Integrated multistage anaerobic treatment device for high-concentration refractory organic wastewater treatment

Abstract

The utility model discloses an integrated multistage anaerobic treatment device for high concentration refractory organic wastewater treatment. The device comprises water inlet distribution tank, ABR reaction tank, ABR sedimentation tank, anaerobic intermediate tank and UASB reaction tank which are communicated in sequence, and is provided with ABR sludge well. After water inlet is distributed by water inlet distribution tank, it enters ABR reaction tank to carry out multistage anaerobic treatment, and biogas is recovered. After treatment, mixed liquor enters ABR sedimentation tank to carry out sludge and water separation, and sludge is discharged into ABR sludge well, and part can be refluxed to water inlet distribution tank. Supernatant enters anaerobic intermediate tank, is transported to UASB reaction tank by lifting pump and carries out advanced treatment. The two-stage efficient anaerobic process and sludge sedimentation reflux system are integrated in the application, the process flow is compact, the treatment efficiency is high, the anti-impact load capacity is strong, is applicable to the pretreatment of high concentration organic wastewater such as liquor, beer etc.

Description

Technical Field

[0001] The technical field of this utility model is the treatment of high-concentration organic wastewater, and in particular the treatment of organic industrial wastewater in the fields of food processing, pharmaceuticals, textiles, and chemicals. Background Technology

[0002] Many production enterprises in fields such as brewing, food processing, pharmaceuticals, textiles, and chemicals generate high-concentration organic wastewater. This wastewater not only has a high concentration of organic matter and complex composition, but also contains high concentrations of nitrogen and phosphorus, making it difficult to treat. The treatment of this type of wastewater often requires a preliminary anaerobic treatment step to significantly reduce the organic matter content, thereby lowering the organic load and energy consumption of the subsequent aerobic biological treatment stage. Simultaneously, the highly reducing environment of the anaerobic treatment system and the numerous enzymes it contains can act on recalcitrant biodegradable substances (aldehydes, ketones, ethers, aromatic compounds, etc.) and toxic substances (such as chlorobenzene, halogenated hydrocarbons, perchlorinated vinylides, pentachlorophenol, polychlorinated biphenyls, etc.) in the wastewater, enabling them to decompose or partially decompose, altering their structure and biodegradability, and creating conditions for complete degradation in the subsequent aerobic biological treatment stage.

[0003] Anaerobic treatment utilizes the acid-producing and methanogenic processes of anaerobic microorganisms under anaerobic conditions (where there is no free dissolved oxygen or inorganic oxygen ions as oxygen donors) to convert organic matter into biogas (containing 40-70% v / v methane), which is then separated from the liquid phase. Through anaerobic treatment, COD removal can generally reach over 60%. Factors affecting the efficiency of anaerobic treatment include the composition and concentration of organic matter, pH and alkalinity, temperature, residence time, and the type of reactor. Different types of anaerobic reactors can result in variations in anaerobic sludge concentration, microbial aggregation and population types, wastewater-sludge contact methods, sludge age and hydraulic retention time, and biogas collection methods, all of which can impact the stability and efficiency of anaerobic treatment. Traditional anaerobic reactors include completely mixed stirred reactors (CSTRs), upflow anaerobic sludge blanket reactors (UASB reactors), anaerobic baffled reactors (ABR reactors), internal circulation reactors (ICRs), and expanded granular sludge blanket reactors (EGSBs).

[0004] CSTRs typically employ a cylindrical tank design with a small height-to-diameter ratio. They utilize mechanical agitation, with wastewater entering through a distribution pipe at the bottom. A three-phase separation mechanism is located at the top, and the space above the liquid surface serves as a gas storage tank. The top cover can be designed to float vertically and is sealed with a water seal to isolate air. CSTRs are a widely used anaerobic reaction method. The anaerobic reaction zone within the tank is often large, homogeneous, and has a relatively simple microbial community. Wastewater entering the reaction tank is quickly diluted and dispersed throughout the reaction zone, where it ferments under the action of anaerobic sludge, converting into biogas. The reaction device is characterized by its simple structure, strong shock resistance, and stable operation. However, the cylindrical tank design, small height-to-diameter ratio, and long hydraulic retention time result in a relatively large footprint. Mechanical agitation often leads to poor mixing efficiency and high energy consumption. Complete homogenization within the reaction tank is difficult to achieve, and sludge accumulation and dead zones easily form at the bottom.

[0005] An upflow anaerobic sludge blanket reactor (UASB reactor) consists of three parts: a sludge reaction zone, a gas-liquid-solid three-phase separation zone, and a gas chamber. The sludge reaction zone lacks a stirring device, resulting in a high-concentration sludge bed (sludge concentration can even reach 60-80 g / L) at the bottom. This anaerobic reactor is a wastewater biological treatment device that utilizes the high-concentration sludge in the reaction zone to anaerobically treat vertically rising wastewater. Wastewater enters from the bottom of the reactor and flows upward through the sludge bed reaction zone, where most of the organic matter is fermented and converted into biogas. Biogas is continuously released in the form of tiny bubbles. As these bubbles rise, they merge and gradually form larger bubbles. Due to the agitation of the produced gas, a thin sludge suspension layer is formed at the top of the sludge bed. Above this area, sludge, water, and biogas rise together into the three-phase separator. The biogas discharged from the three-phase separator is introduced into the gas chamber through a conduit and can be used as fuel. The separated sludge is returned to the anaerobic reaction zone, causing a large amount of sludge to accumulate in the reaction zone. The treated water, separated from the sludge, overflows from the top of the sedimentation zone overflow weir and is then discharged from the reactor.

[0006] The Anaerobic Baffled Reactor (ABR) is developed based on the Upflow Anaerobic Sludge Blanket Reactor (UASB). It uses a series of vertically installed baffles and partitions to divide the reactor into several reaction chambers connected in series. Each chamber can be considered a relatively independent upflow sludge blanket system. The wastewater being treated flows up and down along the baffles and partitions within the reactor, passing sequentially through the sludge blankets in each chamber. Organic matter in the wastewater is removed through the metabolic activity of anaerobic microorganisms. Utilizing the gases generated within the reactor during treatment, the anaerobic sludge expands and settles within the chambers formed by the baffles. The increased path length of the water flow around the baffles, combined with the obstruction of the baffles and the settling effect of the sludge, effectively retains the anaerobic biological sludge within the reactor. Secondly, the partition walls create independent compartments within the reactor, allowing each compartment to cultivate a microbial community adapted to the different substrates. This separation of the acidogenic and methanogenic phases in the anaerobic reaction results in the anaerobic baffled reactor (ABR) functioning as a two-phase (or two-stage) anaerobic system, achieving phase separation. Furthermore, the ABR allows for the separate emission of biogas from each compartment, preventing the mixing of gases generated at different stages of the anaerobic process. In particular, the H2 produced during acidification can be emitted first, facilitating the smooth conversion of intermediate metabolites such as propionic acid and butyric acid at lower H2 partial pressures during the methanogenic stage.

[0007] In summary, anaerobic baffled reactors (ABR reactors) offer a range of advantages, including simple construction, favorable hydraulic conditions, strong resistance to shock loads, low energy consumption, low cost, and high treatment efficiency. However, ABR reactors also have disadvantages. First, to ensure adequate water flow and gas production velocity, the ABR reactor cannot be too deep. Second, ensuring uniform influent distribution is also a challenge. Furthermore, compared to single-stage upflow anaerobic sludge blanket reactors (UASB reactors), the first chamber of an ABR reactor must withstand a significantly higher local load than the average load, which may lead to a decrease in treatment efficiency. Additionally, dead zones are prone to occur, resulting in a large proportion of ineffective space.

[0008] ICR (Integrated Reactor) is developed based on the Upflow Anaerobic Sludge Blanket Reactor (UASB reactor). It consists of two UASB reactors connected in series, with a gas-solid-liquid three-phase separator at the top of each reactor. Wastewater flows upward through the reactor, passing through two reaction chambers sequentially. Pollutants are adsorbed and degraded by bacteria, and the purified water flows out from the top of the reactor. The biogas produced in the first UASB reactor in the lower layer serves as the internal driving force for the lift, creating a density difference between the mixed liquid in the riser and return pipes, achieving internal circulation of the lower mixed liquid and enhancing the pretreatment of the wastewater. The second UASB reactor in the upper layer performs post-treatment (or fine treatment) of the wastewater, ensuring that the effluent meets the expected treatment requirements. The ICR combines a bottom sludge zone with a middle and upper gas-liquid-solid three-phase separation zone. Through reflux and structural design, the wastewater has a high upward flow velocity in the reaction zone, and the granular sludge inside the reactor is in a suspended and expanded state.

