Intermittent pig raising wastewater nitrogen and phosphorus synchronous recovery device

Abstract

An intermittent pig raising wastewater nitrogen and phosphorus synchronous recovery device comprises a grating tank, a regulating tank, an anaerobic tank, an aeration tank, a tail gas treatment device, a sedimentation tank, a discharge well, a sediment collection device and ancillary facilities, and the ancillary facilities mainly comprise a dosing device, a diaphragm fan, a pH monitoring probe, a liquid level sensor, a control panel and a signal receiver. The device disclosed by the utility model is simple in process, low in cost and short in construction period, the nitrogen and phosphorus recovery rates of the aeration tank to inlet water exceed 85%, and equipment can be started for use and shut down at any time. The device disclosed by the utility model not only meets the high-efficiency treatment of the pig raising wastewater, but also realizes the resource utilization of wastes, and has higher economic value and application prospect.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the breeding industry waste treatment and recovery equipment technical field, concretely relates to an intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. BACKGROUND

[0002] The pig wastewater contains high concentration ammonia nitrogen and phosphorus, and if directly discharging, will cause water body eutrophication, pollute surface water and soil, and pose great threat to ecological environment. In addition, the high concentration nitrogen and phosphorus in the pig wastewater is also a kind of resource with high recovery value. How to scientifically and reasonably treat and utilize the pig wastewater is the main research direction of the pig wastewater treatment at present.

[0003] At present, the treatment methods of high concentration nitrogen and phosphorus in the pig wastewater mainly include activated sludge method, breakpoint chlorination method, ion exchange method, stripping method and struvite crystallization method. The above processes can reduce the nitrogen and phosphorus content of the pig wastewater to a certain extent, but the resource recovery rate is relatively low, or it is difficult to simultaneously achieve effective nitrogen removal and efficient phosphorus removal in the treatment process.

[0004] The struvite crystallization method is a new type of nitrogen and phosphorus recovery technology developed in recent decades, and the reaction utilizes magnesium salt and nitrogen and phosphorus in the wastewater to co-precipitate magnesium ammonium phosphate crystals with a molar ratio of Mg:N:P=1:1:1, which is a high-quality slow-release fertilizer for agriculture. However, the content of ammonia nitrogen in the pig wastewater is much higher than that of phosphate, and it is still difficult to effectively remove the residual ammonia nitrogen in the pig wastewater after single process treatment. The stripping method is a simple and efficient nitrogen removal technology, and if the struvite crystallization method and the stripping method are combined in the pig wastewater recovery process, the effective recovery and utilization of high concentration nitrogen and phosphorus in the pig wastewater can be realized simultaneously. The current treatment device cannot meet the operation requirements of the above processes, so it is of great research significance and application value to develop a device that can simultaneously recover nitrogen and phosphorus from pig wastewater. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing an intermittent pig wastewater nitrogen and phosphorus synchronous recovery device, which can ensure effective recovery of nitrogen and phosphorus in pig wastewater, prevent harmful gas from being discharged, and make the recovery of sedimentary products more convenient.

[0006] The utility model is implemented through the following technical solutions.

[0007] The intermittent pig wastewater nitrogen and phosphorus synchronous recovery device comprises a grating pool, an adjusting pool, an anaerobic pool, an aeration tank, a tail gas treatment device, a sedimentation tank, a discharge well, a sediment collection device and auxiliary facilities.

[0008] The aforementioned bar screen and equalization tank are located below ground level and are directly connected by a first drainage pipe. A sewage lift pump is installed between the equalization tank and the anaerobic tank located above ground level. The anaerobic tank is tightly connected to the aeration tank, with an inlet on the side near the aeration tank. The aeration tank is located on a platform slightly higher than ground level and has an exhaust gas treatment device installed on its top. The sedimentation tank is located above ground level near the aeration tank and is connected to the aeration tank via a check valve. The bottom of the sedimentation tank has a T-shaped discharge port, with a right-angle sludge discharge valve and a drain valve installed at each end of the T-shaped discharge port. A sludge treatment device is installed below the right-angle sludge discharge valve, and the drain valve is connected to the discharge well by a second drainage pipe.

