A device and method for resource utilization of salt-containing organic waste liquid

Abstract

The application discloses a device and method for resource utilization of salt-containing organic waste liquid, the device comprising an evaporation crystallizer, a salt treatment system, and a wastewater treatment system; wherein the evaporation crystallizer is used for receiving the salt-containing organic waste liquid, evaporating the salt-containing organic waste liquid in an evaporation chamber, and outputting coarse salt crystals and wastewater; the salt treatment system comprises a coarse salt treatment subsystem and a fine salt treatment subsystem, the coarse salt treatment subsystem receives the coarse salt crystals for high-temperature melting treatment to obtain coarse salt crystals, and the fine salt treatment subsystem separates salt and nitre from the coarse salt crystals and obtains sodium chloride salt and sodium sulfate salt; the wastewater treatment system receives the wastewater output by the evaporation crystallizer, biologically treats and oxidizes the wastewater, removes organic matters in the wastewater, and outputs fresh water after filtration by a filtering device. The application realizes efficient separation and recovery of salt, optimizes the treatment process, reduces energy consumption and treatment cost, deeply treats the wastewater, and avoids pollution to the environment.

Description

Technical Field

[0001] This invention relates to the field of saline organic waste liquid treatment technology, and in particular to an apparatus and method for the resource utilization of saline organic waste liquid. Background Technology

[0002] High-salinity organic wastewater is generated in numerous industrial processes, such as chemical, pharmaceutical, leather, and electroplating industries, and in large quantities. This type of wastewater is rich in organic pollutants and high concentrations of salt, with a complex chemical composition and is highly environmentally polluting, containing glycerol, low-to-medium carbon chain compounds, and benzene ring organic compounds. The complex and diverse composition and high salt content strongly inhibit microbial growth, making the treatment technology for this wastewater far more challenging than that for ordinary sewage treatment. The resource utilization of high-salinity wastewater aims to efficiently and cost-effectively remove organic matter and heavy metal ions from the wastewater, while simultaneously achieving the comprehensive recovery and utilization of inorganic salts and water resources.

[0003] Current research and commonly used methods for treating and utilizing saline organic wastewater include traditional methods such as evaporation, electrolysis, membrane separation, incineration, and biological methods. These methods suffer from high treatment costs, resource waste, and the potential for secondary pollution. For example, evaporation methods typically employ MVR (Mechanical Vapor Recompression), but due to the high salt and organic matter content, the equipment is prone to scaling and clogging, leading to operational difficulties. The wastewater generated after evaporation is difficult to treat biologically, and the waste salt is usually landfilled as hazardous waste, which not only wastes resources but also fails to address the root cause of the problem. Direct discharge severely pollutes water bodies and soil. Simple incineration is not only energy-intensive but may also produce harmful gases, and the high-salt wastewater severely corrodes the incinerator.

[0004] Therefore, there is an urgent need to provide a COD removal and resource recovery system for high-salt organic waste liquid. Summary of the Invention

[0005] The purpose of this invention is to provide an apparatus and method for the resource utilization of saline organic waste liquid, so as to at least partially solve the above-mentioned problems of the prior art.

[0006] To achieve the above objectives, the present invention provides an apparatus for the resource utilization of saline organic waste liquid, comprising an evaporator crystallizer 10, a salt treatment system 20, and a wastewater treatment system 30; wherein Evaporator crystallizer 10 is used to receive salt-containing organic waste liquid, evaporate the salt-containing organic waste liquid in the evaporation chamber, and output crude salt crystals and wastewater; The salt treatment system 20 includes a crude salt treatment subsystem 21 and a refined salt treatment subsystem 22. The crude salt treatment subsystem 21 receives crude salt crystals and performs high-temperature melting treatment to obtain crude salt crystals. The refined salt treatment subsystem 22 performs salt-nitrate separation and crystallization separation on the crude salt crystals to obtain sodium chloride salt and sodium sulfate salt. Wastewater treatment system 30 receives wastewater from evaporator crystallizer 10, performs biological and oxidation treatment on the wastewater to remove organic matter, and outputs fresh water and concentrated water after filtration using a filtration device.

[0007] Preferably, the device further includes an oil separator 10 for storing saline organic waste liquid, allowing it to stand to achieve oil-water separation of the saline organic waste liquid, and then transporting the lower layer of saline organic waste liquid to the evaporator crystallizer 20.

