Coal-to-ammonia gasification black water comprehensive utilization unit
By combining components such as gasifiers, hydrocyclones, and flash tanks, the waste heat from coal-to-ammonia gasification black water is recovered and reused, solving the problems of waste heat and water resources, and achieving efficient and comprehensive utilization of resources and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XINJIANG XINLIANXIN CHEMICAL IND CO LTD
- Filing Date
- 2026-03-09
- Publication Date
- 2026-06-02
AI Technical Summary
In existing technologies, the treatment of black water from coal-to-ammonia gasification suffers from excessive waste heat loss and water consumption, making it impossible to achieve efficient and comprehensive utilization.
The system employs a combination of components such as a gasifier, a first heat exchanger, a hydrocyclone separator, a first flash tank, a buffer tank, and a washing tower. Through hydrocyclone separation, flash evaporation, and heat exchange processes, it recovers the waste heat from the gasified black water and uses the separated supernatant for system makeup water, reducing the amount of raw water used. It also integrates a turbine and a generator for energy recovery.
It has enabled the recovery and utilization of waste heat from gasification black water, reduced water consumption, solved the problem of insufficient capacity of the park's circulating water system, reduced production costs, and improved resource utilization.
Smart Images
Figure CN122126997A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of waste heat and water resource recovery and utilization technology, and is a comprehensive utilization device for black water from coal-to-ammonia gasification. Background Technology
[0002] Currently, the treatment of black water from coal-to-ammonia gasification typically employs a three-stage flash evaporation process. During the staged flash evaporation and subsequent ash water pressurization process, not only is there a loss of waste heat resources in the system's black water (gasification black water temperature is 220-250℃), but it also requires continuous replenishment of the system with crude coal gas for washing, increasing water resource consumption.
[0003] This paper discloses a waste heat recovery and utilization retrofit of a flash system in a coal slurry gasification unit. Addressing the technical bottleneck of the current four-stage flash system in coal-water slurry gasification units, where the high-pressure flash steam contains 14.7% non-condensable gases, rendering it unusable and resulting in a waste heat utilization rate of less than 52.7% for the entire system. The paper achieves a breakthrough in energy efficiency through process reconfiguration. Optimization of the flash unit reduces high-pressure flash steam output by 9.3 t / h and increases medium-pressure steam output by 19 t / h. A cascade utilization system for medium-pressure steam is established, employing back-pressure turbine power generation technology to recover surplus energy from the medium-pressure flash. After the system retrofit, the comprehensive waste heat utilization rate increases to 75.6%. This can save 24,000 tons of standard coal and reduce CO2 emissions by 61,000 tons annually. The investment payback period is less than 0.73 years, forming an energy efficiency improvement solution with engineering demonstration value. Wen Li, Min Weiwei, Zhao Junfeng, Jin Guiming. Retrofitting of waste heat recovery and utilization in flash evaporation system of coal slurry gasification unit [J]. Chemical Engineering, 2025, 53(12):90-94.
[0004] This paper discloses the preparation and corrosion resistance and thermal conductivity of a composite coating for heat exchanger surfaces. To improve the corrosion resistance of the heat exchanger surface without affecting its heat exchange efficiency, a corrosion-resistant and highly thermally conductive graphene composite coating for use on the heat exchanger surface was prepared using graphene, graphite powder, and epoxy resin as raw materials. The coating was subjected to sulfuric acid corrosion, thermal conductivity, and bonding strength tests. The results showed that the corrosion resistance of the coating increased with increasing graphene content. When the graphene mass fraction reached 0.06%, the corrosion rate of the coating reached its lowest value of 0.2338 mg / (cm³). 2 Its corrosion resistance is far superior to that of 304 stainless steel (1.500 mg / (cm³)). 2 The thermal conductivity of the coating increases with the increase of graphite powder content, and reaches a maximum value of 35.848 W / (m·K) when the mass fraction of graphite powder is 8%; the bonding strength of the coating reaches ASTM grade 5B. Nie Shengnan, Wu Lijun, Liu Yinghan, Zhang Hao. Preparation and corrosion resistance and thermal conductivity of composite coatings on heat exchanger surface [J]. Fine Chemicals, 2020, 37(01):66-71.
