Kitchen organic wastewater treatment device

Abstract

The utility model relates to a kitchen organic wastewater treatment device which comprises a reaction tank and a muddy water circulating mechanism, a water inlet is arranged on one side of the bottom of the reaction tank, a scum collecting tank is arranged on the upper portion of the water inlet side, an effluent collecting tank is arranged on the upper portion of the other side, and a scum scraper is arranged on the upper portion of the reaction tank. The muddy water circulating mechanism comprises circulating branch pipes, a circulating main pipe, a circulating pump and a water distribution pipe, at least two muddy water circulating outlets are formed in the lower part of the reaction tank, the circulating branch pipes are connected and communicated with the corresponding muddy water circulating outlets, one end of the circulating main pipe is connected and communicated with each circulating branch pipe, and the other end of the circulating main pipe is connected and communicated with the water distribution pipe; a circulating pump is arranged on the circulating main pipe arranged outside the reaction tank, at least two water injection nozzles are formed in the bottom of the water distribution pipe, and each water injection nozzle comprises a small-diameter compression section and a divergent section at an outlet. The device is reasonable and compact in structure, and can effectively solve the problems of scum leakage and pipeline blockage during hydrolytic acidification, so that muddy water can be fully mixed, and the hydrolytic acidification reaction is stable in operation.

Description

Technical Field

[0001] This utility model relates to a device for treating organic wastewater from kitchen waste, belonging to the technical field of organic wastewater treatment from kitchen waste. Background Technology

[0002] The aqueous phase of pretreated food waste, also known as the three-phase effluent, is currently treated by directly feeding it into an anaerobic digester for a 30-45 day anaerobic reaction. This process involves hydrolysis, acidification, acetic acid production, and methanogenesis to achieve resource utilization of the food waste. However, the long methanogenesis cycle in a stable anaerobic environment results in a large anaerobic digester, increasing investment and operating costs. Certain technologies can be employed to complete the hydrolysis and acidification of the three-phase effluent in a shorter time. This added hydrolysis and acidification process not only shortens the biogas production cycle but also optimizes the anaerobic process.

[0003] Hydrolysis and acidification processes can hydrolyze suspended solids into dissolved organic matter, and transform recalcitrant macromolecules such as carbohydrates, fats and lipids into easily biodegradable small molecules. These small molecules are further transformed into volatile fatty acids under the action of acidifying bacteria.

[0004] Hydrolysis acidification is typically achieved through a hydrolysis acidification reactor, such as the hydrolysis acidification tank disclosed in CN 220766675 U. This reactor is divided into a reaction tank and a sedimentation tank, connected by a top-opening pipe, relying on gravity flow for transport. The sedimentation tank pipe is curved upwards. However, this type of hydrolysis acidification reactor suffers from inadequate mixing of sludge and water, and sludge is prone to sedimentation, thus reducing the hydrolysis acidification efficiency. This is especially problematic in kitchen wastewater, which often contains high levels of organic matter such as plastic particles, chili seeds, and animal and plant residues. Using this type of hydrolysis acidification tank, the high concentration of suspended solids in the wastewater can easily clog the pipes, affecting the hydrolysis acidification effect.

[0005] CN220665048 U discloses a uniform water distribution device for a hydrolysis acidification reaction tank. A filter is installed at the inlet to remove large particles from the incoming water. Uneven water distribution is then addressed through the inlet pipe, multiple spray heads on the collection tray at the bottom of the tank, and a stirrer. However, this hydrolysis acidification reaction tank has a complex structure. Although a filter is installed at the inlet, the three-phase effluent from kitchen wastewater contains small plastic particles, chili seeds, and organic matter such as plant and animal residues. These small particles cannot be completely filtered out and subsequently enter the tank, easily causing pipe blockage. Therefore, it is unsuitable for treating high-solids-content wastewater such as kitchen wastewater. Summary of the Invention

[0006] The purpose of this invention is to provide a kitchen wastewater treatment device with a reasonable and compact structure that can effectively solve the problems of scum leakage and pipeline blockage during hydrolysis and acidification, so that the mud and water can be fully mixed and the hydrolysis and acidification reaction can operate stably.