[0008] Preferably, the crude salt treatment subsystem 21 includes a high-temperature melting furnace, slag discharge cooling equipment, a secondary combustion chamber, waste heat recovery equipment, and flue gas treatment equipment; The high-temperature melting furnace receives the crude salt crystals output from the evaporator crystallizer 10 and melts them into a liquid state. The lower layer of the high-temperature melting furnace is high-temperature molten glass, on which the crude salt crystals are placed. Above the crude salt crystals is a gas phase space containing an oxidant used to oxidize the organic matter in the crude salt. After the crude salt crystals melt, they flow out into a slag discharge and cooling device, which cools the molten salt to a solid state before outputting it. The secondary combustion chamber receives the flue gas generated by the high-temperature melting furnace and performs complete combustion on the flue gas to decompose organic pollutants in the flue gas; The waste heat recovery equipment receives the flue gas after it has been treated in the secondary combustion chamber. It uses a water circulation device to exchange heat with the flue gas to generate steam. The cooled flue gas then enters the flue gas treatment equipment. Flue gas treatment equipment is used to desulfurize and / or remove ammonia from cooled flue gas before it is discharged.

[0009] Preferably, the waste heat recovery equipment is connected to the evaporator crystallizer 10 to provide steam to the evaporator crystallizer 10.

[0010] Preferably, the refined salt treatment subsystem 22 includes a salt dissolving tank, a reaction sedimentation tank, a filtration device, a freeze crystallization device, and an evaporation device; The salt dissolving tank is used to receive and dissolve the crude salt output from the crude salt treatment subsystem 21. A reaction sedimentation tank is used to deposit insoluble substances in a crude salt solution using precipitants and / or flocculants. The filtration equipment is used to filter the crude salt solution output from the reaction sedimentation tank; The freeze crystallization equipment is used to freeze crystallize the salt solution after filtration by the filtration equipment to precipitate sodium sulfate product; The sodium chloride evaporation system receives the salt solution processed by the freeze crystallization equipment and evaporates and crystallizes it to obtain sodium chloride product.

[0011] Preferably, the device further includes: A decarbonization neutralization tank, connected to a reaction sedimentation tank and filtration equipment, is used to decarbonize wastewater before filtration; and / or The mixed salt evaporation system is connected to the sodium chloride evaporation system and is used to further evaporate the wastewater after it has been treated by the sodium chloride evaporation system, thereby precipitating mixed salts.

[0012] Preferably, the wastewater treatment system 30 includes: Oxidation equipment is used to oxidize organic matter in wastewater; At least one of the following: hydrolysis acidification equipment, anaerobic tank, and two-stage A / O equipment: The hydrolysis acidification equipment is used to hydrolyze and acidify the organic matter in wastewater, with the precipitated sludge discharged into a sludge tank; the anaerobic tank uses anaerobic microorganisms to decompose and transform the organic matter in the wastewater; the two-stage A / O equipment is used to oxidize the organic matter in the wastewater under the action of aerobic microorganisms and remove nitrogenous pollutants from the wastewater through nitrification-denitrification; and The filtration system filters the treated wastewater and outputs freshwater for recycling.

[0013] Preferably, the filtration system includes: MBR membrane tanks separate sludge from water in wastewater, and input the supernatant into the RO system; The RO system filters the wastewater again to obtain fresh water and concentrated water, which are then output separately.

[0014] In another aspect, the present invention provides a method for the resource utilization of saline organic waste liquid, applied to the apparatus provided in the above aspects and any preferred embodiments thereof, comprising: The saline organic waste liquid is subjected to evaporation and crystallization treatment to obtain crude salt crystals and wastewater. The crude salt crystals are subjected to high-temperature melting treatment to obtain crude salt crystals, and the crude salt crystals are subjected to salt-nitrate separation and crystallization separation to obtain sodium chloride salt and sodium sulfate salt; Wastewater is treated biologically and through oxidation to produce fresh water.

[0015] Preferably, before evaporating and crystallizing the saline organic waste liquid, the method further includes: allowing the saline organic waste liquid to stand to achieve oil-water separation, removing the upper layer of oil impurities, and obtaining the saline organic waste liquid.

[0016] Compared with the prior art, the present invention has at least the following advantages: The process involves evaporation and crystallization, high-temperature melting, and salt-nitrate separation and crystallization to obtain sodium chloride and sodium sulfate. The wastewater generated from evaporation and crystallization is then subjected to biological and oxidation treatment to remove organic matter. After filtration, fresh and concentrated water are output, achieving efficient separation and recovery of salts. This optimizes the treatment process, reduces energy consumption and treatment costs, and enables the deep treatment of wastewater to meet standards for reuse, avoiding environmental pollution and demonstrating significant environmental benefits. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a device for the resource utilization of saline organic waste liquid provided in Embodiment 1 of the present invention.

