Sewage treatment system

Abstract

The present application discloses a kind of sewage treatment systems, it is related to the technical field of sewage treatment system, the present application aims at solving the problem that the sand washing process greatly increases hydraulic load, the present application includes physical treatment unit, biological treatment unit, chemical treatment unit and sludge treatment unit, the sludge treatment unit includes sand washing mechanism, centrifugal thickener and heating dewatering machine, the heating dewatering machine includes steam outlet, the steam outlet is communicated with compressor, the output of the compressor is communicated with the sand washing mechanism;The sand washing mechanism includes first sand washer and second sand washer, the compressor is communicated with the input of the first sand washer, the solid outlet of the first sand washer is communicated with the input of the second sand washer, the liquid outlet of the first sand washer is communicated condenser, the output of the condenser is also communicated with the input of the second sand washer;The liquid outlet of the second sand washer is communicated to the biological treatment unit.

Description

Technical Field

[0001] This invention relates to the technical field of urban wastewater treatment, and more specifically to wastewater treatment systems. Background Technology

[0002] Urban wastewater treatment systems are an indispensable public infrastructure in modern cities. Their core task is to efficiently and stably remove pollutants from wastewater, protect the water environment, ensure public health and safety, and develop towards resource recycling and energy self-sufficiency.

[0003] Existing wastewater treatment systems are mainly divided into three basic stages. The first stage uses physical methods, such as filtration and sedimentation, to remove large and coarse particles from the wastewater. The second stage uses biological methods, such as microorganisms, to decompose a large amount of organic matter in the wastewater. The third stage uses chemical methods, such as adding chemicals to coagulate and settle, to remove impurities dissolved in the water.

[0004] In the first stage of treatment, a large amount of inorganic solids such as sand and gravel are typically filtered out. Because these filtered inorganic solids have not undergone biodegradation and chemical precipitation, their surfaces are covered with a large amount of organic matter (such as grease, food residue, and fecal fibers). If this "dirty sand" is transported off-site for disposal or landfill, it will smell bad, breed mosquitoes and flies, pollute the environment, and its organic components will decompose, producing leachate. To avoid this, existing technologies add sand washing tanks to wastewater treatment systems. Sand washing equipment (usually cyclone sand washers or spiral sand washers) uses water flow shearing, friction, and separation to complete the sand washing process. However, the sand washing process requires a large amount of clean water, and the washed water still needs to be transported back to the system for further treatment, greatly increasing the hydraulic load. Summary of the Invention

[0005] To address the aforementioned problem—namely, the significant increase in hydraulic load during sand washing—this invention proposes a wastewater treatment system comprising a physical treatment unit, a biological treatment unit, a chemical treatment unit, and a sludge treatment unit. The physical treatment unit filters larger particulate impurities; the biological treatment unit degrades organic matter; the chemical treatment unit treats impurities dissolved in the water; and the sludge treatment unit treats separated solid impurities. The sludge treatment unit includes a sand washing mechanism, a centrifugal thickener, and a heating dewatering machine. The heating dewatering machine includes a steam outlet connected to a compressor, the compressor's output connected to the sand washing mechanism. The sand washing mechanism includes a first sand washing machine and a second sand washing machine. The compressor is connected to the input port of the first sand washing machine, the solid outlet of the first sand washing machine is connected to the input port of the second sand washing machine, and the liquid outlet of the first sand washing machine is connected to a condenser, the condenser's output also connected to the input port of the second sand washing machine. The liquid outlet of the second sand washing machine is connected to the biological treatment unit.

[0006] A further configuration of the present invention is as follows: the biological treatment unit includes a biological treatment device, which includes a pretreatment tank, an anaerobic tank, and an aeration tank in sequence from the input end to the output end; the liquid outlets of the physical treatment unit and the second sand washing machine are both connected to the pretreatment tank; the anaerobic tank is sealed, and the bottom of the aeration tank is equipped with several air inlets for supplementing air into the aeration tank.

[0007] A further configuration of the present invention is as follows: the biological treatment device further includes a biological sedimentation tank, the aeration tank is connected to the biological sedimentation tank, the solid outlet of the biological sedimentation tank is connected to the pretreatment tank, and the liquid outlet of the biological sedimentation tank is connected to the chemical treatment unit.

[0008] A further provision of the present invention is that the chemical treatment unit includes a biochemical tank for carrying out chemical reactions, the input end of the biochemical tank is connected to the biological treatment unit, and the output end of the biochemical tank is connected to a filtration and disinfection tank.