[0009] The aeration tank is equipped with an aeration assembly at its lower end. The aeration assembly includes an aeration head, a diaphragm blower, and an aeration pipe. The diaphragm blower is installed outside the aeration tank, and the aeration connection pipe (GAS) of the aeration pipe is connected to the output end of the diaphragm blower. All aeration heads are installed on the aeration pipe.

[0010] The aeration tank is also equipped with a pH monitoring probe to monitor changes in the water's acidity or alkalinity, thereby ensuring the aeration tank maintains an optimal reaction environment. A level sensor is also installed in the aeration tank to monitor the level of the wastewater. Both the level sensor and the pH monitoring probe are connected to a signal receiver. An observation port is located at the top of the aeration tank.

[0011] The dosing device consists of a dosing tank, a metering pump, and a delivery pipe (YJ). The dosing tank is connected to the aeration tank via the delivery pipe. The chemicals in the dosing tank are a mixed alkaline turbid solution of tricalcium magnesium aluminate powder, calcined dolomite powder, and sodium hydroxide, mixed in a certain proportion according to the influent nitrogen and phosphorus concentration and the required pH value for the reaction. The control panel is connected to an information receiver for controlling the operation of various electrically powered facilities in the system.

[0012] The system includes a grit chamber and a regulating chamber, used to collect pig wastewater after dry-wet separation from the pigsty. The grit chamber blocks more solid impurities, while the regulating chamber collects the wastewater and adjusts its quality and quantity. An anaerobic tank, aeration tank, and exhaust gas treatment device are used to purify the incoming wastewater and collect the waste gas generated during the reaction. A sedimentation tank, discharge well, and sedimentation collection device are used for solid-liquid separation of the wastewater after the reaction. Among the auxiliary facilities, a dosing device introduces an alkaline mixture of tricalcium magnesium aluminate and calcined dolomite into the aeration tank, allowing it to react with the pig wastewater and increasing the alkalinity of the water. A diaphragm blower provides air to the aeration tank, acts as a stirrer, and removes ammonia from the water. A pH monitoring probe and level sensor monitor the pH value and level changes during the aeration tank treatment process. The control panel contains the overall control program for the electrical components of the system.

[0013] The intermittent nitrogen and phosphorus synchronous recovery device for pig farm wastewater described in this utility model mainly includes the following steps for nitrogen and phosphorus recovery from pig farm wastewater.

[0014] S1, the pig wastewater after solid-liquid separation is subjected to preliminary filtration through a grid pool and homogenization treatment through a conditioning pool.

[0015] S2, the sewage is lifted to an anaerobic tank by a sewage lifting pump for anaerobic treatment, and then flows into an aeration tank to react with mixed alkali liquid added through a dosing device under aeration condition, a diaphragm air blower is started, the aeration tank starts to intake air, the reaction time is 5 hours, the pH value change in the reaction process is monitored to maintain between 9-10, the gas generated in the process is absorbed by a tail gas treatment device, after 5 hours, when the aeration tank is emptied, the sewage lifting pump is opened to carry out the next round of reaction.

[0016] S3, the reacted sewage flows to a sedimentation tank by itself, after 2 hours of sedimentation, the sedimentation product is discharged into a sedimentation collection device, the effluent flows to a discharge well, after the sedimentation tank is emptied, the bottom valve is closed, and the wastewater after the reaction of the next round of aeration tank enters.

[0017] The device has the beneficial results.

[0018] (1) The device has simple pig wastewater treatment method process, the nitrogen and phosphorus recovery rates of the aeration tank to the water are all more than 85%, the investment operation is fast, the maintenance cost is low, the construction period is short, and the device can be automatically operated.

[0019] (2) According to the water quality and quantity of the pig wastewater, the pig wastewater can be treated controllably by adjusting and controlling the water inflow, operation time and dosing amount, and the equipment can be started and stopped at any time.