[0018] Figure 2 This is a schematic diagram of an example structure of the evaporator crystallizer of the apparatus provided in Embodiment 1 of the present invention.

[0019] Figure 3 This is a schematic diagram of an example structure of the crude salt treatment subsystem of the device provided in Embodiment 1 of the present invention.

[0020] Figure 4 This is a schematic diagram of an example structure of the fine salt treatment subsystem of the device provided in Embodiment 1 of the present invention.

[0021] Figure 5 This is a schematic diagram of an example structure of the wastewater treatment system provided in Embodiment 1 of the present invention.

[0022] Figure 6 This is a schematic flowchart of a method for resource utilization of saline organic waste liquid provided in Embodiment 2 of the present invention. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate to understand the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a product or device comprising a series of units is not necessarily limited to those explicitly listed, but may include other units not explicitly listed or inherent to such product or device.

[0025] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0026] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0027] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Example 1

[0029] Embodiment 1 of the present invention provides a device for the resource utilization of saline organic waste liquid. Figure 1 A schematic diagram of the device is shown, as follows: Figure 1 As shown, the device includes an evaporator crystallizer 10, a salt treatment system 20, and a wastewater treatment system 30; wherein Evaporator crystallizer 10 is used to receive salt-containing organic waste liquid, evaporate the salt-containing organic waste liquid in the evaporation chamber, and output crude salt crystals and wastewater; The salt treatment system 20 includes a crude salt treatment subsystem 21 and a refined salt treatment subsystem 22. The crude salt treatment subsystem 21 receives crude salt crystals and performs high-temperature melting treatment to obtain crude salt crystals. The refined salt treatment subsystem 22 performs salt-nitrate separation and crystallization separation on the crude salt crystals to obtain sodium chloride salt and sodium sulfate salt. Wastewater treatment system 30 receives wastewater from evaporator crystallizer 10, performs biological and oxidation treatment on the wastewater to remove organic matter, and outputs fresh water and concentrated water after filtration using a filtration device.

[0030] In a preferred embodiment, the device may further include an oil separator 10 for storing saline organic waste liquid, allowing it to settle to achieve oil-water stratification, and then transporting the lower layer of saline organic waste liquid to an evaporator crystallizer 20. Settling removes the upper layer of light oily impurities, reducing the difficulty and cost of subsequent treatment. The oily impurities can also be sent to a coarse salt treatment subsystem 21 to provide heat energy as supplementary fuel for the high-temperature melting system. In one example, the high-salt organic waste liquid can be pumped into a settling tank and left to settle for 24 to 48 hours to allow the oil and water in the waste liquid to naturally separate. Subsequently, the upper layer of light oil is collected in an oil tank through a dedicated pipeline to supply fuel oil for the secondary combustion chamber of the high-temperature melting system; while the lower layer of saline organic waste liquid flows into the next treatment unit for further processing.

[0031] The evaporator crystallizer 10 is used to treat saline waste liquid through evaporation and crystallization. In one embodiment, low-temperature evaporation technology is employed, and energy consumption is reduced by compressing and reusing secondary steam, which promotes the crystallization and precipitation of salt. During this process, a large amount of organic matter is precipitated along with the salt, resulting in crude salt crystals with low water content, and no mother liquor is generated during the evaporation process.

[0032] The preferred evaporator is a low-temperature MVR (Mechanical Vapor Recompression) film evaporator powered by secondary steam recovery from a compressor, controlling the evaporation temperature between 35-90℃ to allow salt and organic matter to precipitate. The vacuum in the evaporation chamber is maintained at 40-85 kPa, with approximately 90% of the water evaporated, and salt and high-boiling-point organic matter precipitated to obtain crude salt crystals. The solid water content of the crude salt crystals is 5%–15%. The precipitated crude salt crystals are then fed into subsequent treatment, while the evaporated wastewater is fed into a regulating tank for further treatment. Alternatively, a low-temperature steam scraped-plate evaporator or a heat pump scraped-plate evaporator can be used.

