Organic wastewater treatment system and method based on open absorption heat pump principle

Abstract

The application discloses an organic wastewater treatment system and method based on an open absorption heat pump principle, and relates to the technical field of industrial wastewater treatment. The system comprises a heat treatment device, a radiant heat recovery device, a flue gas heat extractor, a condensate heater, a condenser, a separation tank, a centrifuge, a crystallizer, a heater, a concentration tower, a regeneration tower, a condensate cooler, a condensate heat recovery device, a condensate spray tower and a condensate oil removal tank. The system provided by the application can realize classified and efficient treatment of organic wastewater and inorganic wastewater without additional consumption of effective energy.

Description

Technical Field

[0001] This invention relates to the field of industrial wastewater treatment technology, and more specifically, to an organic wastewater treatment system and method based on the principle of an open absorption heat pump. Background Technology

[0002] As the core carrier of industrial production, the harmless treatment and resource utilization of industrial wastewater in industrial parks are key issues for ecological environmental protection and sustainable development. In particular, fine chemical industrial parks are home to a large number of fine chemical enterprises, and the wastewater generated during the production process is extremely complex in composition. It includes organic wastewater containing pollutants such as organic solvents, phenols, and aromatics, as well as inorganic wastewater containing heavy metal ions and inorganic salts. Moreover, the concentration of various types of wastewater fluctuates greatly and is highly toxic. Conventional biological and physicochemical treatment processes in ordinary sewage treatment plants are difficult to achieve effective degradation and compliance with discharge standards, which has become a prominent bottleneck restricting the green development of fine chemical industrial parks.

[0003] In some areas, due to a lack of standardized treatment conditions, unsorted mixed wastewater is entrusted to enterprises equipped with incinerators or kilns for direct spraying into the flue of the incinerator / kiln, attempting to achieve oxidative decomposition of the wastewater through high temperature. However, this treatment method has significant drawbacks: First, a large number of organic pollutants (especially oily organic matter) in the mixed wastewater are prone to pyrolysis and polymerization reactions in the high-temperature environment of the flue, combining with dust and inorganic salts in the flue gas to form sticky clumps that adhere to the inner wall of the flue. This not only blocks the flue and reduces heat exchange efficiency, but also increases equipment operation and maintenance costs and safety hazards, and may also lead to excessive flue gas emissions. Second, directly spraying the mixed wastewater without separate treatment of organic and inorganic wastewater means that it is impossible to recover and utilize organic resources such as oily substances, and the accumulation of salts and heavy metals in the inorganic wastewater in the flue further aggravates the clumping problem. Third, the existing treatment process relies solely on the conventional heating of the incinerator / kiln and does not utilize the waste heat generated therefrom. The treatment process requires additional effective energy consumption, which does not conform to the industrial orientation of energy conservation and emission reduction.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide an organic wastewater treatment system and method based on the principle of open absorption heat pump, thereby solving the technical problems such as flue gas caking, energy waste, and low resource recovery rate caused by the mixed treatment of organic and inorganic wastewater in chemical industrial parks, and achieving efficient treatment of organic and inorganic wastewater in a classified manner without consuming additional effective energy.

