CN102632069B - Device for commonly treating kitchen waste and domestic sewage - Google Patents

Abstract

The invention discloses a device for co-processing kitchen waste and domestic sewage, which has a first storage box storing kitchen waste and a second storage box storing domestic sewage at equal heights, and the bottom of the storage box is connected to the top of the quantitative box directly below , the bottoms of the two quantitative boxes are connected to the pulverizer directly below at the same time, and the preheater, the closed fermentation room and the closed gas production room are connected directly below the pulverizer in turn. The ratio of kitchen waste to domestic sewage is 1:3. The sample period is 5-7 days; the preheating temperature of the preheater is 25°C-40°C; the internal temperature of the fermentation room is 25°C-40°C, and the pH is 6.1-7.4; 25°C-40°C; it can carry out joint anaerobic fermentation of kitchen waste and domestic sewage, and can control the mixing ratio, temperature, pH and other fermentation conditions. Different fermentation stages are fermented in two closed rooms, and the speed and efficiency are improved. .

Description

A co-processing device for kitchen waste and domestic sewage

technical field

The invention relates to a device for co-processing kitchen waste and domestic sewage, belonging to the technical field of waste treatment.

Background technique

Kitchen waste has the characteristics of high water content, high organic matter content, and rich nutrients; domestic sewage has a high concentration of organic matter, contains organic matter, nitrogen and phosphorus nutrients, suspended solids, and germs and other pollutants, and is rich in microorganisms. The environmental pollution caused by waste garbage and domestic sewage has constituted a potential threat to the life and health of residents.

Traditional kitchen waste disposal mainly includes composting, feed production, biological hydrogen production and methane fermentation, etc.; domestic sewage disposal includes high-efficiency algae pond treatment, constructed wetland sewage treatment, and underground infiltration system treatment. The treatment efficiency of residual garbage and domestic sewage is low. Foreign scholars Myungyeol Lee et al. { Journal of Bioscience and Bioengineering , v 108, n 5, p 408-413, November 2009} divided the co-processing reaction of kitchen waste and domestic sewage into two stages of acid production and gas production. Different conditions have different effects on gas production efficiency. Domestic scholar Zhao Songmin and others proposed different types of kitchen waste and activated sewage in the anaerobic fermentation of kitchen waste based on activated sludge to produce acid {Journal of Environmental Engineering, 2011, 01, 5(1):205-208}. Effect of mud inoculation ratio on fatty acid yield, solution pH and COD removal rate. Zhang Houhu et al. proposed the effect of domestic sewage inflow and water inflow frequency on biogas production in the Taihu Lake Basin rural scattered residents' domestic garbage and domestic sewage co-disposal and enhanced biogas production technology {Journal of Ecology and Rural Environment, 2010, 26(1):19-23} The influence of air efficiency. However, none of the above documents fully disclosed the impact of the addition ratio of kitchen waste and domestic sewage on the treatment efficiency and gas production efficiency, nor did they disclose a set of stable and efficient kitchen waste and domestic sewage co-processing devices.

Existing kitchen waste and domestic sewage treatment devices often have only one storage box for storing kitchen waste and domestic sewage. The pulverizer and preheater are connected to the bottom of the storage box. There are stirring and temperature-regulating equipment in the gas room. This type of device fails to store kitchen waste and domestic sewage separately, so the addition ratio between the two cannot be controlled. The reaction device has only one fermentation and gas production room, and the hydrolysis and acid production stages in the fermentation process cannot be separated from the gas production stage, so the rate of gas production is low.

Contents of the invention

The object of the present invention is to address the deficiencies of the prior art, and provide a kitchen waste and domestic sewage co-disposal device with low treatment cost, good treatment effect, high gas production efficiency and no secondary pollution.