[0009] A further provision of the present invention is as follows: a detection device is installed inside the biochemical pool. The detection device includes a user terminal, a controller, a spotlight, and a receiver. The spotlight emits light towards the receiver, and the receiver receives the light emitted by the spotlight and generates an electrical signal. The receiver includes a housing, and an mounting plate and a light-transmitting plate are disposed inside the housing. A sealed cavity is provided between the mounting plate and the light-transmitting plate. A plurality of photoresistors are mounted on the mounting plate. The photoresistors are located in the cavity and are connected to the controller via signal lines and a data acquisition card. The controller receives the electrical signal, converts it into a relay signal, and transmits it to the user terminal. The user terminal parses the relay signal and generates resistance data for each photoresistor.

[0010] A further provision of the present invention is that the user terminal generates a grayscale image based on the resistance value of each of the photoresistors.

[0011] A further configuration of the present invention is as follows: three spotlights and three receivers are arranged from top to bottom, with each spotlight corresponding to one receiver; the invention also includes a support frame, which includes a first vertical rod and a second vertical rod; the first vertical rod is connected to three mounting seats, and the three mounting seats are fixedly connected to the three spotlights; the second vertical rod is connected to three clamps, and the three clamps hold the three receivers.

[0012] A further configuration of the present invention is as follows: the physical treatment unit includes a bar screen; a power pump is disposed downstream of the bar screen, the output end of the power pump is connected to a physical sedimentation tank, the solid outlet of the physical sedimentation tank is connected to the input port of the first sand washing machine, and the liquid outlet of the physical sedimentation tank is connected to the biological treatment unit.

[0013] The beneficial effects of this invention are as follows:

[0014] 1. When dewatering sludge, the heating dewatering machine generates a large amount of steam. This steam, after being compressed by the compressor, becomes high-pressure steam. This high-pressure steam is then introduced into the first sand washing machine to wash large particles of impurities. The high-temperature, high-pressure steam rapidly heats the sand particles and organic matter (such as grease) adhering to their surfaces, reducing the stickiness of the organic matter and making it easier to peel off from the sand particles. Simultaneously, when the high-temperature, high-pressure steam comes into contact with the cooler sand particles, it rapidly condenses and shrinks in volume, generating a strong local vacuum and micro-jets, potentially producing a stronger "tearing" peeling effect.

[0015] 2. Using steam evaporated from the sludge for sand washing avoids the need to use clean water, further saving water consumption in the sand washing process and not significantly increasing the hydraulic load of subsequent sewage treatment, thus greatly improving the efficiency of sewage treatment.

[0016] 3. This invention utilizes the varying degrees of light obstruction by the flocculent matter within the biochemical tank to reflect the different stages the tank is in, allowing corresponding changes to be detected by a photoresistor, effectively avoiding the limitations of image technology. Ultimately, image technology is still used at the user terminal, generating grayscale images to visualize the data and facilitate intuitive understanding of the data by technical personnel, thus preserving the advantages of image technology. Attached Figure Description

[0017] Figure 1 A schematic diagram of the system structure of the present invention is shown.

[0018] Figure 2 A schematic diagram of the biological treatment unit is shown.

[0019] Figure 3 A schematic diagram of the sand washing mechanism is shown.

[0020] Figure 4 A system schematic diagram of the detection device is shown.

[0021] Figure 5 A schematic diagram of the detection device is shown. Figure 1 .

[0022] Figure 6 A schematic diagram of the detection device is shown. Figure 2 .

[0023] Figure 7 A partial cross-sectional view of the receiver is shown.

[0024] Reference numerals: 1. Physical treatment unit; 11. Bar screen; 12. Power pump; 13. Physical sedimentation tank; 2. Biological treatment unit; 21. Biological treatment device; 211. Pretreatment tank; 212. Anaerobic tank; 213. Aeration tank; 22. Biological sedimentation tank; 3. Chemical treatment unit; 31. Biochemical tank; 32. Filtration and disinfection tank; 4. Sludge treatment unit; 41. Centrifugal thickener; 42. Heating dewatering machine; 43. Compressor; 44. Sand washing mechanism; 441. First sand washing machine; 442. Second sand washing machine; 443. Condenser; 5. User terminal; 6. Controller; 7. Receiver; 71. Housing; 72. Mounting plate; 73. Light-transmitting plate; 74. Photoresistor; 8. Spotlight; 9. Support frame; 91. First vertical rod; 92. Mounting base; 93. Second vertical rod; 94. Clamp; 95. Horizontal bar. Detailed Implementation

