149 results about "Blackwater" patented technology

The invention relates to the technical field of coal chemical industry, in particular to a coal gasification black water circulation and black water waste heat recycling system and method. The coal gasification black water circulation and black water waste heat recycling system comprises a synthesis gas washing tower, a high-pressure flash tank, a low-pressure flash tank, a black water heat exchanger, a vacuum flash tank, a settling tank, a grey water tank, a low-pressure flash steam stripping tower and a high-pressure flash steam stripping tower. The coal gasification black water treated by the coal gasification black water circulating and black water waste heat recycling system can be reused as circulating water of a synthesis gas washing tower, so that the cyclic utilization of water resources is realized, the use of fresh water and the discharge of waste water are reduced, and the production cost and the environmental pressure are reduced. Meanwhile, the problem that a black water pipeline is scaled and blocked due to high temperature is solved, waste heat of the black water can be fully replaced for effective utilization, carbon is reduced, energy is saved, the purpose of cooling the black water is achieved, the cooling cost of a vacuum flash evaporation system is saved, and continuous and reliable economic benefits are created for enterprises.

The utility model discloses a black water waste heat high-quality recycling system which comprises a high-pressure purification flash evaporator, a low-pressure purification flash evaporator, a high-flash tank and a low-flash tank, black water is sequentially subjected to four times of flash evaporation stripping, flash steam generated by the high-pressure purification flash evaporator and flash steam generated by the low-pressure purification flash evaporator respectively act with an evaporator to generate saturated steam, and the saturated steam is separated from the low-flash tank. The saturated steam can meet different process applications after being pressurized by the steam pressurizing device; the high-flash condenser is used for condensing high-flash steam discharged by the high-flash tank, non-condensable gas enters a torch treatment pipeline, and condensed water is recycled in the process; the low flash tank is used for receiving the liquid part discharged by the high flash tank; the low-flash condenser is used for condensing low-flash steam in the low-flash tank and then returning the condensed low-flash steam to a process system for recycling; and the demineralized water preheater is used for receiving part of the low-flash liquid discharged by the low-flash tank to preheat the demineralized water. According to the utility model, the waste heat of black water can be extracted in a grading manner and efficiently utilized.

A fly ash prevention device for treating high-concentration water relates to the technical field of petrochemical engineering and comprises a flash evaporation concentration tower, a flash steam outlet is formed in the top of the flash evaporation concentration tower, and a black water outlet is formed in the bottom of the flash evaporation concentration tower; the tower wall of the flash concentration tower is connected with a black water connecting pipe, and black water tangentially enters the tower through the black water connecting pipe; a black water concentration chamber is arranged at the bottom in the flash evaporation concentration tower, the bottom of the black water concentration chamber is communicated with a black water outlet, an ascending pipe is arranged above the black water concentration chamber, a steam ascending cap is arranged on the ascending pipe, a fly ash prevention filler washing assembly is arranged above the steam ascending cap, and a gas distributor is arranged above the fly ash prevention filler washing assembly; a high-efficiency demister is arranged at the top in the flash evaporation concentration tower and is arranged on the flash steam outlet; according to the technical scheme, coal gasification and heavy oil gasification water systems are optimized, black water is concentrated, the washing environment is improved, and fly ash is prevented from being carried into a rear system.

The invention provides a black water waste heat recovery method and application, and belongs to the technical field of chemical engineering, the method is as follows: a black water pipeline from a gasification furnace is sequentially flashed through a high-pressure flash tank, a low-pressure flash tank and a vacuum flash tank and finally reaches a precipitation tank; a process pipeline is additionally arranged on the upstream of a black water pipeline adjusting valve at the bottom of a high-pressure flash tank, the process pipeline is connected to a shell pass of a high-pressure carbon dioxide heat exchanger in parallel and exchanges heat with a tube pass of the high-pressure carbon dioxide heat exchanger, the temperature is increased after heat exchange, and the process pipeline is sent to all users for use; after black water discharged from the high-pressure flash tank is subjected to heat exchange through the high-pressure CO2 heat exchanger, the temperature is reduced, the flow to the low-pressure flash tank is controlled by adjusting a downstream black water flow adjusting valve, the thermal load of the low-pressure flash tank is indirectly reduced, the flow to the vacuum flash tank is controlled by the low-pressure flash tank through a downstream black water adjusting valve, and the thermal load of the vacuum flash tank is reduced. And the vacuum pump of the vacuum flash is reduced or stopped according to the vacuum flash pressure condition, so that energy is saved. High-flash black water waste heat replaces low-pressure steam, and the true flash load is indirectly reduced.

