removed, the floating slag generated by air flotation is scraped to the slag scraping pool 2 by the slag scraping plate, and the wastewater after air flotation flows into the air stripping area of the biochemical pool 6. The gas introduced into the air flotation pool 5 is air, and the gas amount is 0.1 m 3 / h, and the biochemical pool 6 is an Engbay simultaneous nitrification and denitrification biochemical pool.

[0067] The wastewater entering the gas stripping zone of the biochemical tank 6 is continuously stripped into the aeration zone by gas stripping. The gas stripping zone is provided with an aeration pipe through which air is introduced into the gas stripping zone at a rate of 200 L / min. The wastewater is subjected to simultaneous nitrification and denitrification in the aeration zone. The aeration zone is provided with a blanket aeration system. The aeration pipe is provided with eight groups of aeration pipes, a total of two groups. Air is introduced into the aeration zone through the distributor and the aeration pipe at an aeration rate of 500 L / min. The sludge concentration in the aeration zone is 8000 mg / L. The wastewater stays in the biochemical tank 6 for 13 days. The backflow is more than 100 times. The sludge age is more than 30 days. The biochemical effluent is settled in the clarification zone. The fillers in the clarification zone can make the sludge settle rapidly. The settling time is one hour. The sludge and water are separated. The residual sludge is lifted by a pump into the sludge scraping tank 2. The obtained effluent flows into the clear water tank 7. Then, 0.12 kg of sodium hypochlorite is added.

[0068] The sludge mixture in the sludge scraping tank 2 flows into the slurry tank 1 by itself under the power of the liquid level difference through the sludge inlet 13.

[0069] Example 3

[0070] The present embodiment provides a kitchen waste wastewater treatment process. The system provided in Example 1 is used. The specific process is as follows:

[0071] First, the kitchen waste wastewater to be treated is discharged into the slurry tank 1 through the water inlet 11 of the slurry tank 1. In the initial stage of the process, active sludge needs to be added. After the system is stably operated, the sludge produced by the air flotation tank 5 and the sludge produced by the biochemical tank 6 can meet the use demand of active sludge in the deodorization stage. Each cubic meter of kitchen waste wastewater in the slurry tank 1 is mixed with each cubic meter of active sludge (stabilized sludge produced after domestic sewage plant sludge is domesticated).

[0072] The mixed liquid is discharged into the feed inlet of the stacked screw separator through the water outlet 12 of the slurry tank 1 and mixed with 1 mg (per ton of water) of polyaluminum chloride. The separation rate is 6 kg-DS / h for three-phase separation. The oil tank and sludge obtained by separation are discharged. The water phase flows into the adjusting tank 3 through the overflow pipe. The adjusting tank 3 temporarily stores the water phase after three-phase separation.

[0073] The water in the adjusting tank 3 enters the air flotation tank 5 through the lifting pump. 4 kg of polyaluminum chloride is added per ton of water to further remove suspended substances and colloidal substances. The sludge produced by air flotation is scraped into the sludge scraping tank 2 by the sludge scraping plate. The wastewater after air flotation flows into the gas stripping zone of the biochemical tank 6 by itself. The gas introduced into the air flotation tank 5 is air. The gas introduction rate is 0.1 m 3 / h. The biochemical tank 6 is an Engbay simultaneous nitrification and denitrification biochemical tank.

[0074] The wastewater entering the gas stripping zone of the biochemical tank 6 is continuously stripped into the aeration zone by gas stripping. The gas stripping zone is provided with an aeration pipe through which air is introduced into the gas stripping zone. The gas stripping rate is 200 L / min. The wastewater in the aeration zone is subjected to simultaneous nitrification and denitrification. The aeration zone is provided with a blanket aeration system. The aeration pipe is provided with eight groups of aeration pipes, a total of two groups. Air is introduced into the aeration zone through the distributor and the aeration pipe. The aeration rate is 500 L / min. The sludge concentration in the aeration zone is 8000 mg / L. The wastewater stays in the biochemical tank 6 for 13 days. The reflux is more than 100 times. The sludge age is more than 30 days. The biochemical effluent is settled in the clarification zone. The filler in the clarification zone can make the sludge settle rapidly. The settling time is one hour. The sludge and water are separated. The residual sludge is lifted by a pump into the sludge scraping tank 2. The obtained effluent flows into the clear water tank 7. Then, 0.12 kg of sodium hypochlorite is added.