[0033] Figure 2 A schematic diagram of an example structure of the evaporator crystallizer 10 is shown. (Reference) Figure 2 As shown, the evaporator crystallizer 10 includes an evaporation chamber, a steam compressor, a distillation water tank, and a crystallization waste salt tank. The evaporation chamber includes a hollow disc heat exchanger, a scraper, and a screw conveyor. The vacuum generated by the steam compressor will cool the salt-containing waste liquid (… Figure 2The example in the text describes a process where high-COD, high-salt wastewater is drawn into an evaporation chamber. A water pump can then spray the drawn-in saline wastewater onto the outer surface of a hollow disc heat exchanger. A steam compressor heats the wastewater to its boiling point, outputting high-temperature steam. This high-temperature steam passes through the interior of the hollow disc heat exchanger, exchanging heat with the saline wastewater on its outer surface. The saline wastewater evaporates to produce water vapor, which is then fed into the steam compressor as low-temperature steam. The steam compressor compresses and heats the vapor, then sends it to the hollow disc heat exchanger where it is used as a heat source for heat exchange and condensation. During this continuous steam compression and heat exchange process, crystals gradually accumulate on the surface of the hollow disc heat exchanger. A scraper system cleans these crystals, preventing scaling. The condensate from inside the hollow disc heat exchanger is transported to an evaporation tank, while the crystals scraped off by the scraper enter a screw conveyor and are discharged to a crystallized waste salt tank.

[0034] In one embodiment, the crude salt processing subsystem 21 may include a high-temperature melting furnace, slag cooling equipment, a secondary combustion chamber, waste heat recovery equipment, and flue gas treatment equipment. The high-temperature melting furnace receives the crude salt crystals output from the evaporator crystallizer 10 and melts them into a liquid state. The lower layer of the high-temperature melting furnace is high-temperature molten glass, on which the crude salt crystals are placed. Above the crude salt crystals is a gas phase space containing an oxidant used to oxidize the organic matter in the crude salt. After the crude salt crystals melt, they flow out into a slag discharge and cooling device, which cools the molten salt to a solid state before outputting it. The secondary combustion chamber receives the flue gas generated by the high-temperature melting furnace and performs complete combustion on the flue gas to decompose organic pollutants in the flue gas; The waste heat recovery equipment receives the flue gas after it has been treated in the secondary combustion chamber, and uses a water circulation device to exchange heat with the flue gas to generate steam. The cooled flue gas then enters the flue gas treatment equipment. Flue gas treatment equipment is used to desulfurize and / or deammoneninate cooled flue gas before it is discharged.

[0035] In one embodiment, the waste heat recovery device is connected to the evaporator crystallizer 10 to provide steam to the evaporator crystallizer 10.

[0036] Figure 3 A schematic diagram of an example structure of the crude salt treatment subsystem 21 is shown. (Reference) Figure 3As shown, the system includes a feeding system, a high-temperature melting furnace, a slag discharge cooling device, a secondary combustion chamber, a waste heat recovery boiler, and flue gas treatment equipment. The feeding system delivers crude salt crystals into the furnace chamber of the high-temperature melting furnace, covering the melting section. The lower layer of the furnace is high-temperature molten glass at approximately 1400°C, with crude salt crystals above the glass layer, and a gas phase space above the crystals. The overall furnace temperature of the high-temperature melting furnace is maintained between 600 and 1400°C. Under the action of an oxidant (such as oxygen) within the furnace, the crude salt crystals melt, and the organic matter in the crystals decomposes. After removing the organic matter from the waste salt, the molten waste salt flows out of the high-temperature melting furnace and into the slag discharge cooling device. The slag discharge cooling device cools the molten salt to a solid state, obtaining crude salt crystals, which are then output.

[0037] Organic components are separated from the molten salt in the form of flue gas (pyrolysis gas) and drawn into the secondary combustion chamber under negative pressure. The flue gas containing pyrolysis gas is fully combusted with air, fuel gas, etc. in the secondary combustion chamber. The temperature of the secondary combustion chamber is maintained above 1100℃. The designed residence time of the flue gas in the secondary combustion chamber is greater than 2 seconds, which completely decomposes the organic pollutants in the flue gas.

[0038] The flue gas from the secondary combustion chamber enters the waste heat recovery boiler, which operates in a closed-loop system. Demineralized water supplied by the desalination station is deoxygenated and then pumped into the waste heat boiler by the boiler feedwater pump. The steam generated by the hot flue gas is then supplied as external heat energy. After being cooled by the waste heat boiler, the flue gas enters the flue gas treatment system, where it undergoes cooling, desulfurization, and catalytic ammonia removal before meeting emission standards.