The invention discloses a coal gasification black water multi-stage deep treatment device and method, and relates to the technical field of water treatment.The coal gasification black water multi-stage deep treatment device comprises a flash tank, a settling tank, a mixing and clarifying tank, a partition plate, an overflow opening, a mixing cavity, a clarifying and stirring mechanism, a pressing plate, a water inlet tank and a fixed bin, the two sides of the fixed bin are open, and an adjusting plate is clamped in the fixed bin and horizontally and freely slides in the fixed bin; a water storage space is defined by the adjusting plate, the fixed bin and the partition plate. According to the device, the pressing plate moves downwards, so that the pressing plate extrudes an extraction liquid in the mixing cavity, part of the extraction liquid enters the water storage space from the water inlet groove under the action of pressure, then along with downward movement of the pressing plate, the liquid level of the extraction liquid in the water storage space rises, and the extraction liquid flows into the clarifying cavity from the overflow port; after entering the water storage space, the extraction liquid loses the acting force of the stirring mechanism, so that a relatively large turbulence phenomenon is avoided, the extraction liquid can flow into the clarification cavity at a relatively low flow speed, and the clarification efficiency is prevented from being influenced.

The invention provides a resource recovery type black and grey water treatment system. The system comprises an oil separation device, a filtering device, a grey water treatment unit, a three-grid septic tank and an ecological percolation device, wherein the oil separation device comprises a kitchen grey water inlet, a grease outlet and an oil separation grey water outlet; the filtering device comprises a bathing and clothes washing grey water inlet, an impurity outlet and a filtered grey water outlet; the grey water treatment unit comprises a coagulative precipitation device, a filtering and decolorizing device, a UV disinfection device and a storage device; the coagulative precipitation device comprises an oil-separated grey water inlet, a filtered grey water inlet, a first water outlet and a second water outlet; the filtering and decoloring device comprises a water inlet and a filtered and decolored water outlet; the UV disinfection device comprises a filtered and decolored water inlet and a disinfected water outlet; the storage device comprises a disinfected water inlet and a water outlet; the three-grid septic tank comprises a first grid, a second grid and a third grid which are connected, the first grid comprises a toilet flushing black water inlet, and the third grid comprises a mixed water outlet; the ecological percolation device comprises a mixed water inlet and a harmless water outlet.

The utility model provides a coal gasification black water heat combination system which comprises a black water cooling unit and a heat recycling unit, the heat recycling unit comprises a first heat utilization part and a second heat utilization part, a bottom outlet of a high-pressure flash evaporator is connected with a black water inlet of a heat exchange unit, and a black water outlet of the heat exchange unit is connected with an inlet of a low-pressure flash evaporator. A bottom outlet of the low-pressure flash evaporator is connected with an inlet of the vacuum flash evaporator, a heating medium water outlet of the heat exchange unit is connected with an inlet of the heat using island, an outlet of the heat using island is connected with an inlet of the buffer tank, an outlet of the buffer tank is connected with an inlet of the circulating pump, and an outlet of the circulating pump is connected with a heating medium water inlet of the heat exchange unit. An inlet of the second heat utilization part is connected with a flash steam outlet of the high-pressure flash evaporator and a flash steam outlet of the low-pressure flash evaporator, black water heat at the bottom of the high-pressure flash evaporator is exchanged into heat medium water, the heat medium water obtained after heat exchange is used for a heat using island, and therefore the heat of the black water is comprehensively utilized.