[0075] The sludge mixture in the sludge scraping tank 2 flows into the slurry tank 1 by itself under the power of the liquid level difference through the sludge inlet 13.

[0076] Comparative Example 1

[0077] This comparative example provides a kitchen waste wastewater treatment process. The system provided in Example 1 is used. The specific process is as follows:

[0078] The kitchen waste wastewater to be treated is first discharged into the slurry tank 1 through the water inlet 11 of the slurry tank 1. The kitchen waste wastewater is discharged into the three-phase horizontal screw centrifuge through the water outlet 12 of the slurry tank 1 and mixed with 1 mg (per ton of water) of polyacrylamide. The separation rate is 12 kg-DS / h for three-phase separation. The oil phase and sludge obtained by separation are discharged. The water phase flows into the adjusting tank 3 through the overflow pipe. The adjusting tank 3 serves as a temporary storage for the water phase after three-phase separation.

[0079] The water in the adjusting tank 3 enters the air flotation tank 5 through a lifting pump. 5 L of 12% polymeric ferric sulfate is added per ton of water to further remove suspended and colloidal substances. The scum generated by air flotation is scraped into the sludge scraping tank 2 by a scraping plate. The wastewater after air flotation flows into the gas stripping zone of the biochemical tank 6 by itself. The gas introduced into the air flotation tank 5 is air. The gas volume is 0.1 m 3 / h. The biochemical tank 6 is an Engbay simultaneous nitrification and denitrification biochemical tank.

[0080] The wastewater entering the gas stripping zone of the biochemical tank 6 is continuously stripped into the aeration zone by gas stripping. The gas stripping zone is provided with an aeration pipe through which air is introduced into the gas stripping zone at a rate of 200 L / min. The wastewater in the aeration zone is subjected to simultaneous nitrification and denitrification. The aeration zone is provided with a blanket aeration system. The aeration pipe is provided with eight groups of aeration pipes, a total of two groups. Air is introduced into the aeration zone through the distributor and the aeration pipe at an aeration rate of 500 L / min. The sludge concentration in the aeration zone is 8000 mg / L. The wastewater stays in the biochemical tank 6 for 13 days. The reflux is more than 100 times. The sludge age is more than 30 days. The biochemical effluent is settled in the clarification zone for sludge-water separation. The excess sludge is lifted by a pump into the sludge scraping tank 2. The obtained effluent flows into the clear water tank 7, and then 0.12 kg of sodium hypochlorite is added.

[0081] The sludge mixture in the sludge scraping tank 2 flows into the slurry tank 1 through the sludge inlet 13 under the power of the liquid level difference.

[0082] Evaluation: Examples 2-3 and Comparative Example 1 were evaluated. The source of the kitchen wastewater

[0083] The method for evaluating odor is to use olfactory evaluation or use a gas chromatograph to use high-speed ion impact gaseous molecules to achieve qualitative and structural analysis. By comparing the data of Examples 2 and Comparative Example 1, it is found that the deodorization by activated sludge mixing with water can effectively control odor.

[0084] The method for evaluating the treatment effect is:

[0085] First, the wastewater to be treated in Examples 2-3 and Comparative Example 1 was detected by the inlet water data. It was found that the organic matter concentration of the raw water was greater than 10000 mg / L, the total nitrogen concentration was greater than 2000 mg / L, and the ammonia nitrogen concentration was greater than 350 mg / L.

[0086] Then the effluent was detected by a professional testing agency. The test results are shown in Table 1

[0087] Table 1:

[0088]

[0089] As can be seen from Table 1, the reflux sludge lifting treatment effect has adsorption effect, reduces odor, and helps solid-liquid separation effect, neutralizes the acidity of the incoming water, and greatly improves the effluent effect.