[0039] In one embodiment, the refined salt treatment subsystem 22 includes a salt dissolving tank, a reaction precipitation tank, a filtration device, a freeze crystallization device, and an evaporation device; The salt dissolving tank is used to receive and dissolve the crude salt output from the crude salt treatment subsystem 21. A reaction sedimentation tank is used to deposit insoluble substances in a crude salt solution using precipitants and / or flocculants. The filtration equipment is used to filter the crude salt solution output from the reaction sedimentation tank; The freeze crystallization equipment is used to freeze crystallize the salt solution after filtration by the filter equipment to precipitate sodium sulfate product; The sodium chloride evaporation system receives the salt solution processed by the freeze crystallization equipment and evaporates and crystallizes it to obtain sodium chloride product.

[0040] In a preferred embodiment, the refined salt treatment subsystem 22 may further include: A decarbonization neutralization tank, connected to a reaction sedimentation tank and filtration equipment, is used to decarbonize wastewater before filtration; and / or The mixed salt evaporation system is connected to the sodium chloride evaporation system and is used to further evaporate the wastewater after treatment by the sodium chloride evaporation system 225 to precipitate mixed salts.

[0041] Figure 4 An example structural diagram of the refined salt processing subsystem 22 is shown. Figure 4 As shown, the system includes a salt dissolving tank, a plate and frame filter press, a reaction sedimentation tank, a decarbonization and neutralization tank, an ultrafiltration device, a freeze crystallization system, a sodium chloride evaporation system, and a miscellaneous salt evaporation system. The crude salt crystals (detoxified salt) prepared by the crude salt treatment subsystem 21 are fed into the salt dissolving tank, where demineralized water is added. The crude salt crystals dissolve into a near-saturated solution under the action of the demineralized water and are then fed into the reaction sedimentation tank. The lower layer of sludge then enters the plate and frame filter press.

[0042] In the crude salt treatment subsystem 21, precipitants and flocculants are added to remove impurities. Insoluble matter and heavy metal ions are removed from the sludge, which then enters a plate and frame filter press. The crude salt solution, now free of insoluble matter and heavy metal ions, enters a decarbonization and neutralization tank, and is further filtered through an ultrafiltration system. The filtrate (mother liquor) enters a cryogenic crystallization system, while the filter residue enters a plate and frame filter press. The sludge and filter residue are then filtered to obtain sludge, which is discharged. Sodium sulfate decahydrate is crystallized out. The cryogenic mother liquor enters a sodium chloride evaporation system to evaporate and crystallize sodium chloride. The crystallization mother liquor continues to enter a mixed salt evaporation system to evaporate and crystallize mixed salts, which are then disposed of as hazardous waste by a qualified unit.

[0043] Preferably, the wastewater treatment system 30 includes: Oxidation equipment is used to oxidize organic matter in wastewater; At least one of the following: hydrolysis acidification equipment, anaerobic tank, and two-stage A / O equipment: The hydrolysis acidification equipment is used to hydrolyze and acidify the organic matter in wastewater, with the precipitated sludge discharged into a sludge tank; the anaerobic tank uses anaerobic microorganisms to decompose and transform the organic matter in the wastewater; the two-stage A / O equipment is used to oxidize the organic matter in the wastewater under the action of aerobic microorganisms and remove nitrogenous pollutants from the wastewater through nitrification-denitrification; and The filtration system filters the treated wastewater and outputs freshwater for recycling.

[0044] In a preferred embodiment, the filtration system includes: MBR membrane tanks separate sludge from water in wastewater, and input the supernatant into the RO system; The RO system filters the wastewater again to obtain fresh water and concentrated water, which are then output separately.

[0045] Figure 5 A schematic diagram of an example structure of a wastewater treatment system 30 is shown. (Reference) Figure 5As shown, the wastewater treatment system 30 includes an equalization tank, a photocatalytic oxidation system, a first coagulation sedimentation tank, a hydrolysis acidification tank, a sludge tank, an anaerobic tank, a primary A / O device, a second coagulation sedimentation tank, a secondary A / O device, an MBR membrane tank, an activated carbon filtration system, an RO system, a concentrate tank, and a reclaimed water tank.

