Rural domestic sewage treatment device and sewage treatment method based on SBR (sequencing batch reactor) process

Abstract

The invention provides a rural domestic sewage treatment device based on an SBR (sequencing batch reactor) process, which is particularly suitable for rural domestic sewage treatment scenes. The invention also provides a method for realizing sewage treatment by using the rural domestic sewage treatment device based on the SBR process. The sewage contact efficiency is improved through the multi-layer staggered sludge purification chamber, and sludge reduction and treatment efficiency maximization are realized in combination with extrusion type sludge discharge and dynamic microorganism addition technologies. The system is suitable for rural distributed sewage treatment scenes, and has the advantages of compact structure, high automation degree, low maintenance cost and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a rural domestic sewage treatment device based on an SBR process, which is particularly suitable for rural domestic sewage treatment scenarios.

[0002] The present invention also relates to a method for treating sewage using a rural domestic sewage treatment device based on the SBR process. Background Art

[0003] With the development of rural economy and the improvement of people's living standards, the discharge of rural domestic sewage has gradually increased, while the construction of sewage treatment facilities has lagged behind, resulting in direct discharge of sewage, which seriously affects the rural environment and residents' health. Therefore, improving the treatment effect of rural domestic sewage has become an urgent problem to be solved. As an efficient and energy-saving sewage treatment technology, SBR (Sequencing Batch Reactor) process has broad application prospects.

[0004] Sequencing batch reactor (SBR) is a very effective process in sewage treatment. In terms of pollutant removal mechanism, SBR is very similar to traditional activated sludge treatment process, but there are big differences in the operation mode of the two. The operation process of traditional activated sludge treatment process is continuous, and sewage flows through different units in the system in turn to realize the treatment process. SBR uses an intermittent treatment process, and sewage enters and exits the system at different time periods. At this time, there is only one unit in the system, and it undertakes different treatment tasks at different times. The complete SBR treatment process includes 5 stages, namely water inlet period, reaction period, sedimentation period, drainage period and idle period. Compared with the traditional activated sludge treatment process, SBR has a simpler structure, smaller equipment space and lower operating costs.

[0005] The SBR process is a relatively mature sewage treatment process. The existing sewage treatment equipment using the SBR process achieves mud-water separation through natural sedimentation. It is difficult to achieve good results in a short period of time. The sedimentation is often insufficient, and the effluent contains mud, resulting in sludge loss and poor effluent effect.

[0006] The sequencing batch activated sludge process (SBR) was developed by Irvine in the United States in the early 1970s. In the early 1980s, the ICEAS process with continuous water inflow appeared. Then Professor Goranzy developed the CASS and CAST processes. In the 1990s, the Belgian SEGHERS company developed the UNITANK system, which combined the time push flow of the classic SBR with the space push flow of the continuous system. my country also began to study SBR in the mid-1980s. It is now widely used.

[0007] The most fundamental characteristic of SBR is that the treatment process is not continuous but intermittent and periodic. The sewage is sequentially fed, aerated, settled, drained and then repeated in batches. The initial SBR process of water intake, aeration, sedimentation, drainage and mud discharge were intermittent. Later, various modifications appeared, some of which changed water intake to continuous, some changed partial aeration to continuous, and some changed water discharge to continuous. However, as long as the characteristics of sequential batch treatment cycle operation are retained, it should belong to the category of SBR process.

[0008] The SBR process is an intermittent reactor. In the SBR process equipment, aeration and non-aeration are operated alternately. Intermittent non-stable biochemical reactions replace steady-state biochemical reactions, eliminating the secondary sedimentation tank of the traditional conventional process. The biological reaction and mud-water separation are completed in one area, so it can save land, have fewer structures and low cost. The SBR process itself is a low-energy, environmentally friendly process that is more suitable for small water volume operation. It can be well promoted in the process of application in rural areas. In particular, the problems of small water volume operation difficulty and scattered sites in rural single-household or several-household sewage projects can be better solved by combining the SBR process with solar power generation.