[0009] Expanded granular sludge blanket (EGSB) is an anaerobic bioreactor developed from the upflow anaerobic sludge blanket reactor (UASB). In a sense, it improves upon the UASB in several ways: 1. By improving the influent distribution system, increasing the upward flow velocity of the liquid surface, and enhancing the agitation for biogas production; 2. By designing a larger height-to-diameter ratio; 3. By increasing effluent recirculation to further increase the upward flow velocity of the liquid within the reactor. These improvements result in a significantly higher upward flow velocity than in the UASB, eliminating dead zones and achieving better sludge-water mixing. While the sludge bed in an UASB is more or less like a suspended bed, the EGSB reactor exhibits complete mixing. The EGSB reactor can overcome the shortcomings of upflow anaerobic sludge blanket reactors (UASB reactors), such as short flow, poor mixing effect and sludge loss, while allowing the granular sludge bed to fully expand and enhance the contact between sewage and microorganisms.

[0010] CN 220485500U provides a treatment system for wastewater from Maotai-flavor liquor, including a pretreatment system, an anaerobic treatment system (with a biogas treatment system), a biochemical system, and a deep treatment system. The anaerobic system includes an intermediate tank, an anaerobic reactor, and a sedimentation tank arranged sequentially. A steam diffuser is installed at the bottom of the intermediate tank. The anaerobic reactor is any one of an upflow anaerobic sludge blanket reactor (UASB reactor), an ICR reactor, or an EGSB reactor. The gas outlet of the anaerobic reactor is connected to the inlet of the biogas treatment system, and the outlet of the biogas treatment system is connected to the steam diffuser. A sludge return pipe is installed at the bottom of the sedimentation tank, through which some of the settled sludge is returned to the sludge inlet of the anaerobic reactor. This invention can ensure the temperature of the anaerobic reactor. The sludge return pipe at the bottom of the sedimentation tank can increase the sludge concentration and the upward flow velocity, preventing sludge loss from the anaerobic reactor.

[0011] CN 115925184 B discloses a wastewater treatment process for the brewing industry of Maotai-flavor liquor. The process includes multi-stage screening pretreatment, anaerobic digestion, sludge-water separation, simultaneous ammonia removal, short-cut nitrification, autotrophic biological denitrification, and advanced treatment. The anaerobic digestion process of this invention combines incomplete anaerobic digestion (28-35℃, hydraulic retention time 0.5-2 days) and complete anaerobic digestion (33-40℃, hydraulic retention time 1-4 days) to treat pre-filtered liquids of different concentrations, reducing the volume of the anaerobic digestion tank, lowering energy consumption, and saving construction costs. The wastewater treatment process for the brewing industry provided by this invention has good treatment effect, high ammonia removal efficiency, strong resistance to shock loads, and low operating costs, and has good application prospects.

[0012] CN 216336848U discloses an anaerobic treatment device for wastewater from the brewing of Maotai-flavor liquor, including a first anaerobic tower and a second anaerobic tower, which are connected in parallel or in series. Each of the first and second anaerobic towers, from bottom to top, contains a first water distributor, a first middle sludge reaction zone, a first lower three-phase separator, a first upper sludge reaction zone, and a first upper three-phase separator. Return pipes are also provided in the upper and lower sections. This invention allows for the selection of parallel or series connection of the anaerobic towers based on the influent wastewater concentration. The water distributor is designed as an umbrella-shaped distributor, allowing wastewater with high influent flow rates to flow evenly through the gaps in the umbrella-shaped distributor, ensuring uniform water distribution and preventing clogging. Furthermore, the anaerobic tower of this invention, by incorporating two three-phase separators to create high and low load zones, effectively enhances the anaerobic tower's resistance to shock loads while ensuring stable operation. The invention does not specify the name of its anaerobic reaction device, but its structure is similar to that of IRC or EGSR based on its description.

[0013] CN 114988641 B discloses a method for treating brewing wastewater of Maotai-flavor liquor, including the following steps: 1) Adjusting the pH of the bottom water of the fermentation pit to 14-14.5 and aerating and stirring; 2) Mixing the bottom water of the fermentation pit, the bottom water of the brewing pot, and the production water and sending them into the equalization tank, adjusting the pH to 7.5-8, and then entering the anaerobic treatment; 3) After the anaerobic retention time is 4-5 days, the water enters the two-stage aerobic treatment; 4) The first-stage aerobic treatment adopts MBBR, and the packing material is a plastic hollow suspended ball filled with activated carbon and polyurethane sponge; the second-stage aerobic treatment adopts MBBR process, the packing material is plastic balls, and the effluent enters the deep treatment; 5) The deep treatment adopts advanced oxidation combined with flocculation treatment, and the water is discharged in compliance with standards. This invention employs precise control of the hydraulic retention time of the anaerobic reaction to achieve optimal biodegradability of the anaerobic effluent. By maintaining a stable influent concentration, it ensures the effectiveness of biological treatment while utilizing a two-stage MBBR process to further enhance the shock resistance and load resistance of the wastewater treatment system, thereby improving the treatment effect of high-concentration brewing wastewater and meeting discharge standards. However, this invention does not disclose the type of anaerobic reactor used.

[0014] In addition, existing anaerobic treatment systems often focus on anaerobic digestion and improving the biodegradability of wastewater, while not paying much attention to anaerobic gas production. As a result, the removal rates of COD and BOD are often relatively low.

[0015] Anaerobic methanogenesis systems are dominated by two main microbial communities: acidogenic and methanogenic. While existing anaerobic reactors all promote the growth of these microorganisms and can treat high-concentration organic wastewater, they differ in the types of organic matter they decompose, their tolerance to organic loads, their resistance to shock loads, their pH levels, their gas production efficiency and stability, and the diversity of their microbial communities. Due to the difference in growth rates between acidogenic and methanogenic bacteria, anaerobic methanogenesis systems often experience an imbalance between acid production and methanogenesis, leading to acidification. Different anaerobic reactors also exhibit varying degrees of tolerance to this acidification. While single-unit anaerobic reactors generally have simpler processes and structures, they suffer from poor microbial diversity, susceptibility to shock loads and acidification, and weak capacity to treat recalcitrant organic matter. This is particularly true for industrial organic wastewater containing high concentrations of recalcitrant organic matter with complex compositions; their treatment capacity often falls short of requirements. Furthermore, single-unit anaerobic reactors frequently require long hydraulic retention times, often resulting in sludge deposition, blockages in the inlet and outlet pipes, and operational difficulties. Although ICR and EGSR are equipped with two-layer upflow anaerobic sludge blanket reactors (UASB reactors), forming a two-stage anaerobic treatment system with the second stage used as a so-called fine treatment for enhanced treatment and good treatment effect, such a two-stage treatment system has a high anaerobic treatment tower, which places high demands on the tower structure. At the same time, there is no transition between the two stages of anaerobic treatment, which easily leads to sludge cross-contamination. It is difficult to truly realize the complementary advantages of the two-stage anaerobic treatment system.

[0016] In addition, traditional anaerobic treatment units often require separate large biogas storage tanks and separate sludge sedimentation tanks. These independent treatment structures often have mismatched tank types and need to be connected to each other through pipelines, which results in large equipment footprints and high construction costs.

[0017] In practical applications, there is a need for anaerobic treatment devices that have strong treatment capabilities for various types of organic wastewater, high gas production rate, stable and reliable operation, convenient operation, small footprint, and low construction cost, in order to overcome the shortcomings of existing technologies, reduce the load on subsequent biological treatment systems, and achieve the goal of direct discharge of wastewater. Utility Model Content

[0018] This invention aims to provide a practical, reliable, and efficient anaerobic treatment device for high-concentration organic wastewater. The implementation of this system can be used for the pre-treatment of high-concentration organic wastewater such as liquor brewing wastewater and beer wastewater, reducing the organic load and treatment effect of subsequent decarbonization, denitrification, and phosphorus removal biochemical treatment stages, and saving land and energy consumption.

