Pretreatment device for kitchen waste sewage
By designing a food waste sewage pretreatment device integrating acid-base adjustment, two-phase decanter centrifuge and flocculation treatment, the problem of high ammonia nitrogen concentration in wastewater during food waste treatment was solved and effective wastewater pretreatment was achieved. Treatment and reduction of COD and SS reduce carbon source requirements in subsequent treatment processes.
Patent Information
- Application Number
- CN202421249052.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-03
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2034-06-03
AI Technical Summary
During the treatment of kitchen waste, the concentration of ammonia nitrogen in the wastewater is extremely high, which can easily lead to excessive ammonia nitrogen and nitrite poisoning. It is difficult to deal with and requires additional carbon sources.
A pretreatment device for food waste sewage is designed, including a wastewater storage and transportation mechanism, an acid-base adjustment tank, a lime milk mechanism, a two-phase decanter centrifuge, a flocculation adjustment tank, a PAM and PAC addition mechanism, an aeration mechanism, etc. , through the synergistic effect of these components, solids and insoluble impurities in wastewater are removed, the PH value is adjusted, and wastewater pretreatment is achieved.
Effectively remove solids and insoluble impurities in wastewater, reduce COD and SS concentrations, stabilize PH value, reduce the risk of excessive ammonia nitrogen and nitrite poisoning, improve sewage treatment effects, and reduce carbon source requirements in subsequent treatment processes.
Smart Images
Figure CN222374540U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of restaurant kitchen waste treatment, in particular to a pretreatment device for restaurant kitchen waste sewage. Background Art
[0002] Restaurant kitchen waste is the most common waste generated in daily urban life, and it has been increasing year by year. With the promotion of the classification of urban domestic waste, more and more cities are separating restaurant kitchen waste and kitchen waste from domestic waste for separate treatment. Restaurant kitchen waste has the characteristics of high oil content, high water content, strong odor, and easy corruption, which makes it difficult to treat as a resource. In particular, the wastewater generated in the process of restaurant kitchen waste treatment is highly concentrated organic wastewater, which is more difficult to treat.
[0003] At present, the mainstream process technology used for the treatment of food waste is "pretreatment + oil-water treatment + anaerobic treatment + sewage treatment". After the food waste is collected, it is first pretreated to remove the inorganic part of the waste. Then the slurry part of the waste is heated for three-phase separation to extract most of the oil and fat and separate some solids in the slurry. The wastewater after the separation of oil and solids enters the anaerobic mechanism for biochemical treatment. After removing most of the COD and SS, it enters the sewage treatment mechanism and further reduces the COD and SS through membrane treatment until the discharge meets the standards.
[0004] The animal and plant fats and SS content of food waste wastewater is still relatively high, with SS generally above 80,000 mg / L and animal and plant fats generally above 3,000 mg / L, which can easily clog the membrane of the sewage treatment mechanism and affect the treatment effect of sewage. Since the COD content of wastewater after the separation of grease and solids from food waste is generally above 100,000 mg / L, the wastewater needs a long residence time in the biochemical treatment mechanism, and it is very easy to have problems of excessive total nitrogen and total phosphorus during the treatment process. While carbon-containing organic matter is removed to the greatest extent, nitrogen-containing organic matter will be converted into ammonia nitrogen and discharged. Therefore, the wastewater after anaerobic digestion contains extremely high ammonia nitrogen concentration, usually at 3,000 mg / L, while COD is only 10,000 mg / L. Wastewater with a serious imbalance in carbon-nitrogen ratio is prone to excessive ammonia nitrogen, nitrite poisoning and other phenomena in the subsequent biochemical treatment process, which is extremely difficult to treat and requires additional carbon sources.
[0005] In view of the above problems, a pretreatment device for kitchen waste sewage is proposed. Utility Model Content
[0006] The purpose of the utility model is to provide a pretreatment device for restaurant kitchen waste sewage, which solves the problem that excessive ammonia nitrogen and nitrite poisoning are easily occurred in the treatment process in the background technology, the treatment is extremely difficult, and an additional carbon source needs to be added.