[0020] (3) The device can efficiently recover the nitrogen and phosphorus nutrients in the pig wastewater, realizes the resource utilization of the waste, and has high economic value and application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device.

[0022] The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. The device is a whole structure schematic view of the intermittent pig wastewater nitrogen and phosphorus synchronous recovery device. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are some embodiments but not all of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application. Unless otherwise defined, the technical terms or scientific terms used herein should be understood as the common meanings by those skilled in the art. The similar words such as "comprise" used herein mean that the elements or objects before the words cover the elements or objects listed after the words and their equivalents, and do not exclude other elements or objects.

[0024] Referring to Figure 1 The present application provides an intermittent pig wastewater nitrogen and phosphorus synchronous recovery device, which comprises a grid pool 5, an adjusting pool 4, an anaerobic pool 3, an aeration pool 1, a sedimentation pool 2, a sludge treatment device 12, a diaphragm fan 72, a dosing device 6, a tail gas treatment device 11 and a discharge well 13.

[0025] The grid pool 5 and the adjusting pool 4 are arranged below the ground, and the grid pool 5 and the adjusting pool 4 are directly connected by a first drain pipe 51. The adjusting pool 4 is provided with a sewage lifting pump 41 between the adjusting pool 4 and the anaerobic pool 3 arranged above the ground. The anaerobic pool 3 is closely connected with the aeration pool 1, and a water inlet 31 is formed on the side close to the aeration pool 1. The aeration pool 1 is arranged on a water platform 14 slightly higher than the ground, and the top is provided with the tail gas treatment device 11. The sedimentation pool 2 is arranged above the ground and close to the aeration pool 1, and is connected with the aeration pool 1 through a check valve 81. The bottom of the sedimentation pool 2 is provided with a T-shaped discharge port 21. The two ends of the T-shaped discharge port 21 are respectively provided with a right-angle sludge discharge valve 82 and a drain valve 83. The sludge treatment device 12 is arranged below the right-angle sludge discharge valve 82. The drain valve 83 is connected with the discharge well 13 through a second drain pipe 52.

[0026] The aeration pool 1 is provided with an aeration assembly at the lower end. The aeration assembly comprises an aeration head 71, a diaphragm fan 72 and an aeration pipe 73. The diaphragm fan 72 is arranged outside the aeration pool 1. The aeration pipe 73 is connected to the output end of the diaphragm fan 72. The aeration head 71 is arranged on the aeration pipe 73.

[0027] The aeration tank 1 is also provided with a pH monitoring probe 91 for monitoring the change of the water body's pH value to ensure the optimal reaction pH environment in the aeration tank. The aeration tank 1 is also provided with a liquid level sensor 92 for monitoring the height of the sewage liquid level in the aeration tank 1. The liquid level sensor 92 and the pH monitoring probe 91 are connected with the signal receiver 15, and the upper end of the aeration tank 1 is provided with an observation port 16.

[0028] The device also comprises a dosing device 6 which is composed of a dosing barrel 61, a metering pump 62 and a medicine delivery pipe 63. The dosing barrel 61 is connected to the aeration tank 1 through the medicine delivery pipe 61. The medicine in the dosing barrel 61 is a mixed alkaline turbid liquid of magnesium-aluminum acid tricalcium powder, calcined dolomite powder and sodium hydroxide according to the water inlet nitrogen and phosphorus concentration and the required pH value of the reaction in a certain proportion. The control panel 10 is connected with the information receiver 15 for controlling the operation of each power supply facility in the system.

[0029] When the device is working, the sewage after fecal separation treatment first enters the grid tank 5, and the fine grid performs preliminary filtration on the sewage. The feces and large particle impurities in the sewage are intercepted at the fine grid, and the filtered sewage flows into the adjusting tank 4 through the first drain pipe 51 for storage, so as to homogenize the water quality. Then the sewage is pumped into the anaerobic tank 3 by the lifting pump 41 for anaerobic treatment, and most of the organic nitrogen and phosphorus in the sewage is converted into ammonium nitrogen and phosphate for subsequent reaction.