[0007] The technical solution of this utility model to achieve the above-mentioned objective is: a kitchen wastewater treatment device, characterized in that: it includes a reaction tank and a sludge-water circulation mechanism, wherein the bottom of the reaction tank is provided with an inlet on one side, the reaction tank is provided with a scum collection tank at the upper part of the inlet side and an outlet collection tank at the upper part of the other side, the bottom of the scum collection tank is provided with a scum discharge port and the bottom of the outlet collection tank is provided with an outlet, and a scum scraper is provided at the upper part of the reaction tank, wherein the scum scraper plate on the scum scraper is set in the scum area;

[0008] The sludge-water circulation mechanism includes circulation branch pipes, circulation main pipes, circulation pumps, and water distribution pipes. The lower part of the reaction tank is provided with at least two sludge-water circulation outlets, and the circulation branch pipes are connected to their respective sludge-water circulation outlets. One end of the circulation main pipe is connected to each circulation branch pipe, and the other end is connected to the water distribution pipe. A circulation pump is provided on the circulation main pipe located outside the reaction tank, and a sludge discharge pipe with a valve is provided on the front or rear side of the circulation pump. The water distribution pipe is located below the scraper plate, and at least two spray nozzles are provided at the bottom of the water distribution pipe. The spray nozzles include a small-diameter compression section and a gradually expanding section at the outlet. The diameter d of the compression section is 0.4 to 0.6 times the diameter D of the water distribution pipe, and the cone angle β of the gradually expanding section is between 35 and 60°.

[0009] This utility model discloses a kitchen wastewater treatment device that employs a reaction tank and a sludge-water circulation mechanism. A scraper is installed at the top of the reaction tank, using scraper plates to promptly scrape the scum generated during hydrolysis and acidification into a scum collection tank. This effectively solves the problem of easy leakage of foamy scum during hydrolysis and acidification, making the reaction device operate more stably. The sludge circulation mechanism of this utility model uses circulation branch pipes, a circulation main pipe, a circulation pump, and a distribution pipe. The bottom of the reaction tank has sludge-water circulation outlets at different locations. Therefore, under the action of the circulation pump, sludge-water from different locations at the bottom is introduced into the reaction tank through the circulation branch pipes and circulation main pipe, allowing the wastewater and sludge-water to be mixed multiple times. This significantly reduces sludge deposition at the bottom, ensuring that the sludge is evenly distributed in the reaction tank. This solves the problem of uneven sludge-water distribution during the hydrolysis and acidification reaction. It also solves the problem of plastic particles, chili seeds, and animal and plant residues in kitchen wastewater easily clogging the distribution pipes, thereby improving the overall hydrolysis and acidification efficiency. This invention has a simple structure. It uses an external circulating pump to circulate the material itself hydraulically, which improves the efficiency of hydrolysis and acidification while ensuring stable operation of the hydrolysis and acidification reaction. Attached Figure Description

[0010] The embodiments of this utility model will now be described in further detail with reference to the accompanying drawings.

[0011] Figure 1 This is a schematic diagram of the structure of a kitchen wastewater treatment device according to the present invention.

[0012] Figure 2 This is a schematic diagram of the water distribution pipe of this utility model.

[0013] Wherein: 1—Reaction tank, 1-1—Flushing interface, 1-2—First baffle plate, 1-3—Scum collection tank, 1-4—Scum discharge port, 1-5—Water inlet, 1-6—Sludge-water circulation outlet, 1-7—Second baffle plate, 1-8—Water outlet baffle, 1-9—Water outlet collection tank, 1-10—Water outlet, 1-11—Air outlet, 2—Scum scraper, 2-1—Scum scraper, 3—Water distribution pipe, 3-1—Spray nozzle, 3-11—Gradual closing section, 3-12—Compression section, 3-13—Gradual expansion section, 4—Main circulation pipe, 5—Circulation branch pipe, 6—Sludge discharge pipe, 7—Circulation pump. Detailed Implementation