[0006] This invention is implemented as follows: In a first aspect, the present invention provides an organic wastewater treatment system, comprising: a heat treatment device, a radiant heat recovery unit, a flue gas heat exchanger, a condensate heater, a condenser, a separation tank, a centrifuge, a crystallizer, a heater, a concentration tower, a regeneration tower, a condensate cooler, a condensate regenerator, a condensate spray tower, and a condensate oil removal tank. The radiant heat recovery unit is disposed on the outer shell of the heat treatment device. The heat treatment device has an inorganic wastewater inlet, an oily substance inlet, a fresh air inlet, and a flue gas outlet. The oily substance inlet is connected to the condensate oil removal tank. The fresh air inlet is connected to the condensate spray tower. The flue gas outlet is connected to the flue gas heat exchanger; the radiant heat recovery unit has a circulating water inlet and a circulating water outlet, the circulating water outlet is connected to the crystallizer, the crystallizer, the condensate heater, the flue gas heat exchanger, and the heater all have circulating water pipelines, the circulating water outlet pipeline of the flue gas heat exchanger is connected to the circulating water inlet of the radiant heat recovery unit; the circulating water outlet pipeline of the crystallizer is connected to the inlet of the condensate heater and the inlet of the heater; the circulating water outlet pipeline of the heater and the circulating water outlet pipeline of the condensate heater merge and connect to the circulating water inlet pipeline of the flue gas heat exchanger. The concentration tower has an organic wastewater inlet, an organic wastewater circulation inlet, an organic wastewater circulation outlet, a concentrated organic wastewater outlet, an air inlet, and an air outlet. The organic wastewater circulation outlet is connected to a heater, which is connected to the organic wastewater circulation inlet via a pipeline. The air outlet and air inlet of the concentration tower are connected to a regeneration tower, respectively. The concentrated organic wastewater outlet is connected to a crystallizer. The crystallizer and the separation tank are connected via a pipeline. The top of the separation tank has a steam outlet connected to a condenser, and the bottom of the separation tank is connected to a centrifuge. The condenser has a condensate outlet that connects to the condensate pipe of the condensate heater and is connected to the condensate spray tower. The condensate spray tower has a condensate outlet that connects to the condensate regenerator. The condensate regenerator has a condensate outlet that connects to the condensate heater. The regeneration tower has a condensate circulating liquid outlet that is sequentially connected to the condensate regenerator, the condensate cooler and the regeneration tower; the regeneration tower is connected to the condensate oil removal tank through a first condensate oil removal pipeline, the condensate oil removal tank has an oil outlet that is connected to the heat treatment device, the condensate oil removal tank has a condensate outlet that is connected to the condensate spray tower, and the condensate oil removal tank also has a second condensate oil removal pipeline that is connected to the condenser. The condensate spray tower has a fresh air inlet and a fresh air outlet, and the fresh air outlet is connected to the fresh air inlet of the heat treatment unit.

[0007] This invention roughly distinguishes between organic and inorganic wastewater. Utilizing the waste heat from existing heat treatment equipment, inorganic wastewater from the factory is directly introduced into the heat treatment device for flue gas atomization spraying, causing direct evaporation. Organic wastewater is then concentrated through a concentration tower, followed by crystallization. After concentration, a large amount of volatile organic compounds or associated substances are carried to the condensate side by the circulating air in the concentration tower. The condensate, after condensation in the condenser, passes through a condensate oil removal tank. The top oily substances are removed by co-firing, while the bottom condensate is vaporized in a condensate spray tower and introduced into the fresh air, achieving zero wastewater discharge and comprehensive utilization of waste heat.

[0008] To achieve efficient concentration and crystallization of the organic wastewater heated in the thickening tower, a high-temperature circulating water system from a radiant heat recovery unit is installed. This system first introduces the high-temperature circulating water into the crystallizer via a circulating water pipeline, heating the concentrated organic wastewater from the thickening tower to obtain secondary steam and the remaining concentrated organic wastewater. The secondary steam is condensed in a condenser and then de-oiled in a condensate oil removal tank. The remaining condensate is heated in a condensate spray tower to form steam, which is then carried into the heat treatment unit for evaporation. The oily substances separated in the condensate oil removal tank are then co-calcined in the heat treatment unit for removal. The remaining concentrated organic wastewater separated in the separation tank can be centrifuged to obtain crystals.

[0009] The secondary circulating water from the crystallizer enters the condensate heater and the heater, respectively, for heating the condensate and raising the temperature of the organic wastewater. The circulating water from the condensate heater and the heater, after heat exchange, merges and is introduced into the flue gas heat exchanger to recover heat from the high-temperature flue gas in the heat treatment unit, thus initially raising the temperature of the circulating water. It then enters the radiant heat recovery unit for further recovery of its waste heat. This achieves integrated wastewater treatment—concentration, separation, crystallization, secondary steam condensation, oil removal, and water removal—without consuming additional energy.

[0010] The condensate oil removal tank includes an external oil sludge pump, an auxiliary oil storage tank, a condensate discharge pump, and an internal guide rod and float. One end of the float is slidably connected to the guide rod, which has at least one fixed end face that is fixedly connected to the inner wall of the tank. The float is provided with an oil inlet and an oil outlet. The oil outlet is connected to the external auxiliary oil storage tank through a pipe. The auxiliary oil storage tank is connected to the oil sludge pump through a pipe. The oil sludge outlet of the oil sludge pump is connected to the oily inlet of the heat treatment device. The condensate discharge pump is connected to the tank, and the liquid outlet of the condensate discharge pump is connected to the condensate spray tower. The condensate oil removal tank has a liquid inlet. One branch of the liquid inlet is connected to the first condensate oil removal pipeline of the regeneration tower, and the other branch of the liquid inlet is connected to the second condensate oil removal pipeline of the condenser.

