A mixed salt wastewater resource regeneration treatment device and treatment method

Abstract

The invention discloses a mixed salt wastewater resource regeneration treatment device and method, including a thin film flash evaporator and a 2-stage or more evaporation crystallization vortex separator; the mixed salt wastewater is input into the thin film flash evaporator for flash evaporation and concentration, the concentrated liquid is sent from the bottom end thereof to the first stage evaporation crystallization vortex separator, evaporates and crystallizes the same salt product under the initiation of a salt seed, the cyclone light phase layer mixed salt wastewater is sent to the next stage evaporation crystallization vortex separator, evaporates and crystallizes another salt product under the initiation of another salt seed, and the cyclone light phase layer mixed salt wastewater is used in the next stage evaporation crystallization vortex separator, and the last stage cyclone light phase layer mixed salt wastewater is returned to the first stage evaporation crystallization vortex separator until the mixed salt wastewater is evaporated into industrial reuse water to obtain a pure salt product. The invention is safe and reliable, has low equipment manufacturing cost, low operating energy consumption, high wastewater treatment efficiency, strong continuity, and energy saving and emission reduction through the structural design of the thin film flash evaporator and the evaporation crystallization vortex separator and the equipment layout design.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a mixed salt wastewater resource regeneration treatment device and a treatment method. Background Art

[0002] The IT electronic chip industry, biopharmaceutical industry, organic pesticide industry and chemical industry all produce mixed salt wastewater. Mixed salt wastewater is very harmful to the ecological environment, which is a major problem in ecological environment protection and a major issue in today's waste management and comprehensive utilization of circular economy.

[0003] At present, the industry generally uses triple-effect evaporation crystallization facilities and NVR evaporation crystallization facilities to treat mixed salt wastewater. The resulting crystals are mixed salt solids. In order to avoid secondary pollution of the environment by the mixed salt solids, the mixed salt solids are then subjected to high-temperature decomposition, such as the gaseous synthesis of ammonium chloride process technology.

[0004] However, the above treatment methods have the following problems: 1. The production of triple-effect evaporation crystallization or NVR evaporation crystallization equipment requires many consumables, high cost, low thermal efficiency, high steam energy consumption, and low waste resource rate, resulting in high cost for mixed salt wastewater treatment; 2. The process of high-temperature decomposition of mixed salt solids has great safety risks, high energy consumption, special equipment materials, and large investment, which is not worth the cost. Summary of the invention

[0005] The present invention provides a mixed salt wastewater resource regeneration treatment device and a treatment method, which can solve the problems of high equipment investment cost, high energy consumption, low treatment efficiency, poor process safety, etc. existing in the existing mixed wastewater treatment.

[0006] In order to solve the above technical problems, the present invention provides a mixed salt wastewater resource regeneration treatment device, comprising: a thin film flash evaporator and an N-stage evaporation crystallization vortex separator, where N is an integer greater than or equal to 2;

[0007] The thin film flash evaporator includes a flash separation chamber and a liquid storage tank from top to bottom; a mixed salt wastewater distribution component is installed in the internal cavity of the flash separation chamber, and the mixed salt wastewater storage tank is connected to the mixed salt wastewater distribution component through a pipeline; the bottom end of the liquid storage tank is connected to the liquid inlet of the N-stage evaporation crystallization vortex separator in sequence through a concentrated brine discharge pipe;

[0008] Each level of the evaporation and crystallization vortex separator includes a gas-liquid separation chamber, a vortex separation chamber and a heating cyclone chamber from top to bottom; the shells of the vortex separation chamber and the heating cyclone chamber are respectively provided with a tangent input port and a tangent output port; the tangent input port and the tangent output port are respectively connected to the outlet and the inlet of the forced circulation pump; the pipeline between the tangent input port and the outlet of the forced circulation pump is also connected to a cyclone light phase layer mixed salt wastewater outlet pipe; in the N-level evaporation and crystallization vortex separators, the cyclone light phase layer mixed salt wastewater outlet pipe of the previous stage evaporation and crystallization vortex separator is connected to the liquid inlet of the next stage evaporation and crystallization vortex separator, and the cyclone light phase layer mixed salt wastewater outlet pipe of the last stage evaporation and crystallization vortex separator is connected to the liquid inlet of the first stage evaporation and crystallization vortex separator;

[0009] The bottom of each stage of the evaporation crystallization vortex separator is provided with a crystallization material outlet, which is connected to a filter dryer through a pipeline;

[0010] Salt seeds consistent with the salt product to be evaporated and crystallized are placed in each stage of the evaporation and crystallization vortex separator.