[0090] Obviously, the above embodiments are merely example for clearly illustrating but not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments need not and can not be enumerated. The obvious changes or variations derived from the above description are still within the protection scope of the present application.

Claims

1. A process for treating kitchen waste wastewater, characterized in that, The treatment system comprises a slurry tank, a three-phase separation unit, an equalization tank, an dissolved air flotation tank, and a biological treatment tank, all connected in sequence. The slurry tank is used to mix the kitchen waste wastewater to be treated with activated sludge. The biochemical tank is equipped with an air extraction zone, an aeration zone, and a clarification zone. The air-lift zone includes an aeration hose, an air-lift support, an air inlet pipe, a distributor, and a water inlet pipe; the aeration zone includes an Engelbe aeration pipe, a blanket aeration support, a lifting device, an air inlet pipe, and a distributor; the clarification zone includes packing material, a packing material support, a water outlet pipe, and a compartment partition. The clarification zone is equipped with packing material, which is inclined tube packing. The activated sludge is stabilized sludge; The processing technology includes the following steps: Deodorization: The wastewater from the kitchen waste to be treated is mixed with activated sludge in a slurry tank for deodorization; Three-phase separation: The deodorized wastewater is mixed with the first flocculant in the three-phase separation unit and three-phase separation is carried out to obtain sludge, oil phase and water phase; Chemical flotation: The separated aqueous phase is mixed with iron salt flocculant in a flotation tank for flotation treatment; Biological treatment: The wastewater after air flotation is subjected to biological treatment in a biological treatment tank.

2. The kitchen waste wastewater treatment process according to claim 1, characterized in that, It also includes a sludge scraper connected to the sludge inlet of the slurry tank.

3. The kitchen waste wastewater treatment process according to claim 2, characterized in that, The inlet of the sludge scraping tank is connected to the air flotation tank and the biochemical tank.

4. The food waste wastewater treatment process according to any one of claims 1-3, characterized in that, It also includes a clear water pool, which is connected to the biochemical pool.

5. The kitchen waste wastewater treatment process according to claim 4, characterized in that, The biological treatment tank is an Engelby simultaneous nitrification-denitrification biological treatment tank.

6. The kitchen waste wastewater treatment process according to claim 5, characterized in that, The biochemical tank is equipped with an air extraction zone, an aeration zone, and a clarification zone.

7. The kitchen waste wastewater treatment process according to claim 6, characterized in that, The clarification zone is equipped with packing material.

8. The kitchen waste wastewater treatment process according to claim 7, characterized in that, The surface of the packing material is covered with a microbial film with a thickness of 0.5-2 mm.

9. The kitchen waste wastewater treatment process according to claim 1, characterized in that, The three-phase separation unit is one of a three-phase horizontal screw centrifuge or a three-phase disc separator.

10. The treatment process for kitchen waste wastewater according to claim 1, characterized in that, The ratio of kitchen waste wastewater to activated sludge is 1:

1.

11. The treatment process for kitchen waste wastewater according to claim 1, characterized in that, The sludge scraped from the chemical flotation step and the sludge from the biochemical treatment step are recycled back to the deodorization step as activated sludge.

12. The treatment process for kitchen waste wastewater according to claim 1, characterized in that, The first flocculant is at least one of polyacrylamide, polyferric sulfate, and polyaluminum chloride; The iron salt flocculant is at least one of polyferric sulfate, ferric chloride, and ferric sulfate.

13. The treatment process for kitchen waste wastewater according to claim 1, characterized in that, It also includes the step of adding disinfectant to the biochemically treated wastewater; Optionally, the disinfectant is at least one of sodium hypochlorite, liquid chlorine, and chlorine dioxide.

14. The treatment process for kitchen waste wastewater according to claim 1, characterized in that, The biochemical treatment includes airlift, aeration, and sedimentation steps.

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