[0011] The outer wall of the float has a groove, and the guide rod has a slide rail on the side near the float. The groove and the slide rail engage to allow the float to move up and down along the slide rail on the guide rod. Inside the condensate oil removal tank, the float rises or falls with the liquid level, so the oil inlet of the float is always above the liquid surface, collecting only oily substances (oil, being less dense than water, floats). One end of the float is slidably connected to the guide rod, allowing only vertical movement. It is connected to an auxiliary oil storage tank via a hose, and an oil pump continuously discharges the oily liquid.

[0012] The aforementioned heat treatment equipment is selected from: kilns, waste incinerators, cement furnaces, biomass boilers, alkali furnaces, wastewater incinerators, sludge incinerators, rotary dryers, disc dryers, fluidized bed heat equipment, rotary heat equipment (such as rotary drum dryers, rotary calciners, thin-layer dryers), fixed bed heat equipment, or special heat source equipment.

[0013] In a preferred embodiment of the present invention, the centrifuge has a liquid outlet connected to a separation tank, thereby recirculating the concentrated organic wastewater obtained by centrifugation into the separation tank, which then returns the wastewater to the crystallizer for evaporation. The resulting secondary steam and the concentrated organic wastewater are then separated again, and the above steps are repeated to efficiently treat the oily substances and water in the organic wastewater.

[0014] In a preferred embodiment of the present invention, the flue gas heat exchanger includes a kiln head flue gas heat exchanger and a kiln tail flue gas heat exchanger. Both the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger have a circulating water inlet, a circulating water outlet, a flue gas inlet, and a flue gas outlet. The circulating water inlet of the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger are connected to the circulating water inlet pipe of the flue gas heat exchanger, and the circulating water outlet of the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger are connected to the circulating water outlet pipe.

[0015] In a preferred embodiment of the present invention, the condensate cooler has a cooling water inlet and an outlet. The cooling water inlet is used to input cooling water to be heated by heat exchange.

[0016] Secondly, the present invention provides a method for treating organic wastewater based on the above-mentioned organic wastewater treatment system, which includes the following steps: The organic wastewater to be treated is introduced into the thickening tower for spraying, heated by the heater and then transported to the thickening tower for organic wastewater circulation. The heated organic wastewater is output to the crystallizer and heated by the circulating water. In the separation tank, it is separated into secondary steam and bottom concentrated wastewater. The concentrated wastewater is then sent to the centrifuge to produce crystals, and the secondary steam is condensed in the condenser. The condensed water enters the condensate oil removal tank for oil removal, and the oily substances are then fed into the heat treatment unit for co-firing. The remaining condensate after oil removal enters the condensate spray tower for circulation and concentration. In the condensate spray tower, the condensate directly contacts the fresh air for heat and mass transfer, thereby reducing the amount of condensate by evaporation. After heat and mass transfer, the condensate is heated in three stages: condensate regenerator, condenser, and condensate heater, before entering the condensate spray tower to form a cycle.

[0017] In a preferred embodiment of the present invention, the treatment method further includes a circulating air process, which includes: after absorbing heat and moisture in a concentration tower, entering a regeneration tower, directly contacting the sprayed circulating condensate, transferring heat and moisture to the circulating condensate, and then returning to the concentration tower to continue heat and mass transfer with the wastewater, in a continuous cycle.

[0018] In a preferred embodiment of the present invention, the treatment method further includes a circulating water process, which includes: the circulating water from the radiant heat recovery unit enters the crystallizer and exchanges heat with the concentrated organic wastewater, then enters the heater and the condensate heater to heat the organic wastewater and condensate respectively, and the circulating water from the heater and the condensate heater merges and enters the flue gas heat exchanger to exchange heat with the flue gas, and then enters the radiant heat recovery unit to realize the circulating water.

[0019] In a preferred embodiment of the present invention, the treatment method further includes a circulating condensate process, which includes: the circulating condensate absorbs heat and moisture from the humidified air in the regeneration tower, releases heat through the condensate regenerator and condensate cooler, the condensate in the regeneration tower is discharged into the condensate oil removal tank for oil removal, the oily substances are burned in the furnace, and the remaining condensate enters the spray tower, is first heated in three stages by the condensate regenerator, condenser and condensate heater, and then comes into contact with the fresh air entering the condensate spray tower to evaporate into water vapor.