[0011] In a preferred embodiment of the present invention, a heater is installed in the internal cavity of the flash separation chamber and the heating cyclone chamber, and the heater includes a steam input pipe, a steam output pipe, a plurality of groups of small circular heating coils and a plurality of groups of large circular heating coils;

[0012] The top end port of the steam input pipe is connected to the fresh steam pipe or the secondary steam vacuum pipe, and the bottom end port thereof is closed;

[0013] The top end port of the steam output pipe is closed, and the bottom end port thereof is connected to a secondary steam vacuum pipe or a steam water collecting tank;

[0014] The multiple groups of large circular heating coils are wound on the steam input pipe and the steam output pipe from top to bottom, the steam input port of each group of the large circular heating coils is connected to the steam input pipe, and the steam output port of each group of the large circular heating coils is connected to the steam output pipe; and the steam input port of the same group of large circular heating coils is at the top, and the steam output port is at the bottom;

[0015] Multiple groups of small circular heating coils are arranged from top to bottom between the steam input pipe and the steam output pipe, the steam input port of each group of small circular heating coils is connected to the steam input pipe, and the steam output port of each group of small circular heating coils is connected to the steam output pipe; and the steam input port of the same group of small circular heating coils is at the top, and the steam output port is at the bottom.

[0016] In a preferred embodiment of the present invention, the mixed salt wastewater distribution component is located in the internal cavity of the flash separation chamber of the thin film flash evaporator; the mixed salt wastewater distribution component includes a mixed salt wastewater distribution disc, a mixed salt wastewater input pipe, a mixed salt wastewater spray delivery pipe and a plurality of spray film forming pipes;

[0017] The mixed salt wastewater distribution disc is installed in the upper middle part of the heater, the center of its upper surface is connected to the mixed salt wastewater input pipe, the center of its lower surface is connected to the mixed salt wastewater spray delivery pipe, and a plurality of spray liquid distribution ports are arranged around its side, and the spray liquid distribution ports are connected to the spray film forming pipe;

[0018] The spray film-forming tube is installed in the area between the large circular heating coil and the small circular heating coil, with its top end connected to the mixed salt wastewater distribution disc and its bottom end closed; each of the spray film-forming tubes is provided with micropores.

[0019] In a preferred embodiment of the present invention, the micropores are located on the wall of the spray film-forming tube corresponding to the gap between the upper coil and the lower coil of the large circular heating coil and on the wall of the spray film-forming tube corresponding to the gap between the upper coil and the lower coil of the small circular heating coil.

[0020] In a preferred embodiment of the present invention, a spray pump is installed on the concentrated brine discharge pipe, the outlet pipe of the spray pump is connected to the bottom end of the mixed salt wastewater spray delivery pipe, and its outlet branch pipe is connected to the liquid inlet of the next stage evaporation crystallization vortex separator.

[0021] In a preferred embodiment of the present invention, a vortex deflector is also installed in the heating vortex chamber of the evaporation crystallization vortex separator, and the vortex deflector includes a funnel and a guide tube; the large-diameter end of the funnel is connected to the top of the heating vortex chamber, and the small-diameter end is connected to the top end of the guide tube, and the bottom of the guide tube is suspended above the bottom of the heating vortex chamber.

[0022] In a preferred embodiment of the present invention, a semicircular steam coil is wound on the outer wall of the cylinder of the heating vortex chamber, the inlet end of the semicircular steam coil is connected to the fresh steam pipe, and the outlet end is connected to the steam water collection tank.

[0023] In a preferred embodiment of the present invention, the liquid inlet of the evaporation crystallization vortex separator is located on the middle cylinder wall of the vortex separation chamber, and a first magnetic flow promoter is installed on the cylinder wall of the vortex separation chamber on the opposite side of the liquid inlet; the second magnetic flow promoter is installed on the bottom of the cylinder wall of the heating vortex chamber on the same side of the liquid inlet.

[0024] In a preferred embodiment of the present invention, the mixed salt wastewater storage tank is connected to the mixed salt wastewater input pipe in the mixed salt wastewater distribution assembly through a pipeline, and a preheater is also installed on the pipeline between the mixed salt wastewater storage tank and the mixed salt wastewater input pipe.