The technical solution adopted by the present invention is: adopting the first and second storage boxes of equal height, kitchen waste is stored in the first storage box, domestic sewage is stored in the second storage box, and the bottom of the first storage box is connected to the The top of the first quantitative tank and the bottom of the second storage tank are connected to the top of the second quantitative tank directly below. The bottom of the first and second quantitative tanks are connected to the pulverizer directly below through pipelines at the same time, and the pulverizer is directly connected to the preheater in turn. , a closed fermentation room and a closed gas production room, the top of the fermentation room is equipped with a stirrer, the bottom of the fermentation room is a structure that slopes upward from left to right, and a cylindrical net is set between the fermentation room and the left part of the gas production room screen.

Further, the amount ratio of kitchen waste in the first storage tank to domestic sewage in the second storage tank of the present invention is 1:3, and the sampling cycle of kitchen waste and domestic sewage is 5-7 days; the preheater The preheating temperature is 25°C-40°C; the internal temperature of the fermentation room is 25°C-40°C, and the pH is 6.1-7.4; the internal pH of the gas production room is 6.1-7.4, and the temperature is 25°C-40°C.

After the present invention adopts the above-mentioned technical scheme, it has the following beneficial effects :

1. The present invention can carry out combined anaerobic fermentation of kitchen waste and domestic sewage, kitchen waste provides nutrients, domestic sewage provides nitrogen and a large number of microorganisms, and establishes a benign and complementary relationship between two different digested materials, A set of devices can treat kitchen waste and domestic sewage at the same time, with high efficiency and low investment cost; it realizes the treatment and resource utilization of kitchen waste and domestic sewage, and has high economic and environmental protection value.

2. The present invention can pulverize fermentation materials, and can control the mixing ratio, temperature, pH and other fermentation conditions of kitchen waste and domestic sewage, especially the fixed ratio mixing of kitchen waste and domestic sewage, which is conducive to improving the speed and efficiency of fermentation. The treatment effect of kitchen waste and domestic sewage is very good, and there is no secondary residual substance pollution, which can curb environmental pollution and relieve the pressure of domestic waste treatment.

3. The present invention divides different fermentation stages into two airtight rooms, which improves the efficiency and speed of fermentation. The biochemical reactions in the hydrolysis acid production stage and the methane production stage are not affected. Therefore, the fermentation efficiency is very high, and the production efficiency is high. Gas works well.

4. The fermentation process in the present invention is carried out in a closed container, which belongs to anaerobic fermentation, does not need artificial oxygen supply to promote the reaction speed, and produces no malodorous gas.

Description of drawings

Fig. 1 is a structural representation of the present invention;

In the figure: 1. kitchen waste entrance; 2-1. first pressure regulating pipe; 2-2. second pressure regulating pipe; 2-3. third pressure regulating pipe; 2-4. fourth pressure regulating pipe; 3. Urinal sewage inlet; 4. Washing water inlet; 5. Second storage tank; 6. First switch valve; 7. Second switch valve; 8. Pulverizer; 9. Preheater; 10. Agitator; 11. Gas outlet; 12. Gas production room; 13. Water outlet; 14. The third on-off valve; 15. Outlet; 16. Cylindrical mesh screen; 17. Fermentation room; 18. The fourth on-off valve; 19. The fifth switching valve; 20. the first storage tank; 21-1. the first quantitative tank; 21-2. the second quantitative tank. the

Detailed ways

The structure of each part of the present invention and connection relationship as shown in Figure 1, the left and right positions of the top of the present invention are respectively provided with a storage box, the left position is the first storage box 20, the right position is the second storage box 5, the first storage box 20 and the second storage box 5 equal heights are installed. The top opening of the first storage box 20 is the kitchen waste inlet 1, and the first quantitative box 21-1 is installed directly below the first storage box 20, and the bottom of the first storage box 20 communicates with the first quantitative box 21-1. 1 top, the fifth on-off valve 19 is installed between the bottom of the first storage tank 20 and the top of the first quantitative tank 21-1, between one side of the first storage tank 20 and one side of the first quantitative tank 21-1 The first pressure regulating pipe 2-1 is connected, the other side of the first storage tank 20 is connected with the second pressure regulating pipe 2-2, and the second pressure regulating pipe 2-2 communicates with the atmosphere. A fourth on-off valve 18 is installed at the bottom of the first quantitative tank 21-1.