The utility model relates to an experimental device for simulating black water scouring corrosion material, including frame table, frame table right side is equipped with the water storage tank of storing black water of experimental use, and the left side upper portion in water storage tank has the scouring test area, adjustable clamp is provided in the scouring test area, adjustable clamp includes the lifting frame, the first clamping plate and second clamping plate are equipped with on the lifting frame, when the first clamping plate is close or far from the second clamping plate and moves, the material sample used in the experiment is clamped or loosened, and the water spraying pipe that sprays black water to the material sample is installed on the left side surface of water storage tank. The utility model clamps the material sample on adjustable clamp, and the material sample is circulated and scoured and corroded through the water spraying pipe, to simulate the complex environment under the actual condition, accurately test the corrosion resistance of metal material after being scoured by black water for a long time, and the overall structure is simple, convenient operation.

The present application relates to the technical field of industrial chemistry, and discloses a gasifier black water recycling process. The process mainly solves the problems of high energy consumption, low heat exchange efficiency caused by fouling and insufficient utilization of waste heat in the direct treatment of low-flash black water from a gasifier. The process steps include: introducing the low-flash black water generated by the gasifier into a pretreatment unit, injecting a composite scale inhibitor into the unit, and mixing to form a homogeneous dispersion system; sending the pretreated black water into a black water heat exchanger for indirect heat exchange with closed-circulation desalted water, the heated desalted water enters an ORC low-temperature generator set, and energy conversion is completed through an organic working medium circulation system to realize the conversion of heat energy into electric energy; the composite scale inhibitor is prepared by copolymer solution synthesis, modified additive preparation, and compounding with sodium polyepoxysuccinic acid and modified sodium lignosulfonate. The present application effectively prevents fouling of the heat exchanger, significantly improves the heat exchange efficiency and the stability of the system operation, and realizes efficient recovery and resource utilization of the waste heat in the black water.

The utility model provides a high-solid-content black water treatment and energy recovery system, and belongs to the field of wastewater filtration. According to the utility model, the tubular automatic backwashing filter is used for filtering the black water in the gasification furnace, so that the blockage and abrasion of other equipment are reduced, the filtering efficiency is improved, the problem that the energy of the black water with overhigh solid content cannot be recycled is solved, the recycled electric energy can be reused, the energy is saved, the energy consumption is reduced, and the production cost is reduced. Filtered filtrate is introduced into the hydraulic turbine equipment, pressure energy of the filtrate is recycled, heat of the filtrate flowing out of the hydraulic turbine equipment is recycled again through the heat exchanger, cold fluid is heated by the recycled heat energy, and redundant energy consumption is saved.

The invention relates to the technical field of kitchen garbage treatment, and discloses a hermetia illucens breeding-based kitchen garbage degrading device which comprises a tank body, the sealing cover is arranged above the tank body; the hopper is arranged in the tank body; the crushing unit is arranged in the tank body and located below the hopper, and the crushing unit is used for crushing the fed kitchen garbage; the discharge valve is arranged below the tank body; the extraction mechanism is arranged on the tank body, and the slurry mixing mechanism comprises a rotating shaft rotationally arranged at the bottom in the tank body, a sleeve shaft fixedly connected to the surface of the rotating shaft, a plurality of groups of first stirring blades distributed on the peripheral edge of the sleeve shaft at equal intervals, and a reciprocating screw rod fixedly connected in the tank body. By arranging the slurry mixing mechanism and the adjusting mechanism, excessive liquid is actively separated, slurry is dynamically extruded, the efficiency of extracting the excessive liquid by the extraction pump is effectively improved, and the ingestion and conversion effects of hermetia illucens larvae on organic components are further improved by controlling the water content of the slurry to be proper.