[0025] In order to solve the above technical problems, the present invention also provides a mixed salt wastewater resource regeneration treatment method, which is carried out in the above treatment device and includes the following steps:

[0026] (1) Adding salt seeds: Add appropriate amount of salt seeds of the same type as the evaporation and crystallization salt products into each level of evaporation and crystallization vortex separator;

[0027] (2) Flash concentration: The mixed salt wastewater is transported to the mixed salt wastewater distribution disk of the thin film flash evaporator, flows out through the micropores on the spray film tube, and is collected in the liquid storage bin;

[0028] Under the action of the spray pump, the mixed salt wastewater in the liquid storage bin is returned to the mixed salt wastewater distribution disc through the mixed salt wastewater spray delivery pipe, and then sprayed onto the inner wall of the thin film flash evaporator and the outer wall of the flash heater through the spray film forming pipe to form a water film layer, and thin film flash evaporation is performed. The gas after flash evaporation is discharged from the top of the thin film flash evaporator for reuse, and the liquid is concentrated into mixed salt wastewater with a total salt concentration close to saturation. Part of the mixed salt wastewater with a total salt concentration close to saturation is transported to the first-stage evaporation crystallization vortex separator through the outlet branch pipeline;

[0029] (3) Evaporation and crystallization of the first salt product: the mixed salt wastewater with a total salt concentration close to saturation entering the first-stage evaporation and crystallization vortex separator continues to evaporate under the action of the heater, and the first salt product is crystallized under the initiation of the first salt seed crystal. The heavy phase mixed salt wastewater containing the crystallized salt swirls and sinks, and is discharged through the crystallization material outlet, and the first salt is dried and recovered; the light phase mixed salt wastewater swirls in the vortex separation chamber under the action of the forced circulation pump, and at the same time, part of the light phase mixed salt wastewater flows into the next stage evaporation and crystallization vortex separator through the swirl light phase layer mixed salt wastewater outlet pipe for application;

[0030] (4) Evaporation and crystallization of the Nth salt product: The mixed salt wastewater entering the Nth stage evaporation and crystallization vortex separator repeats the process in step (3) to obtain the Nth salt product, and the light phase mixed salt wastewater then flows into the first stage evaporation and crystallization vortex separator through the cyclone light phase layer mixed salt wastewater outlet pipe for application, and the evaporation and crystallization are circulated in this way until the mixed salt wastewater is evaporated into industrial water.

[0031] The beneficial effects of the present invention are as follows: the present invention provides a mixed salt wastewater resource regeneration treatment device and treatment method. The device adopts the structural design of a thin film flash evaporator and a multi-stage evaporation crystallization vortex separator with salt seeds pre-introduced. The process flow for classifying and recovering salt products is simple, safe and reliable. The equipment has low manufacturing cost, low operating energy consumption, high mixed salt wastewater treatment efficiency, strong continuity, easy operation, energy saving and emission reduction effects, and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a three-dimensional structural schematic diagram of a preferred embodiment 1 of a mixed salt wastewater resource regeneration treatment device of the present invention;

[0033] Figure 2 is a schematic diagram of the internal structure of the thin film flash evaporator shown;

[0034] Figure 3 Schematic diagram of the internal structure of the evaporation crystallization vortex separator shown;

[0035] The markings of the components in the accompanying drawings are as follows:

[0036] 100. First stage evaporation crystallization vortex separator;

[0037] 200. Second stage evaporation crystallization vortex separator;

[0038] 300. The third stage evaporation crystallization vortex separator;

[0039] 400. Thin film flash evaporator, 410. Flash separation chamber, 420. Liquid storage tank, 411. First steam input pipe, 412. First steam output pipe, 413. First small circular heating coil, 414. First large circular heating coil, 415. Mixed salt wastewater distribution disc, 416. Spray film forming pipe, 417. Mixed salt wastewater spray delivery pipe, 418. Umbrella demister, 419. Mixed salt wastewater input pipe, 421. Concentrated brine discharge pipe, 422. Spray pump,

[0040] 500. Secondary steam vacuum tube; 600. Preheater;

[0041] 700. forced circulation pump, 710. cyclone light phase mixed salt wastewater outlet pipe;

[0042] 810. Funnel, 820. Diversion tube;

[0043] 910. second steam input pipe, 920. second steam output pipe, 930. second small circular heating coil, 940. second large circular heating coil, 950. semicircular steam coil, 960. first magnetic flow pusher, 970. second magnetic flow pusher;

[0044] 1000. Heat exchanger; 1100. Hot filter dryer; 1200. Water ring vacuum pump; 1300. Cooling tower, 1400. Mixed salt wastewater storage tank;

[0045] Ⅰ. Gas-liquid separation chamber, Ⅱ. Vortex separation chamber, Ⅲ. Heating cyclone chamber. DETAILED DESCRIPTION

[0046] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0047] See also Figure 1-3 , the embodiment of the present invention includes:

[0048] The invention discloses a mixed salt wastewater resource regeneration treatment device and treatment method, the treatment device comprises a thin film flash evaporator and N-stage evaporation crystallization vortex separators, N is an integer greater than or equal to 2; each stage of the evaporation crystallization vortex separators carries salt crystal seeds of the same type as the salt product to be evaporated and crystallized. The invention is applicable to mixed salt wastewater with a total salt concentration of <20%.