[0046] The distillation wastewater first enters a regulating tank, where it is temporarily stored and mixed with wastewater from different time periods to stabilize the concentration of pollutants (such as BOD5, ammonia nitrogen, and pH) and achieve a certain degree of water quality balance. The regulating tank then outputs the balanced wastewater to a photocatalytic oxidation system. This system generates highly oxidizing hydroxyl radicals (·OH), which break down organic matter in the wastewater, improving its biodegradability while oxidizing some of the organic matter. The photocatalytically oxidized wastewater then enters a first coagulation and sedimentation tank for coagulation and sedimentation, followed by a hydrolysis and acidification tank. In this tank, organic matter is hydrolyzed and acidified by microorganisms, and the precipitated sludge is discharged into a sludge tank. The hydrolysis and acidification effluent then enters an anaerobic digester (EGSB), where anaerobic microorganisms (including facultative anaerobic microorganisms) decompose and convert various complex organic substances into substances such as methane and carbon dioxide, resulting in a significant degradation of organic matter. The effluent from the anaerobic tank enters the primary A / O (Anoxic / Oxic) system. The primary A / O system is an abbreviation for the anoxic-aerobic process in wastewater biological treatment. The A / O system includes: an anoxic section (low dissolved oxygen, DO = 0.2-0.5 mg / L) primarily for denitrification (reducing nitrate nitrogen to nitrogen gas N2); and an aerobic section (high dissolved oxygen, DO = 2-4 mg / L) for organic matter degradation, ammonia nitrification (NH3-N → NO3⁻-N), and phosphorus uptake by polyphosphate-accumulating bacteria. The primary A / O system prioritizes the use of raw water carbon sources for efficient denitrification, serving as the main nitrogen removal unit (using readily degradable organic matter in the raw water as a carbon source), focusing on removing ammonia nitrogen (NH3-N) and most of the total nitrogen (TN). The effluent then enters the secondary coagulation and sedimentation tank for coagulation and sedimentation. The effluent from the second coagulation sedimentation tank enters the secondary A / O equipment. The secondary A / O equipment performs deep denitrification and residual pollutant treatment, focusing on removing residual total nitrogen (TN) and residual organic matter from the primary stage, while enhancing overall treatment stability. This includes: Anoxic stage (secondary anoxic): Denitrifying bacteria use carbon sources to reduce NO3⁻-N produced in the secondary aerobic stage to N2, further reducing the total nitrogen concentration; Aerobic stage (secondary aerobic): The small amount of ammonia nitrogen remaining in the effluent from the secondary anoxic stage (possibly from incomplete conversion in the primary stage or produced by microbial metabolism in the secondary anoxic stage) is oxidized to NO3⁻-N; further decomposing recalcitrant COD; and polyphosphate-accumulating bacteria excessively absorb phosphate under aerobic conditions (removed through sludge discharge).

[0047] The anaerobic effluent from the anaerobic tank passes through a two-stage A / O biological system. Under the action of aerobic microorganisms, organic matter is oxidized and removed, while nitrogen pollutants are removed through nitrification and denitrification. The effluent from the secondary A / O unit enters the MBR (Membrane Bio-Reactor) membrane tank. The MBR membrane tank achieves sludge-water separation through filtration. The supernatant enters an activated carbon filtration system, and after activated carbon filtration, it enters an RO (Reverse Osmosis) system. The RO system separates the wastewater into freshwater and concentrate. The freshwater enters a reclaimed water tank, which can be used, for example, as cooling water makeup. The concentrate enters a concentrate tank, and can then be transferred to an evaporator crystallizer for evaporative desalination.

[0048] By employing the apparatus provided in this embodiment of the invention, saline organic wastewater is subjected to evaporation and crystallization, high-temperature melting treatment, and salt-nitrate separation and crystallization to obtain sodium chloride and sodium sulfate. The wastewater generated from evaporation and crystallization is subjected to biological treatment and oxidation treatment to remove organic matter from the wastewater. After filtration, fresh water and concentrated water are output, thereby achieving efficient separation and recovery of salts, optimizing the treatment process, and reducing energy consumption and treatment costs. The wastewater is deeply treated to achieve standard reuse, avoiding environmental pollution and having significant environmental benefits. Example 2

[0049] Based on the same technical concept as in Example 1, this embodiment of the invention provides a method for the resource utilization of saline organic waste liquid, applied to the apparatus provided in Example 1 and any preferred embodiment thereof, with reference to... Figure 6 As shown, the method includes: Step 601: Evaporate and crystallize the salt-containing organic waste liquid to obtain crude salt crystals and wastewater; Step 602: The crude salt crystals are subjected to high-temperature melting treatment to obtain crude salt crystals, and the crude salt crystals are subjected to salt-nitrate separation and crystallization separation to obtain sodium chloride salt and sodium sulfate salt; Step 603: The wastewater is subjected to biological and oxidation treatment to output fresh water.

[0050] In a preferred embodiment, before evaporating and crystallizing the saline organic waste liquid, the method further includes: allowing the saline organic waste liquid to stand to achieve oil-water separation, removing the upper layer of oil impurities, and obtaining the saline organic waste liquid.