[0009] The SBR method was used to study actual domestic sewage, and the rapid start-up of short-range nitrification was achieved by alternating anoxic and aerobic operation modes. The SBR reactor was used to treat artificially prepared high-concentration organic sewage, and the effects of different aeration times and aeration volumes on the efficiency of SBR reactors in removing COD from high-concentration organic sewage were explored. The results showed that different aeration times and aeration volumes had a significant effect on the removal efficiency of COD in sewage. When the aeration time was less than 10h, the longer the aeration time, the higher the COD removal rate; in general, the greater the aeration volume, the better the COD removal effect.

[0010] The SBR wastewater treatment process is an activated sludge wastewater treatment technology that operates in an intermittent aeration mode, also known as the sequencing batch activated sludge process. Different from traditional wastewater treatment processes, the SBR technology uses a time-division operation mode instead of a space-division operation mode, a non-stable biochemical reaction instead of a steady-state biochemical reaction, and a static ideal sedimentation instead of a traditional dynamic sedimentation. Its main feature is the orderly and intermittent operation in operation. The core of the SBR technology is the SBR reaction tank, which integrates homogenization, primary sedimentation, biodegradation, secondary sedimentation and other functions in one tank, without a sludge return system.

[0011] The operation mode of SBR consists of five basic stages: water inflow, reaction, sedimentation, water discharge and standby. One cycle is counted from the beginning of wastewater inflow to the end of standby time. In one cycle, all processes are carried out in sequence in a reaction tank equipped with an aeration or stirring device. This operation cycle is repeated over and over to achieve the purpose of continuous wastewater treatment. The SBR process is simple and low in cost.

[0012] The treatment efficiency of traditional SBR wastewater treatment process for total nitrogen is between 60% and 80%. When the total nitrogen content in the wastewater exceeds 250mg / L, after the traditional SBR wastewater treatment, the total nitrogen content of the wastewater will exceed 50mg / L, which does not meet the requirements of the national wastewater discharge standard GB27631-2011. For areas with high land development density, weakened environmental carrying capacity, small water environment capacity, fragile ecological environment, and prone to serious water pollution problems that require special protection measures, the total nitrogen content of the treated wastewater is required to be controlled below 20mg / L. The limitations of the traditional SBR wastewater treatment process are magnified, and its promotion is severely restricted, especially in large and medium-sized cities.

[0013] In view of the shortcomings of low total nitrogen treatment efficiency of traditional SBR wastewater treatment process and different usage purposes, many modified processes have emerged, such as intermittent cycle delayed aeration system (ICEAS process for short), circulating activated sludge system (CASS process for short), circulating activated sludge method (CAST process for short), DAT-IAT process, UNITANK process, etc. These SBR modified processes have solved the shortcomings of traditional SBR process to a certain extent, but either the initial investment cost is too high or the operating cost is high. Summary of the invention

[0014] The object of the present invention is to provide a rural domestic sewage treatment device based on the SBR process to solve the problems raised in the above background technology:

[0015] (1) How to improve the SBR device to achieve low energy consumption, high nitrogen and phosphorus removal efficiency and stable operation, which is particularly suitable for decentralized rural sewage treatment scenarios.

[0016] The object of the present invention is to provide a method for treating sewage using a rural domestic sewage treatment device based on the SBR process to solve the problems raised in the above background technology:

[0017] (1) How to solve the problems of low nitrogen and phosphorus removal efficiency, poor sludge stability and high energy consumption in the traditional SBR process through a microbial-plant symbiotic system.

[0018] To achieve the above object, the present invention provides the following technical solutions:

[0019] A rural domestic sewage treatment device based on SBR process;

[0020] It includes an outer ring reaction tank, a sludge barrel, a sewage pipe, a microbial agent conduit, an extrusion assembly and several sludge purification chambers;

[0021] The outer ring reaction tank is provided with an inner cavity for accommodating sewage, and the outer wall of the outer ring reaction tank is provided with a water inlet and a pressure relief port communicating with the inner cavity;

[0022] The sludge barrel is fixed at the center of the outer ring reaction tank. An opening is provided at the upper end of the sludge barrel. One end of the sewage pipe is connected to the bottom of the sludge barrel, and the other end of the sewage pipe leads to the outside of the outer ring reaction tank. One end of the microbial preparation conduit is also connected to the bottom of the sludge barrel.