[0019] To achieve the above objectives, the present invention adopts the following technical solution: An integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater is used for the pre-treatment of high-concentration organic wastewater such as liquor brewing wastewater and beer wastewater, reducing the organic load and treatment effect of subsequent decarbonization, denitrification, and phosphorus removal biochemical treatment stages. It includes an inlet water distribution tank, an anaerobic baffle reactor, an ABR sedimentation tank, an anaerobic intermediate tank, an ABR sludge discharge well, and an upflow anaerobic sludge bed reactor. The water inlet end of the water inlet distribution tank is connected to the main water inlet pipe for introducing wastewater, and the water inlet distribution tank is equipped with several distribution pipes; The water distribution pipe is connected to the anaerobic baffle reactor, which is used for multi-compartment staged anaerobic treatment. The anaerobic baffled reactor is connected to a biogas tank via an ABR biogas exhaust pipe to recover biogas. The outlet end of the anaerobic baffle reactor is connected to an ABR sedimentation tank for separating sludge and clear liquid from wastewater. The lower part of the ABR sedimentation tank is connected to the ABR sludge discharge well through the ABR sedimentation tank sludge collection hopper discharge pipe for collecting sludge; the ABR sludge discharge well uses a sludge pump to discharge sludge into the anaerobic sludge tank through the ABR sludge pump discharge pipe, the ABR residual sludge discharge pipe and the sludge discharge main pipe. The upper part of the ABR sedimentation tank is connected to the anaerobic intermediate tank for collecting the clarified liquid; the clarified liquid is connected to the upflow anaerobic sludge bed reactor through the UASB inlet pipe for further anaerobic treatment. The sludge produced by the upflow anaerobic sludge bed reactor is discharged to the anaerobic sludge tank through the sludge discharge main pipe for sludge treatment; the clear liquid obtained after treatment is discharged into the subsequent treatment device through the main effluent pipe; the biogas obtained after treatment by the upflow anaerobic sludge bed reactor is connected to the biogas tank through the UASB biogas exhaust pipe for biogas recovery.

[0020] Preferably, the anaerobic baffled reactor includes an ABR end guide chamber and at least three ABR compartments. The interior of the ABR end guide chamber has a narrow cavity for receiving wastewater entering from the water distribution pipe and guiding the wastewater to its bottom. The wastewater is sequentially introduced into at least three ABR compartments through the ABR end guide chamber for multi-compartment staged anaerobic treatment, and then introduced into the ABR sedimentation tank for separation of clear liquid and sludge.

[0021] Preferably, the three ABR compartments are a first ABR compartment, a second ABR compartment, and a third ABR compartment; the water distribution pipe is connected to the end guide chamber of the ABR, through which wastewater is introduced into the inlet end of the first ABR compartment; the outlet end of the third ABR compartment is connected to the ABR sedimentation tank; The first ABR compartment, the second ABR compartment, and the third ABR compartment have the same structure and are connected in series. Each ABR compartment is separated by a partition wall, and a gap is left between the partition wall and the bottom of the inner pool of each ABR compartment. Each ABR compartment is vertically equipped with a baffle plate. The space between the baffle plate and the partition wall on the inlet side is defined as the anaerobic reaction chamber. The space between the baffle plate and the partition wall on the outlet side is defined as the internal flow guiding chamber. A gap is left between the top of the baffle plate and the top of the inner tank of the ABR compartment to allow the effluent after passing through the anaerobic reaction chamber to enter the internal flow guiding chamber through the gap at the top of the baffle plate. The anaerobic reaction chamber is equipped with an ABR packing bed. Above and below the ABR packing are a connecting zone and an anaerobic reaction zone, respectively. The anaerobic reaction zone receives liquid introduced from the ABR end guide chamber or the upstream adjacent ABR compartment for anaerobic reaction. The biogas generated from the mixed liquid after reaction enters the ABR packing bed for three-phase separation. The connecting zone is used to introduce the anaerobic treated liquid into the internal guide chamber and through the gap between the partition wall of the internal guide chamber and the bottom of the inner tank, it is introduced into the downstream adjacent ABR compartment. The bottom of the anaerobic reaction zone is a sludge accumulation zone, and the sludge accumulated in the sludge accumulation zone is discharged into the anaerobic sludge tank through the ABR excess sludge discharge pipe.

[0022] Preferably, the ABR sedimentation tank includes a sedimentation inclined tube, the lower part of which is supported by an inclined tube bracket, and the upper part of which is provided with a clear water channel for collecting the sedimented clear liquid; the clear water channel is connected to the anaerobic intermediate tank through a first water passage hole, so as to allow the sedimented clear liquid collected in the clear water channel to be discharged into the anaerobic intermediate tank. The bottom of the ABR sedimentation tank is equipped with a sludge collection hopper, and the lower part of the sludge collection hopper is equipped with an ABR sedimentation tank sludge collection hopper discharge pipe, which is used to discharge the sludge accumulated in the sludge collection hopper into the ABR discharge well.

[0023] Preferably, the anaerobic intermediate tank is equipped with a lift pump to pump the clarified liquid from the ABR sedimentation tank into the upflow anaerobic sludge bed reactor through the UASB inlet pipe for further treatment. Simultaneously, a portion of the clarified liquid is pumped into the distribution tank through the ABR internal return pipe for internal recirculation. This increases the upward flow velocity of wastewater through the ABR sludge bed, preventing anaerobic sludge settling and blockage of the packing bed. It also helps maintain stable pH and alkalinity in the front-end compartments, inhibits the growth of filamentous bacteria when treating protein-containing wastewater, and dilutes toxic and harmful substances in the influent, thereby improving treatment efficiency.

[0024] Preferably, a sludge pump is installed inside the ABR sludge discharge well. The sludge pump is connected to the ABR sludge pump discharge pipe, which is used to discharge sludge into the inlet water distribution tank through the sludge return pipe, and to discharge the remaining sludge into the anaerobic sludge tank for sludge treatment through the ABR remaining sludge discharge pipe. The sludge return allows the ABR front-end compartments to be continuously replenished with acclimated bacteria, maintaining the sludge and effective microbial concentrations in each reaction compartment.

[0025] Preferably, the ABR sludge discharge well is equipped with an air mixing pipe for introducing high-pressure air to mix the sludge in the sludge discharge well.

[0026] Preferably, the UASB inlet pipe is connected to several UASB inlet branch pipes, and the clear liquid in the anaerobic intermediate tank enters the UASB reaction tank through the UASB inlet pipe and several UASB inlet branch pipes; The UASB reactor is equipped with two reactor walls, with the top of the reactor walls connected to the top of the reactor, and a gap between the bottom of the reactor walls and the bottom of the UASB reactor for communication. The space between the two reaction pool retaining walls and the top of the pool forms a UASB gas storage chamber. The space below the UASB gas storage chamber is connected to the UASB reaction pool. The top of the UASB gas storage chamber is provided with a biogas exhaust port for connecting to the UASB biogas exhaust pipe. The UASB biogas exhaust pipe is connected to the biogas tank to recover biogas. Three-phase separation zones are evenly arranged in the space between the outer side of each reaction tank baffle and the tank wall of the UASB reaction tank. Three-phase separator exhaust pipes are respectively opened on the reaction tank baffles on both sides of the UASB gas storage chamber. The three-phase separator exhaust pipes are used to introduce the biogas collected in the three-phase separation zone into the UASB gas storage chamber through the three-phase separator exhaust pipes. Below the three-phase separation zone is the anaerobic reaction zone of the upflow anaerobic sludge bed reactor. The bottom of the UASB reactor is a sludge accumulation zone, which uses several upflow anaerobic sludge bed reactor sludge hoppers. The upper opening of the upflow anaerobic sludge bed reactor sludge hopper is equipped with a UASB sludge hopper discharge pipe, which is used to discharge the sludge accumulated at the bottom of the upflow anaerobic sludge bed reactor sludge hopper into the anaerobic sludge tank for sludge treatment through the sludge discharge main pipe. A water collection channel is provided above the three-phase separation zone. The water collection channel is connected to the UASB main water collection channel through a second water passage provided in the pool wall of the UASB reactor for collecting the effluent. The UASB inlet branch pipe is installed in the sludge hopper of the upflow anaerobic sludge bed reactor through a fixed bracket.