There are two openings on the top of the second storage box 5, which are respectively the urinal sewage inlet 3 and the washing water inlet 4, and the second quantitative box 21-2 is installed directly below the second storage box 5, and the second storage box 5 The bottom is communicated with the top of the second quantitative tank 21-2, and the first switch valve 6 is installed between the second storage tank 5 bottom and the second quantitative tank 21-2 top, at the second storage tank 5 side and the second quantitative tank The third pressure regulating pipe 2-3 is connected between one side of 21-2, and the fourth pressure regulating pipe 2-4 is connected to the other side of the second storage tank 5, and the fourth pressure regulating pipe 2-4 communicates with the atmosphere. The second on-off valve 7 is installed at the bottom of the second quantitative box 21-2.

The bottoms of the first quantitative box 21-1 and the second quantitative box 21-2 are simultaneously connected to the pulverizer 8 directly below the pulverizer 8 through pipelines, and the pulverizer 8 is connected to the preheater 9 directly below the preheater 9, which is an airtight fermentation 17, the preheater 9 is directly connected to the fermentation room 17, three agitators 10 are installed on the top of the fermentation room 17, a discharge port 15 is set at the bottom left of the fermentation room 17, and the bottom of the fermentation room 17 is connected to the airtight gas production room 12 , and the bottom of the fermentation room 17 is an inclined structure, which slopes upward from left to right. A cylindrical screen 16 is set between the fermentation room 17 and the left part of the gas production room 12, and the third switching valve 14 is located below the cylindrical screen 16. The gas outlet 11 is connected to the upper right of the gas production room 12, and the gas production room The lower right side of 12 is the water outlet 13 that communicates with the outside.

When the present invention works, kitchen waste and domestic sewage are mixed under anaerobic conditions to produce biogas, and rely on the synergistic effect of various anaerobic microorganisms such as facultative anaerobic bacteria and obligate anaerobic bacteria to realize kitchen waste and domestic sewage. For the co-disposal of sewage, kitchen waste provides nutrients, and domestic sewage provides nitrogen and a large number of microorganisms. A benign and complementary relationship is established between the two materials, which are finally fermented into methane and carbon dioxide to form biogas. Specifically: kitchen waste is stored in the first storage box 20 through the kitchen waste inlet 1, and domestic sewage such as urinal dirt and washing water is stored in the second storage box through the urinal sewage inlet 3 and washing water inlet 4 respectively. In box 5, the first quantitative box 21-1 and the second quantitative box 21-2 respectively control the volume ratio of kitchen waste and domestic sewage, realizing the fixed ratio control of kitchen waste and domestic sewage, and controlling the ratio of kitchen waste and domestic sewage. The ratio of domestic sewage is 1:3, and the sampling period is 5-7 days, which can effectively realize the treatment and resource utilization of kitchen waste and domestic sewage. Afterwards, they enter into the pulverizer 8 to be crushed into granules, so that various substances can be fully contacted, and then preheated to 25°C-40°C through the preheater 9, and are discharged into the fermentation room 17 for fermentation for several hours, and the fermentation room 17 maintains the temperature The temperature is 25°C-40°C, the pH is 6.1-7.4, and the stirrer 10 is often started during the fermentation process to make it fully mixed and contacted to carry out the hydrolysis reaction and acid production reaction to speed up the reaction speed. After a certain period of time, open the third on-off valve 14, and filter the digestive juice through the columnar screen 16 into the gas production room 12. Anaerobic fermentation produces gases such as methane. The fermentation process is divided into three stages: hydrolysis, acidification, and methanation, which are respectively carried out in the fermentation room 17 and the gas production room 12. The hydrolysis and acidification stages are carried out in the fermentation room 17, and the methanation stage is carried out in the gas production room 12. The efficiency of the reaction process is greatly improved. The fermentation process is divided into three stages: hydrolysis, acidification, and methanation. The first stage is the hydrolysis stage. Anaerobic bacteria can be divided into cellulolytic bacteria, lipolytic bacteria and proteolytic bacteria according to the decomposed objects. They hydrolyze polysaccharides respectively into simple sugars, proteins into peptides and amino acids, and fats into glycerol and fatty acids. The second stage is the acidification stage, in which higher fatty acids are decomposed into acetic acid and hydrogen by acetogenic bacteria such as colloidal acetic acid bacteria and certain Clostridium sp. Aromatic acids, such as phenylacetic acid and indoleic acid, produced when digesting protein, are also broken down by second-stage bacteria to produce acetic acid and hydrogen. The third stage is the methanation stage, where the methanogens convert the acetic acid into methane and CO ₂ . Since the acidic substances formed in the acid production stage may inhibit the activity of methanogens, the second and third stages are separated into different digestion tanks, and the conditions such as temperature and pH of the fermentation room 17 and the gas production room 12 are controlled It can accelerate fermentation, improve gas production efficiency and treatment effect. The output of the fermentation room 17 is biogas residue, which is taken out from the discharge port 15 and can be used for composting. The water outlet 13 of the gas production room 12 removes liquid substances rich in nitrogen and phosphorus substances, which have high fertilizer properties and can be used as liquid fertilizers. Returning to the field, the gas outlet 11 discharges methane, which has a high calorific value and can be used as fuel gas.