[0014] See Figure 1 , 2 As shown, this utility model discloses a kitchen wastewater treatment device, comprising a reaction tank 1 and a sludge-water circulation mechanism. (See attached image) Figure 1 As shown, the bottom of the reaction tank 1 of this utility model has an inlet 1-5 on one side. The upper part of the reaction tank 1 on the inlet side has a scum collection trough 1-3, and the upper part of the other side has an outlet collection trough 1-9. The bottom of the scum collection trough 1-3 has a scum discharge port 1-4, and the bottom of the outlet collection trough 1-9 has an outlet 1-10. A scraper 2 is installed at the top of the reaction tank 1. The scraper plate 2-1 on the scraper 2 is located in the scum zone. During the hydrolysis and acidification reaction of kitchen wastewater, the scum formed by organic food residue is scraped into the scum collection trough 1-3 by the scraper plate 2-1 on the scraper 2, and then discharged through the outlet 1-4 for subsequent processing. The scraper 2 of this utility model can be an existing scraper. The motor drives the drive gear of the scraper 2, and the chain is mounted on the drive gear and the driven gear. Therefore, when the chain rotates along the drive gear and the driven gear under power, the scraper plate 2-1 mounted on the chain moves accordingly. Figure 2 As shown, the scraper plate 2-1 scrapes slag from right to left. The bottom end of the scraper plate 2-1 is below the liquid level. As the chain continuously rotates, it scrapes the slag in the slag area at the top of the reaction tank 1 into the slag collection tank 1-3 and discharges it. The wastewater after the hydrolysis and acidification reaction overflows into the effluent collection tank 1-9 and is discharged from the effluent outlet 1-10 to the subsequent treatment process.

[0015] See Figure 1 , 2As shown, the sludge-water circulation mechanism of this utility model includes a circulation branch pipe 5, a circulation main pipe 4, a circulation pump 7, and a water distribution pipe 3. The lower part of the reaction tank 1 is provided with at least two sludge-water circulation outlets 1-6, such as 3 to 6, depending on the volume of the reaction tank 1. The circulation branch pipe 5 is connected to its corresponding sludge-water circulation outlet 1-6. One end of the circulation main pipe 4 is connected to each circulation branch pipe 5, and the other end is connected to the water distribution pipe 3. The circulation pump 7 is provided on the circulation main pipe 4 located outside the reaction tank 1. The circulation main pipe 4 is provided with a sludge discharge pipe 6 with a valve on the front or rear side of the circulation pump 7. Therefore, the sludge-water from different positions in the lower part of the reaction tank 1 is re-entered into the reaction tank 1 through the circulation main pipe 4 and then through the water distribution pipe 3. The wastewater in the reaction tank 1 is used for hydraulic circulation, which greatly reduces the phenomenon of sludge deposition at the bottom. In the reaction tank 1, the sludge-water can be mixed evenly and fully, thereby improving the overall hydrolysis and acidification efficiency.

[0016] See Figure 1 , 2 As shown, the water distribution pipe 3 of this utility model is located below the scraper plate 2-1 and in the upper middle part of the reaction tank 1. The bottom of the water distribution pipe 3 is provided with at least two spray nozzles 3-1. The spray nozzle 3-1 includes a small-diameter compression section 3-12 and a gradually expanding section 3-13 at the outlet. The diameter d of the compression section 3-12 is 0.4 to 0.6 times the diameter D of the water distribution pipe 3. The cone angle of the gradually expanding section 3-13 is between 35 and 60°. The diameter d of the compression section 3-12 of the spray nozzle 3-1 is 0.5 times the diameter D of the water distribution pipe 3. The cone angle of the gradually expanding section 3-13 is 45°. The change in diameter of the spray nozzle 3-1 can form a jet phenomenon, which greatly reduces the phenomenon of water containing high solid content such as chili seeds and animal and plant residues clogging the water distribution pipe 3 in kitchen wastewater, and improves the reliability of the hydrolysis acidification operation of the reaction tank 1.