[0005] Patent document CN121292714A discloses a multi-stage deep treatment device and method for coal gasification black water, relating to the field of water treatment technology. The device includes a first flash tank, a settling tank, a mixing and clarification tank, a baffle plate, an overflow port, a mixing chamber, a clarification chamber, a stirring mechanism, a pressure plate, a water inlet tank, and a fixed chamber. The fixed chamber has open sides and an adjusting plate that is engaged internally. The adjusting plate slides freely horizontally within the fixed chamber, and the adjusting plate, fixed chamber, and baffle plate form a water storage space. In this invention, the pressure plate moves downwards, squeezing the extract in the mixing chamber. Under pressure, some of the extract enters the water storage space from the water inlet tank. As the pressure plate moves downwards, the extract level in the water storage space rises, causing the extract to flow from the overflow port into the clarification chamber. Since the extract loses the force of the stirring mechanism after entering the water storage space, there is no significant turbulence, allowing it to flow into the clarification chamber at a lower flow rate, thus avoiding affecting the clarification efficiency.
[0006] The existing technologies in the industry mainly optimize black water through a three-stage flash evaporation system, but cannot achieve efficient and comprehensive utilization of gasified black water.
[0007] There is an urgent need in the industry for a comprehensive utilization device for coal-to-ammonia gasification black water, which can not only make full use of the waste heat of gasification black water, but also separate and purify the gasification black water, and then replenish the system with the separated clean water, reducing the amount of water replenished to the system. Summary of the Invention
[0008] This invention provides a device for the comprehensive utilization of black water from coal-to-synthetic ammonia gasification, which overcomes the shortcomings of the prior art and can effectively solve the problem that existing devices and methods cannot efficiently and comprehensively utilize the gasified black water.
[0009] The technical solution of this invention is achieved through the following measures: A coal-to-ammonia gasification black water comprehensive utilization device includes a gasifier, a first heat exchanger, a hydrocyclone separator, a first flash tank, a buffer tank, and a scrubbing tower; the outlet end of the gasifier and the tube-side inlet end of the first heat exchanger are connected together by a first pipeline; the tube-side outlet end of the first heat exchanger and the inlet end of the hydrocyclone separator are connected together by a second pipeline; the supernatant outlet end of the hydrocyclone separator and the inlet end of the scrubbing tower are connected together by a third pipeline; the black water outlet end of the hydrocyclone separator and the inlet end of the first flash tank are connected together by a fourth pipeline; the outlet end of the buffer tank and the shell-side inlet end of the first heat exchanger are connected together by a fifth pipeline; the shell-side outlet end of the first heat exchanger and the return end of the buffer tank are connected together by a sixth pipeline; a pump is installed on the fifth pipeline; a first turbine is installed on the sixth pipeline; and a first generator is connected to the outside of the first turbine.
[0010] The following are further optimizations and / or improvements to the above-mentioned technical solution: The aforementioned first flash tank has a clarification tank and a filter press outside it. The clarification tank has an inlet at the top and an outlet at the bottom. The outlet of the first flash tank and the inlet of the clarification tank are connected together by a seventh pipeline. The clarification tank has a discharge end at the bottom and the discharge end of the clarification tank and the inlet of the filter press are connected together by an eighth pipeline. A pump is installed on the eighth pipeline.
[0011] The first flash tank has a filter cake storage device, a water replenishment tank, and a filtrate buffer tank on its outer side. The filter press has a filter cake outlet and a filtrate outlet. The filter cake outlet of the filter press is connected to the feed end of the filter cake storage device. The filtrate outlet of the filter press and the inlet of the filtrate buffer tank are connected together through a ninth pipeline. A return end is provided at the top of the clarifier. The outlet of the filtrate buffer tank and the return end of the clarifier are connected together through a tenth pipeline. A pump is installed on the tenth pipeline. An overflow end is provided at the top of the clarifier. The overflow end of the clarifier and the inlet of the water replenishment tank are connected together through an eleventh pipeline.