[0023] A plurality of sludge purification chambers are located in the inner cavity, and a plurality of sludge purification chambers are fixed beside the sludge barrel. A gap communicating with the inner cavity of the outer ring reaction tank is provided on the surface of the sludge purification chamber, and the sludge purification chamber is also connected to the sludge barrel through a connecting pipe;

[0024] The extrusion assembly includes a press cake and a driving mechanism, the driving mechanism is fixedly connected to the upper side of the outer ring reaction tank, the press cake extends into the sludge barrel from the upper opening of the sludge barrel, the outer contour of the press cake fits the cross-sectional shape of the inner cavity of the sludge barrel, and the driving mechanism drives the press cake to reciprocate along the axial direction of the sludge barrel.

[0025] Based on the above technical solution, the present invention can also be improved as follows.

[0026] Furthermore, the plurality of sludge purification chambers are distributed in three layers along the axial direction of the sludge barrel, and the three layers of sludge purification chambers are arranged alternately.

[0027] Furthermore, the plurality of sludge purification chambers on each layer are evenly distributed in a circle along the axis of the sludge barrel.

[0028] Furthermore, the extrusion assembly also includes a telescopic column, the driving mechanism is a reduction motor, the inner wall of the sludge barrel is provided with threads, the pressed cake and the inner wall of the sludge barrel are threadedly matched, and the reduction motor and the pressed cake are connected and fixed by the telescopic column.

[0029] Furthermore, it also includes an aeration component, which includes an aeration pipeline, an air pump and a plurality of aeration nozzles. The air pump is fixedly connected to the outside of the outer ring reaction tank, the aeration pipeline body is arranged at the bottom of the inner cavity of the outer ring reaction tank, the starting end of the aeration pipeline is connected to the air outlet of the air pump, and the plurality of aeration nozzles are distributed on the aeration pipeline.

[0030] Furthermore, algae are cultivated in the inner cavity of the outer ring reaction tank to facilitate the proliferation of microorganisms.

[0031] After adopting such a structure, the rural domestic sewage treatment device based on the SBR process is mainly composed of water intake, sludge filling, "micro" and "algae" symbiosis, etc. First, the sewage enters the outer ring reaction tank from the water inlet of the outer ring reaction tank. After the outer ring reaction tank is filled, the reduction motor is turned on to provide driving force for the press cake, and the telescopic rod is driven to squeeze the press cake downward to squeeze the sludge. The press cake is tightened with the thread at the bottom of the sludge barrel. During this process, the sewage in the sludge barrel is pressed into the corresponding sludge chamber and stirred, so that it is in a continuous state of motion, forming a dynamic rotating layer, which greatly increases the contact area between the sludge and the air and treatment agents, etc. Increasing the aeration intensity can ensure that more oxygen is dissolved in the sludge to meet the metabolic needs of microorganisms.

[0032] In order to improve the efficiency of activated sludge, the sludge purification chamber is divided into three layers, each layer has eight chambers, and the sludge chambers of each layer are aligned when water is injected to facilitate water injection. When sewage and sludge react, the chambers of each layer are staggered, and the aeration pump is combined to increase the aeration effect; when the activated sludge needs to be replaced, it is after the reaction is completed.

[0033] The external detection unit detects the activated sludge that has played a role in the sludge chamber, and it is squeezed by the pressing component and discharged through the sewage pipe. A part of it flows back to the sludge purification chamber through the sludge barrel for secondary utilization. At the same time, this device will also regularly provide the microorganisms required for sewage purification to the activated sludge layer and the sewage reaction area through the microbial preparation conduit according to the sewage BOD5, COD and other parameters, so as to maintain the activity and working efficiency of the activated sludge.

[0034] After a period of time, when the sewage meets the standards after being tested by the detection unit, the pressure relief valve is opened and the recycled water is discharged for farmland irrigation, etc. Finally, the waste sludge will be transported to the sludge treatment plant and made into bricks for recycling.