The utility model relates to the technical field of coal chemical industry, in particular to a coal gasification black water circulation and black water waste heat recycling system. The coal gasification black water circulation and black water waste heat recycling system comprises a synthesis gas washing tower, a high-pressure flash tank, a low-pressure flash tank, a black water heat exchanger, a vacuum flash tank, a settling tank, a grey water tank, a low-pressure flash steam stripping tower and a high-pressure flash steam stripping tower. The coal gasification black water treated by the coal gasification black water circulation and black water waste heat recycling system disclosed by the utility model can be recycled as circulating water of a synthesis gas washing tower, so that the cyclic utilization of water resources is realized, the use of fresh water and the discharge of waste water are reduced, and the production cost and the environmental pressure are reduced. Meanwhile, the problem that a black water pipeline is scaled and blocked due to high temperature is solved, waste heat of the black water can be fully replaced for effective utilization, carbon is reduced, energy is saved, the purpose of cooling the black water is achieved, the cooling cost of a vacuum flash evaporation system is saved, and continuous and reliable economic benefits are created for enterprises.

The invention discloses a system and method for heating desalted water by using waste heat of a black water gasification process, and belongs to the technical field of coal chemical industry energy conservation, and the system is additionally provided with a black water heat exchanger, a desalted water heat exchanger, a boiler water buffer tank and a circulating pump on an original net pipe. According to the method, a closed circulation loop with boiler water as an intermediate heating medium is constructed, high-temperature black water from a gasification furnace is subjected to indirect heat exchange with the boiler water in a black water heat exchanger, and waste heat is recycled; the heated boiler water is buffered and pumped and then indirectly exchanges heat with desalted water to be heated in the desalted water heat exchanger, so that the desalted water is heated to the required temperature and then fed into a boiler deaerator. According to the invention, direct replacement of desalted water heating steam by black water waste heat is safely and reliably realized, meanwhile, the black water cooling load is reduced, and remarkable energy-saving and consumption-reducing effects and economic benefits are achieved; clean boiler water is adopted as an intermediate heating medium, so that the risks of blockage, corrosion and cross contamination possibly caused by direct heat exchange are avoided.

The present application provides a coal gasification black water treatment device system and method, which adopts two-stage vortex separation devices for heat recovery and solid-liquid separation, wherein the secondary vortex separation device improves the solid-liquid separation effect by adding a specific composite medicament, and the treated grey water meets the requirements of the subsequent biochemical treatment; the coal gasification black water treatment device system cancels the high-pressure flash evaporation device, low-pressure flash evaporation device, deoxygenation device and sedimentation device required to be arranged in the traditional coal gasification black water treatment device system, and solves the problems of complex existing process flow, large equipment occupation area and low heat utilization rate.

A environmentally sustainable system for toilet flushing and blackwater disposal is described; a respective method of toilet flushing and blackwater disposal by a mechanical system is further described; the system comprises: a toilet bowl, a bowl valve, a pumping mechanism, a check valve, a driving shaft, a gearing mechanism; the method comprises: collecting a blackwater, moving a sealing element, engaging the sealing element, disposing the sealing element, pumping the blackwater, conducting a flow of the blackwater, operationally connecting a driving shaft, operationally connecting in a predefined gearing ratio of operation the pumping mechanism with the bowl valve and with the driving shaft.

The invention provides a preparation method and device of green fuel, and the preparation method of the green fuel comprises the following steps: 1) carrying out gasification treatment on biomass to obtain a gas mixture; 2) washing the gas mixture to obtain crude synthesis gas and black water; (3) sequentially carrying out water-gas conversion treatment and purification treatment on the crude synthesis gas to obtain purified synthesis gas; 4) performing grey water treatment on the black water to obtain salt-containing wastewater and grey water; the preparation method of the green fuel comprises the following steps of (1) preparing salt-containing wastewater, (2) purifying the salt-containing wastewater, (3) pre-treating the salt-containing wastewater, and carrying out electrolytic treatment to obtain electrolytic wastewater and hydrogen, and (4) mixing the purified synthesis gas with the hydrogen, and carrying out a synthesis reaction to obtain the green fuel. The preparation method of the green fuel can reduce the discharge amount of the high-salt-content wastewater and reduce the consumption of water resources.