[0017] See Figure 1 , 2 As shown, the diameter D of the water distribution pipe 3 of this utility model is 100-150mm, such as 110mm, 120mm, etc., and the spray nozzles 3-1 can be provided with 3-6 nozzles. Figure 1 As shown, the water distribution pipe 3 has four spray nozzles 3-1. Each spray nozzle 3-1 also has a tapering section 3-11, which connects to the compression section 3-12. The cone angle of the tapering section 3-11 is between 40° and 50°. Therefore, when wastewater enters the spray nozzles 3-1 from the water distribution pipe 3, it first passes through the tapering section 3-11, then enters the compression section 3-12, and finally passes through the expanding section 3-13 before being sprayed into the wastewater. This three-section tapering spray nozzle design further reduces the likelihood of clogging at the spray nozzles 3-1. (See...) Figure 2As shown, the length l of the compression section 3-12 and the expansion section 3-13 of the nozzle 3-1 of this utility model is 1 / 2 to 2 / 3 of the total length L of the nozzle 3-1. For example, if the length l of the compression section 3-12 and the expansion section 3-13 of the nozzle 3-1 is 3 / 5 of the total length L of the nozzle 3-1, the change in pressure inside the nozzle 3-1 can ensure that the water distribution pipe will not be blocked.

[0018] See Figure 1 As shown, the reaction tank 1 of this invention has a vertically positioned first baffle plate 1-2 on the upper part of the water inlet side, with a height exceeding that of the water distribution pipe 3. The first baffle plate 1-2 and the protruding tank body form a scum collection trough 1-3. The first baffle plate 1-2 allows the scraper plate 2-1 to push the scum over the top of the first baffle plate 1-2 into the scum collection trough 1-3, while wastewater is blocked by the first baffle plate 1-2 and does not enter the scum collection trough 1-3. See Figure 1 As shown, the reaction tank 1 of this utility model has a vertically placed outlet baffle 1-8 on the outlet side, which is higher than the water distribution pipe 3. The outlet baffle 1-8 and the outwardly protruding tank body form an outlet collection trough 1-9. The reaction tank 1 also has a second slag baffle 1-7 on the top of the outlet baffle 1-8. The second slag baffle 1-7 is inverted L-shaped. The outer end of the second slag baffle 1-7 is connected to the tank wall of the outlet collection trough 1-9, and the other side is vertically placed on the inner side of the outlet baffle 1-8 and exceeds the center line of the water distribution pipe 3. Therefore, the second slag baffle 1-7 and the outlet baffle 1-8 form an outlet channel, which reduces the accumulation of scum on the outlet side and reduces the interruption of wastewater in the reaction tank 1, thereby improving the hydrolysis acidification efficiency.

[0019] See Figure 1 As shown, the reaction tank 1 of this utility model is provided with a flushing interface 1-1 at the upper part of the scum collection tank 1-3, which can be used to flush the scum collection tank 1-3 as needed. The bottom of the reaction tank 1 on the water outlet side is provided with an air outlet 1-11 to discharge the mud and water at the bottom as needed.

[0020] like Figure 1 , 2As shown, the device of this invention is used to treat and utilize three-phase wastewater from a kitchen wastewater project. The kitchen wastewater enters the reaction tank 1 through inlets 1-5 at the bottom, where it mixes with the sludge in the reaction tank 1 to undergo a hydrolysis and acidification reaction. The circulation pump 7 and circulation time are automatically or manually controlled by a PLC control cabinet. The sludge in the lower part of the reaction tank 1 enters the main circulation pipe 4 through the sludge circulation outlets 1-6 and the corresponding circulation branch pipes 5, and finally flows into the distribution pipe 3. During this process, sludge from different locations is... The water is remixed and then sprayed downwards from the nozzles 3-1 of the upper water distribution pipe 3. The cross-jet flow from each nozzle 3-1 stirs the wastewater, achieving a uniform distribution of mud and water. The foam and scum produced during hydrolysis and acidification are scraped into the scum collection tank 1-3 by the scraper plate 2-1 on the scraper 2, and then discharged through the scum discharge port 1-4. The foam and scum can be cleaned continuously or intermittently as needed. The wastewater after hydrolysis and acidification overflows into the effluent collection tank 1-9 and is then discharged from the effluent port 1-10. Excess sludge in the reaction tank 1 can be discharged through the sludge discharge pipe 6 or from the bottom drain port 1-11 as needed. The kitchen wastewater treatment device of this utility model treats three-phase kitchen wastewater. The parameters of the influent and after hydrolysis and acidification are shown in Table 1.