[0025] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0026] refer to Figures 1-3 This invention proposes a wastewater treatment system, comprising a physical treatment unit 1, a biological treatment unit 2, a chemical treatment unit 3, and a sludge treatment unit 4. The physical treatment unit 1 filters out larger particulate impurities, and wastewater first enters the physical treatment unit 1 for treatment. The biological treatment unit 2 degrades organic matter in the wastewater using microorganisms. The chemical treatment unit 3 treats dissolved impurities in the water, i.e., substances not treated by the physical treatment unit 1 and the biological treatment unit 2. The sludge treatment unit 4 treats the impurities and sludge produced by the physical treatment unit 1 and the biological treatment unit 2.

[0027] The sludge treatment unit 4 includes a sand washing mechanism 44, a centrifugal thickener 41, and a heating dewatering machine 42. The heating dewatering machine 42 includes a steam outlet, and a compressor 43 is connected to the steam outlet. The compressor 43 can pressurize the steam output from the heating dewatering machine 42 into high-pressure and high-temperature steam. The output end of the compressor 43 is connected to the sand washing mechanism 44 to input the high-temperature and high-pressure steam into the sand washing mechanism 44.

[0028] The sand washing mechanism 44 includes a first sand washing machine 441 and a second sand washing machine 442. Both the first sand washing machine 441 and the second sand washing machine 442 are cyclone sand washing machines. The inlet of the first sand washing machine 441 is connected to the compressor 43. At the same time, the solid outlet of the physical processing unit 1 is also connected to the inlet of the first sand washing machine 441. High-temperature and high-pressure steam will swirl and collide with large particles of impurities in the first sand washing machine 441. During the collision process, the impurities and the organic matter attached to their surfaces will also heat up, while the steam temperature will drop and condense, thereby reducing the viscosity of the organic matter and making it easier to peel off from the impurities.

[0029] The solid outlet of the first sand washing machine 441 is connected to the inlet of the second sand washing machine 442 to allow impurities washed by steam to enter the second sand washing machine 442. The liquid outlet of the first sand washing machine 441 is connected to a condenser 443, which allows uncondensed steam to continue to condense. The outlet of the condenser 443 is also connected to the inlet of the second sand washing machine 442, and the condensate is continuously injected into the second sand washing machine 442. The condensate and impurities in the second sand washing machine 442 undergo a secondary sand washing process to ensure thorough sand washing. The liquid outlet of the second sand washing machine 442 is connected to the biological treatment unit 2. After the sand washing process is completed, the condensate in the second sand washing machine 442 is transported to the biological treatment unit 2 for biodegradation, and then enters the chemical treatment unit 3 for chemical treatment.

[0030] The physical treatment unit 1 includes a screen 11, which can treat and filter sewage. A power pump 12 is installed downstream of the screen 11. The output end of the power pump 12 is connected to a physical sedimentation tank 13. That is, the sewage filtered by the screen 11 will be pumped into the physical sedimentation tank 13 by the power pump 12 and undergo static sedimentation in the physical sedimentation tank 13. The solid outlet of the physical sedimentation tank 13 is connected to the input port of the first sand washing machine 441, and the liquid outlet of the physical sedimentation tank 13 is connected to the biological treatment unit 2.

[0031] The biological treatment unit 2 includes a biological treatment device 21. The inlet of the biological treatment device 21 is connected to the physical sedimentation tank 13. The biological treatment device 21 includes a pretreatment tank 211, an anaerobic tank 212, and an aeration tank 213 in sequence from the inlet to the outlet. The anaerobic tank 212 is sealed during use. The pretreatment tank 211, the anaerobic tank 212, and the aeration tank 213 are connected in sequence and connected in the middle by a valve. When the anaerobic tank 212 is working, the valve is closed to keep the anaerobic tank 212 sealed.

[0032] The liquid outlets of both the physical treatment unit 1 and the second sand washing machine 442 are connected to the pretreatment tank 211. Several air supply ports are installed at the bottom of the aeration tank 213, and air supply ports are connected to air pumps, which can supply air to the bottom of the aeration tank 213.