[0049] Preferably, the mixed salt wastewater is first preheated by a preheater, and then passed into a thin film flash evaporator for flash evaporation to be concentrated into a mixed salt wastewater with a total salt concentration close to a saturated solution state, and then passed into each level of evaporation crystallization vortex separator step by step for evaporation and crystallization to obtain various types of salt products of the same type as the salt crystal seeds in each level of evaporation crystallization vortex separator. The mixed salt wastewater after the salt is separated and crystallized by the previous level evaporation crystallization vortex separator is used in the next level evaporation crystallization vortex separator until the mixed salt wastewater is evaporated into industrial water and the salt in the mixed salt wastewater is crystallized into clean salt products, thereby achieving effective separation and recovery of various salts in the mixed salt wastewater and realizing the recycling of resources. Among them, the number of stages of the evaporation crystallization vortex separator is determined by the type of salt in the mixed salt wastewater.

[0050] Taking mixed salt wastewater containing three salt components, sodium sulfate, sodium chloride and ammonium chloride, as an example, the technical scheme of the mixed salt wastewater resource regeneration treatment device and treatment method of the present invention is described in detail below. Example 1

[0051] A mixed salt wastewater resource regeneration treatment device is used to treat mixed salt wastewater with a total salt concentration of less than 20% and containing three salts: sodium sulfate, sodium chloride and ammonium chloride.

[0052] Specifically, the processing device includes: a first-stage evaporation crystallization vortex separator 100 , a second-stage evaporation crystallization vortex separator 200 , a third-stage evaporation crystallization vortex separator 300 and a thin film flash evaporator 400 .

[0053] The thin film flash evaporator 400 includes a flash separation chamber 410 and a liquid storage tank 420 in order from top to bottom.

[0054] The flash separation chamber 410 is a cylindrical barrel structure, with a secondary steam outlet on the top thereof and connected to a secondary steam vacuum pipe 500 . The secondary steam vacuum pipe 500 is connected to the evaporation heater of the third-stage evaporation crystallization vortex separator 300 .

[0055] The liquid storage bin 420 is a conical structure, and a concentrated brine discharge pipe 421 is connected to the bottom thereof. A spray pump 422 is installed on the concentrated brine discharge pipe 421, and the spray pump 422 has an outlet pipe and an outlet branch pipe. The outlet pipe is connected to the bottom of the flash separation chamber 410; and the outlet branch pipe is connected to the liquid inlet of the first-stage evaporation crystallization vortex separator 100.

[0056] A steam coil is installed on the inner wall surface of the flash separation chamber 410, and a mixed salt wastewater distribution component and a flash heater are installed in the internal cavity thereof.

[0057] The flash heater includes a first steam input pipe 411 , a first steam output pipe 412 , a plurality of first small circular heating coils 413 and a plurality of first large circular heating coils 414 .

[0058] The bottom end of the first steam input pipe 411 is a closed end, and the top end is connected to the second-stage evaporation crystallization vortex separator 200 through the secondary steam vacuum pipe 500 .

[0059] The top end port of the first steam output pipe 412 is a closed end, and the bottom end port thereof is connected to the evaporation heater of the third-stage evaporation crystallization vortex separator 300 through the secondary steam vacuum pipe 500 .

[0060] The multiple groups of first small circular heating coils 413 are arranged from top to bottom between the first steam input pipe 411 and the first steam output pipe 412, and the steam input port of each group of first small circular heating coils 413 is connected to the first steam input pipe 411, and the steam output port thereof is connected to the first steam output pipe 412. The longitudinal heights of the groups of first small circular heating coils 413 are the same.

[0061] The multiple groups of first large circular heating coils 414 are placed or wrapped around the first steam input pipe 411 and the first steam output pipe 412 from top to bottom, and the steam input port of each group of first large circular heating coils 414 is connected to the first steam input pipe 411, and its steam output port is connected to the first steam output pipe 412.