The utility model discloses a rapid classification resourceful treatment system, and relates to the technical field of sewage treatment. The device comprises a black water collecting pool and a grey water collecting pool which serve as user sides and are buried underground, the black water collecting pool is communicated with a black water pumping pipe, the grey water collecting pool is communicated with a grey water pumping pipe, the liquid outlet end of the water pumping pipe extends out of the ground and is provided with a quick connection device, the liquid outlet end of the water pumping pipe is arranged in a protection box, and the protection box is arranged on the ground. Electronic liquid level meters are respectively arranged in the black water collecting pool and the grey water collecting pool, and a positioning system is arranged in the protection box; the quick connection device comprises a first connector arranged on the black water pumping pipe or the grey water pumping pipe and a second connector arranged on a sewage pumping pipe of the sewage pumping truck. The signal output ends of the electronic liquid level instrument and the positioning system are communicated with the signal input end of the central control equipment; the purposes of improving the working efficiency of a sewage suction operation and maintenance team, reducing the sewage treatment difficulty and reducing the operation and maintenance cost are achieved.

The present invention relates to the technical field of domestic sewage treatment, and specifically discloses a small watershed rural domestic sewage treatment system and method. The method is to separately collect and treat black water and grey water in the farmer's courtyard, and through ditch transformation, utilization of the ecological treatment module system and the natural ecological system, sewage purification is realized. The system treats rural domestic sewage by combining the grey water treatment device with the ecological treatment module system, can overcome the disadvantages of high infrastructure cost, large floor area, complex management, high operation cost, poor ecology, etc., and obtains the tail water that can be directly utilized, truly realizing sewage purification, recycling, and turning waste into treasure.

The invention relates to the technical field of water treatment, in particular to a sewage separation and collection method and system based on a negative pressure source. Comprising a sewage source separation module, a negative pressure collection network, a multistage processing module, an intelligent control center, a safety monitoring module, an energy management module, a management module, a login module, an authority control module, an encryption transmission module, a block chain storage module and a prediction maintenance alarm module. The multi-stage treatment module comprises a black water advanced treatment unit, a grey water ecological treatment unit, a water quality improvement unit and a resource utilization unit; the negative pressure collection network is connected with the sewage source separation module, the multi-stage treatment module is connected with the negative pressure collection network, and the technical problems that in the prior art, when comprehensive intelligent management is achieved, operation and maintenance mostly depend on regular overhaul and post-event treatment, and accurate prediction and active maintenance of the system state are difficult to achieve are solved.

The invention belongs to the technical field of sewage treatment, particularly relates to river black and odorous water treatment equipment and a river black and odorous water treatment method, and provides the following scheme aiming at the problem of non-uniform dissolved oxygen caused by incapability of synchronously aerating and stirring black water by the existing black water treatment equipment: the river black and odorous water treatment equipment comprises a rack; the number of the floating blocks is two, the two floating blocks are fixedly connected to the rack and are symmetrically distributed with the transverse central axis of the rack as the center point, and the treatment equipment body is fixedly connected to the interior of the rack; the first filtering device is arranged on the left side of the treatment equipment body and used for intercepting large floating objects; the cleaning device is arranged on the rear side of the first filtering device and is used for cleaning the first filtering device; according to the invention, aeration and stirring work can be synchronously carried out on black water, so that the purpose of improving the uniformity of dissolved oxygen is achieved.