[0020] Thirdly, the present invention also provides the application of an organic wastewater treatment system in wastewater treatment.

[0021] This invention can treat organic wastewater containing pollutants such as organic solvents, phenols, and aromatics, as well as inorganic wastewater containing heavy metal ions and inorganic salts.

[0022] The present invention has the following beneficial effects: This invention provides a treatment system capable of zero discharge of organic wastewater. Before entering the system, the wastewater from the factory is separated into organic and inorganic wastewater based on its type. Utilizing the waste heat from existing heat treatment equipment, the inorganic wastewater is directly introduced into the heat treatment unit for flue gas atomization spraying, causing direct evaporation. The organic wastewater, however, is concentrated in a thickening tower and then crystallized using the waste heat from the heat treatment unit absorbed by the circulating water. After concentration, a large amount of volatile organic compounds or associated substances are carried to the condensate side by the circulating air in the thickening tower. The condensate, after condensation in the condenser, passes through a condensate oil removal tank. The oily substances at the top are removed by co-firing, while the bottom condensate is vaporized in a condensate spray tower and introduced into the fresh air, achieving zero wastewater discharge and comprehensive utilization of waste heat. The organic wastewater treatment system provided by this invention completely solves the technical problems of flue gas agglomeration, energy waste, and low resource recovery rate caused by the mixed treatment of organic and inorganic wastewater. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is one of the structural schematic diagrams of the organic wastewater treatment system provided by the present invention; Figure 2 This is the second schematic diagram of the organic wastewater treatment system provided by the present invention; Figure 3 This is one of the structural schematic diagrams of a condensate oil removal tank; Figure 4 This is the second structural schematic diagram of the condensate oil removal tank; Figure 5 This is a schematic diagram of the structure of the pontoon and guide rod.

[0025] Figure Descriptions: 1-Heat treatment device; 2-Radiant heat recovery unit; 3-Kiln head flue gas heat exchanger; 4-Kiln tail flue gas heat exchanger; 5-Concentration tower; 6-Heater; 7-Condensate heater; 8-Condenser; 9-Separation tank; 10-Centrifuge; 11-Crystallizer; 12-Regeneration tower; 13-Condensate spray tower; 14-Condensate oil removal tank; 15-Condensate regenerator; 16-Condensate cooler; 17-First condensate oil removal pipeline; 18-Second condensate oil removal pipeline; 19-Liquid inlet; 20-Observation window; 21-Guide rod; 22-Oil storage tank; 23-Oil pump; 24-Condensate discharge pump; 25-Float; 26-Hose; 27-Slide rail; 28-Slot. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0029] In the description of this invention, it should be noted that the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0030] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0031] Example 1 This embodiment provides an organic wastewater treatment system, referring to... Figure 1 and Figure 2 As shown, it includes: a heat treatment unit 1, a radiant heat recovery unit 2, a flue gas heat exchanger, a condensate heater 7, a condenser 8, a separation tank 9, a centrifuge 10, a crystallizer 11, a heater 6, a concentration tower 5, a regeneration tower 12, a condensate cooler 16, a condensate regenerator 15, a condensate spray tower 13, and a condensate oil removal tank 14. The heat treatment unit 1 is a kiln or an incinerator.

[0032] Before entering the treatment system, the wastewater from the factory is classified into organic and inorganic wastewater based on its type. Utilizing the waste heat from existing kilns or incinerators, the inorganic wastewater is directly introduced into the heat treatment unit 1 for flue gas atomization spraying, allowing it to evaporate directly. The organic wastewater, however, is concentrated in the concentration tower 5. After concentration, it goes to the crystallizer 11 to crystallize using the waste heat from the heat treatment unit 1 absorbed by the circulating water. After concentration, a large amount of volatile organic compounds or associated substances are carried to the condensate side by the circulating air in the concentration tower 5. The condensate, after condensation in the condenser 8, passes through the condensate oil removal tank 14. The oily substances at the top are removed by co-firing, while the condensate at the bottom goes to the condensate spray tower 13 for vaporization and then into the fresh air, achieving zero wastewater discharge and comprehensive utilization of waste heat.