[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a pretreatment device for kitchen waste sewage, comprising a wastewater storage and conveying mechanism, an acid-base regulating tank is arranged on the right side of the wastewater storage and conveying mechanism, a lime milk mechanism is arranged outside the acid-base regulating tank, a centrifuge feeding mechanism is arranged on the right side of the acid-base regulating tank, a two-phase horizontal screw centrifuge is arranged on the right side of the centrifuge feeding mechanism, a flocculation regulating tank is arranged on the right side of the two-phase horizontal screw centrifuge, a PAM adding mechanism and a PAC adding mechanism are arranged outside the flocculation regulating tank, a wastewater conveying mechanism is arranged on the right side of the flocculation regulating tank, an aeration mechanism is arranged on the right side of the wastewater conveying mechanism, a debris reflux mechanism is arranged on the right side of the aeration mechanism, the other end of the debris reflux mechanism is connected to the wastewater storage and conveying mechanism, a sewage conveying mechanism is arranged on the outside of the aeration mechanism, a heating coil is connected to the right side of the sewage conveying mechanism, a heat exchanger is connected to the right side of the heating coil, a cooling tower is arranged on the outside of the heat exchanger, and a circulation mechanism is arranged on the outside of the cooling tower.
[0008] By adopting the above technical solution, the centrifuge feeding mechanism is connected to the acid-base regulating tank and the two-phase horizontal screw centrifuge through a pipeline, and the other end of the two-phase horizontal screw centrifuge is connected to the flocculation regulating tank through a connecting pipeline.
[0009] As a further description of the above technical solution: the wastewater storage and transportation mechanism includes a storage tank, a water pipe and a wastewater pump body. The wastewater pump body is arranged in the storage tank, and the other end of the wastewater pump body is connected to the water pipe, and the other end of the water pipe is arranged in the acid-base adjustment tank.
[0010] By adopting the above technical solution, wastewater can be collected and transported through the wastewater storage and transportation mechanism.
[0011] As a further description of the above technical solution: the lime milk mechanism includes a shell, a lime milk motor, a lime milk stirring roller, a lime milk connecting pipe and a lime milk pump body. The outside of the shell is fixedly connected to the lime milk motor, the output end of the lime milk motor passes through the shell and is fixedly connected to the lime milk stirring roller, the outside of the shell is provided with a lime milk pump body, both ends of the lime milk pump body are connected to lime milk connecting pipes, one end of the lime milk connecting pipe is connected to the shell, and the other end is connected to the acid-base regulating tank.
[0012] By adopting the above technical solution, the pH value of the wastewater is adjusted by adding lime milk, which has low cost and good effect, and the insoluble impurities can be removed by a two-phase horizontal screw centrifuge.
[0013] As a further description of the above technical solution: the PAM adding mechanism includes a box body, a PAM stirring roller, a PAM connecting pipe and a PAM pump body, the box body is provided with a PAM stirring roller, the outside of the box body is fixedly connected to a PAM connecting pipe, the other end of the PAM connecting pipe is connected to the PAM pump body, the output end of the PAM pump body is connected to the PAM connecting pipe, and the other end of the PAM connecting pipe is arranged in a flocculation adjustment tank.
[0014] By adopting the above technical solution, the PAM stirring roller is driven by an external motor to stir in the box.
[0015] As a further description of the above technical solution: the PAC adding mechanism includes a shell, a PAC stirring roller, a PAC connecting pipe and a PAC pump body, the shell is provided with a PAC stirring roller, the shell is fixedly connected to a PAC connecting pipe on the outside, the other end of the PAC connecting pipe is connected to the PAC pump body, the output end of the PAC pump body is connected to the PAC connecting pipe, and the other end of the PAC connecting pipe is arranged in a flocculation adjustment tank.
[0016] By adopting the above technical solution, the PAC adding mechanism adds 6-8kg / m 3 After adding PAC, add 0.02-0.55kg / m 3 The wastewater showed a flocculation and sedimentation state.
[0017] As a further description of the above technical solution: the wastewater conveying mechanism includes a wastewater connecting pipe and a conveying pump body, the output end of the conveying pump body is connected to a conveying pipe, and the other end of the conveying pipe is arranged in the aeration mechanism.
[0018] By adopting the above technical solution, the wastewater is pumped into the aeration mechanism through the wastewater conveying mechanism.
[0019] As a further description of the above technical solution: the sewage conveying mechanism includes a sewage pump body and a sewage pipe, the sewage pump output end is fixedly connected to the sewage pipe, and the other end of the sewage pipe is connected to the heating coil.
[0020] By adopting the above technical solution, the sewage pump body transports the wastewater from which part of grease and solids have been removed through heating three-phase separation to the heating coil.
[0021] As a further description of the above technical solution: the debris reflux mechanism includes a debris pump body and a debris pipe, the output end of the debris pump body is fixedly connected to the debris pipe, and the other end of the debris pipe is arranged in the wastewater storage and transportation mechanism.