The invention relates to the technical field of environmental protection equipment, and discloses a kitchen waste gas treatment device based on hermetia illucens conversion, which comprises a negative pressure cultivation chamber, a spray tower arranged on the outer side of the negative pressure cultivation chamber, a water tank arranged at the bottom of the spray tower, a spray head arranged at the top of the spray tower, and a gas filtering mechanism arranged at the top of the spray tower, the disassembling mechanism is arranged in the middle of the air filtering mechanism and used for replacing the filtering part. By arranging the gas filtering mechanism, the filter plates can be switched during operation without shutdown, the process of converting hermetia illucens into kitchen garbage is not interrupted, the continuity of waste gas treatment is ensured, and the layout of the gas filtering mechanism ensures that the air outlet area is not influenced, which means that waste gas can smoothly pass through even when the filter plates are switched; the treatment efficiency cannot be reduced due to the adjustment of equipment, the maintenance of the air outlet area is crucial to the stable operation of the whole system, and the effective treatment and emission of waste gas are ensured.

A urinal attachment for a toilet comprises a receptacle defining an interior cavity and a front aperture for receiving urine, a cover removably attached to the receptacle and configured to form a fluid-tight seal over the front aperture, and a base for supporting the receptacle in an upright orientation. An articulated connecting bar assembly is hingedly coupled between a rear wall of the receptacle and a hinged connection of the toilet, enabling movement between a stored position and first and second operable positions of differing height. A water dispensing system includes a flexible conduit and a faucet assembly integrated into the cover, and is configured to dispense pressurized water into the cavity for cleaning when the cover is closed. A blackwater discharge system includes a flexible conduit connected to a lower wall opening and configured to convey waste to the toilet bowl. The connecting bar assembly may be length-adjustable or telescopic to accommodate variable toilet geometries.

Provided herein are filtration systems for treating wastewater (e.g, grey water and / or blackwater). The wastewater filtration system can include, one or more inlet pipes, a first container comprising one or more vermifilters, a second container comprising one or more vermifilters and one or more plant species, a filter system and / or one or more outlet pipes. More particularly, the wastewater filtration system provided herein includes a macro-organism and / or microorganisms for primary and secondary treatment of wastewater. In some embodiments, the macro-organism comprises Eisenia fetida. In some embodiments, the macro- organism comprises a plant species. In some embodiments, the microorganism comprises a bacteria species.

The utility model discloses a sewage tank device for a small pleasure boat. The sewage tank device comprises a tank body (1) and an integrated tank cover (2), and the integrated tank cover covers the tank body; a dirt containing pipe orifice (3), an exhaust pipe orifice (4) and a liquid level detector (5) are integrated on the integrated tank cover; the sewage containing pipe opening is communicated with a sewage discharging pipe opening of a sewage system so as to receive sewage discharged by the sewage system and enable the sewage to enter the tank body; the exhaust pipe opening is communicated with the atmosphere; the detection end of the liquid level detector extends into the tank body, and a detection signal of the liquid level detector is accessed into the alarm system; the sewage tank device is further provided with a plurality of standby tank bodies. According to the conception of the utility model, the sewage tank device is adopted to replace a black water cabin in the prior art to receive and collect black water, so that some defects of the design of the existing black water cabin are overcome, and particularly, the sewage tank device occupies a small space and does not need a complicated ship body design, so that the space of the ship body is saved.

The utility model discloses an anti-coking, impact-resistant and vibration-resistant adjusting ball valve for coal chemical industry black water, and relates to the field of adjusting ball valves. In coal chemical industry black water treatment, a black water medium has the characteristics of high suspended matter content, high temperature, high alkali content, high corrosion content and high-hardness solid particle content, and abrasion, corrosion, coking jamming and driving failure of traditional valve internals are easily caused. Comprising a fixing shaft, a left valve body, a right valve body, a left valve seat, a right valve seat, a ball body, a valve rod and an executing mechanism, the ball body, the valve seats and valve body flow channels are spray-welded with tungsten carbide layers with the hardness larger than or equal to HRC65, the left valve seat and the right valve seat achieve two-way pre-tightening sealing through spiral springs and the ball body, and scraper type cutting edges are arranged on the sealing faces of the valve seats. The valve rod adopts a large-diameter high-strength design and is in anti-rotation connection with the ball body, and the stuffing box adopts a disc spring load limiting and pressurizing structure. The wear resistance, impact resistance and coking resistance are remarkably improved, bidirectional reliable sealing is achieved, stable driving under the high-torque working condition is guaranteed, the service life of the valve is prolonged, and the valve is suitable for the coal chemical industry black water extreme working condition.