[0051] Refer to the above Figures 1-5 The method for resource utilization of saline organic waste liquid provided by the present invention includes: 1) Preprocessing stage High-salt organic waste liquid is pumped into a settling tank and left to stand for 24 to 48 hours to allow the oil and water in the waste liquid to separate naturally.

[0052] Subsequently, the upper light oil is collected into an oil tank through a dedicated pipeline and can be used as fuel oil for the secondary combustion chamber of the high-temperature melting system.

[0053] 2) Salt crystallization and recovery stage The evaporator crystallizer uses an MVR (Mechanical Vacuum Recompression) film evaporator. By controlling the evaporation temperature at 35-90℃ and maintaining the vacuum in the evaporation chamber at 40-85 kPa, approximately 90% of the water is evaporated, while salt and high-boiling-point organic matter precipitate out, resulting in crude salt crystals with a solid water content of 5%–15%. The precipitated crude salt crystals are fed into a melting furnace, and the evaporated wastewater is sent to a regulating tank for further treatment. Alternatively, a low-temperature steam scraped-plate evaporator crystallizer or a heat pump scraped-plate evaporator crystallizer can also be used.

[0054] Salt recovery: Organic matter in crude salt is removed through high-temperature melting to obtain detoxified salt. After being dissolved in demineralized water, the detoxified salt enters the refining system, where it undergoes salt-nitrate separation, crystallization separation, and drying processes in sequence to finally obtain regenerated sodium chloride and mirabilite.

[0055] 3) Wastewater treatment and reuse In addition to producing crude salt crystals, the evaporator crystallizer also produces wastewater. This wastewater is treated using a process combining advanced catalytic oxidation, biological treatment, and reverse osmosis membranes to achieve reuse standards. The treated wastewater can be entirely reused as makeup water for the cooling circulation system in the high-temperature melting process.

[0056] The specific implementation of each step of the method provided in this embodiment can be found in the implementation details in Embodiment 1 above, and will not be repeated here.

[0057] Compared with the prior art, the method provided by the embodiments of the present invention has at least the following advantages: Resource recycling: It achieves efficient separation and recovery of salt and utilization of some organic matter, transforming waste into valuable resources, improving resource utilization rate, and generating economic benefits.

[0058] Reduced processing costs: By using technologies such as vapor compression recirculation and low-temperature evaporation, the processing process has been optimized, reducing energy consumption and processing costs.

[0059] Reduce secondary pollution: Deeply treated wastewater ensures it meets standards for reuse, avoiding environmental pollution and yielding significant environmental benefits.

[0060] By employing the method provided in this embodiment of the invention, saline organic wastewater is subjected to evaporation crystallization, high-temperature melting treatment, and salt-nitrate separation and crystallization separation to obtain sodium chloride and sodium sulfate. The wastewater generated from evaporation crystallization is then subjected to biological and oxidation treatment to remove organic matter. After filtration using a filtration device, fresh water and concentrated water are output, thereby achieving efficient separation and recovery of salts, optimizing the treatment process, and reducing energy consumption and treatment costs. The wastewater is deeply treated to achieve compliant reuse, avoiding environmental pollution and demonstrating significant environmental benefits.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for the resource utilization of saline organic waste liquid, characterized in that, It includes an evaporator crystallizer (10), a salt treatment system (20), and a wastewater treatment system (30); among which Evaporator crystallizer (10) is used to receive salt-containing organic waste liquid, evaporate the salt-containing organic waste liquid in the evaporation chamber, and output crude salt crystals and wastewater; The salt treatment system (20) includes a crude salt treatment subsystem (21) and a refined salt treatment subsystem (22). The crude salt treatment subsystem (21) receives crude salt crystals and performs high-temperature melting treatment to obtain crude salt crystals. The refined salt treatment subsystem (22) performs salt-nitrate separation and crystallization separation on the crude salt crystals to obtain sodium chloride salt and sodium sulfate salt. The wastewater treatment system (30) receives the wastewater output from the evaporator crystallizer (10), performs biological and oxidation treatment on the wastewater to remove organic matter, and outputs fresh water after filtration using a filtration device.

2. The apparatus for resource utilization of saline organic waste liquid according to claim 1, characterized in that, It also includes an oil separator (10) for storing salt-containing organic waste liquid, allowing it to stand to achieve oil-water separation of the salt-containing organic waste liquid, and transporting the lower layer of salt-containing organic waste liquid to the evaporator crystallizer (20).