[0022] By adopting the above technical solution, the scum in the wastewater is skimmed off by the skimming mechanism at the top and mixed with the sludge at the bottom, and then discharged to the wastewater storage and transportation mechanism of the solid removal unit by the debris return mechanism.
[0023] Compared with the prior art, the beneficial effects of the utility model are as follows:
[0024] 1. The utility model provides a pretreatment device for restaurant kitchen waste sewage, which first removes solids in wastewater through a two-phase horizontal screw centrifuge, which is stable, reliable and has a guaranteed removal rate; the pH value of the wastewater is adjusted by adding lime milk, which has low cost and good effect, and insoluble impurities can be removed by the two-phase horizontal screw centrifuge.
[0025] 2. The utility model provides a pretreatment device for restaurant kitchen waste sewage, which recovers heat and regulates the temperature of wastewater that has been treated by heating three-phase separation through heat recovery and temperature regulation. The recovered heat is used to preheat the wastewater before heating, thereby reducing steam consumption and reducing the amount of wastewater generated. The wastewater is cooled to below 38°C, making it convenient to enter the anaerobic reactor for biochemical treatment, thereby ensuring the effect of the biochemical treatment. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a schematic diagram of the overall structure of the utility model.
[0027] In the figure: 1. Wastewater storage and transportation mechanism; 2. Lime milk mechanism; 3. Acid-base adjustment tank; 4. Two-phase horizontal screw centrifuge; 5. Flocculation adjustment tank; 6. PAC adding mechanism; 7. PAM adding mechanism; 8. Aeration mechanism; 9. Debris reflux mechanism; 10. Sewage transportation mechanism; 11. Heat exchanger; 12. Circulation mechanism; 13. Cooling tower; 14. Heating coil; 15. Wastewater transportation mechanism; 16. Centrifuge feeding mechanism. DETAILED DESCRIPTION
[0028] The following will refer to the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0029] In order to further understand the content of the utility model, the utility model is described in detail with reference to the accompanying drawings.
[0030] Reference Figure 1The utility model is a pretreatment device for kitchen waste sewage, comprising a wastewater storage and conveying mechanism 1, an acid-base regulating tank 3 is arranged on the right side of the wastewater storage and conveying mechanism 1, for storing wastewater, a lime milk mechanism 2 is arranged outside the acid-base regulating tank 3, a centrifuge feeding mechanism 16 is arranged on the right side of the acid-base regulating tank 3, a two-phase horizontal screw centrifuge 4 is arranged on the right side of the centrifuge feeding mechanism 16, a flocculation regulating tank 5 is arranged on the right side of the two-phase horizontal screw centrifuge 4, a PAM adding mechanism 7 and a PAC adding mechanism 6 are arranged outside the flocculation regulating tank 5, and a wastewater conveying mechanism is arranged on the right side of the flocculation regulating tank 5 15. An aeration mechanism 8 is arranged on the right side of the wastewater conveying mechanism 15. A debris reflux mechanism 9 is arranged on the right side of the aeration mechanism 8, which can reflux impurities and re-filter them. The other end of the debris reflux mechanism 9 is connected to the wastewater storage and conveying mechanism 1. A sewage conveying mechanism 10 is arranged on the outside of the aeration mechanism 8. A heating coil 14 is connected to the right side of the sewage conveying mechanism 10 to achieve a heating effect. A heat exchanger 11 is connected to the right side of the heating coil 14. A cooling tower 13 is arranged on the outside of the heat exchanger 11. A circulation mechanism 12 is arranged on the outside of the cooling tower 13. The circulation mechanism 12 can circulate cooling water.
[0031] Reference Figure 1 The wastewater storage and transportation mechanism 1 includes a storage tank, a water pipe and a wastewater pump body. The wastewater pump body is arranged in the storage tank, and the other end of the wastewater pump body is connected to the water pipe, and the other end of the water pipe is arranged in the acid-base regulating tank 3. The lime milk mechanism 2 includes a shell, a lime milk motor, a lime milk stirring roller, a lime milk connecting pipe and a lime milk pump body. The outside of the shell is fixedly connected to the lime milk motor, and the output end of the lime milk motor passes through the shell and is fixedly connected to the lime milk stirring roller. The outside of the shell is provided with a lime milk pump body, and both ends of the lime milk pump body are connected to the lime milk connecting pipes, one end of the lime milk connecting pipe is connected to the shell, and the other end is connected to the acid-base regulating tank 3. The pH value of the wastewater is adjusted by adding lime milk, which has low cost and good effect, and the insoluble impurities can be removed by the two-phase horizontal screw centrifuge 4.