Claims (3)

1. A device for co-processing kitchen waste and domestic sewage, characterized in that it has first and second storage boxes (20, 5) of equal height, kitchen waste is stored in the first storage box (20), and the second Domestic sewage is stored in the second storage box (5). The bottom of the first storage box (20) is connected to the top of the first quantification box (21-1) directly below, and the bottom of the second storage box (5) is connected to the second quantitative box (21-1) directly below. The top of the quantitative box (21-2), the bottom of the first and second quantitative boxes (21-1, 21-2) are connected to the pulverizer (8) directly below through the pipeline at the same time, and the pulverizer (8) is directly connected to the pre- The heater (9), the closed fermentation room (17) and the closed gas production room (12), the preheater (9) is directly connected to the fermentation room (17), and the top of the fermentation room (17) is provided with a stirrer ( 10), the bottom of the fermentation room (17) is connected to the airtight gas production room (12). Cylindrical mesh screens (16) are provided between the locations. 2. A device for co-processing kitchen waste and domestic sewage according to claim 1, characterized in that: the kitchen waste in the first storage tank (20) and the domestic sewage in the second storage tank (5) The volume ratio is 1:3, the sampling cycle of kitchen waste and domestic sewage is 5-7 days; the preheating temperature of the preheater (9) is 25°C-40°C; the internal temperature of the fermentation room (17) is 25°C- 40°C, pH 6.1-7.4; internal pH of the gas production room (12) is 6.1-7.4, temperature 25°C-40°C. 3. A kitchen waste and domestic sewage co-disposal device according to claim 1, characterized in that: a discharge port (15) is provided at the bottom left of the fermentation room (17), and a cylindrical mesh screen (16) is provided below There is a third switch valve (14), the upper right side of the gas production room (12) is connected to the gas outlet (11), and the lower right side of the gas production room (12) is the water outlet (13) connected to the outside; the first storage box (20) A fifth switch valve (19) is provided between the bottom and the top of the first quantitative tank (21-1), a fourth switch valve (18) is provided at the bottom of the first quantitative tank (21-1), and the first storage tank (20) Connect the first pressure regulating tube (2-1) between one side and the first quantitative tank (21-1), and the other side of the first storage tank (20) is connected to the second regulator connected to the atmosphere. pressure pipe (2-2); a first switch valve (6) is provided between the bottom of the second storage tank (5) and the top of the second quantitative tank (21-2), and the bottom of the second quantitative tank (21-2) is There is a second switching valve (7), a third pressure regulating pipe (2-3) is connected between one side of the second storage tank (5) and one side of the second quantitative tank (21-2), and the second storage tank (5 ) The other side is connected to the fourth pressure regulating tube (2-4) which communicates with the atmosphere.

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