[0030] As the sewage is pumped into the anaerobic tank 3, the sewage liquid level rises to the water inlet 31, and the sewage overflows into the aeration tank 1. The aeration tank 1 is provided with a liquid level sensor 92. When the liquid level sensor 92 detects that the liquid level of the aeration tank 1 reaches the same height as the water inlet 31, the signal receiver 14 transmits a signal to the control panel 10, the control panel 10 controls to close the sewage lifting pump 41 and starts the metering pump 62, and the alkaline liquid in the dosing barrel 61 is injected into the aeration tank through the medicine delivery pipe 63. After a period of time, the metering pump 62 is closed, and the diaphragm blower 72 is started for oxygenation and aeration. At this time, the free nitrogen and phosphorus in the sewage reacts with the alkaline liquid in the aeration tank to generate struvite crystal precipitate, and under alkaline conditions, the remaining ammonia nitrogen in the wastewater is collected in the form of ammonia gas by the tail gas treatment device 11 at the top of the aeration tank 1.

[0031] The reaction time of the aeration tank 1 is 5 hours. After 5 hours, the check valve 21 is automatically opened, and the solid-liquid mixed sewage is naturally introduced into the sedimentation tank 2. When the liquid level sensor 92 detects that the sewage liquid level drops to the height of the check valve 81, a signal is transmitted to the control panel 10, the check valve 81 is closed, and the sewage lifting pump 41 is started for the next round of water inlet. After that, the sewage in the sedimentation tank 2 is allowed to stand for solid-liquid separation. The standing time is 2 hours. At this time, the upper part of the sedimentation tank 2 is clear water, the right-angle sludge valve 82 at one end of the T-shaped discharge port 21 is started to discharge the sediment at the lower part into the sediment collection device 12. When the clear water reaches the inlet of the T-shaped discharge port 21, the right-angle sludge valve 82 is closed, and the water discharge valve 83 at the other end is opened. The clear water is discharged into the discharge well 13 through the second water discharge pipe 52. Specifically, the sediment is a mixture of suspended solids in the sewage, and struvite crystals (MgNH4PO4·6H2O) and calcium-phosphorus (Ca-P) precipitates.

[0032] In some embodiments, the introduction area in the sedimentation tank 2 for introducing the sewage can concentrate the discharge of the sewage, and is provided with a check valve 81. In fact, the check valve 81 can avoid the backflow of the sewage introduced into the sedimentation tank 2.

[0033] In some embodiments, in the dosing device 6, magnesium-aluminum tricalcium, calcined dolomite and sodium hydroxide are added into the dosing barrel in a mass ratio of 1:5:1, mixed and matched into lye, and the addition amount is controlled according to the nitrogen and phosphorus concentrations of the water inlet.

[0034] In some embodiments, the bottom of the aeration tank 1 is provided with an aeration device to promote the flow of the wastewater and the lye, accelerate the reaction, and make the wastewater reach a certain alkaline environment. Under the action of aeration, most of the ammonia gas in the wastewater can be discharged. Specifically, the aerator 71 is a microporous aerator.

[0035] In fact, in the aeration tank, after the lye and the wastewater are mixed and contacted, a reaction occurs immediately, a large amount of calcium and magnesium ions are released, and calcium-aluminum double-metal hydroxide (CaAl-LDH) is formed. The synergistic effect of the calcium-aluminum double-metal hydroxide (CaAl-LDH) makes the nitrogen and phosphorus in the pig wastewater react to form struvite crystals (MgNH4PO4·6H2O) and calcium-phosphorus (Ca-P) precipitates.

[0036] In some embodiments, the aeration tank 1 is provided with a pH monitoring probe 91 to monitor the change of the pH value of the water body, so as to ensure that the initial pH value of the aeration tank reaction is maintained between 9-10.

[0037] In some embodiments, the liquid level sensor and the pH monitoring probe are connected with the signal receiver, which is convenient for the operator to observe the real-time data.