[0035] According to the main factors affecting the growth and expansion of microorganisms: pH value, temperature, dissolved oxygen, nutrient solution concentration, growth factors, light, auxiliary conditions, etc., this rural domestic sewage treatment device based on the SBR process can automatically regulate the needs of various indicators to provide a suitable temperature for the growth and working environment of microorganisms and algae; control the pH environment of microorganisms; the air pump is responsible for providing oxygen and carbon dioxide to the inner cylinder to ensure that there is enough dissolved oxygen for microbial expansion. A natural wetland-like treatment is set at the bottom of the outer ring reaction tank. By cultivating algae and other plants that are conducive to the expansion of microorganisms, the two play a symbiotic role, and the stirring effect of the sludge layer greatly increases the expansion rate of microorganisms. The sludge barrel is detachable for regular cleaning and later maintenance.

[0036] To achieve the above object, the present invention also provides the following technical solutions:

[0037] A method for treating sewage using the above-mentioned rural domestic sewage treatment device based on the SBR process comprises the following steps:

[0038] The unpurified rural domestic sewage is input into the inner cavity of the outer ring reaction tank through the water inlet of the outer ring reaction tank. The unpurified rural domestic sewage passes through the inner cavity, the sludge purification chamber, the connecting pipe, and the sludge barrel in sequence until the unpurified rural domestic sewage fills the inner cavity, the sludge purification chamber, the connecting pipe, and the sludge barrel. After standing for one hour, the microbial solution required for sewage purification is transported into the sewage barrel through the microbial preparation conduit, and discharged from the sewage pipe after five hours. During this process, the aeration component inflation pump transports external air to the inner cavity of the outer ring reaction tank through the aeration pipeline and the aeration nozzle;

[0039] Among them, one hour after each injection of the microbial solution required for sewage purification into the sewage barrel through the microbial preparation conduit, the concentration of the microbial solution at the beginning of the microbial preparation conduit is detected. If the concentration of the detected microbial solution is still greater than or equal to half of the concentration measured 10 minutes after the injection of the microbial solution, the extrusion component is started, and the driving mechanism of the extrusion component drives the bottom of the sludge barrel under the press cake to move. The press cake not only squeezes the sludge in the sludge barrel and discharges it from the sewage pipe, but also the movement trajectory of the press cake drives the water flow disturbance in the sludge purification chamber to prevent the sludge and foreign matter from clogging the gap on the surface of the sludge purification chamber.

[0040] The activated sludge in this method utilizes its own microbial metabolism to remove organic pollutants in sewage, such as the biological coagulation, adsorption and oxidation of bacteria, fungi, protozoa and metazoa. The activated sludge has a high water content and good self-coagulation and sedimentation properties, which helps to separate the purified water and waste sludge.

[0041] When sewage and sludge react, each layer of sludge purification chamber is staggered, and each chamber is staggered. Combined with an aeration pump to increase aeration; when the activated sludge needs to be replaced, that is, after the reaction is completed.

[0042] The reduction motor of the extrusion assembly provides thrust for the cake press, which moves upward. The detection unit detects the activated sludge that has already played a role in the sludge purification chamber and automatically outputs it to the sludge barrel, and is discharged through the sludge discharge port on the right side below. A part of it flows back to the sludge layer through the sludge barrel for secondary utilization.

[0043] The beneficial technical effects of the method for sewage treatment using the above-mentioned rural domestic sewage treatment device based on the SBR process are as follows:

[0044] (1) Dynamic contact enhancement: In view of the low treatment efficiency in the sewage treatment process, this device uses a rotating device to keep the sludge in a continuous state of motion to form a dynamic rotating layer. This dynamic sludge layer greatly increases the contact area between the sludge and the air and treatment agents.

[0045] (2) Optimize the microbial environment: This device improves the living environment of microorganisms. The rotating sludge layer creates a more favorable environment for the growth and reproduction of microorganisms. Microorganisms can be better distributed in the dynamic sludge layer, avoiding local overgrowth or undergrowth. At the same time, the mixing effect brought by rotation enables microorganisms to contact more nutrients and substrates, improve their metabolic activity, and thus enhance the effect of sludge treatment.

[0046] (3) Oxygen supply guarantee: In response to the problem of microorganisms' demand for oxygen, this device increases the aeration intensity during the sludge treatment process to ensure that more oxygen is dissolved in the sludge to meet the metabolic needs of the microorganisms.