[0033] Specifically, the radiant heat recovery unit 2 is installed on the outer shell of the heat treatment device 1 to recover heat from the heat treatment device 1. The radiant heat recovery unit 2 can directly heat the incoming circulating water, and then directly export the heated circulating water to the crystallizer 11. After heat exchange, the circulating water flows back to the radiant heat recovery unit 2 to absorb heat again, thus realizing the circulation of the circulating water.

[0034] The heat treatment device 1 has an inorganic wastewater inlet, an oily substance inlet, a fresh air inlet, and a flue gas outlet. The oily substance inlet is connected to the condensate oil removal tank 14. The fresh air inlet is connected to the condensate spray tower 13, and the flue gas outlet is connected to the flue gas heat exchanger. The radiant heat recovery unit 2 has a circulating water inlet and a circulating water outlet. The circulating water outlet is connected to the crystallizer 11. The crystallizer 11, the condensate heater 7, the flue gas heat exchanger, and the heater 6 all have circulating water pipelines. The circulating water outlet pipeline of the flue gas heat exchanger is connected to the circulating water inlet of the radiant heat recovery unit 2. The crystallizer 11 has a circulating water outlet connected to the inlet of the condensate heater 7 and the inlet of the heater 6. The circulating water outlet pipeline of the heater 6 and the circulating water outlet pipeline of the condensate heater 7 merge and connect to the circulating water inlet pipeline of the flue gas heat exchanger.

[0035] Higher-temperature circulating water flows out from the circulating water outlet of the radiant heat recovery unit 2, enters the crystallizer 11 through the circulating water pipeline, and heats the concentrated organic wastewater in the crystallizer 11. The circulating water after heat exchange exits through two paths: one path enters the condensate heater 7 for heating the condensate; the other path enters the heater 6 for heating the organic wastewater. The circulating water after heat exchange exits from the condensate heater 7 and the heater 6, merges, and enters the circulating water inlet pipeline of the flue gas heat exchanger to absorb heat from the high-temperature flue gas. Then, it enters the circulating water inlet of the radiant heat recovery unit 2 through the outlet pipeline of the flue gas heat exchanger.

[0036] To fully recover heat from the flue gas, this embodiment includes a kiln head flue gas heat exchanger 3 and a kiln tail flue gas heat exchanger 4. Both the kiln head and kiln tail flue gas heat exchangers 3 and 4 have a circulating water inlet, a circulating water outlet, a flue gas inlet, and a flue gas outlet. The circulating water inlets of the kiln head and kiln tail flue gas heat exchangers 3 and 4 are connected to the circulating water inlet pipe of the flue gas heat exchanger, and the circulating water outlets of the kiln head and kiln tail flue gas heat exchangers 4 are connected to the circulating water outlet pipe of the flue gas heat exchanger.

[0037] The circulating water process is as follows: the intermediate circulating water takes heat from three locations: the kiln head flue gas heat exchanger 3, the kiln tail flue gas heat exchanger 4, and the radiant heat exchanger, and releases heat at three locations: the condensate heater 7, the heater 6, and the crystallizer 11, thus realizing heat transfer between the walls.

[0038] Concentrator 5 has an organic wastewater inlet, an organic wastewater circulation inlet, an organic wastewater circulation outlet, a concentrated organic wastewater outlet, an air inlet, and an air outlet. Organic wastewater concentration is achieved in concentrator 5.

[0039] The organic wastewater circulation outlet is connected to heater 6, which is connected to the organic wastewater circulation inlet via a pipe. Before spraying, the organic wastewater undergoes indirect heat exchange with the hot circulating water in heater 6 to raise its temperature. Within the concentration tower 5, it is continuously sprayed and comes into direct contact with the circulating air. After heat and mass transfer, the temperature decreases, and the water evaporates, thus achieving concentration. The entire process transfers water to the air in the form of steam. A small amount of concentrated organic wastewater is then discharged to crystallizer 11 for secondary heating and crystallization.

[0040] The concentrated organic wastewater outlet is connected to crystallizer 11; crystallizer 11 and separator 9 are connected by a pipeline for circulation. Separator 9 has a steam outlet at its top connected to condenser 8, and a centrifuge 10 at its bottom. Centrifuge 10 has a liquid outlet connected to separator 9. The concentrated organic wastewater circulates between crystallizer 11 and separator 9. In crystallizer 11, it is heated by the intermediate circulating water. In separator 9, it is separated into secondary steam and concentrated wastewater at the bottom. The concentrated wastewater then goes to centrifuge 10 to produce crystals. The secondary steam goes to condenser 8 for condensation.