3. The apparatus for resource utilization of saline organic waste liquid according to claim 1, characterized in that, The crude salt processing subsystem (21) includes a high-temperature melting furnace, slag cooling equipment, a secondary combustion chamber, waste heat recovery equipment, and flue gas treatment equipment; The process involves a high-temperature melting furnace that receives crude salt crystals from an evaporator crystallizer and melts them into a liquid state. The lower layer of the furnace is high-temperature molten glass, on which the crude salt crystals are placed. Above the crystals is a gas phase space containing an oxidant used to oxidize the organic matter in the crude salt. After melting, the molten salt crystals flow out into a slag cooling device, which cools the molten salt to a solid state before outputting it. The secondary combustion chamber receives the flue gas generated by the high-temperature melting furnace and performs complete combustion on the flue gas to decompose organic pollutants in the flue gas; The waste heat recovery equipment receives the flue gas after it has been treated in the secondary combustion chamber. It uses a water circulation device to exchange heat with the flue gas to generate steam. The cooled flue gas then enters the flue gas treatment equipment. Flue gas treatment equipment is used to desulfurize and / or remove ammonia from cooled flue gas before it is discharged.

4. The apparatus for resource utilization of saline organic waste liquid according to claim 3, characterized in that, The waste heat recovery equipment is connected to the evaporator crystallizer to provide steam for the evaporator crystallizer.

5. The apparatus for resource utilization of saline organic waste liquid according to any one of claims 1-3, characterized in that, The refined salt processing subsystem (22) includes a salt dissolving tank, a reaction sedimentation tank, a filtration device, a freeze crystallization device, and an evaporation device; The salt dissolving tank is used to receive and dissolve the crude salt output from the crude salt treatment subsystem (21); A reaction sedimentation tank is used to deposit insoluble substances in a crude salt solution using precipitants and / or flocculants. The filtration equipment is used to filter the crude salt solution output from the reaction sedimentation tank; The freeze crystallization equipment is used to freeze crystallize the salt solution after filtration by the filtration equipment to precipitate sodium sulfate product; The sodium chloride evaporation system receives the salt solution processed by the freeze crystallization equipment and evaporates and crystallizes it to obtain sodium chloride product.

6. The apparatus for resource utilization of saline organic waste liquid according to claim 5, characterized in that, Also includes: The decarbonization neutralization tank connects the reaction sedimentation tank and the filtration equipment, and is used to decarbonize wastewater before the filtration equipment. and / or The mixed salt evaporation system is connected to the sodium chloride evaporation system and is used to further evaporate the wastewater after it has been treated by the sodium chloride evaporation system, thereby precipitating mixed salts.

7. The apparatus for resource utilization of saline organic waste liquid according to any one of claims 1-3, characterized in that, The wastewater treatment system (30) includes: Oxidation equipment is used to oxidize organic matter in wastewater; At least one of the following: hydrolysis acidification equipment, anaerobic tank, and two-stage A / O equipment: The hydrolysis acidification equipment is used to hydrolyze and acidify the organic matter in wastewater, with the precipitated sludge discharged into a sludge tank; the anaerobic tank uses anaerobic microorganisms to decompose and transform the organic matter in the wastewater; the two-stage A / O equipment is used to oxidize the organic matter in the wastewater under the action of aerobic microorganisms and remove nitrogenous pollutants from the wastewater through nitrification-denitrification; and The filtration system filters the treated wastewater and outputs freshwater for recycling.

8. The apparatus for resource utilization of saline organic waste liquid according to claim 7, characterized in that, The filtration system includes: MBR membrane tanks separate sludge from water in wastewater, and input the supernatant into the RO system; The RO system filters the wastewater again to obtain fresh water and concentrated water, which are then output separately.

9. A method for the resource utilization of saline organic waste liquid, applied to the apparatus according to any one of claims 1-8, characterized in that, include: The saline organic waste liquid is subjected to evaporation and crystallization treatment to obtain crude salt crystals and wastewater. The crude salt crystals are subjected to high-temperature melting treatment to obtain crude salt crystals, and the crude salt crystals are subjected to salt-nitrate separation and crystallization separation to obtain sodium chloride salt and sodium sulfate salt; Wastewater is treated biologically and through oxidation to produce fresh water.

10. The method for resource utilization of saline organic waste liquid according to claim 9, characterized in that, Before evaporating and crystallizing the saline organic waste liquid, the process also includes: allowing the saline organic waste liquid to stand to achieve oil-water separation, removing the upper layer of oily impurities, and obtaining the saline organic waste liquid.

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