[0021] Table 1

[0022] parameter SS (mg / L) <![CDATA[NH3-N(mg / L)]]> TN (mg / L) COD (mg / L) VFA (mg / L) amination rate Acidification rate Water ingress 43171 295 2156 84062 17375 13.68% 20.67% Out of water 37205 1694 2562 79788 25470 66.12% 31.92%

[0023] As can be seen from Table 1, the biodegradability of the three-phase wastewater from the kitchen is greatly improved after hydrolysis and acidification, which effectively reduces the operating cost of subsequent treatment and utilization equipment.

Claims

1. A device for treating organic wastewater from kitchen waste, characterized in that: The reaction tank (1) includes a reaction tank (1) and a mud-water circulation mechanism. The reaction tank (1) has an inlet (1-5) on one side of its bottom. The reaction tank (1) has a scum collection trough (1-3) on the upper part of the inlet side and an outlet collection trough (1-9) on the upper part of the other side. The scum collection trough (1-3) has a scum discharge port (1-4) at the bottom and the outlet collection trough (1-9) has an outlet (1-10) at the bottom. The reaction tank (1) has a scum scraper (2) on the upper part. The scum scraper (2-1) on the scum scraper (2) is set in the scum area. The sludge-water circulation mechanism includes circulation branch pipes (5), circulation main pipes (4), circulation pumps (7), and water distribution pipes (3). The reaction tank (1) has at least two sludge-water circulation outlets (1-6) at its lower part, and the circulation branch pipes (5) are connected to their respective corresponding sludge-water circulation outlets (1-6). One end of the circulation main pipe (4) is connected to each circulation branch pipe (5), and the other end is connected to the water distribution pipe (3). A circulation pump (7) is installed on the circulation main pipe (4) located outside the reaction tank (1), and the circulation main pipe (7)... 4) A sludge discharge pipe (6) with a valve is provided on the front or rear side of the circulating pump (7); the water distribution pipe (3) is located at the lower part of the scraper plate (2-1), and the bottom of the water distribution pipe (3) is provided with at least two spray nozzles (3-1). The spray nozzle (3-1) includes a small-diameter compression section (3-12) and a gradually expanding section (3-13) at the outlet. The diameter d of the compression section (3-12) is 0.4 to 0.6 times the diameter D of the water distribution pipe (3), and the cone angle β of the gradually expanding section (3-13) is between 35 and 60°.

2. The kitchen wastewater treatment device according to claim 1, characterized in that: The diameter D of the water distribution pipe (3) is 100-150mm, and there are 3-6 spray nozzles (3-1).

3. A kitchen wastewater treatment device according to claim 1 or 2, characterized in that: The water nozzle (3-1) on the water distribution pipe (3) is also provided with a tapering section (3-11), which is connected to the compression section (3-12), and the cone angle α of the tapering section (3-11) is between 40 and 50°.

4. A kitchen wastewater treatment device according to claim 1 or 2, characterized in that: The length l of the compression section (3-12) and the expansion section (3-13) on the nozzle (3-1) of the water distribution pipe (3) is 1 / 2 to 2 / 3 of the total length L of the nozzle (3-1).

5. The kitchen wastewater treatment device according to claim 1, characterized in that: The reaction tank (1) is provided with a first baffle plate (1-2) on the upper part of the water inlet side, which is vertical and has a height exceeding that of the water distribution pipe (3). The first baffle plate (1-2) and the convex tank body form a scum collection trough (1-3). The reaction tank (1) is provided with a water outlet baffle (1-8) on the water outlet side, which is vertical and has a height exceeding that of the water distribution pipe (3). The water outlet baffle (1-8) and the convex tank body form a water outlet collection trough (1-9). The reaction tank (1) is also provided with a second baffle plate (1-7) on the top of the water outlet baffle (1-8). The second baffle plate (1-7) is inverted L-shaped. The outer end of the second baffle plate (1-7) is connected to the tank wall of the water outlet collection trough (1-9), and the other side is vertically placed on the inner side of the water outlet baffle (1-8) and exceeds the center line of the water distribution pipe (3).

6. A kitchen wastewater treatment device according to claim 1 or 5, characterized in that: The reaction tank (1) is provided with a flushing port (1-1) at the top of the scum collection tank (1-3), and a drain port (1-11) is provided at the bottom of the reaction tank (1) on the effluent side.

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