[0012] The above also includes a second heat exchanger and a second flash tank. The top of the first flash tank is provided with an outlet. The outlet of the first flash tank and the tube-side inlet of the second heat exchanger are connected together through the twelfth pipeline. The tube-side outlet of the second heat exchanger and the liquid inlet of the second flash tank are connected together through the thirteenth pipeline. A fourteenth pipeline is connected between the fifth pipeline and the shell-side inlet of the second heat exchanger. A fifteenth pipeline is connected between the shell-side outlet of the second heat exchanger and the sixth pipeline. A second turbine is installed on the fifteenth pipeline. A second generator is connected to the outside of the second turbine.
[0013] The above-mentioned second flash tank has a condensate recovery tank and a coal slurry preparation device on its outer side. The liquid outlet of the second flash tank and the liquid inlet of the condensate recovery tank are connected together through the sixteenth pipeline. The liquid outlet of the condensate recovery tank and the liquid inlet of the coal slurry preparation device are connected together through the seventeenth pipeline. A pump is installed on the seventeenth pipeline.
[0014] The second flash tank is surrounded by a flare tower. The top of the second flash tank is equipped with an outlet. The outlet of the second flash tank and the inlet of the flare tower are connected together by an eighteenth pipeline. A pressure gauge and a valve are installed on the eighteenth pipeline. Or / and, a first power grid is located outside the first generator. The power output of the first generator is connected to the first power grid. Or / and, a second power grid is located outside the second generator. The power output of the second generator is connected to the second power grid.
[0015] A thermometer is installed on the first pipeline, and flow meters are installed on the third, fourth, and twelfth pipelines, respectively.
[0016] Valves are installed on the first, second, third, fourth, fifth, sixth, seventh, eighth, tenth, eleventh, thirteenth, fourteenth, fifteenth, sixteenth and seventeenth pipelines respectively.
[0017] This invention has a reasonable and compact structure and is easy to use. By using the first heat exchanger, cyclone separator, first flash tank, second heat exchanger, first turbine and second turbine in combination, it achieves the purpose of comprehensive resource utilization. On the one hand, it recovers and utilizes the waste heat of gasified black water, and on the other hand, it recycles and reuses the gasified black water itself. This not only solves the problem of insufficient capacity of the park's circulating water system, but also reduces the amount of raw water used and saves water resources, thereby maximizing resource utilization. It has the characteristics of safety and reliability, facilitates operation and greatly reduces production costs. Attached Figure Description
[0018] Appendix Figure 1 This is a schematic diagram of the process flow of the present invention.
[0019] The codes in the attached diagram are as follows: 1 for gasifier, 2 for first heat exchanger, 3 for hydrocyclone separator, 4 for first flash tank, 5 for buffer tank, 6 for scrubbing tower, 7 for first pipeline, 8 for second pipeline, 9 for third pipeline, 10 for fourth pipeline, 11 for fifth pipeline, 12 for sixth pipeline, 13 for pump, 14 for first turbine, 15 for first generator, 16 for clarifier, 17 for filter press, 18 for seventh pipeline, 19 for eighth pipeline, 20 for filter cake storage device, 21 for water replenishment tank, 22 for filtrate buffer tank, 23 for ninth pipeline, 2 4 is the tenth pipeline, 25 is the eleventh pipeline, 26 is the second heat exchanger, 27 is the second flash tank, 28 is the twelfth pipeline, 29 is the thirteenth pipeline, 30 is the fourteenth pipeline, 31 is the fifteenth pipeline, 32 is the second turbine, 33 is the second generator, 34 is the first power grid, 35 is the condensate recovery tank, 36 is the coal slurry preparation unit, 37 is the sixteenth pipeline, 38 is the seventeenth pipeline, 39 is the flare tower, 40 is the eighteenth pipeline, 41 is a pressure gauge, 42 is a valve, 43 is the second power grid, 44 is a thermometer, and 45 is a flow meter. Detailed Implementation
[0020] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.