[0033] It should be noted that when the wastewater being treated only requires degradation by anaerobic microorganisms, the air supply port is inactive and closed, and the aeration tank 213 is used only as a connecting chamber. When the wastewater being treated only requires degradation by aerobic microorganisms, the valve of the anaerobic tank 212 is always open, and the anaerobic tank 212 is used only as a connecting chamber. When the wastewater requires degradation by both types of microorganisms, the wastewater will first undergo anaerobic degradation in the sealed state of the anaerobic tank 212, and after degradation is completed, it will be sent to the aeration tank 213 for aerobic degradation.

[0034] The biological treatment device 21 also includes a biological sedimentation tank 22, and an aeration tank 213 is connected to the biological sedimentation tank 22. When wastewater flows from the biological treatment device 21 into the biological sedimentation tank 22, it carries some microorganisms with it. The solids outlet of the biological sedimentation tank 22 is connected to the inlet of the pretreatment tank 211, so that the carried-out microorganisms can be transported back to the pretreatment tank 211. Only a portion of the returned microorganisms are active. These partially active microorganisms will perform preliminary degradation of the wastewater in the pretreatment tank 211, which avoids the waste of microorganisms and improves degradation efficiency. Once the degradation is complete, the microorganisms in the pretreatment tank 211 can be completely removed and no longer used.

[0035] The chemical treatment unit 3 includes a biological treatment tank 31 for chemical reactions. The input end of the biological treatment tank 31 is connected to the biological sedimentation tank 22 of the biological treatment unit 2. Wastewater treated by the biological treatment unit 2 is transported into the biological treatment tank 31 for chemical reactions to remove harmful substances dissolved in the water. The output end of the biological treatment tank 31 is connected to a filtration and disinfection tank 32. The filtration and disinfection tank is used for final disinfection and filtration of the treated water, which is then discharged from the filtration and disinfection tank 32 or used as recycled water.

[0036] It should be noted that the sludge treated by the heating and dewatering machine 42 will be discharged for landfill, agricultural use, incineration or composting.

[0037] refer to Figures 3-7 The biochemical tank 31 is also equipped with a detection device, which is fixed inside the tank. The detection device includes a user terminal 5, a controller 6, three sets of spotlights 8, and three sets of receivers 7. The user terminal 5 can be a computer, mobile phone, or tablet. The controller 6 uses an industrial PLC. When the user terminal 5 is a computer, it can be connected to the controller 6 via a line. When the user terminal 5 is a mobile device (mobile phone or tablet), it can also be connected by adding a DTU module or setting a wireless gateway.

[0038] The three sets of spotlights 8 and the three sets of receivers 7 are arranged from top to bottom and correspond one-to-one. The spotlights 8 emit light horizontally towards the receivers 7, and the receivers 7 are used to receive the light emitted by the spotlights 8 and generate electrical signals.

[0039] In addition, a support frame 9 is included to secure the spotlights 8 and receivers 7. The support frame 9 includes a first vertical rod 91 and a second vertical rod 93. The first vertical rod 91 connects to three mounting bases 92, which are fixedly connected to the three spotlights 8. The second vertical rod 93 connects to three clamps 94, which hold the three receivers 7. In an optional embodiment, the support frame 9 may also include a horizontal rod 95. The horizontal rod 95 connects the tops of the first vertical rod 91 and the second vertical rod 93 and is fixedly connected within the biochemical tank 31. The horizontal rod 95 can fix the positions of the first vertical rod 91 and the second vertical rod 93, but since the first vertical rod 91 and the second vertical rod 93 can be adjusted to different spacings according to usage needs, and different users can even choose a suitable fixing method for the first vertical rod 91 and the second vertical rod 93, the horizontal rod 95 is not necessary. If the horizontal rod 95 is not used, the first vertical rod 91 and the second vertical rod 93 are directly fixedly connected to the biochemical tank 31.

[0040] The receiver 7 includes a cylindrical housing 71. Inside the housing 71, a mounting plate 72 and a light-transmitting plate 73 are disposed, with a sealed cavity between the mounting plate 72 and the light-transmitting plate 73. Several photoresistors 74 are mounted on the mounting plate 72. Preferably, the photoresistors 74 are distributed in a 30×30 square matrix on the mounting plate 72. The photoresistors 74 are located within the cavity and are connected to the controller 6 via signal lines and a data acquisition card. The light-transmitting plate 73 is a transparent material. Light emitted from the spotlight 8 passes through the light-transmitting plate 73 and illuminates the photoresistors 74. The photoresistors 74 then generate signals of varying intensities based on the light intensity.