[0027] Preferably, the bottom of the sludge hoppers of several upflow anaerobic sludge bed reactors is provided with sludge hopper connecting pipes in series. The sludge hopper connecting pipes are used to connect the sludge hoppers of different UASB reactors and to distribute the sludge in the sludge hoppers of the upflow anaerobic sludge bed reactors evenly.

[0028] Preferably, the biogas tank includes an ABR biogas storage tank and a UASB biogas storage tank, which are located at the top of the anaerobic baffle reactor and are respectively used to connect the ABR biogas exhaust pipe and the UASB biogas exhaust pipe. The tops of the ABR biogas storage tank and the UASB biogas storage tank are connected by a biogas storage tank connecting pipe, which is connected to the biogas discharge main pipe. The biogas is discharged to the biogas utilization equipment for thermal energy utilization through the biogas discharge main pipe.

[0029] Compared with the prior art, the present invention has the following beneficial effects: This invention addresses the water quality characteristics of high-concentration, recalcitrant organic wastewater by providing an efficient, practical, and reliable anaerobic treatment system that maximizes the effectiveness of anaerobic treatment and reduces the load on subsequent aerobic treatment.

[0030] The combination of an ABR (Anaerobic Batch Reactor) and an upflow anaerobic sludge blanket reactor (UASB reactor) fully leverages the advantages of the ABR, such as its simple structure, low energy consumption, strong resistance to shock loads, and high treatment efficiency, as well as the UASB reactor's high anaerobic sludge concentration, high granular sludge density, short residence time, and excellent treatment effect. Furthermore, the multi-stage reaction structure of the ABR and the granular sludge of the UASB reactor maximize the preservation of microbial diversity in the anaerobic reaction system, achieving separation of acid and methanogenesis while maintaining high organic matter removal efficiency. Following the multi-stage anaerobic reaction of the ABR, the subsequent single-stage UASB reactor further ensures the effective removal of organic matter, recalcitrant and toxic components from the wastewater.

[0031] An ABR intermediate sedimentation tank is installed after the ABR reactor, and internal reflux and sludge recirculation are implemented. The internal reflux increases the flow rate in the ABR reaction zone, increasing the wastewater velocity passing through the anaerobic sludge bed and filter bed. This prevents sludge settling in the sludge bed and sludge clogging in the filter bed. Simultaneously, the alkalinity of the internal reflux liquid is returned to the inlet of the upstream ABR treatment unit, which can replenish the alkalinity in the reactor to a certain extent and dilute the concentration of organic matter and toxic components in the influent, mitigating the impact of wastewater concentration changes on the anaerobic reactor and reducing the influence of toxic components on anaerobic microorganisms. Residual recalcitrant organic matter and microbial metabolic intermediates in the ABR reactor effluent can be re-entered into the reactor for repeated treatment through internal reflux. The ABR sludge recirculation allows for continuous inoculation and replenishment of acclimatized microorganisms in the ABR system, ensuring the maintenance of the dominant microbial community in the system.

[0032] A packing bed is installed above the reaction zone of each reaction compartment in the ABR reactor. This effectively prevents sludge from flowing out of the anaerobic sludge bed and facilitates three-phase separation of gas, liquid, and solid, eliminating the need for a three-phase separator, simplifying the device and reducing its height.

[0033] The upflow anaerobic sludge blanket reactor (UASB reactor) of this invention adopts a rectangular tank shape and a horizontal design with a small height-to-width ratio. The UASB gas storage chamber is arranged in the middle, which reduces the height of the upflow anaerobic sludge blanket reactor (UASB reactor), which is conducive to maintaining the elevation matching with the ABR and reducing the energy consumption required for hydraulic lifting.

[0034] This invention combines an ABR (Automatic Bioreactor) and an upflow anaerobic sludge blanket reactor (UASB reactor), eliminating the need for a sedimentation tank downstream of the UASB reactor. The low sludge production characteristic of the UASB reactor, along with the three-phase separator installed within the UASB reactor's internal space, ensures adequate sludge settling in the effluent, preventing sludge runoff in the effluent.

[0035] The integrated modular design, which integrates multiple structures into a single rectangular space, can greatly reduce the footprint of the structures, eliminate the need for connecting pipes between equipment rooms, and save on construction costs. Attached Figure Description

[0036] Figure 1 A top view schematic diagram of an integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater, provided as an embodiment of this utility model; Figure 2 for Figure 1 A schematic diagram of the AA structure in the diagram; Figure 3 for Figure 1 A schematic diagram of the BB structure in the image; Figure 4 for Figure 1 A schematic diagram of the CC structure in the diagram; Figure 5 for Figure 1 A schematic diagram of the DD structure in the diagram; Figure 6 for Figure 1 A schematic diagram of the EE structure in the diagram; Figure 7 for Figure 1 A schematic diagram of the FF structure in the image; Figure 8 for Figure 1 A schematic diagram of the GG structure in the image.

[0037] The serial numbers in the diagram are as follows: 1. Inlet water distribution tank; 1-1. Water distribution pipe; 2. ABR end guide chamber; 3-1. First ABR compartment; 3-1-1. First ABR packing support; 3-1-2. First ABR packing bed; 3-1-3. First ABR packing pressure plate; 3-1-4. First ABR sludge discharge pipe; 3-2. Second ABR compartment; 3-2-1. Second ABR packing support; 3-2-2. Second ABR packing bed; 3-2-3. Second ABR packing pressure plate; 3-2-4. Second ABR... 3-3, Third ABR Compartment; 3-3-1, Third ABR Packing Support; 3-3-2, Third ABR Packing Bed; 3-3-3, Third ABR Packing Pressure Plate; 3-3-4, Third ABR Sludge Discharge Pipe; 4, ABR Sedimentation Tank; 4-1, Sedimentation Inclined Tube Support; 4-2, Sedimentation Inclined Tube; 4-3, Clear Water Channel; 4-4, First Water Passage Hole; 4-5, Sludge Hopper; 4-6, ABR Sedimentation Tank Sludge Hopper Sludge Discharge Pipe; 5, Anaerobic Intermediate Tank; 5-1, Lifting Pump; 6, ABR Discharge... 6-1 Sludge well; 6-2 Sludge pump discharge pipe; 7 UASB reactor; 7-1 Water collection channel; 7-2 Three-phase separation zone; 7-3 Three-phase separator exhaust pipe; 7-4 Second water passage; 7-5 Inlet pipe fixing bracket; 7-6 Sludge hopper connecting pipe; 7-7 UASB sludge hopper discharge pipe; 8 UASB gas storage chamber; 9 UASB main water collection channel; 10 Main inlet pipe; 11 Main outlet pipe; 12 UASB inlet pipe; 12-1 UASB inlet branch pipe ; 13. ABR internal return pipe; 14. ABR biogas exhaust pipe; 15. UASB biogas exhaust pipe; 16-1. ABR biogas storage tank; 16-2. UASB biogas storage tank; 17. Biogas storage tank connecting pipe; 18. Biogas exhaust main pipe; 19. ABR sludge discharge well mixing air pipe; 20. ABR sludge pump sludge discharge pipe; 21. ABR sludge return pipe; 22. ABR residual sludge discharge pipe; 23. First partition wall; 24. Second partition wall; 25. Third partition wall; 26. Fourth partition wall. Detailed Implementation

[0038] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0039] like Figures 1 to 8 As shown, this embodiment provides an integrated multi-stage anaerobic treatment device that combines an anaerobic baffled reactor (ABR reactor) and an upflow anaerobic sludge blanket reactor (UASB reactor). Figure 2-8 These correspond to the schematic diagrams of cross-sections AA, BB, CC, DD, EE, FF, and GG, respectively.

[0040] Specifically, it consists of the following parts: inlet water distribution tank, ABR reactor, ABR sedimentation tank, anaerobic intermediate tank, ABR sludge discharge well, UASB reactor, and biogas storage tank.

[0041] This treatment unit adopts an integrated design. Except for the inlet water distribution tank and biogas storage tank, all major structures are integrated into a single rectangular structure. The tops of the anaerobic treatment units are covered to isolate them from air. Adjacent treatment units are separated by tank walls. Treatment structures connected sequentially according to the treatment process flow are linked by openings in the partition walls or by water passages within the partition walls. The flow of wastewater from the inlet to the final collection channel is driven by gravity and a booster pump. The inlet water distribution tank and biogas storage tank are located on the top of the integrated tank.