[0041] The condenser 8 has a condensate outlet that connects to the condensate pipe of the condensate heater 7 and is then connected to the condensate spray tower 13. After being sprayed in the condensate spray tower 13, the condensate comes into contact with fresh air, and the moisture is carried away by the fresh air.

[0042] The condenser 8 is also connected to the condensate oil removal tank 14 via the second condensate oil removal pipeline 18, thereby removing oil from the condensed organic wastewater. The condensate spray tower 13 has a condensate outlet connected to the condensate regenerator 15, and the condensate regenerator 15 has a condensate outlet connected to the condensate heater 7.

[0043] The condensed water enters the condensate oil removal tank 14 for oil removal, and the oily substances are then fed into the heat treatment device for co-firing. The remaining condensate after oil removal enters the condensate spray tower 13 for circulation and concentration. In the condensate spray tower 13, the condensate directly contacts the fresh air for heat and mass transfer, thereby reducing the amount of condensate by evaporation. After heat and mass transfer, the condensate is heated in three stages: condensate regenerator 15, condenser 8, and condensate heater 7, before entering the condensate spray tower 13 to form a cycle.

[0044] The air outlet and air inlet of the concentration tower 5 are connected to the regeneration tower 12. After absorbing heat and moisture in the concentration tower 5, the air temperature and moisture content increase. It then enters the regeneration tower 12 and comes into direct contact with the circulating condensate sprayed on it, transferring heat and moisture to the circulating condensate. After that, it returns to the concentration tower 5 to continue the heat and mass transfer with the wastewater, and the cycle repeats.

[0045] The regeneration tower 12 has a condensate circulating liquid outlet that is sequentially connected to the condensate regenerator 15, the condensate cooler 16, and the regeneration tower 12. The regeneration tower 12 is connected to the condensate oil removal tank 14 via a first condensate oil removal pipeline 17. The condensate oil removal tank 14 has an oil outlet that is connected to the heat treatment device 1, and a condensate outlet that is connected to the condensate spray tower 13. The condensate cooler 16 has a cooling water inlet and an outlet.

[0046] The condensate spray tower 13 has a fresh air inlet and a fresh air outlet, and the fresh air outlet is connected to the fresh air inlet of the heat treatment device 1.

[0047] The circulating condensate process is as follows: After absorbing heat and moisture from the humidified air in the regeneration tower 12, the circulating condensate releases heat sequentially through the condensate regenerator 15 and the condensate cooler 16. Since water vapor in the air continuously turns into condensate, the condensate needs to be continuously discharged into the condensate oil removal tank 14 for oil removal. The oily substances are then mixed and burned in the furnace. The remaining condensate enters the spray tower, where it is first heated in three stages by the condensate regenerator 15, the condenser 8, and the condensate heater 7, and then comes into direct contact with the incoming fresh air, completely evaporating into water vapor before entering the furnace.

[0048] Since the fresh air enters in a gaseous state, it will not affect the combustion efficiency of the furnace. Furthermore, since the spraying will raise the temperature of the fresh air, it will also produce a certain waste heat recovery effect. Sensible heat (i.e. the heat obtained by the fresh air) accounts for about 20% of the total heat and is used to heat the fresh air, while the remaining 80% is used for phase change.

[0049] The structure of the condensate oil removal tank 14 is as follows: Figure 3 and Figure 4As shown, the condensate oil removal tank 14 includes an external oil pump 23, an auxiliary oil storage tank 22, a condensate discharge pump 24, and an internal guide rod 21 and float 25. One side of the float 25 is slidably connected to the guide rod 21, and one fixed end face of the guide rod 21 is fixedly connected to the inner wall of the tank. The outer wall of the float 25 has a groove 28, and the side of the guide rod 21 near the float 25 has a slide rail 27. The groove 28 and the slide rail 27 engage to allow the float 25 to move up and down along the slide rail 27 on the guide rod 21. Figure 5 (As shown).