[0047] (4) Plant-microbe symbiosis: Natural wetland plants can play an important role. Their roots can adsorb and absorb harmful substances in sewage, such as nitrogen, phosphorus and other nutrients, which can effectively reduce eutrophication of water bodies. Plants can also provide habitats for microorganisms.

[0048] (5) Gas stirring effect: In order to avoid the sedimentation of sludge during the treatment process, the device is designed to stir the sludge during the rising process of bubbles generated during the aeration process. This stirring effect can make the sludge more evenly distributed and avoid the situation where the local concentration is too high or too low. At the same time, the stirring of bubbles can also promote the material transfer and heat transfer inside the sludge, making the entire treatment system more stable and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is one of the stereoscopic diagrams of an embodiment of the rural domestic sewage treatment device based on the SBR process.

[0050] Figure 2 This is the second stereoscopic diagram of the embodiment of the rural domestic sewage treatment device based on the SBR process (in order to observe the internal structure of the device more clearly, the side wall of the outer ring reaction tank is omitted in the figure).

[0051] Figure 3 It is a stereoscopic diagram of a sludge barrel, a sewage pipe, a microbial preparation conduit, a sludge purification chamber and an extrusion assembly in an embodiment of the rural domestic sewage treatment device based on the SBR process.

[0052] Figure 4 yes Figure 3 Section view along AA.

[0053] Figure 5 It is a stereoscopic diagram of the aeration component in the embodiment of the rural domestic sewage treatment device based on the SBR process.

[0054] Description of the numbers in the figure:

[0055] Outer ring reaction tank-100; inner cavity-110; water inlet-120; pressure relief port-130; working platform-140; sludge barrel-200; sewage pipe-300; microbial agent conduit-400; sludge purification chamber-500; connecting pipe-510; press cake-610; reduction motor-620; telescopic column-630; plant-700; aeration pipeline-810; air pump-820; aeration nozzle-830. DETAILED DESCRIPTION

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0057] The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementations.

[0058] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0059] See also Figures 1 to 5 .

[0060] The rural domestic sewage treatment device based on the SBR process includes an outer ring reaction tank 100, a sludge barrel 200, a sewage pipe 300, a microbial preparation conduit 400, an extrusion component, an aeration component and twenty-four sludge purification chambers 500.

[0061] An inner cavity 110 for accommodating sewage is provided inside the outer ring reaction tank 100 , and a water inlet 120 and a pressure relief port 130 communicating with the inner cavity 110 are opened on the outer wall of the outer ring reaction tank 100 .

[0062] The sludge barrel 200 is fixed at the center of the outer ring reaction tank 100. An opening is provided at the upper end of the sludge barrel 200. One end of the sewage pipe 300 is connected to the bottom of the sludge barrel 200, and the other end of the sewage pipe 300 leads to the outside of the outer ring reaction tank 100. One end of the microbial preparation conduit 400 is also connected to the bottom of the sludge barrel 200, and the other end of the microbial preparation conduit 400 is connected to an external microbial preparation source.

[0063] The twenty-four sludge purification chambers 500 are all located in the inner cavity 110. All the sludge purification chambers 500 are fixed on the side of the sludge barrel 200. The twenty-four sludge purification chambers 500 are distributed in three layers along the axial direction of the sludge barrel 200. There are eight sludge purification chambers 500 on each layer. The eight sludge purification chambers 500 on each layer are evenly distributed in a circle along the axis of the sludge barrel 200, and the three layers of sludge purification chambers 500 are staggered.

[0064] The surface of the sludge purification chamber 500 is provided with a gap communicating with the inner cavity 110 of the outer ring reaction tank 100 , and the sludge purification chamber 500 is also communicated with the sludge barrel 200 via a connecting pipe 510 .