[0032] Reference Figure 1The PAM adding mechanism 7 includes a box body, a PAM stirring roller, a PAM connecting pipe and a PAM pump body. The box body is provided with a PAM stirring roller, and the outside of the box body is fixedly connected to a PAM connecting pipe. The other end of the PAM connecting pipe is connected to the PAM pump body, and the additive can be extracted through the PAM pump body. The output end of the PAM pump body is connected to the PAM connecting pipe to achieve a conveying effect. The other end of the PAM connecting pipe is arranged in the flocculation regulating tank 5. The PAC adding mechanism 6 includes a shell, a PAC stirring roller, a PAC connecting pipe and a PAC pump body. The shell body is provided with a PAC stirring roller, and the outside of the shell body is fixedly connected to a PAC connecting pipe. The other end of the PAC connecting pipe is connected to the PAC pump body. The output end of the AC pump body is connected to a PAC connecting pipe, and the PAC pump body extracts the additives from the shell. The other end of the PAC connecting pipe is arranged in the flocculation adjustment tank 5. The wastewater conveying mechanism 15 includes a wastewater connecting pipe and a conveying pump body. The output end of the conveying pump body is connected to a conveying pipe, and the other end of the conveying pipe is arranged in the aeration mechanism 8. Oxygen is introduced into the wastewater through the aeration mechanism 8. The sewage conveying mechanism 10 includes a sewage pump body and a sewage pipe. The output end of the sewage pump is fixedly connected to the sewage pipe, and the other end of the sewage pipe is connected to the heating coil 14. The debris reflux mechanism 9 includes a debris pump body and a debris pipe. The output end of the debris pump body is fixedly connected to the debris pipe, and the other end of the debris pipe is arranged in the wastewater storage and conveying mechanism 1.
[0033] Working principle: The wastewater storage and conveying mechanism 1 conveys the wastewater that has been heated and three-phase separated to remove part of the oil and solids to the acid-base regulating tank 3, and mixes it with the lime milk added by the lime milk mechanism 2 in the acid-base regulating tank, and the pH value of the wastewater is adjusted from 3-5 to 7-9. The wastewater with adjusted pH value is fed to the two-phase horizontal screw centrifuge 4 by the centrifuge feeding mechanism 16. The centrifuge feeding mechanism 16 is equipped with flow control. The solids in the wastewater are pre-removed through the feed flow control and the parameter adjustment of the two-phase horizontal screw centrifuge 4. The insoluble or insoluble organic matter in the wastewater is removed by the solid pre-removal unit, and the COD and SS of the wastewater are reduced. The COD removal rate of the wastewater is ≥30%, and the SS removal rate of the wastewater is ≥50%. The wastewater with part of the solids removed by the two-phase horizontal screw centrifuge 4 enters the flocculation regulating tank 5, and the PAC adding mechanism adds 6-8kg / m 3 After adding PAC, add 0.02-0.55kg / m 3The PAM of the wastewater is in a flocculation and sedimentation state. The wastewater in the flocculation regulating tank 5 is transported to the aeration mechanism 8 by the wastewater conveying mechanism 15. The scum in the wastewater is skimmed off by the skimming mechanism at the top and mixed with the sludge at the bottom, and then discharged to the wastewater storage and conveying mechanism 1 by the debris reflux mechanism 9 for further circulation treatment. The aeration pressure of the aeration mechanism 8 is 0.2-0.5MPa, and the contact time between the wastewater and the compressed air is 45-75 seconds. The organic matter and solids in the wastewater are further removed by the aeration oil removal and solid removal units. The COD removal rate of the wastewater is ≥20%, and the SS removal rate of the wastewater is ≥70%. The heating coil 14 is installed in the slurry collection tank before the heating tank of the oil and water treatment process section of the food waste, and the collected slurry is preheated, which not only reduces the temperature of the wastewater after the heating three-phase separation to remove part of the grease and solids, but also recovers part of the heat to preheat the slurry, reducing the energy consumption of heating the slurry. The sewage pump body transports the wastewater that has been heated and three-phase separated to remove some grease and solids to the heating coil 14, where the wastewater is cooled. The temperature of the wastewater before cooling is generally around 58°C, and is cooled to around 53°C by the heating coil 14. Then the wastewater enters the heat exchanger 11, where the wastewater exchanges heat with the cooling circulating water, and the temperature is reduced to below 38°C. The cooling water circulates in the heat exchanger 11 and the cooling tower 13 through the circulation mechanism 12, taking away the heat of the wastewater and cooling the wastewater.