[0041] The controller 6 processes the electrical signal of the photoresistor 74 and generates a relay signal. The relay signal is sent to the user terminal 5. The user terminal 5 parses the relay signal and generates the resistance data of each photoresistor 74. It also generates a grayscale image based on the resistance data.

[0042] The photoresistor 74 used is model GL5528. Its light resistance is approximately 10KΩ, and its dark resistance is approximately 1MΩ. Different resistance values ​​are matched with different grayscale values: 10KΩ corresponds to a grayscale value of 255, and 1MΩ corresponds to a grayscale value of 0. Grayscale values ​​between 0 and 255 are matched using an arithmetic progression from 10KΩ to 1MΩ. In other words, the photoresistor 74 will exhibit different resistance changes when exposed to light of varying intensities. By matching the resistance changes with corresponding grayscale values, a 30×30 grayscale matrix can be generated. This grayscale matrix can then be visualized by constructing a 30×30 area, with each coordinate point positioned within a square, and the squares filled with the color corresponding to the grayscale value of that coordinate point. Data from the photoresistor 74 can be collected at specific intervals.

[0043] The changes in the resistance of the photoresistor 74 are explained in detail here.

[0044] 1. Rapid Adsorption Phase. This phase begins with the start of operation of biological treatment tank 31. Microorganisms rapidly adsorb colloidal and dissolved organic matter in the wastewater, with the adsorption rate far exceeding the degradation rate. Microbial activity is not yet fully activated. The organic matter concentration in biological treatment tank 31 is high, and a large number of organic particles adhere to the surface of the flocs; there are no obvious floc-bubble complexes.

[0045] Data characteristics of photoresistor 74: The resistance value of photoresistor 74 is 60%-70% of the voltage divider resistor value (the voltage divider resistor is a necessary and fixed resistor in the photoresistor 74 circuit, which belongs to the existing technology), with good uniformity, scattered high resistance points accounting for ≤3%, and no large areas of high resistance.

[0046] 2. Initial stage of degradation. Adsorbed organic matter begins to be degraded by microorganisms, increasing the intracellular metabolic rate; oxygen demand gradually increases, and microbial activity rises rapidly. The flocs expand slightly due to metabolic activity, increasing the probability of contact between bubbles and flocs, and a small number of small-area floc-bubble complexes are formed.

[0047] The data characteristics of the photoresistor 74 are as follows: scattered high-resistance points account for 5%-7%, with localized high-resistance regions of at least 2×2. The resistance value within the high-resistance region is between 100% and 110% of the voltage divider resistance value.

[0048] 3. High-efficiency degradation phase. Microorganisms enter the logarithmic growth phase, and the degradation rate of organic matter reaches its peak; intracellular respiration is vigorous, and oxygen demand remains high; degradation products are continuously released, the turbidity of the mixed liquor decreases, and the floc structure becomes dense; a large number of tiny bubbles generated by degradation adhere to the surface of the flocs, forming a dense floc-bubble complex.

[0049] The 74-inch photoresistor exhibits the following characteristics: localized high-resistance regions of at least 3×3 or 4×4. Within these high-resistance regions, the resistance is between 120% and 140% of the voltage divider resistance.

[0050] 4. Degradation and Decline Phase. Most organic matter has been degraded, leaving only a small amount of recalcitrant substances; microbial activity decreases, and oxygen demand gradually decreases; some microorganisms enter the endogenous respiration stage. The clarity of the mixed liquor is significantly improved, and the flocs shrink and become denser due to endogenous respiration; the floc-bubble complex disintegrates, and the bubbles redisperse into small-diameter independent bubbles.

[0051] The characteristics of the 74 photoresistor are as follows: the overall resistance is between 80% and 90% of the voltage divider resistance value, the large areas of high resistance disappear, and the proportion of scattered high resistance points drops to about 5%.

[0052] 5. Endogenous respiration phase. Organic matter is depleted, and microorganisms metabolize using their own cytoplasm as a nutrient source; activity further decreases, and oxygen demand drops to its lowest point; sludge settling performance is enhanced. Mixed liquor transparency increases, floc particle size is uniform; bubbles are evenly distributed, with no floc adhesion; some flocs begin to settle.

[0053] Photoresistor 74 data characteristics: the overall resistance value is between 60% and 70% of the voltage divider resistance value, and the proportion of scattered high resistance points is ≤3%.