[0065] The extrusion assembly includes a press cake 610, a telescopic column 630 and a driving mechanism. The driving mechanism is a reduction motor 620, which is welded and fixed on the upper side of the outer ring reaction tank 100. The press cake 610 extends into the sludge barrel 200 from the upper end opening of the sludge barrel 200. The outer contour of the press cake 610 fits the cross-sectional shape of the inner cavity 110 of the sludge barrel 200. The inner wall of the sludge barrel 200 is provided with threads. The press cake 610 and the inner wall of the sludge barrel 200 are threadedly matched. The reduction motor 620 and the press cake 610 are connected and fixed by the telescopic column 630. The telescopic column 630 can be freely extended and retracted along the axial direction of the sewage barrel, and then the reduction motor 620 rotates to drive the press cake 610 to reciprocate along the axial direction of the sludge barrel 200.

[0066] The reduction motor 620 can provide stable rotational power and provide linear movement power for the press cake 610. The extrusion assembly can provide a large thrust, which is suitable for the movement of heavier sludge chamber structures.

[0067] The aeration assembly includes an aeration pipeline 810, an air pump 820 and a plurality of aeration nozzles 830. The air pump 820 is fixedly connected to the outside of the outer ring reaction tank 100. The main body of the aeration pipeline 810 is arranged at the bottom of the inner cavity 110 of the outer ring reaction tank 100. The starting end of the aeration pipeline 810 extends out of the outer ring reaction tank 100 and is connected to the air outlet of the air pump 820. A plurality of aeration nozzles 830 are distributed on the aeration pipeline 810.

[0068] Plants 700 such as algae that are beneficial to the proliferation of microorganisms are also cultivated in the inner cavity 110 of the outer ring reaction tank 100.

[0069] A working platform 140 for personnel to use is also provided on the upper side of the outer ring reaction tank 100 .

[0070] The method for treating sewage using the above-mentioned rural domestic sewage treatment device based on the SBR process comprises the following steps:

[0071] The unpurified rural domestic sewage is input into the inner cavity 110 of the outer ring reaction tank 100 through the water inlet 120 of the outer ring reaction tank 100. The unpurified rural domestic sewage can pass through the inner cavity 110, the sludge purification chamber 500, the connecting pipe 510, and the sludge barrel 200 in sequence until the unpurified rural domestic sewage fills the inner cavity 110, the sludge purification chamber 500, the connecting pipe 510, and the sludge barrel 200. After standing for a certain period of time (for example, one hour later), according to the parameters of sewage BOD5, COD, etc., the microbial solution required for sewage purification is transported into the sewage barrel through the microbial preparation conduit 400, and discharged from the sewage pipe 300 after a certain period of time (for example, five hours later); in this process, the aeration component inflation pump 820 transports external air to the inner cavity 110 of the outer ring reaction tank 100 through the aeration pipeline 810 and the aeration nozzle 830;

[0072] Among them, one hour after each injection of the microbial solution required for sewage purification into the sewage barrel through the microbial agent conduit 400, the concentration of the microbial solution at the starting end of the microbial agent conduit 400 is detected. If the concentration of the detected microbial solution is still greater than or equal to half of the concentration of the microbial solution 10 minutes after injection, it means that the sludge and foreign matter in the sewage barrel and the sludge purification chamber 500 are accumulated, and the extrusion component is started. The driving mechanism of the extrusion component drives the bottom of the sludge barrel 200 under the press cake 610 to move. The press cake 610 not only squeezes the sludge in the sludge barrel 200 and discharges it from the sewage pipe 300, but also the moving trajectory of the press cake 610 drives the water flow disturbance in the sludge purification chamber 500 to prevent the sludge and foreign matter from clogging the gap on the surface of the sludge purification chamber 500.

[0073] To achieve the above complex actions, a precise control system is required. A programmable logic controller (PLC) can be used for control. In PLC programming, different program logics for the water injection stage and the reaction stage are set.

[0074] When water is injected, the PLC sends out instructions and uses sensors (such as position sensors) to feedback whether each chamber is normal. When the signal is received, the water injection operation begins.

[0075] During the reaction stage, the PLC controls the speed and distance of the cake press 610 according to preset parameters and the reaction time and requirements to achieve the best reaction effect.

[0076] Microbial wastewater treatment can automatically adjust the adaptability of microorganisms, and can still achieve good treatment results under different conditions, and the treatment results are stable and reliable. We have also fully improved the reactor volume utilization rate and reduced the complexity of equipment control. Traditional SBR process equipment requires a very high degree of automation. We optimize its control algorithm and logic to enable it to more accurately control various parameters of the reaction pool, such as water level, dissolved oxygen, etc.