[0062] The sum of the cross-sectional areas of the multiple groups of first small circular heating coils 413 and the multiple groups of first large circular heating coils 414 is equal to the cross-sectional area of ​​the first steam input pipe 411, ensuring that the steam from the first steam input pipe 411 is evenly distributed in each circular heating coil, avoiding short circuits and ensuring smooth input and discharge of hot steam.

[0063] The flash heater composed of the first steam input pipe 411, the first steam output pipe 412, the plurality of first small circular heating coils 413 and the plurality of first large circular heating coils 414 is arranged in the inner cavity of the thin film flash evaporator, without using a shell layer, thus saving the cost of shell consumables. In addition, the tube walls of the first steam input pipe 411, the first steam output pipe 412, the plurality of first small circular heating coils 413 and the plurality of first large circular heating coils 414 can form a water film layer, and the surface area of ​​the tube wall constitutes the water film layer area of ​​the thin film flash evaporator, which is conducive to increasing the water film layer area and improving the flash evaporation efficiency and flash evaporation effect.

[0064] The mixed salt wastewater distribution component includes a mixed salt wastewater distribution disc 415, a mixed salt wastewater input pipe 419, a plurality of spray film-forming pipes 416 and a mixed salt wastewater spray delivery pipe 417.

[0065] The mixed salt wastewater distribution disc 415 is horizontally arranged and installed in the upper middle part of the flash heater, the center of its upper surface is connected to the mixed salt wastewater input pipe 419, and the center of its lower surface is connected to the mixed salt wastewater spray delivery pipe 417. A plurality of spray liquid distribution ports are opened around its side, and are connected to the spray film-making pipe 416 through the spray liquid distribution ports.

[0066] The mixed salt wastewater input pipe 419 is connected to the mixed salt wastewater storage tank 1400 through a pipe. Preferably, a preheater 600 is also installed on the pipe between the mixed salt wastewater input pipe 419 and the mixed salt wastewater storage tank 1400. The mixed salt wastewater preheated by the preheater 600 enters the thin film flash evaporator 400, which can improve the flash evaporation efficiency.

[0067] A plurality of the spray film-forming tubes 416 are vertically installed in the area between the first large circular heating coil 414 and the first small circular heating coil 413, with the top end connected to the mixed salt wastewater distribution disc 415 and the bottom end closed; each of the spray film-forming tubes 416 is provided with micro-holes in a directional and quantitative manner. Specifically, the micro-holes are located on the wall of the spray film-forming tube 416 corresponding to the gap between the upper coil and the lower coil of the first large circular heating coil and on the wall of the spray film-forming tube 416 corresponding to the gap between the upper coil and the lower coil of the first small circular heating coil 413.

[0068] The sum of the areas of the micropores on all the spray film-making tubes 416 is equal to the cross-sectional area of ​​the mixed salt wastewater spray delivery tube 417. The design of the position, direction and number of the micropores ensures that the spray liquid can be sprayed without dead angles, and the mist water is evenly distributed on the walls of the first steam input pipe 411, the first steam output pipe 412, the first small circular heating coil 413 and the first large circular heating coil 414 and the inner wall of the thin film flash evaporator 400, forming a uniform water film layer, thereby increasing the efficiency of thin film flash evaporation.

[0069] The mixed salt wastewater spraying and conveying pipe 417 is arranged vertically, and its top end is connected to the center of the lower surface of the mixed salt wastewater distribution disc 415, and its bottom end is connected to the outlet pipe of the spray pump 422. Through the design of the spray pump 422 and the mixed salt wastewater spraying and conveying pipe 417, the mixed salt wastewater in the liquid storage bin 420 is returned to the mixed salt wastewater distribution disc 415, and the pressure of the mixed salt wastewater in the mixed salt wastewater distribution disc 415 is increased, so that the mixed salt wastewater in the mixed salt wastewater distribution disc 415 can be sprayed out from the micropores on the spray film-making pipe 416 to form a water film layer for thin film flash evaporation.

[0070] In addition, an umbrella-shaped demister 418 is installed in the flash separation chamber 410 at the mixed salt wastewater distribution disc 415. The umbrella-shaped demister 418 is connected and fixed on the inner wall surface of the flash separation chamber 410 in a parallel and inclined manner.

[0071] Each stage of the evaporation crystallization vortex separator comprises, from top to bottom, a gas-liquid separation chamber I, a vortex separation chamber II and a heating cyclone chamber III.