[0021] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.
[0022] The present invention will be further described below with reference to embodiments and accompanying drawings: As attached Figure 1 As shown, the coal-to-ammonia gasification black water comprehensive utilization device includes a gasifier 1, a first heat exchanger 2, a hydrocyclone separator 3, a first flash tank 4, a buffer tank 5, and a scrubbing tower 6. The outlet end of the gasifier 1 and the tube-side inlet end of the first heat exchanger 2 are connected together by a first pipeline 7. The tube-side outlet end of the first heat exchanger 2 and the inlet end of the hydrocyclone separator 3 are connected together by a second pipeline 8. The supernatant outlet end of the hydrocyclone separator 3 and the inlet end of the scrubbing tower 6 are connected together by a third pipeline 9. The black water outlet of the hydrocyclone 3 and the inlet of the first flash tank 4 are connected together by the fourth pipeline 10; the outlet of the buffer tank 5 and the shell-side inlet of the first heat exchanger 2 are connected together by the fifth pipeline 11; the shell-side outlet of the first heat exchanger 2 and the return end of the buffer tank 5 are connected together by the sixth pipeline 12; a pump 13 is installed on the fifth pipeline 11; a first turbine 14 is installed on the sixth pipeline 12; and a first generator 15 is connected to the outside of the first turbine 14. Gasifier 1, first heat exchanger 2, hydrocyclone separator 3, first flash tank 4, buffer tank 5, and scrubbing tower 6 are all existing and publicly known components. Scrubbing tower 6 can be a crude gas scrubbing tower. Hydrocyclone separator 3 can be a hydrocyclone separator according to GB / T150.1-150.4-2011. Hydrocyclone separator 3 can separate the black water after heat exchange in the first heat exchanger 2, obtaining supernatant and black water. The mass ratio of supernatant to black water can reach 1:0.5-1. The separated supernatant is sent to scrubbing tower 6 to clean the crude gas, and the separated black water is sent to the first flash tank 4 for depressurized flash evaporation. The separated supernatant is equivalent to the water replenishment of this invention, that is, this invention can reduce system water replenishment, reduce raw water consumption, and save water resources. In this way, by using the first heat exchanger 2, the hydrocyclone separator 3, the first flash tank 4 and the first turbine 14 in combination, the goal of comprehensive resource utilization is achieved. On the one hand, the waste heat of the gasified black water is recovered and utilized, and on the other hand, the gasified black water itself is recycled and reused. This not only solves the problem of insufficient capacity of the park's circulating water system, but also reduces the amount of raw water used and saves water resources, thereby maximizing resource utilization. It has the characteristics of safety and reliability, facilitates operation, and greatly reduces production costs.
[0023] The above-mentioned coal-to-ammonia gasification black water comprehensive utilization device can be further optimized and / or improved according to actual needs: As attached Figure 1As shown, a clarifier 16 and a filter press 17 are located outside the first flash tank 4. The clarifier 16 has an inlet at its upper part, and the first flash tank 4 has an outlet at its bottom. The outlet of the first flash tank 4 and the inlet of the clarifier 16 are connected by a seventh pipeline 18. The clarifier 16 has a discharge end at its bottom, and the discharge end of the clarifier 16 and the inlet of the filter press 17 are connected by an eighth pipeline 19. A pump 13 is installed on the eighth pipeline 19. The clarifier 16 can also be a clarification tank.