[0077] Optimization of water level control algorithm: PID control algorithm can be used. By installing a high-precision water level sensor in the reaction tank, water level data can be obtained in real time. The PID controller calculates the control signal based on the deviation between the set water level value and the actual water level value. In the water injection stage, if the water level is lower than the set value, the water inlet valve opening is increased; if the water level is higher than the set value, the water inlet valve opening is reduced. Similarly, in the drainage stage, precise water level regulation is achieved by controlling the drainage valve. At the same time, the PID parameters are dynamically adjusted. For example, when the water level deviation is large, the proportional coefficient is appropriately increased to speed up the adjustment speed; when approaching the set water level, the proportional coefficient is reduced, and the integral and differential effects are increased to reduce overshoot and oscillation, so that the water level can be more stably maintained at the target value.

[0078] Optimization of dissolved oxygen control logic: On the one hand, a method combining fuzzy control and PID control is adopted. Multiple dissolved oxygen sensors are set in the reaction tank to collect dissolved oxygen data at different locations. The fuzzy controller establishes fuzzy rules based on relevant parameters such as inlet flow, water quality (such as organic matter content, etc.), and temperature, and dynamically adjusts the target value of dissolved oxygen. For example, when the organic matter content of the inlet water is high and the temperature is suitable, the target value of dissolved oxygen is appropriately increased. Then, the PID controller controls the aeration equipment, such as the speed of the aeration fan and the opening of the aeration valve, according to the deviation between the target value output by the fuzzy controller and the actual dissolved oxygen value.

[0079] On the other hand, model predictive control (MPC) is introduced. Based on the dynamic model of the reaction tank, the changing trend of dissolved oxygen in the future is predicted. According to the prediction results, the aeration strategy is adjusted in advance to cope with the fluctuations in the quality and quantity of the influent water and better maintain the dissolved oxygen within the appropriate range. At the same time, combined with real-time data feedback, the model prediction results are corrected, the control strategy is continuously optimized, and the control accuracy is improved.

[0080] The rural domestic sewage treatment device based on the SBR process is used to treat rural domestic sewage, and the parameters of the original sewage are: COD = 350 mg / L, TN = 45 mg / L, TP = 6 mg / L.

[0081] After five hours of operation, the COD removal rate of this rural domestic sewage treatment device based on the SBR process is ≥95%, the TN removal rate is ≥85%, and the TP removal rate is ≥90%, which is 22% lower than the power consumption of the traditional SBR (actual measured data). The microbial solution is added at a rate of 0.5L / m 3 (The microbial solution in this embodiment uses the commercially available microbial sewage treatment strain from Shandong Yuanou Environmental Protection Technology Co., Ltd., model JB-318 biological preparation).

[0082] The above is only one embodiment of the present invention. It should be pointed out that a person skilled in the art may make several modifications and improvements without departing from the principle of the present invention, and these should also be regarded as falling within the scope of protection of the present invention.

Claims

1. A rural domestic sewage treatment device based on SBR process, characterized by: It comprises an outer ring reaction tank (100), a sludge barrel (200), a sewage discharge pipe (300), a microbial preparation conduit (400), an extrusion assembly and a plurality of sludge purification chambers (500); The outer ring reaction tank (100) is provided with an inner cavity (110) for accommodating sewage, and the outer wall of the outer ring reaction tank (100) is provided with a water inlet (120) and a pressure relief port (130) which are in communication with the inner cavity (110); The sludge barrel (200) is fixed at the center of the outer ring reaction tank (100), an opening is provided at the upper end of the sludge barrel (200), one end of the sewage pipe (300) is communicated with the bottom of the sludge barrel (200), the other end of the sewage pipe (300) leads to the outside of the outer ring reaction tank (100), and one end of the microbial preparation conduit (400) is also communicated with the bottom of the sludge barrel (200); A plurality of sludge purification chambers (500) are located in the inner cavity (110), and the plurality of sludge purification chambers (500) are fixed beside the sludge barrel (200). A gap communicating with the inner cavity (110) of the outer ring reaction tank (100) is provided on the surface of the sludge purification chamber (500), and the sludge purification chamber (500) and the sludge barrel (200) are also communicated via a connecting pipe (510); The extrusion assembly comprises a press cake (610) and a driving mechanism, wherein the driving mechanism is fixedly connected to the upper side of the outer ring reaction tank (100), the press cake (610) extends into the sludge barrel (200) from the upper opening of the sludge barrel (200), the outer contour of the press cake (610) fits the cross-sectional shape of the inner cavity (110) of the sludge barrel (200), and the driving mechanism drives the press cake (610) to reciprocate along the axial direction of the sludge barrel (200).