[0054] Based on this, judgments can be made on a series of specific situations.

[0055] If the overall resistance is below 50% of the partial voltage resistance, the bio-sludge cultivation is insufficient. If the area of ​​the high-resistance region exceeds 5×5 and shows a continuous expanding trend, and the resistance within the high-resistance region is below 100% of the partial voltage resistance, or shows a continuous decreasing trend, it usually indicates that abnormal proliferation of filamentous bacteria has led to loose flocs.

[0056] If the data from all three receivers 73 meet the characteristics of the "endogenous respiration period" mentioned above, then the biochemical treatment can be considered complete.

[0057] Finally, grayscale images can be generated based on the resistance values ​​of different photoresistors 74. At the user terminal 5, technicians can directly view the grayscale images to determine the situation in the biochemical tank 31. With the application of intelligent technology, neural network algorithms can also be used to learn from a large number of grayscale images, thereby providing judgment conclusions for different grayscale images using an algorithmic model.

[0058] Traditionally, technicians need to periodically inspect the condition of the biological treatment tank 31 on-site. Visual observation relies heavily on experience and is affected to some extent by external factors like snow and rain. Furthermore, continuous sampling and testing are required. While this technology cannot completely eliminate sampling and testing—in fact, no image technology or artificial intelligence technology can completely eliminate this—the solution of this invention can reduce the frequency of testing. When the treatment process in the biological treatment tank 31 meets expectations, i.e., the final grayscale image meets expectations, the frequency of testing can be reduced, and on-site observation by technicians is unnecessary. More importantly, compared to current image recognition technologies that photograph the biological treatment tank 31, this invention is completely unaffected by environmental factors such as sunlight, water reflections, and surface foam. Simply put, this invention utilizes the different levels of light obstruction by the flocculent matter within the biological treatment tank 31 to reflect different stages of the tank's development, allowing corresponding changes to be detected by the photoresistor 74, effectively avoiding the limitations of image technology. Ultimately, image technology, namely generating grayscale images, is still used on user terminal 5 to visualize the data, making it easier for technicians to intuitively understand the data situation, thus retaining the advantages of image technology.

[0059] Furthermore, the above process can be summarized into a method. This method includes the following: A spotlight and a receiver 7 are installed in the biochemical tank 31. The receiver 7 includes several photoresistors 74, preferably arranged in a 30×30 matrix, and the photoresistors 74 should be placed in a sealed cavity to ensure insulation. The photoresistors 74 transmit electrical signals to the controller 6 (PLC) via signal lines and a data acquisition card. After processing by the controller 6, a relay signal is generated and sent to the user terminal 5. The relay signal is parsed to generate resistance data for each photoresistor 74, and a grayscale image is also generated based on the resistance data. The photoresistors 74 sample at a specific period, such as 5 seconds / sample. The technician then judges the situation within the biochemical tank 31 based on the changes in the grayscale image, or the judgment can be made using an algorithm model to learn the grayscale image.

[0060] In summary, this invention generates a large amount of steam during the dewatering of sludge using the heating dewatering machine 42. This steam, after being compressed by the compressor 43, becomes high-pressure steam. Introducing this high-pressure steam into the first sand washing machine 441 enables the washing of large particles of impurities. The high-temperature, high-pressure steam rapidly heats the sand particles and organic matter (such as grease) adhering to their surfaces, reducing the stickiness of the organic matter and making it easier to peel off from the sand particles. Simultaneously, when the high-temperature, high-pressure steam comes into contact with the cooler sand particles, it rapidly condenses and shrinks in volume, generating a strong local vacuum and microjets, potentially producing a stronger "tearing" peeling effect.

[0061] Using steam evaporated from sludge for sand washing avoids the need for clean water, further saving water consumption during the sand washing process and significantly increasing the hydraulic load on subsequent wastewater treatment, thus greatly improving wastewater treatment efficiency.

[0062] This invention utilizes the varying degrees of light obstruction by the flocculent matter within the biochemical tank 31 to reflect the different stages the tank is in, allowing corresponding changes to be detected by the photoresistor 74, effectively avoiding the limitations of image technology. Ultimately, image technology, specifically generating a grayscale image, is still used on the user terminal 5 to visualize the data, facilitating a more intuitive understanding of the data by technical personnel, thus preserving the advantages of image technology.

[0063] Although the invention has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0064] In the description of this invention, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," which indicate direction or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0065] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0066] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to those processes, articles, or apparatus / devices.