[0050] The float 25 is equipped with an oil inlet and an oil outlet. The oil outlet is connected to an external oil storage tank 22 via a pipe. The oil storage tank 22 is connected to an oil sludge pump 23 via a pipe. The oil sludge outlet of the oil sludge pump 23 is connected to the oily substance inlet of the heat treatment device 1. The condensate discharge pump 24 is connected to the tank body. The liquid outlet of the condensate discharge pump 24 is connected to the condensate spray tower 13. The condensate oil removal tank 14 has a liquid inlet 19. One branch of the liquid inlet 19 is connected to the first condensate oil removal pipeline 17 of the regeneration tower 12. The other branch of the liquid inlet 19 is connected to the second condensate oil removal pipeline 18 of the condenser 8.

[0051] The condensate oil removal tank 14 also has an observation window 20 to facilitate observation of the liquid level inside the tank.

[0052] The condensate oil removal tank 14 has a float 25 inside, which can rise or fall with the liquid level. Therefore, the water inlet of the float 25 is always on the liquid surface, and it only collects oily substances (oil has a lower density than water and will float). In addition, the float 25 is fixed on the guide rod 21 and can only move up and down. It is connected to the oil storage auxiliary tank 22 through the hose 26. The oil pump 23 works to allow the oily liquid to be continuously discharged.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An organic wastewater treatment system based on the principle of an open-type absorption heat pump, characterized in that, It includes: The system includes a heat treatment unit, a radiant heat recovery unit, a flue gas heat exchanger, a condensate heater, a condenser, a separator, a centrifuge, a crystallizer, a heater, a concentration tower, a regeneration tower, a condensate cooler, a condensate regenerator, a condensate spray tower, and a condensate oil removal tank. The radiant heat recovery unit is installed on the outer shell of the heat treatment unit. The heat treatment unit has an inorganic wastewater inlet, an oily substance inlet, a fresh air inlet, and a flue gas outlet. The oily substance inlet is connected to the condensate oil removal tank. The fresh air inlet is connected to the condensate spray tower, and the flue gas outlet is connected to the flue gas heat exchanger ... The heat recovery unit has a circulating water inlet and a circulating water outlet. The circulating water outlet is connected to the crystallizer. The crystallizer, the condensate heater, the flue gas heat exchanger, and the heater all have circulating water pipelines. The circulating water outlet pipeline of the flue gas heat exchanger is connected to the circulating water inlet of the radiant heat recovery unit. The circulating water outlet pipeline of the crystallizer is connected to the inlet of the condensate heater and the inlet of the heater. The circulating water outlet pipeline of the heater and the circulating water outlet pipeline of the condensate heater merge and connect to the circulating water inlet pipeline of the flue gas heat exchanger. The concentration tower has an organic wastewater inlet, an organic wastewater circulation inlet, an organic wastewater circulation outlet, a concentrated organic wastewater outlet, an air inlet, and an air outlet. The organic wastewater circulation outlet is connected to the heater, and the heater is connected to the organic wastewater circulation inlet via a pipeline. The air outlet and air inlet of the concentration tower are respectively connected to the regeneration tower. The concentrated organic wastewater outlet is connected to the crystallizer. The crystallizer and the separation tank are circulated through a pipeline. The top of the separation tank has a steam outlet connected to the condenser, and the bottom of the separation tank is connected to a centrifuge. The condenser has a condensate outlet that connects to the condensate pipeline of the condensate heater and is connected to the condensate spray tower. The condensate spray tower has a condensate outlet that connects to the condensate regenerator. The condensate regenerator has a condensate outlet that connects to the condensate heater. The regeneration tower has a condensate circulating liquid outlet that is sequentially connected to the condensate regenerator, the condensate cooler, and the regeneration tower; the regeneration tower is connected to the condensate oil removal tank via a first condensate oil removal pipeline, the condensate oil removal tank has an oil outlet that is connected to the heat treatment device, the condensate oil removal tank has a condensate outlet that is connected to the condensate spray tower, and the condensate oil removal tank also has a second condensate oil removal pipeline that is connected to the condenser. The condensate spray tower has a fresh air inlet and a fresh air outlet, and the fresh air outlet is connected to the fresh air inlet of the heat treatment device.

2. The organic wastewater treatment system according to claim 1, characterized in that, The condensate oil removal tank includes an external oil pump, an auxiliary oil storage tank, a condensate discharge pump, and an internal guide rod and float. One end of the float is slidably connected to the guide rod, and the guide rod has at least one fixed end face that is fixedly connected to the inner wall of the tank. The float is provided with an oil inlet and an oil outlet. The oil outlet is connected to the external auxiliary oil storage tank through a pipe. The auxiliary oil storage tank is connected to the oil pump through a pipe. The oil outlet of the oil pump is connected to the oily inlet of the heat treatment device. The condensate discharge pump is connected to the tank and its liquid outlet is connected to the condensate spray tower. The condensate oil removal tank has a liquid inlet. One branch of the liquid inlet is connected to the first condensate oil removal pipeline of the regeneration tower, and the other branch is connected to the second condensate oil removal pipeline of the condenser.