[0042] This processing device can combine two or three of the above-mentioned processing devices in parallel for handling situations with large flow rates, and can also perform flow rate allocation and equipment maintenance more flexibly.

[0043] The inlet water distribution tank 1 is rectangular in shape and is located on top of the ABR reactor. It is equipped with a main inlet pipe 10 connection port, an ABR sludge return pipe 21 connection port, an ABR internal return pipe 13 connection port, and a distribution pipe 1-1 connection port. The number of distribution pipes 1-1 is determined according to the treatment water volume and the width of the tank. The distribution pipes 1-1 connect the water distribution tank 1 to the ABR end guide chamber 2 of the ABR reactor.

[0044] The ABR reactor is internally divided into an ABR end diversion chamber 2, a first ABR compartment 3-1, a second ABR compartment 3-2, and a third ABR compartment 3-3. The second and third ABR compartments 3-2 and the first ABR compartment 3-1 have similar internal structures, are rectangular in plan, and are arranged in series. The ABR end diversion chamber 2 is separated from the first ABR compartment 3-1 by a first partition wall 23. The first ABR compartment 3-1 is separated from the ABR end diversion chamber 2 by a second partition wall 24. The second ABR compartment 3-2 is separated from the third ABR compartment 3-1 by a third partition wall 25. The third ABR compartment 3-3 is separated from the ABR sedimentation tank 4, the anaerobic intermediate tank 5, and the ABR sludge well 6 by a fourth partition wall 26. There is a gap between the first partition wall 23 and the bottom of the inner tank of the first ABR compartment 3-1; there is a gap between the second partition wall 24 and the bottom of the inner tank of the second ABR compartment 3-2; there is a gap between the third partition wall 25 and the bottom of the inner tank of the third ABR compartment 3-3; and there is a gap between the bottom of the inner tank of the fourth partition wall 26 and the ABR sedimentation tank 4.

[0045] Water distribution pipe 1-1 is connected to the ABR end guide chamber 2, through which wastewater is introduced into the inlet end of the first ABR compartment 3-1; the outlet end of the third ABR compartment 3-3 is connected to the ABR sedimentation tank 4.

[0046] The ABR end guide chamber 2 is a narrow cavity with a rectangular planar shape, used to receive wastewater entering from the water distribution pipe 1-1, so that the ABR end guide chamber 2 is connected to the bottom of the first ABR compartment 3-1.

[0047] Wastewater flows from the distribution pipe 1-1 into the ABR end guide chamber 2. There is a gap at the bottom of the partition wall between the ABR end guide chamber 2 and the first ABR compartment 3-1 so that the wastewater can enter the first ABR compartment 3-1 from the bottom through the gap.

[0048] The first ABR compartment 3-1 is vertically equipped with a first baffle plate. The space between the first baffle plate and the first partition wall 23 is defined as the first anaerobic reaction chamber, and the space between the first baffle plate and the second partition wall 24 is defined as the first internal flow guiding chamber.

[0049] The first ABR packing bed 3-1-2 is set in the middle of the first anaerobic reaction chamber; the first connecting zone and the first anaerobic reaction zone are located above and below the first ABR packing bed 3-1-2, respectively. The liquid in the lower part of the ABR end guide chamber 2 is introduced into the first anaerobic reaction zone through the gap at the bottom of the first partition wall 23 for anaerobic reaction. After the reaction, the mixed liquid and the generated biogas enter the first ABR packing bed 3-1-2 for three-phase separation.

[0050] The top of the first baffle plate has a gap with the top of the inner tank of the first ABR compartment 3-1, forming a first connecting area. It communicates with the first internal flow guide chamber through the gap, which is used to introduce the outflow of the first anaerobic reaction chamber from the upper part of the inner tank of the first ABR compartment 3-1 into the first internal flow guide chamber. The first internal flow guide chamber introduces the outflow from the bottom into the second ABR compartment 3-2 through the gap at the bottom of the second partition wall 24.

[0051] The second ABR compartment 3-2 is vertically equipped with a second baffle plate. The area between the second baffle plate and the second partition wall 24 is defined as the second anaerobic reaction chamber, and the area between the second baffle plate and the third partition wall 25 is defined as the second internal flow guiding chamber.

[0052] The second anaerobic reaction chamber has a second ABR packing bed 3-2-2 in the middle; the upper and lower parts of the second ABR packing bed 3-2-2 are the second connecting zone and the second anaerobic reaction zone, respectively. The liquid in the lower part of the first internal guide chamber is introduced into the second anaerobic reaction zone through the gap at the bottom of the second partition wall 24 for anaerobic reaction. After the reaction, the mixed liquid and the biogas produced enter the second ABR packing bed 3-2-2 for three-phase separation.

[0053] The top of the second baffle plate has a gap with the top of the inner tank of the second ABR compartment 3-2 to form a second communication zone. It communicates with the second internal flow guide chamber through the gap, so as to introduce the outflow of the second anaerobic reaction chamber from the upper part of the inner tank of the second ABR compartment 3-2 into the second internal flow guide chamber. The second internal flow guide chamber introduces the outflow from the bottom of the third partition wall 25 into the third ABR compartment 3-3 from the bottom.

[0054] The third ABR compartment 3-3 is vertically equipped with a third baffle plate. The area between the third baffle plate and the third partition wall 24 is defined as the third anaerobic reaction chamber, and the area between the third baffle plate and the third partition wall 25 is defined as the third internal flow guiding chamber.

[0055] The third ABR packing bed 3-3-2 is located in the middle of the third anaerobic reaction chamber; the third connecting zone and the third anaerobic reaction zone are located above and below the third ABR packing bed 3-3-2, respectively. The fluid in the lower part of the second internal guide chamber is introduced into the third anaerobic reaction zone through the gap at the bottom of the third partition wall 25 for anaerobic reaction. After the reaction, the mixed liquid and the biogas produced enter the third ABR packing bed 3-3-2 for three-phase separation.

[0056] The top of the third baffle plate and the top of the inner tank of the third ABR compartment 3-3 are separated to form the third connecting zone. The third connecting zone is connected to the third internal flow guiding chamber through the gap. The outflow of the third anaerobic reaction chamber is introduced from the upper part of the inner tank of the third ABR compartment 3-3 into the third internal flow guiding chamber. The third internal flow guiding chamber is introduced from the bottom into the ABR sedimentation tank 4 through the gap at the bottom of the fourth partition wall 26.

[0057] The third ABR compartment 3-3 is adjacent to the ABR sedimentation tank 4, the anaerobic intermediate tank 5, and the ABR sludge discharge well 6 on one side. In addition, more than 3 ABR compartments can be set up as needed.

[0058] The bottom of the first ABR packing bed 3-1-2 is equipped with a packing support 3-1-1 for mounting it on the upper part of the anaerobic reaction chamber within the first ABR compartment 3-1. A first packing pressure plate 3-1-3 is located on its top to restrict the flow of filter media with the water flow. A biogas vent is located on the top of the tank above the first ABR packing bed 3-1-2 for connecting to the ABR biogas vent pipe 14. Below the first ABR packing bed 3-1-2 are the sludge reaction zone and sludge storage zone. A first sludge discharge pipe 3-1-4 is located below the sludge bed zone.

[0059] The second ABR packing bed 3-2-2 has a second packing support 3-2-1 at its bottom for installation in the upper part of the anaerobic reaction chamber within the second ABR compartment 3-2. A second packing pressure plate 3-2-3 at its top restricts the flow of filter media with the water flow. A biogas vent is located on the top of the tank above the second ABR packing bed 3-2-2 for connecting to the ABR biogas vent pipe 14. Below the second ABR packing bed 3-2-2 are the sludge reaction zone and sludge storage zone. A second sludge discharge pipe 3-2-4 is located below the sludge bed zone.

[0060] The bottom of the third ABR packing bed 3-3-2 is equipped with a third packing support 3-3-1 for mounting it on the upper part of the anaerobic reaction chamber within the third ABR compartment 3-3. A packing pressure plate 3-3-3 is located on top of the support to restrict the filter media's flow with the water. A biogas vent is located on the top of the tank above the third ABR packing bed 3-3-2 for connecting to the ABR biogas vent pipe 14. Below the third ABR packing bed 3-3-2 are the sludge reaction zone and sludge storage zone. A third sludge discharge pipe 3-3-4 is located below the sludge bed zone.