[0072] The inner wall of the gas-liquid separation chamber I is provided with a steam coil. The inlet end of the steam coil passes through the cylinder of the gas-liquid separation chamber I and is connected to the steam main pipe; the outlet end of the steam coil passes through the cylinder of the gas-liquid separation chamber I and is connected to the steam water collection tank. A defoaming device is also installed on the inner wall of the gas-liquid separation chamber I.

[0073] A tangent input port is provided in the middle part of one side of the outer wall of the cylinder of the vortex separation chamber II, and a tangent output port is provided in the upper part of the outer wall of the cylinder of the heating cyclone chamber III, and the tangent input port and the tangent output port are respectively connected to the outlet and the inlet of the forced circulation pump 700 through pipelines. A cyclone light phase layer mixed salt wastewater outlet pipe 710 is also connected to the pipeline between the tangent input port and the outlet of the forced circulation pump 700, and the cyclone light phase layer mixed salt wastewater outlet pipe 710 is connected to the liquid inlet of the next stage evaporation crystallization vortex separator, and the cyclone light phase layer mixed salt wastewater outlet pipe 710 of the third stage evaporation crystallization vortex separator 300 is connected to the liquid inlet of the first stage evaporation crystallization vortex separator 100. The cyclone light phase layer mixed salt wastewater outlet pipe 710 is used to transport the light phase mixed salt wastewater after the crystallization salt is separated in the evaporation crystallization vortex separator to the next stage evaporation crystallization vortex separator.

[0074] A vortex deflector and an evaporation heater are installed in the inner cavity of the heating cyclone chamber III.

[0075] Specifically, the vortex deflector includes a funnel 810 and a guide tube 820. The large-diameter end of the funnel 810 is located at the top of the heating cyclone chamber III, and the small-diameter end is connected to the top of the guide tube 820. The bottom of the guide tube 820 is suspended above the bottom of the heating cyclone chamber III.

[0076] The evaporation heater is located outside the vortex guide device, and includes a second steam input pipe 910 , a second steam output pipe 920 , a plurality of second small circular heating coils 930 , and a plurality of second large circular heating coils 940 .

[0077] The bottom end of the second steam input pipe 910 is a closed end. The top end of the second steam input pipe 910 in the first-stage evaporation crystallization vortex separator 100 is connected to the steam main pipe.

[0078] The top end port of the second steam input pipe 910 in the second-stage evaporation crystallization vortex separator 200 is connected to the gas-liquid separation chamber I of the first-stage evaporation crystallization vortex separator 100 through the secondary steam vacuum pipe 500 .

[0079] The top end of the second steam input pipe 910 in the third-stage evaporation crystallization vortex separator 300 is connected to the flash separation chamber 410 and the first steam output pipe 412 of the thin film flash evaporator 400 through the secondary steam vacuum pipe 500 .

[0080] The top end of the second steam output pipe 920 is a closed end. The bottom end of the second steam output pipe 920 in the first-stage evaporation crystallization vortex separator 100 is connected to the steam water collection tank.

[0081] The bottom end port of the second steam output pipe 920 in the second-stage evaporation crystallization vortex separator 200 is connected to the first steam input pipe 411 of the thin film flash evaporator 400 through a secondary steam vacuum pipe.

[0082] The bottom end port of the second steam output pipe 920 in the third-stage evaporation crystallization vortex separator 300 is connected to the shell inlet of the heat exchanger 1000 through a secondary steam vacuum pipe. The shell inlet of the heat exchanger 1000 is also connected to the gas-liquid separation chamber in the third-stage evaporation crystallization vortex separator 300 through a secondary steam vacuum pipe.

[0083] In each stage of the evaporation crystallization vortex separator, the plurality of groups of second small circular heating coils 930 are arranged from top to bottom between the second steam input pipe 910 and the second steam output pipe 920, and the steam input port of each group of second small circular heating coils 930 is connected to the second steam input pipe 910, and the steam output port thereof is connected to the second steam output pipe 920. The longitudinal heights of the groups of second small circular heating coils 930 are the same.

[0084] In each stage of the evaporation crystallization vortex separator, the plurality of groups of second large circular heating coils 940 are sleeved on the second steam input pipe 910 and the second steam output pipe 920 from top to bottom, and the steam input port of each group of second large circular heating coils 940 is connected to the second steam input pipe 910, and the steam output port thereof is connected to the second steam output pipe 920. The longitudinal heights of the groups of second large circular heating coils 940 are the same.

[0085] In the same level evaporation crystallization vortex separator, the sum of the cross-sectional areas of the second small circular heating coil 930 and the second large circular heating coil 940 is equal to the cross-sectional area of ​​the second steam input pipe 910, ensuring that the steam from the second steam input pipe 910 is evenly distributed in each circular heating coil, avoiding short circuit and ensuring smooth input and discharge of hot steam.