3. The organic wastewater treatment system according to claim 2, characterized in that, The outer wall of the pontoon has a groove, and the guide rod has a slide rail on the side near the pontoon. The groove engages with the slide rail so that the pontoon can move up and down along the slide rail on the guide rod.

4. The organic wastewater treatment system according to claim 1, characterized in that, The centrifuge has a liquid outlet connected to the separation tank, and the condensate cooler has a cooling water inlet and outlet.

5. The organic wastewater treatment system according to claim 1, characterized in that, The flue gas heat exchanger includes a kiln head flue gas heat exchanger and a kiln tail flue gas heat exchanger. Both the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger have a circulating water inlet, a circulating water outlet, a flue gas inlet, and a flue gas outlet. The circulating water inlet of the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger are connected to the circulating water inlet pipe of the flue gas heat exchanger, and the circulating water outlet of the kiln head flue gas heat exchanger and the kiln tail flue gas heat exchanger are connected to the circulating water outlet pipe. The heat treatment device is selected from: kilns, waste incinerators, cement furnaces, biomass boilers, alkali furnaces, wastewater incinerators, sludge incinerators, rotary dryers, disc dryers, fluidized bed heat equipment, rotary heat equipment, fixed bed heat equipment, or special heat source equipment.

6. A method for treating organic wastewater based on the organic wastewater treatment system according to any one of claims 1-5, characterized in that, It includes the following steps: The organic wastewater to be treated is introduced into the thickening tower for spraying, heated by the heater and then transported to the thickening tower for organic wastewater circulation. The heated organic wastewater is output to the crystallizer and heated by the circulating water. In the separation tank, it is separated into secondary steam and bottom concentrated wastewater. The concentrated wastewater is then sent to the centrifuge to produce crystals, and the secondary steam is condensed in the condenser. The condensed water enters the condensate oil removal tank for oil removal, and the oily substances are then fed into the heat treatment unit for co-firing. The remaining condensate after oil removal enters the condensate spray tower for circulation and concentration. In the condensate spray tower, the condensate directly contacts the fresh air for heat and mass transfer, thereby reducing the amount of condensate by evaporation. After heat and mass transfer, the condensate is heated in three stages: condensate regenerator, condenser, and condensate heater, before entering the condensate spray tower to form a cycle.

7. The method for treating organic wastewater using the organic wastewater treatment system according to claim 6, characterized in that, The treatment method also includes a circulating air process, which includes: after absorbing heat and moisture in the concentration tower, entering the regeneration tower, directly contacting the sprayed circulating condensate, transferring heat and moisture to the circulating condensate, and then returning to the concentration tower to continue heat and mass transfer with the wastewater, in a continuous cycle.

8. The method for treating organic wastewater using the organic wastewater treatment system according to claim 6, characterized in that, The treatment method also includes a circulating water process, which includes: the circulating water absorbing the radiant heat recovery unit enters the crystallizer from the radiant heat recovery unit and exchanges heat with the concentrated organic wastewater, then the circulating water enters the heater and the condensate heater to heat the organic wastewater and condensate respectively, and the circulating water coming out of the heater and the condensate heater merges and enters the flue gas heat exchanger to exchange heat with the flue gas, and then enters the radiant heat recovery unit to realize the circulating water.

9. The method for treating organic wastewater using the organic wastewater treatment system according to claim 6, characterized in that, The treatment method also includes a circulating condensate process, which includes: the circulating condensate absorbs heat and moisture from the humid air in the regeneration tower, releases heat through the condensate regenerator and condensate cooler, the condensate in the regeneration tower is discharged into the condensate oil removal tank for oil removal, the oily substances are sent to the furnace for co-firing, and the remaining condensate enters the spray tower, is first heated in three stages by the condensate regenerator, condenser and condensate heater, and then comes into contact with the fresh air entering the condensate spray tower to evaporate into water vapor.

10. The application of the organic wastewater treatment system as described in any one of claims 1-5 in wastewater treatment.

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