[0038] In some embodiments, the top of the aeration tank 1 is provided with a tail gas treatment device 11, which can be used to collect harmful gases generated by the reaction. In fact, the ammonia gas generated by the reaction is absorbed by the acidic solution in the tail gas treatment device 11.

[0039] In some embodiments, the top of the aeration tank 1 is provided with an observation port 16, which can be used to observe the operation of the aeration tank. In fact, the space diameter of the observation port 16 is 15-25 cm, which is appropriate. If it is too small, it is not conducive to the observation of maintenance personnel, and if it is too large, it may cause safety hazards such as personnel falling. At the same time, after opening the observation port 16, it cannot be immediately approached to prevent a large amount of ammonia gas and toxic gas from escaping and being absorbed by the human body at the moment of opening.

[0040] In some embodiments, the bottom of the sedimentation tank 2 is provided with a T-shaped discharge port 21, which can separate and discharge the solid product and the liquid product after separation. In fact, the right-angled sludge valve 82 arranged at one end of the T-shaped discharge port 21 can control the discharge of the solid product, and when the liquid product is discharged, the right-angled sludge valve 82 is closed to avoid the liquid product being discharged into the sludge treatment device 12.

[0041] In some embodiments, the reaction time of the aeration tank 1 is 5h, and the sedimentation time of the sedimentation tank 2 is 2h, so that the wastewater in the aeration tank 1 can be completely discharged into the sedimentation tank 2 after the reaction is completed.

[0042] Although the embodiments of the present application have been described in detail above, it is obvious for those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes all belong to the scope and spirit of the present application described in the claims. Moreover, the present application described herein can have other embodiments, and can be implemented or realized in various ways.

Claims

1. An intermittent nitrogen and phosphorus simultaneous recovery device for pig farm wastewater, characterized in that: It comprises a grid pool, a regulating pool, an anaerobic pool, an aeration pool, a tail gas treatment device, a sedimentation pool, a discharge well, a sediment collection device and auxiliary facilities; the auxiliary facilities comprise a dosing device, a diaphragm fan, a pH monitoring probe and a liquid level sensor, a control panel and a signal receiver; The grid pool and the regulating pool are arranged below the ground, the grid pool and the regulating pool are directly connected by a first drain pipe, a sewage lifting pump is arranged between the regulating pool and the anaerobic pool arranged above the ground, the anaerobic pool is closely connected with the aeration pool, a water inlet is formed on the side close to the aeration pool, the aeration pool is arranged on a water platform slightly higher than the ground, a tail gas treatment device is mounted on the top of the aeration pool, the sedimentation pool is arranged above the ground and close to the aeration pool, is connected with the aeration pool through a check valve, a T-shaped discharge port is arranged at the bottom of the sedimentation pool, a right-angle sludge valve and a drain valve are respectively arranged at the two ends of the T-shaped discharge port, a sludge treatment device is arranged below the right-angle sludge valve, and the drain valve is connected with the discharge well through a second drain pipe; The aeration pool is provided with an aeration assembly at the lower end, the aeration assembly comprises an aeration head, a diaphragm fan and an aeration pipe, the diaphragm fan is mounted outside the aeration pool, the aeration pipe is connected with the output end of the diaphragm fan in communication, and the aeration head is arranged on the aeration pipe; The aeration pool is also provided with a pH monitoring probe for monitoring the change of the acidity and alkalinity of the water body, so as to ensure that the aeration pool is in the best reaction acid-base environment; the aeration pool is also provided with a liquid level sensor for monitoring the height of the sewage liquid surface in the aeration pool; the liquid level sensor and the pH monitoring probe are connected with the signal receiver; and the upper end of the aeration pool is provided with an observation port; The dosing device is composed of a dosing barrel, a metering pump and a medicine conveying pipe, and the dosing barrel is connected into the aeration pool through the medicine conveying pipe; The control panel is connected with the information receiver and is used for controlling the operation of each live facility in the system.

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