[0086] A semicircular steam coil 950 is also wound on the outer wall of the heating vortex chamber III, and the inlet end of the semicircular steam coil 950 is connected to the steam main pipe, and the outlet end thereof is connected to the steam water collection tank.

[0087] The liquid inlet is provided in the middle of one side of the cylinder wall of the heating cyclone chamber III. A first magnetic flow promoter 960 is installed on the cylinder wall opposite to the liquid inlet, and a second magnetic flow promoter 970 is installed at the bottom end of the cylinder wall on the same side as the liquid inlet.

[0088] The bottom of the heating cyclone chamber III of each level of the evaporation crystallization vortex separator is provided with a crystallization material outlet.

[0089] Under the action of the first magnetic flow propeller 960, the light-phase mixed salt wastewater without crystallized salt swirls in the upper half of the heating cyclone chamber III. Most of this part of the mixed salt wastewater is transported to the cyclone separation chamber under the action of the forced circulation pump 700. Under the action of the tangent input port, the light-phase mixed salt wastewater is vortex-separated in the vortex separation chamber.

[0090] Under the action of the second magnetic flow promoter 970, the heavy phase layer containing the crystallized salt swirls in the lower half of the heating swirl chamber III, and the crystallized material sinks under the action of gravity and finally flows out from the crystallized material outlet.

[0091] Through the design of the forced circulation pump 700, non-seed mixed salt wastewater (i.e., light-phase mixed salt wastewater without salt seeds and crystallized salt) can repeatedly enter the evaporation crystallization separator for repeated heating and crystallization, and repeat cyclone stratification and vortex water vapor separation under the thrust of the first magnetic flowmaker 960 and the second magnetic flowmaker 970, and cyclone stratification of heavy-phase mixed salt wastewater containing crystallized salt and light-phase mixed salt wastewater without crystallized salt, with low energy consumption and twice the result with half the effort in crystallization separation effect.

[0092] The crystallized material outlet is connected to the liquid inlet of the hot filter dryer 1100 through a pipeline. The crystallized material enters the hot filter dryer 1100 through the pipeline for dehydration and drying to obtain the corresponding salt product.

[0093] The outside of the gas-liquid separation chamber I of the evaporation crystallization vortex separators at each stage is also wrapped with a steam coil, the inlet end of the steam coil is connected to the steam main pipe, and the outlet end is connected to the steam inlet of the corresponding hot filter dryer 1100; the separation liquid outlet of each hot filter dryer 1100 is connected to the liquid inlet of the next stage evaporation crystallization vortex separator, and the steam outlet is connected to the steam inlet of the preheater through a pipeline, thereby realizing multi-stage utilization of hot steam resources and improving energy utilization.

[0094] A water ring vacuum pump 1200 and a cooling tower 1300 are also installed between the heat exchanger 1000 and the preheater 600. The steam outlet of the preheater is connected to the pipe layer inlet of the heat exchanger 1000 after passing through the cooling tower 1300. The water ring vacuum pump 1200 is installed between the heat exchanger 1000 and the cooling tower 1300.

[0095] Specifically, sodium sulfate seed crystals are placed in the first-stage evaporation crystallization vortex separator 100, and the crystallization temperature of the sodium sulfate is controlled to be 100-105°C.

[0096] Sodium chloride seed crystals are placed in the second-stage evaporation crystallization vortex separator 200, and the crystallization temperature of sodium chloride is controlled to be 80-90°C.

[0097] Ammonium chloride seed crystals are placed in the third-stage evaporation crystallization vortex separator 300, and the crystallization temperature of the ammonium chloride is controlled to be 50-60°C.

[0098] Through the design of the semicircular steam coil on the outer wall of the heating cyclone chamber III of each stage of the evaporation crystallization vortex separator, on the one hand, the structural strength of the container is strengthened, and on the other hand, the crystallization temperature required for the salt in each stage of the evaporation crystallization vortex separator can be regulated.

[0099] The above-mentioned processing device carries out multi-stage steam recycling, effectively saving the consumption of fresh steam and saving energy.

[0100] Specifically, in this embodiment, the cold mixed salt wastewater is heat exchanged with the waste heat of steam water through a preheater, thereby saving 7.5% of fresh steam, and the hot air from the filter dryer is recycled to save another 7.5% of fresh steam.