2. The rural domestic sewage treatment device based on the SBR process according to claim 1 is characterized in that: The plurality of sludge purification chambers (500) are distributed in three layers along the axial direction of the sludge barrel (200), and the three layers of sludge purification chambers (500) are arranged in a staggered manner.

3. The rural domestic sewage treatment device based on the SBR process according to claim 2 is characterized in that: The plurality of sludge purification chambers (500) on each layer are evenly distributed in a circle along the axis of the sludge barrel (200).

4. The rural domestic sewage treatment device based on the SBR process according to claim 1 is characterized in that: The extrusion assembly further comprises a telescopic column (630), the driving mechanism is a reduction motor (620), the inner wall of the sludge barrel (200) is provided with threads, the press cake (610) and the inner wall of the sludge barrel (200) are threadedly matched, and the reduction motor (620) and the press cake (610) are connected and fixed via the telescopic column (630).

5. The rural domestic sewage treatment device based on the SBR process according to claim 1 is characterized in that: The invention also includes an aeration component, which includes an aeration pipeline (810), an air pump (820) and a plurality of aeration nozzles (830). The air pump (820) is fixedly connected to the outside of the outer ring reaction tank (100). The main body of the aeration pipeline (810) is arranged at the bottom of the inner cavity (110) of the outer ring reaction tank (100). The starting end of the aeration pipeline (810) is connected to the air outlet of the air pump (820). The plurality of aeration nozzles (830) are distributed on the aeration pipeline (810).

6. The rural domestic sewage treatment device based on the SBR process according to claim 1 is characterized in that: Algae plants (700) that are beneficial to the proliferation of microorganisms are also cultivated in the inner cavity (110) of the outer ring reaction tank (100).

7. A method for treating sewage using the rural domestic sewage treatment device based on the SBR process as described in any one of claims 1 to 6, comprising the following steps: The unpurified rural domestic sewage is introduced into the inner cavity (110) of the outer ring reaction tank (100) through the water inlet (120) of the outer ring reaction tank (100), and the unpurified rural domestic sewage passes through the inner cavity (110), the sludge purification chamber (500), the connecting pipe (510), and the sludge barrel (200) in sequence until the unpurified rural domestic sewage fills the inner cavity (110), the sludge purification chamber (500), the connecting pipe (510), and the sludge barrel (200). After standing for one hour, the microbial solution required for sewage purification is transported into the sewage barrel through the microbial preparation conduit (400), and discharged from the sewage discharge pipe (300) after five hours; During this process, the aeration assembly air pump (820) delivers external air to the inner cavity (110) of the outer ring reaction tank (100) through the aeration pipeline (810) and the aeration nozzle (830); One hour after each injection of the microbial solution required for sewage purification into the sewage barrel through the microbial agent conduit (400), the concentration of the microbial solution at the beginning of the microbial agent conduit (400) is detected. If the concentration of the detected microbial solution is still greater than or equal to half of the concentration measured 10 minutes after the microbial solution is injected, the extrusion component is started, and the driving mechanism of the extrusion component drives the bottom of the sludge barrel (200) under the press cake (610) to move. The press cake (610) not only squeezes the sludge in the sludge barrel (200) and discharges it from the sewage discharge pipe (300), but also the movement trajectory of the press cake (610) drives the water flow in the sludge purification chamber (500) to disturb, thereby preventing the sludge and foreign matter from clogging the gap on the surface of the sludge purification chamber (500).

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