[0067] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A wastewater treatment system comprising a physical treatment unit (1), a biological treatment unit (2), a chemical treatment unit (3), and a sludge treatment unit (4), wherein the physical treatment unit (1) is used to filter larger particulate impurities, the biological treatment unit (2) is used to degrade organic matter, the chemical treatment unit (3) is used to treat impurities dissolved in water, and the sludge treatment unit (4) is used to treat separated solid impurities, wherein the sludge treatment unit (4) includes a sand washing mechanism (44), a centrifugal thickener (41), and a heating dewatering machine (42), characterized in that: The heating dehydrator (42) includes a steam outlet, and a compressor (43) is connected to the steam outlet. The output end of the compressor (43) is connected to the sand washing mechanism (44). The sand washing mechanism (44) includes a first sand washing machine (441) and a second sand washing machine (442). The compressor (43) is connected to the input port of the first sand washing machine (441). The solid outlet of the first sand washing machine (441) is connected to the input port of the second sand washing machine (442). The liquid outlet of the first sand washing machine (441) is connected to a condenser (443). The output end of the condenser (443) is also connected to the input port of the second sand washing machine (442). The liquid outlet of the second sand washing machine (442) is connected to the biological treatment unit (2).

2. The wastewater treatment system according to claim 1, characterized in that: The biological treatment unit (2) includes a biological treatment device (21), which includes a pretreatment tank (211), an anaerobic tank (212), and an aeration tank (213) from the input end to the output end. The liquid outlets of the physical treatment unit (1) and the second sand washing machine (442) are connected to the pretreatment tank (211). The anaerobic tank (212) is sealed, and the bottom of the aeration tank (213) is equipped with several air inlets for supplementing air into the aeration tank (213).

3. The wastewater treatment system according to claim 2, characterized in that: The biological treatment device (21) further includes a biological sedimentation tank (22), the aeration tank (213) is connected to the biological sedimentation tank (22), the solid outlet of the biological sedimentation tank (22) is connected to the pretreatment tank (211), and the liquid outlet of the biological sedimentation tank (22) is connected to the chemical treatment unit (3).

4. The wastewater treatment system according to claim 1, characterized in that: The chemical treatment unit (3) includes a biochemical tank (31) for carrying out chemical reactions. The input end of the biochemical tank (31) is connected to the biological treatment unit (2), and the output end of the biochemical tank (31) is connected to a filtration and disinfection tank (32).

5. The wastewater treatment system according to claim 4, characterized in that: The biochemical pool (31) is equipped with a detection device, which includes a user terminal (5), a controller (6), a spotlight (8), and a receiver (7). The spotlight (8) is used to emit light to the receiver (7), and the receiver (7) is used to receive the light emitted by the spotlight (8) and generate an electrical signal. The receiver (7) includes a shell (71), and an installation plate (72) and a light-transmitting plate (73) are provided inside the shell (71). A sealed cavity is provided between the installation plate (72) and the light-transmitting plate (73). Several photoresistors (74) are installed on the installation plate (72). The photoresistors (74) are located in the cavity and are connected to the controller (6) through signal lines and a data acquisition card. The controller (6) is used to receive the electrical signal, convert it into a relay signal, and transmit it to the user terminal (5). The user terminal (5) is used to parse the relay signal and generate resistance data of each photoresistor (74).

6. The wastewater treatment system according to claim 5, characterized in that: The user terminal (5) generates a grayscale image based on the resistance values ​​of each photoresistor (74).

7. The wastewater treatment system according to claim 5, characterized in that: The spotlights (8) and receivers (7) are arranged in three positions from top to bottom, with each spotlight (8) corresponding to a receiver (7). The system also includes a support frame (9), which includes a first vertical rod (91) and a second vertical rod (93). The first vertical rod (91) is connected to three mounting bases (92), and the three mounting bases (92) are fixedly connected to the three spotlights (8). The second vertical rod (93) is connected to three clamps (94), and the three clamps (94) hold the three receivers (7).

8. The wastewater treatment system according to claim 1, characterized in that: The physical treatment unit (1) includes a screen (11); a power pump (12) is provided downstream of the screen (11), the output end of the power pump (12) is connected to a physical sedimentation tank (13), the solid outlet of the physical sedimentation tank (13) is connected to the input port of the first sand washing machine (441), and the liquid outlet of the physical sedimentation tank (13) is connected to the biological treatment unit (2).

Images