[0024] As attached Figure 1 As shown, a filter cake storage device 20, a water replenishment tank 21, and a filtrate buffer tank 22 are located outside the first flash tank 4. The filter press 17 has a filter cake outlet and a filtrate outlet, respectively. The filter cake outlet of the filter press 17 is connected to the feed inlet of the filter cake storage device 20. The filtrate outlet of the filter press 17 and the inlet of the filtrate buffer tank 22 are connected together via a ninth pipeline 23. A return end is located at the top of the clarifier 16. The outlet of the filtrate buffer tank 22 and the return end of the clarifier 16 are connected together via a tenth pipeline 24. A pump 13 is installed on the tenth pipeline 24. An overflow end is located at the top of the clarifier 16. The overflow end of the clarifier 16 and the inlet of the water replenishment tank 21 are connected together via an eleventh pipeline 25. Both the filter press 17 and the filter cake storage device 20 are existing and publicly known technologies; the filter press 17 can be a filter press, and the filter cake storage device 20 can be a filter cake storage device.
[0025] As attached Figure 1 As shown, it also includes a second heat exchanger 26 and a second flash tank 27. The top of the first flash tank 4 is provided with an outlet. The outlet of the first flash tank 4 and the tube-side inlet of the second heat exchanger 26 are connected together by the twelfth pipeline 28. The tube-side outlet of the second heat exchanger 26 and the liquid inlet of the second flash tank 27 are connected together by the thirteenth pipeline 29. The fourteenth pipeline 30 is connected between the fifth pipeline 11 and the shell-side inlet of the second heat exchanger 26. The fifteenth pipeline 31 is connected between the shell-side outlet of the second heat exchanger 26 and the sixth pipeline 12. A second turbine 32 is installed on the fifteenth pipeline 31. A second generator 33 is connected to the outside of the second turbine 32. The inner walls of the tube-side and / or shell-side of the first heat exchanger 2 and the second heat exchanger 26 can be coated with a graphene composite coating. The graphene composite coating is prepared from graphene, graphite powder, epoxy resin, etc., wherein the mass fraction of graphene is 4-10%.
[0026] As attached Figure 1As shown, outside the second flash tank 27 are a condensate recovery tank 35 and a coal slurry preparation device 36. The outlet end of the second flash tank 27 and the inlet end of the condensate recovery tank 35 are connected together through the sixteenth pipeline 37. The outlet end of the condensate recovery tank 35 and the inlet end of the coal slurry preparation device 36 are connected together through the seventeenth pipeline 38. A pump 13 is installed on the seventeenth pipeline 38.
[0027] As attached Figure 1 As shown, a flare tower 39 is located outside the second flash tank 27. An outlet is located at the top of the second flash tank 27. The outlet of the second flash tank 27 and the inlet of the flare tower 39 are connected together via an eighteenth pipeline 40. A pressure gauge 41 and a valve 42 are installed on the eighteenth pipeline 40. Alternatively, a first power grid 34 is located outside the first generator 15, and the power output of the first generator 15 is connected to the first power grid 34. Alternatively, a second power grid 43 is located outside the second generator 33, and the power output of the second generator 33 is connected to the second power grid 43. Both the first power grid 34 and the second power grid 43 are part of the park's power grid system, and the electricity generated by the first generator 15 and the second generator 33 can be transmitted to the corresponding park power grid system.
[0028] As attached Figure 1 As shown, a thermometer 44 is installed on the first pipeline 7, and flow meters 45 are installed on the third pipeline 9, the fourth pipeline 10, and the twelfth pipeline 28, respectively.
[0029] As attached Figure 1 As shown, valves 42 are installed on the first pipeline 7, the second pipeline 8, the third pipeline 9, the fourth pipeline 10, the fifth pipeline 11, the sixth pipeline 12, the seventh pipeline 18, the eighth pipeline 19, the tenth pipeline 24, the eleventh pipeline 25, the thirteenth pipeline 29, the fourteenth pipeline 30, the fifteenth pipeline 31, the sixteenth pipeline 37, and the seventeenth pipeline 38, respectively.