[0061] The ABR sedimentation tank 4 has a rectangular plan shape and an inclined sedimentation tube 4-2 in the middle. An inclined tube support 4-1 is provided at the bottom of the inclined tube 4-2 to support the inclined tube. A clear water channel 4-3 is provided at the top of the sedimentation tank to collect the precipitated clear liquid. A first water passage 4-4 is provided in the partition wall between the clear water channel 4-3 and the anaerobic intermediate tank 5 so that the precipitated clear liquid in the clear water channel 4-3 can be discharged into the anaerobic intermediate tank 5. A sludge collection hopper 4-5 is provided at the bottom of the ABR sedimentation tank 4-5. A sludge discharge pipe 4-6 is provided at the bottom of the sludge collection hopper 4-5 to discharge the sludge accumulated at the bottom into the ABR sludge discharge well 6.

[0062] The anaerobic intermediate tank 5 has a rectangular plan shape and is equipped with a lift pump 5-1. This pump pumps the clarified liquid from the ABR sedimentation tank into the upflow anaerobic sludge blanket reactor (UASB reactor) via the UASB inlet pipe 12 for further treatment. Simultaneously, a portion of the clarified liquid is pumped into the distribution tank 1 via the ABR internal return pipe 13 for internal recirculation. This internal recirculation increases the upward flow velocity of wastewater through the ABR sludge blanket, preventing anaerobic sludge settling and blockage of the packing bed. Furthermore, appropriate recirculation helps maintain stable pH and alkalinity in the upstream compartments and can inhibit the growth of filamentous bacteria when treating certain protein-containing wastewaters, diluting toxic and harmful substances in the influent and thus improving treatment efficiency.

[0063] The ABR sludge discharge well 6 has a rectangular plan shape and houses a sludge pump 6-1. The sludge pump 6-1 is connected to the ABR sludge pump discharge pipe 20, used to discharge sludge into the influent distribution tank 1 through the sludge return pipe 21, and to discharge excess sludge into the anaerobic sludge tank for treatment through the ABR excess sludge discharge pipe 22 and the main discharge pipe. The sludge return system allows for the continuous replenishment of acclimated microorganisms to the ABR front-end compartments, maintaining the sludge and effective microbial concentrations in each reaction compartment. The ABR sludge discharge well 6 is equipped with a stirring air pipe 19, used to introduce high-pressure air to agitate the sludge within the well.

[0064] The UASB reactor 7 has a rectangular plan shape and is equipped with two retaining walls inside. A gap is left between the lower part of the retaining walls and the bottom of the reactor to allow the lower part of the entire UASB reactor to be connected. The top of the retaining walls connects to the top of the reactor, forming a UASB gas storage chamber 8 between the two retaining walls and the top of the reactor. The top of the UASB gas storage chamber 8 has a biogas exhaust port for connecting to the UASB biogas exhaust pipe 15. The space below the UASB gas storage chamber 8 is interconnected with other spaces in the UASB reactor 7. A three-phase separation zone 7-2 is arranged in the space between the outer side of each retaining wall and the reactor wall of the UASB reactor 7. A three-phase separator exhaust pipe 7-3 is installed within the wall of the retaining wall within the three-phase separation zone, allowing the biogas collected by the three-phase separator to enter the UASB gas storage chamber 8 through the three-phase separator exhaust pipe 7-3. A water collection channel 7-1 is set in the clear water area above the three-phase separation zone 7-2. The water collection channel 7-1 is connected to the UASB main water collection channel 9 through a second water passage 7-4 set inside the reactor wall. Below the three-phase separation zone 7-2 is the anaerobic reaction zone. A sludge hopper is installed at the bottom of the tank. Inside the sludge hopper, there is a UASB inlet branch pipe 12-1 inlet pipe fixing bracket 7-5. A sludge hopper connecting pipe 7-6 is installed at the bottom of the sludge hopper partition to connect different sludge hoppers. A UASB sludge hopper discharge pipe 7-7 is installed at the top of the sludge hopper to discharge the sludge accumulated at the bottom into the anaerobic sludge tank for sludge treatment through the sludge main pipe.

[0065] An ABR biogas storage tank 16-1 and a UASB biogas storage tank 16-2 are installed at the top of the ABR reactor. These tanks are equipped with interfaces for connecting the ABR biogas exhaust pipe 14 and the UASB biogas exhaust pipe 15, respectively. The tops of the ABR biogas storage tank 16-1 and the UASB biogas storage tank 16-2 are connected by a biogas storage tank connecting pipe 17, which is connected to a biogas exhaust manifold 18. The biogas exhaust manifold is used to discharge biogas to biogas utilization equipment for thermal energy utilization.

[0066] The working principle of this utility model is as follows: After the raw wastewater is regulated in terms of flow rate and concentration in the equalization tank, it enters the inlet distribution tank 1 located on the top of the integrated structure tank through the main inlet pipe 10. It is fully mixed with the ABR internal return liquid and ABR return sludge that enter the distribution tank through the internal return pipe 13 and the return sludge pipe 21. The mixture is then evenly distributed to the inlet section of the ABR end guide chamber 2 of the ABR reactor through the distribution pipe 1-1. The wastewater then enters the first ABR compartment 3-1 through the connecting area at the bottom of the ABR end guide chamber 2 for primary anaerobic reaction.

[0067] Wastewater in the first anaerobic reaction chamber of the first ABR compartment 3-1 reacts with anaerobic sludge from bottom to top in the ABR anaerobic reaction zone, producing biogas. The biogas and wastewater then enter the sludge-water-gas three-phase separation zone formed by the ABR packing bed. In the three-phase separation zone, the sludge falls back into the anaerobic reaction zone under gravity. When the sludge concentration in the anaerobic reaction zone reaches a certain level, some sludge settles into the sludge accumulation zone at the bottom of the tank and is discharged to the anaerobic sludge tank for sludge treatment through the ABR sludge discharge pipe 3-1-4 and the main sludge discharge pipe. The generated biogas is discharged from the liquid and enters the upper space for storage, then discharged into the ABR biogas storage tank 16-1 through the ABR biogas discharge pipe 14, and discharged externally through the biogas storage tank connecting pipe 17 and the biogas discharge main pipe 18 for biogas utilization. The mixed liquid after biogas discharge enters the first internal diversion chamber from the top and then enters the second ABR compartment 3-2 from the bottom of the first internal diversion chamber for secondary anaerobic reaction.

[0068] Wastewater undergoes the same reaction as in the first ABR compartment 3-1 in the second ABR compartment 3-2 and subsequently in the third ABR compartment 3-3, and then enters the inlet area of ​​the ABR sedimentation tank 4 through the connection port under the partition wall between the third ABR compartment 3-3 and the ABR sedimentation tank 4.

[0069] After entering the inlet area of ​​ABR sedimentation tank 4, the wastewater flows upward, passes through the sedimentation inclined tube 4-2, then enters the upper clear water area, and flows into the clear water channel 4-3. It then passes through the first water passage 4-4 of the clear water channel and enters the anaerobic intermediate tank 5. The settled sludge inside the sedimentation inclined tube 4-2 slides down and accumulates in the sludge collection hopper 4-5 at the bottom of the tank. It then flows through the ABR sedimentation tank sludge discharge pipe 4-6 at the bottom of the sludge collection hopper into the ABR sludge discharge well 6.

[0070] After entering the ABR sludge discharge well 6, the sludge is sent to the inlet water distribution tank 1 for sludge return via sludge pump 6-1, ABR sludge pump discharge pipe 20, and sludge return pipe 21. The remaining sludge, as surplus sludge, is discharged to the anaerobic sludge tank for treatment via ABR surplus sludge discharge pipe 22 and the main discharge pipe. A certain amount of compressed air is introduced into the ABR sludge discharge well 6 through the ABR sludge discharge well stirring air pipe 19 to agitate the sludge in the discharge well and prevent sludge sedimentation.

[0071] A portion of the sediment from the anaerobic intermediate tank 5 enters the anaerobic reaction zone of the UASB reactor 7 via the lift pump 5-1, UASB inlet pipe 12, and UASB inlet branch pipe 12-1 for further anaerobic treatment. The other portion is returned to the inlet distribution tank 1 via the ABR internal return pipe 13. The internal return setting of the ABR increases the flow rate and velocity through the anaerobic reaction zone of the ABR, and increases the flow velocity of wastewater through the filter media layer, preventing sludge settling in the anaerobic reaction zone and sludge blockage in the packing area. At the same time, it can dilute the concentration of organic matter and components toxic to microorganisms in the influent, which is conducive to maintaining a stable pH and alkalinity in the front-end ABR compartment.