[0034] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A pretreatment device for food waste sewage, comprising a wastewater storage and conveying mechanism (1), characterized in that: An acid-base regulating tank (3) is arranged on the right side of the wastewater storage and conveying mechanism (1), a lime milk mechanism (2) is arranged outside the acid-base regulating tank (3), a centrifuge feeding mechanism (16) is arranged on the right side of the acid-base regulating tank (3), a two-phase horizontal screw centrifuge (4) is arranged on the right side of the centrifuge feeding mechanism (16), a flocculation regulating tank (5) is arranged on the right side of the two-phase horizontal screw centrifuge (4), a PAM adding mechanism (7) and a PAC adding mechanism (6) are arranged outside the flocculation regulating tank (5), and a wastewater conveying mechanism (15) is arranged on the right side of the flocculation regulating tank (5). An aeration mechanism (8) is arranged on the right side of the wastewater conveying mechanism (15), a debris return mechanism (9) is arranged on the right side of the aeration mechanism (8), the other end of the debris return mechanism (9) is connected to the wastewater storage and conveying mechanism (1), a sewage conveying mechanism (10) is arranged on the outside of the aeration mechanism (8), a heating coil (14) is connected on the right side of the sewage conveying mechanism (10), a heat exchanger (11) is connected on the right side of the heating coil (14), a cooling tower (13) is arranged on the outside of the heat exchanger (11), and a circulation mechanism (12) is arranged on the outside of the cooling tower (13).
2. The pretreatment device for food waste sewage according to claim 1 is characterized in that: The wastewater storage and transportation mechanism (1) comprises a storage tank, a water pipe and a wastewater pump body. The wastewater pump body is arranged in the storage tank. The other end of the wastewater pump body is connected to the water pipe. The other end of the water pipe is arranged in the acid-base adjustment tank (3).
3. The pretreatment device for food waste sewage according to claim 1 is characterized in that: The lime milk mechanism (2) comprises a shell, a lime milk motor, a lime milk stirring roller, a lime milk connecting pipe and a lime milk pump body. The outside of the shell is fixedly connected to the lime milk motor. The output end of the lime milk motor passes through the shell and is fixedly connected to the lime milk stirring roller. The outside of the shell is provided with a lime milk pump body. Both ends of the lime milk pump body are connected to lime milk connecting pipes. One end of the lime milk connecting pipe is connected to the shell, and the other end is connected to the acid-base regulating tank (3).
4. The pretreatment device for food waste sewage according to claim 1, characterized in that: The PAM adding mechanism (7) comprises a box body, a PAM stirring roller, a PAM connecting pipe and a PAM pump body. The box body is provided with a PAM stirring roller. The outside of the box body is fixedly connected to a PAM connecting pipe. The other end of the PAM connecting pipe is connected to the PAM pump body. The output end of the PAM pump body is connected to the PAM connecting pipe. The other end of the PAM connecting pipe is provided in a flocculation regulating tank (5).
5. The pretreatment device for food waste sewage according to claim 1, characterized in that: The PAC adding mechanism (6) comprises a shell, a PAC stirring roller, a PAC connecting pipe and a PAC pump body. The PAC stirring roller is arranged inside the shell. The PAC connecting pipe is fixedly connected to the outside of the shell. The other end of the PAC connecting pipe is connected to the PAC pump body. The output end of the PAC pump body is connected to the PAC connecting pipe. The other end of the PAC connecting pipe is arranged in the flocculation adjustment tank (5).
6. The pretreatment device for food waste sewage according to claim 1, characterized in that: The wastewater conveying mechanism (15) comprises a wastewater connecting pipe and a conveying pump body, the output end of the conveying pump body is connected to the conveying pipe, and the other end of the conveying pipe is arranged in the aeration mechanism (8).
7. The pretreatment device for food waste sewage according to claim 1, characterized in that: The sewage conveying mechanism (10) comprises a sewage pump body and a sewage pipe, the sewage pump output end is fixedly connected to the sewage pipe, and the other end of the sewage pipe is connected to the heating coil (14).
8. The pretreatment device for food waste sewage according to claim 1, characterized in that: The debris reflux mechanism (9) comprises a debris pump body and a debris pipe, the output end of the debris pump body is fixedly connected to the debris pipe, and the other end of the debris pipe is arranged in the wastewater storage and transportation mechanism (1).