[0030] In this invention, the liquid levels of the gasifier 1, clarifier 16, first flash tank 4, hydrocyclone separator 3, and second flash tank 27, and the opening degree of the valves 42 (regulating valves) on the corresponding outlet pipelines can be automatically controlled by a DCS; the liquid levels (20-80%) of the clarifier 16, filtrate buffer tank 22, and condensate recovery tank 35, and the start and stop of the pumps 13 on the corresponding outlet pipelines can be automatically controlled by a DCS; the opening degree of the valve 42 on the fifteenth pipeline 31 and the pressure gauge 41 (gas phase pressure monitoring device) on the gas phase outlet pipeline (eighteenth pipeline 40) of the second flash tank 27 can be automatically controlled by a DCS.
[0031] After separation by hydrocyclone 3, the supernatant and black water obtained can be controlled by valve 42 on the corresponding pipeline. The mass (flow rate) ratio of supernatant to black water can reach 1:0.5-1.
[0032] The working fluid of this invention can be selected from hydrofluoroolefins (HFOs) with excellent environmental performance, good thermal performance, and high safety. All pipes in this invention can be made of stainless steel; all automatic control systems are DCS controlled; temperature, flow rate, and pressure are all monitored and displayed online; the hydrocyclone separator 3 is purchased externally, and its lining uses a graphene composite coating; both the first heat exchanger 2 and the second heat exchanger 26 can be purchased high-efficiency heat exchangers, and their internal channels can use a graphene composite coating; the graphene composite coating is prepared from graphene, graphite powder, epoxy resin, etc., wherein the mass fraction of graphene is 4-10%.
[0033] Advantages of this invention: (1) This invention provides a device that is simple in structure, low in energy consumption, environmentally friendly and green, and can effectively recover the waste heat of coal-to-ammonia gasification black water and reuse the black water.
[0034] (2) On the one hand, the present invention can recycle the waste heat of gasified black water, and on the other hand, it can recycle and reuse the gasified black water itself. This can solve the problem of insufficient capacity of the park's circulating water system, reduce the amount of raw water used, save water resources, and thus maximize the utilization of resources.
[0035] (3) After the invention is put into production, at a rate of 260m 3 The black water meter, with a capacity of 245℃ and a flow rate of 1 / h, generates an average of about 1500 kWh of electricity per hour, which greatly reduces production costs and makes effective use of resources.
[0036] The working process of this invention is as follows: The gasified black water (220-250℃) from the gasifier 1 exchanges heat with the water in the buffer tank 5 through the first heat exchanger 2, and then enters the hydrocyclone separator 3 for separation. After separation, supernatant and black water are obtained. The mass ratio of supernatant to black water can reach 1:0.5-1. The separated supernatant goes to the washing tower 6 to clean the crude coal gas, and the separated black water goes to the first flash tank 4 for depressurized flash evaporation. The liquid phase after flash evaporation in the first flash tank 4 enters the clarifier 16 for clarification. The clarified liquid then flows into... The water replenishment tank 21 can replenish water for the system. After clarification, the material at the bottom of the clarification tank 16 passes through the filter press 17, and the filter cake enters the filter cake storage device 20. The filtrate is returned to the clarification tank 16 for recycling. The gas phase after flashing in the first flash tank 4 enters the second flash tank 27 after heat exchange in the second heat exchanger 26. The gas after flashing in the second flash tank 27 enters the flare tower 39 for combustion treatment. The liquid phase after depressurization flashing in the second flash tank 27 enters the coal slurry preparation device 36 through the condensate recovery tank 35.
[0037] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.
Claims
1. A coal-to-ammonia gasification black water comprehensive utilization device, characterized in that... The system includes a gasifier, a first heat exchanger, a hydrocyclone separator, a first flash tank, a buffer tank, and a scrubbing tower. The outlet of the gasifier and the tube-side inlet of the first heat exchanger are connected by a first pipeline; the tube-side outlet of the first heat exchanger and the inlet of the hydrocyclone separator are connected by a second pipeline; the supernatant outlet of the hydrocyclone separator and the inlet of the scrubbing tower are connected by a third pipeline; the black water outlet of the hydrocyclone separator and the inlet of the first flash tank are connected by a fourth pipeline; the outlet of the buffer tank and the shell-side inlet of the first heat exchanger are connected by a fifth pipeline; the shell-side outlet of the first heat exchanger and the return end of the buffer tank are connected by a sixth pipeline. A pump is installed on the fifth pipeline, a first turbine is installed on the sixth pipeline, and a first generator is connected to the outside of the first turbine.
2. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 1, characterized in that... The first flash tank has a clarification tank and a filter press on its outer side. The clarification tank has an inlet at the top and an outlet at the bottom. The outlet of the first flash tank and the inlet of the clarification tank are connected together by a seventh pipeline. The clarification tank has a discharge end at the bottom. The discharge end of the clarification tank and the inlet of the filter press are connected together by an eighth pipeline. A pump is installed on the eighth pipeline.
3. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 2, characterized in that... The outer side of the first flash tank has a filter cake storage device, a water replenishment tank, and a filtrate buffer tank. The filter press has a filter cake outlet and a filtrate outlet. The filter cake outlet of the filter press is connected to the feed end of the filter cake storage device. The filtrate outlet of the filter press and the inlet of the filtrate buffer tank are connected together through the ninth pipeline. The upper part of the clarifier has a return end. The outlet of the filtrate buffer tank and the return end of the clarifier are connected together through the tenth pipeline. A pump is installed on the tenth pipeline. The top of the clarifier has an overflow end. The overflow end of the clarifier and the inlet of the water replenishment tank are connected together through the eleventh pipeline.
4. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 1, 2, or 3, characterized in that... It also includes a second heat exchanger and a second flash tank. The top of the first flash tank is provided with an outlet. The outlet of the first flash tank and the tube-side inlet of the second heat exchanger are connected together by the twelfth pipeline. The tube-side outlet of the second heat exchanger and the liquid inlet of the second flash tank are connected together by the thirteenth pipeline. The fourteenth pipeline is connected between the fifth pipeline and the shell-side inlet of the second heat exchanger. The fifteenth pipeline is connected between the shell-side outlet of the second heat exchanger and the sixth pipeline. A second turbine is installed on the fifteenth pipeline. A second generator is connected to the outside of the second turbine.
5. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 4, characterized in that... The second flash tank has a condensate recovery tank and a coal slurry preparation device on its outside. The outlet of the second flash tank and the inlet of the condensate recovery tank are connected together by the sixteenth pipeline. The outlet of the condensate recovery tank and the inlet of the coal slurry preparation device are connected together by the seventeenth pipeline. A pump is installed on the seventeenth pipeline.
6. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 4, characterized in that... The second flash tank has a flare tower on its outside and an outlet at the top. The outlet of the second flash tank and the inlet of the flare tower are connected by an eighteenth pipeline, on which a pressure gauge and a valve are installed respectively; or / and, the first generator has a first power grid on its outside and the power output of the first generator is connected to the first power grid; or / and, the second generator has a second power grid on its outside and the power output of the second generator is connected to the second power grid.
7. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 5, characterized in that... The second flash tank has a flare tower on its outside and an outlet at the top. The outlet of the second flash tank and the inlet of the flare tower are connected by an eighteenth pipeline, on which a pressure gauge and a valve are installed respectively; or / and, the first generator has a first power grid on its outside and the power output of the first generator is connected to the first power grid; or / and, the second generator has a second power grid on its outside and the power output of the second generator is connected to the second power grid.
8. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 4, characterized in that... A thermometer is installed on the first pipeline, and flow meters are installed on the third, fourth, and twelfth pipelines, respectively.
9. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 7, characterized in that... A thermometer is installed on the first pipeline, and flow meters are installed on the third, fourth, and twelfth pipelines, respectively.
10. The coal-to-ammonia gasification black water comprehensive utilization device according to claim 7, characterized in that... Valves are installed on the first, second, third, fourth, fifth, sixth, seventh, eighth, tenth, eleventh, thirteenth, fourteenth, fifteenth, sixteenth and seventeenth pipelines respectively.