[0072] Wastewater entering the anaerobic reaction zone of UASB reactor 7 sequentially passes through the anaerobic sludge bed, the three-phase separation zone 7-2, the clear liquid zone, and then enters the upper collection channel 7-1. It then flows through the second water passage 7-4 into the UASB main collection channel 9, and from there into the main outlet pipe 11, proceeding to subsequent treatment facilities. The three-phase separation zone 7-2 contains a three-phase separator. The separated gas accumulates at the top of the separator and enters the UASB gas storage chamber 8 through the three-phase separator exhaust pipe 7-3. It then flows through the UASB biogas exhaust pipe 15 into the UASB biogas storage tank 16-2, and finally is discharged externally through the ABR and UASB biogas storage tank connecting pipe 17 and the biogas discharge main pipe 18 for biogas utilization. The sludge separated in the three-phase separation zone 7-2 accumulates to a certain extent and then slides down, accumulating in the sludge hopper at the bottom. It is then discharged externally to the anaerobic sludge tank for sludge treatment through the UASB sludge hopper discharge pipe 7-7 and the main discharge pipe. The bottom of the sludge hopper is equipped with a sludge hopper connecting pipe 7-6, which is used to connect different sludge hoppers.

[0073] The following is a detailed explanation using specific data: A certain Maotai-flavor liquor brewing enterprise generates a total of 6000 m³ of production wastewater and domestic sewage from its auxiliary living facilities during the brewing process. 3 / d.

[0074] After being mixed and having its flow and concentration adjusted in the equalization tank, the wastewater enters the inlet distribution tank 1 located on the top of the integrated structure tank through the main inlet pipe 10. It is then evenly distributed to the inlet section of the ABR end guide chamber 2 of the ABR reactor through the distribution pipe 1-1. The wastewater then enters the first ABR compartment 3-1 through the connecting area at the bottom of the ABR end guide chamber 2 for primary anaerobic reaction.

[0075] Wastewater in the first anaerobic reaction chamber of the first ABR compartment 3-1 passes through the anaerobic reaction zone and the ABR packing bed from bottom to top, reacting with anaerobic sludge and producing biogas. The ABR packing bed plays a role in three-phase separation to a certain extent; sludge is retained in the packing bed, while some sludge falls from the packing zone into the anaerobic reaction zone. After sludge accumulates to a certain extent in the anaerobic reaction zone, some settles into the sludge accumulation zone at the bottom of the tank and is discharged into the anaerobic sludge tank for sludge treatment through the sludge discharge pipe 3-1-4 and the sludge main pipe. The generated biogas is discharged from the liquid and enters the upper space for storage, and is discharged into the ABR biogas storage tank 16-1 through the ABR biogas exhaust pipe 14, and then discharged externally through the biogas storage tank connecting pipe 17 and the discharge main pipe 18 for biogas utilization. The mixed liquid after biogas discharge enters the internal guide chamber from the connecting area above the reaction chamber, and then enters the second ABR compartment 3-2 from the bottom of the internal guide chamber for secondary anaerobic reaction.

[0076] Wastewater undergoes the same reaction as in the first ABR compartment in the second ABR compartment 3-2 and subsequently in the third ABR compartment 3-3, and then enters the inlet area of ​​the ABR sedimentation tank 4 through the connection port under the partition wall between the third ABR compartment 3-3 and the ABR sedimentation tank 4.

[0077] After entering the inlet area of ​​ABR sedimentation tank 4, the wastewater flows upward, passes through the sedimentation inclined tube 4-2, then enters the upper clear water area, and flows into the clear water channel 4-3. It then passes through the first water passage 4-4 of the clear water channel and enters the anaerobic intermediate tank 5. The settled sludge inside the sedimentation inclined tube 4-2 will slide down on its own, settle, and accumulate in the sludge collection hopper 4-5 at the bottom of the tank. It then flows through the ABR sedimentation tank sludge discharge pipe 4-6 at the bottom of the sludge collection hopper into the ABR sludge discharge well 6.

[0078] After entering the ABR sludge discharge well 6, the sludge is pumped into the inlet water distribution tank 1 via sludge pump 6-1, ABR sludge pump discharge pipe 20, and sludge return pipe 21 for sludge return. Sludge return allows for continuous inoculation and replenishment of acclimation microorganisms in the ABR reaction system, ensuring the maintenance of the dominant microbial community in the system. The remaining sludge, as surplus sludge, is discharged to the anaerobic sludge tank for treatment via ABR surplus sludge discharge pipe 22 and the main discharge pipe. A certain amount of compressed air is introduced into the sludge discharge well 6 through the ABR sludge discharge well stirring air pipe 19 to agitate the sludge in the sludge discharge well 6 and prevent sludge sedimentation.

[0079] Part of the precipitated clear liquid entering the anaerobic intermediate tank 5 is fed into the anaerobic reaction zone of the UASB reactor 7 via the lift pump 5-1, UASB inlet pipe 12, and UASB inlet branch pipe 12-1 for further anaerobic treatment. The other part is fed into the inlet water distribution tank 1 via the ABR internal return pipe 13 for return and circulation. The internal return setting of the ABR can increase the flow rate and velocity through the anaerobic reaction zone of the ABR, prevent sludge settling in the anaerobic sludge bed and sludge blockage in the packing bed, and dilute the concentration of organic matter and toxic and harmful components in the inlet water, maintaining the stability of pH and alkalinity in the upstream ABR compartment.

[0080] Wastewater entering the anaerobic reaction zone of UASB reactor 7 sequentially passes through the anaerobic sludge bed, the three-phase separation zone 7-2, and the clear liquid zone, before entering the upper collection channel 7-1. It then flows through the second water passage 7-4 into the UASB main collection channel 9, and from there into the main outlet pipe 11, proceeding to subsequent treatment facilities for further processing. The gas separated by the three-phase separator in the three-phase separation zone 7-2 accumulates at the top of the separator and enters the UASB gas storage chamber 8 through the three-phase separator exhaust pipe 7-3. It is then discharged into the UASB biogas storage tank 16-2 through the UASB biogas exhaust pipe 15, and finally discharged externally through the ABR and UASB biogas storage tank connecting pipe 17 and the biogas discharge main pipe 18 for biogas utilization. The sludge separated by the three-phase separator accumulates to a certain extent and slides down, accumulating in the sludge hopper at the bottom. It is then discharged externally to the anaerobic sludge pond through the UASB sludge hopper discharge pipe 7-7 for sludge treatment.

[0081] Through the above anaerobic treatment, COD and BOD in the liquor brewing wastewater are effectively treated, and ammonia nitrogen (NH3-N), total nitrogen (TN), total phosphorus (TP), and color are treated to a certain extent, greatly reducing the treatment load of subsequent aerobic treatment.

[0082] Table 1. Water quality indicators of the influent and effluent of the treatment device in this embodiment.

[0083] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0084] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0085] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater, used for pre-treatment of high-concentration organic wastewater such as liquor brewing wastewater and beer wastewater, reducing the organic load and treatment efficiency of subsequent decarbonization, denitrification, and phosphorus removal biochemical treatment stages, characterized in that... It includes an inlet water distribution tank (1), an ABR reactor, an ABR sedimentation tank (4), an anaerobic intermediate tank (5), an ABR sludge discharge well (6), and a UASB reactor (7). The water inlet end of the water inlet distribution tank (1) is connected to the main water inlet pipe (10) for introducing wastewater. The water inlet distribution tank (1) is provided with several distribution pipes (1-1). The water distribution pipe (1-1) is connected to the ABR reactor, which is used for multi-compartment staged anaerobic treatment; The ABR reactor is connected to the biogas tank via the ABR biogas exhaust pipe (14) to recover biogas; The outlet end of the ABR reactor is connected to the ABR sedimentation tank (4) for separating sludge and clear liquid in wastewater; The lower part of the ABR sedimentation tank (4) is connected to the ABR sludge discharge well (6) through the ABR sedimentation tank sludge collection hopper discharge pipe (4-6) for collecting sludge; the ABR sludge discharge well (6) uses a sludge pump (6-1) to discharge sludge into the anaerobic sludge tank through the ABR sludge pump discharge pipe (20) via the ABR residual sludge discharge pipe (22) and the sludge discharge main pipe. The upper part of the ABR sedimentation tank (4) is connected to the anaerobic intermediate tank (5) for collecting the clear liquid; the clear liquid is connected to the UASB reactor (7) through the UASB inlet pipe (12) for further anaerobic treatment. The sludge produced by the UASB reactor (7) is discharged to the anaerobic sludge tank through the sludge discharge main pipe for sludge treatment; the clear liquid obtained after treatment is discharged into the subsequent treatment device through the main water outlet pipe (11); the biogas obtained after treatment by the UASB reactor (7) is connected to the biogas tank through the UASB biogas exhaust pipe (15) to recover the biogas.

2. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The ABR reactor includes an ABR end guide chamber (2) and at least three ABR compartments. The ABR end guide chamber (2) has a narrow cavity inside, which is used to receive wastewater entering from the water distribution pipe (1-1) and guide the wastewater to its bottom. Wastewater is sequentially introduced into at least three ABR compartments through the ABR end guide chamber (2) for multi-compartment graded anaerobic treatment, and then introduced into the ABR sedimentation tank (4) for separation of clear liquid and sludge.

3. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 2, characterized in that, The three ABR compartments are the first ABR compartment (3-1), the second ABR compartment (3-2), and the third ABR compartment (3-3); the water distribution pipe (1-1) is connected to the ABR end guide chamber (2), through which wastewater is introduced into the inlet end of the first ABR compartment (3-1); the outlet end of the third ABR compartment (3-3) is connected to the ABR sedimentation tank (4); The first ABR compartment (3-1), the second ABR compartment (3-2), and the third ABR compartment (3-3) have the same structure and are arranged in series. Each ABR compartment is separated by a partition wall, and the partition wall has a gap with the bottom of the inner pool of each ABR compartment. Each ABR compartment is vertically equipped with a baffle plate. The space between the baffle plate and the partition wall on the inlet side is defined as the anaerobic reaction chamber. The space between the baffle plate and the partition wall on the outlet side is defined as the internal flow guiding chamber. A gap is left between the top of the baffle plate and the top of the inner tank of the ABR compartment to allow the effluent after passing through the anaerobic reaction chamber to enter the internal flow guiding chamber through the gap at the top of the baffle plate. The anaerobic reaction chamber is equipped with an ABR packing bed. The upper and lower parts of the ABR packing are a connecting zone and an anaerobic reaction zone, respectively. The anaerobic reaction zone will introduce liquid from the ABR end guide chamber (2) or the upstream adjacent ABR compartment into the anaerobic reaction zone for anaerobic reaction. The biogas generated by the mixed liquid after reaction will enter the ABR packing bed for three-phase separation. The connecting zone is used to introduce the anaerobic liquid into the internal guide chamber and introduce it into the downstream adjacent ABR compartment through the gap between the partition wall corresponding to the internal guide chamber and the bottom of the inner pool. The bottom of the anaerobic reaction zone is a sludge accumulation zone, and the sludge accumulated in the sludge accumulation zone is discharged into the anaerobic sludge tank through the ABR excess sludge discharge pipe (22).

4. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The ABR sedimentation tank (4) includes a sedimentation inclined tube (4-2). The lower part of the sedimentation inclined tube (4-2) is supported by an inclined tube bracket (4-1). The upper part of the sedimentation inclined tube (4-2) is provided with a clear water channel (4-3) for collecting the sedimentation clear liquid. The clear water channel (4-3) is connected to the anaerobic intermediate tank (5) through a first water passage (4-4) for discharging the sedimentation clear liquid collected in the clear water channel (4-3) into the anaerobic intermediate tank (5). The bottom of the ABR sedimentation tank (4) is provided with a sludge collection hopper (4-5), and the lower part of the sludge collection hopper (4-5) is provided with an ABR sedimentation tank sludge collection hopper discharge pipe (4-6) for discharging the sludge accumulated in the sludge collection hopper (4-5) into the ABR discharge well (6).

5. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The anaerobic intermediate tank (5) is equipped with a lift pump (5-1) to pump the clear liquid from the ABR sedimentation tank into the UASB reactor (7) through the UASB inlet pipe (12) for further treatment. At the same time, a portion of the clear liquid is pumped into the water distribution tank (1) through the ABR internal return pipe (13) for internal return.

6. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The ABR sludge discharge well (6) is equipped with a sludge pump (6-1), which is connected to the ABR sludge pump discharge pipe (20) to discharge sludge into the water inlet distribution tank (1) through the sludge return pipe (21) and discharge the remaining sludge into the anaerobic sludge tank for sludge treatment through the ABR remaining sludge discharge pipe (22).

7. An integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to any one of claims 1 or 6, characterized in that, The ABR sludge discharge well (6) is equipped with an agitating air pipe (19) for introducing high-pressure air to agitate the sludge in the sludge discharge well.

8. The integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The UASB inlet pipe (12) is connected to several UASB inlet branch pipes (12-1). The clear liquid in the anaerobic intermediate tank (5) enters the UASB reaction tank (7) through the UASB inlet pipe (12) and several UASB inlet branch pipes (12-1). The UASB reaction tank (7) is provided with two reaction tank baffles, and the top of the reaction tank baffles is connected to the top of the tank, and the bottom of the reaction tank baffles is left with a gap for communication with the bottom of the UASB reaction tank (7). The space between the two reaction pool retaining walls and the top of the pool forms a UASB gas storage chamber (8), and the space below the UASB gas storage chamber (8) is connected to the UASB reaction pool (7); the top of the UASB gas storage chamber (8) is provided with a biogas exhaust port for connecting a UASB biogas exhaust pipe (15), and the UASB biogas exhaust pipe (15) is connected to a biogas tank to recover biogas; Three-phase separation zones (7-2) are evenly arranged in the space between the outer side of each reaction pool baffle and the pool wall of the UASB reaction pool (7). Three-phase separator exhaust pipes (7-3) are respectively opened on the reaction pool baffles on both sides of the UASB gas storage chamber (8). The three-phase separator exhaust pipes (7-3) are used to introduce the biogas collected in the three-phase separation zone (7-2) into the UASB gas storage chamber (8) through the three-phase separator exhaust pipes (7-3). Below the three-phase separation zone (7-2) is the anaerobic reaction zone of the UASB reactor (7). The bottom of the UASB reactor (7) is a sludge accumulation zone. Several UASB reactor (7) sludge hoppers are used. The upper opening of the UASB reactor (7) sludge hopper is equipped with a UASB sludge hopper discharge pipe (7-7), which is used to discharge the sludge accumulated at the bottom of the UASB reactor (7) sludge hopper into the anaerobic sludge tank for sludge treatment through the sludge discharge main pipe. Above the three-phase separation zone (7-2) is a water collection channel (7-1), which is connected to the UASB main water collection channel (9) through a second water passage (7-4) set in the wall of the UASB reaction tank (7) for collecting outflowing water; The UASB reactor (7) has a UASB inlet branch pipe (12-1) installed in the sludge hopper through an inlet pipe fixing bracket (7-5).

9. An integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 8, characterized in that, The bottom of several sludge hoppers of the UASB reactor (7) is connected in series with sludge hopper connecting pipes (7-6). The sludge hopper connecting pipes (7-6) are used to connect different sludge hoppers of the UASB reactor (7) and to distribute the sludge in the sludge hoppers of the UASB reactor (7) equally.

10. An integrated multi-stage anaerobic treatment device for treating high-concentration, recalcitrant organic wastewater according to claim 1, characterized in that, The biogas tank includes an ABR biogas storage tank (16-1) and a UASB biogas storage tank (16-2). The ABR biogas storage tank (16-1) and the UASB biogas storage tank (16-2) are located on the top of the ABR reaction tank and are used to connect the ABR biogas exhaust pipe (14) and the UASB biogas exhaust pipe (15), respectively. The tops of the ABR biogas storage tank (16-1) and the UASB biogas storage tank (16-2) are connected by a biogas storage tank connecting pipe (17), which is connected to a biogas discharge main pipe (18). The biogas is discharged to the biogas utilization equipment for thermal energy utilization through the biogas discharge main pipe (18).

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