The invention relates to the technical field of coal gasification and oil gasification black water systems, and discloses a black water flash evaporation waste heat recovery system and method.The waste heat recovery system comprises a high-pressure evaporation hot water tower, a low-pressure evaporation hot water tower arranged on the downstream portion of the high-pressure evaporation hot water tower and a vacuum flash evaporator arranged on the downstream portion of the low-pressure evaporation hot water tower, a first-stage flash steam outlet positioned at the top end of the high-pressure evaporation hot water tower is directly connected with a second lower tower positioned at the bottom of the low-pressure evaporation hot water tower so as to increase the temperature of circulating grey water in the high-pressure evaporation hot water tower and the low-pressure evaporation hot water tower; and a first-stage black water outlet positioned at the bottom end of the high-pressure evaporation hot water tower is communicated with a second lower tower positioned at the bottom of the low-pressure evaporation hot water tower. According to the scheme, the heat of the flash steam is better utilized, a black water flash evaporation waste heat recovery system is further optimized, meanwhile, the flash steam subjected to high-pressure flash evaporation does not need to be cooled and subjected to liquid separation through a water cooler and a liquid separation tank, and the equipment cost is greatly reduced.

1. Name of the Design Product: Angle Valve (Square Body). 2. Use of the Design Product: A regulating valve for coal slurry or black water medium in coal slurry gasification projects. 3. Design Key Points of the Design Product: Lies in the shape. 4. Picture or Photograph that Best Illustrates the Design Key Points: Perspective View 1.

The invention discloses a black water treatment system of a pulverized coal gasification device, which comprises a high-pressure flash tank capable of receiving high-temperature black water generated by a gasification furnace and releasing part of steam and dissolved gas through reduced-pressure flash; the low-pressure flash tank is connected with the high-pressure flash tank and is used for receiving the black water discharged by the high-pressure flash tank and further performing flash cooling on the black water; the S-shaped vortex runner plate heat exchanger is connected with a black water pipeline at the outlet of the low-pressure flash tank, an S-shaped vortex runner is arranged in the S-shaped vortex runner plate heat exchanger, and the S-shaped vortex runner plate heat exchanger is provided with a black water side channel and a desalted water side channel; and the settling tank is connected with an outlet of a black water side channel of the S vortex runner plate heat exchanger so as to receive the black water which is cooled to about 70 DEG C through heat exchange, perform solid-liquid separation and convey normal-temperature desalted water to a desalted water side channel of the S vortex runner plate heat exchanger through a pipeline.

The invention discloses a method for preparing a liquid fertilizer by intermittent aerobic multi-stage circulating fermentation of black water, which comprises the following steps of: 1, introducing the collected black water into an adjusting tank, uniformly stirring the black water by using a stirring mechanism in the adjusting tank, introducing the black water into a grating tank, and removing large-particle impurities in the black water; after impurity removal, introducing the black water into a first sedimentation tank to naturally settle part of solid substances in the black water; 2, the black water settled in the step 1 is introduced into a multi-stage fermentation unit for multi-stage circulating fermentation, intermittent aeration is adopted in each stage of fermentation, and the oxygen aeration rate is gradually increased along with the fermentation depth; the staying time of each stage of fermentation of the fermentation liquor is sequentially shortened along with the fermentation depth; and 3, naturally settling the fermented liquid, wherein the supernatant is the liquid fertilizer. The traditional black water and manure solid fermentation mode is changed, the pretreated black water is subjected to multi-stage aerobic circulating fermentation treatment, the black water is converted into valuable liquid fertilizer, and harmless treatment and resourceful treatment of the black water are achieved.