[0101] The method for regenerating mixed salt wastewater resources using the above-mentioned treatment device specifically comprises the following steps:

[0102] (1) Adding salt seeds: a certain amount of sodium sulfate seeds are added into the first-stage evaporation crystal vortex separator 100; a certain amount of sodium chloride seeds are added into the second-stage evaporation crystal vortex separator 200; and a certain amount of ammonium chloride seeds are added into the third-stage evaporation crystal vortex separator 300.

[0103] (2) Flash concentration: The mixed salt wastewater is first pumped from the mixed salt wastewater storage tank 1400 to the preheater 600, and after preheating, it is transported to the mixed salt wastewater distribution disk 415 of the thin film flash evaporator 400, and then enters the spray film-forming tube 416 through the spray liquid distribution port, and flows out from the micropores on the spray film-forming tube 416 and is collected in the liquid storage bin 420.

[0104] Under the action of the spray pump 422, most of the mixed salt wastewater in the liquid storage bin 420 is returned to the mixed salt wastewater distribution disc 415 through the mixed salt wastewater spray delivery pipe 417, and enters the spray film-forming pipe 416 from the spray liquid distribution port of the mixed salt wastewater distribution disc 415 together with the preheated mixed salt wastewater, and is sprayed out from the micropores on the spray film-forming pipe 416, forming a water film layer on the inner wall of the thin film flash evaporator and the outer wall of the flash heater, and performing thin film flash evaporation. The hot water vapor generated by the flash evaporation is discharged in the umbrella-shaped demister. Under the action of 418, gas-liquid separation is carried out, and the steam obtained by gas-liquid separation is discharged from the top to the secondary steam vacuum tube, and transported to the second steam input pipe in the third-stage evaporation crystallization vortex separator 300; the mixed salt wastewater with a total salt concentration close to the saturated solution state obtained by gas-liquid separation is collected again in the liquid storage bin 420, among which a small part of the mixed salt wastewater with a total salt concentration close to the saturated solution state is transported from the outlet branch pipeline to the first-stage evaporation crystallization vortex separator 100 through the concentrated brine discharge pipe 421 and the spray pump 422.

[0105] (4) Evaporation and crystallization of sodium sulfate: mixed salt wastewater with a total salt concentration close to the saturated solution state enters from the liquid inlet in the middle of the heating cyclone chamber of the first-stage evaporation and crystallization vortex separator 100, and continues to evaporate and lose water under the action of the evaporation crystallizer. The temperature in the heating cyclone chamber is controlled between 100 and 105°C, and crystallization is carried out under the action of sodium sulfate seed crystals;

[0106] Under the action of the first magnetic flow pusher 960, the light-phase mixed salt wastewater without crystallized salt swirls in the upper half of the heating cyclone chamber. Most of this part of the mixed salt wastewater is transported to the cyclone separation chamber under the action of the forced circulation pump 700. Under the action of the tangent input port, the light-phase mixed salt wastewater is vortex-separated in the vortex separation chamber, and hot water vapor is generated on the vortex separation liquid surface. Under the action of the defoaming device in the gas-liquid separation chamber, the separated steam flows upward into the secondary steam vacuum pipe and enters the second steam input pipe 910 in the second-stage evaporation crystallization vortex separator 200; the separated liquid flows back to the heating cyclone chamber with the circulating liquid under the action of the vortex guide pipe 820 to continue evaporation and cyclone stratification; at the same time, a small part of the light-phase mixed salt wastewater enters the second-stage evaporation crystallization vortex separator 200 through the cyclone light phase layer mixed salt wastewater outlet pipe for application;

[0107] Under the action of the second magnetic flow promoter 970, the heavy phase layer containing the crystallized salt swirls in the lower half of the heated cyclone chamber, and the crystallized material sinks under the action of gravity, and finally flows out from the crystallized material outlet and enters the corresponding hot filter dryer 1100, and is filtered and dried to obtain sodium sulfate, i.e., the first salt product.

[0108] (5) Evaporation and crystallization of sodium chloride: The mixed salt wastewater entering the second-stage evaporation and crystallization vortex separator 200 repeats the evaporation process in step (4), and the temperature in the heating cyclone chamber is controlled to be 80-90° C., and crystallization is carried out under the action of sodium chloride seed crystals;

[0109] The mixed salt wastewater containing the crystalline component repeats the cyclone separation process in step (4), and is finally hot filtered and dried to obtain sodium chloride, i.e., the second salt product. Part of the light phase mixed salt wastewater enters the third-stage evaporative crystallization vortex separator 300 through the cyclone light phase layer mixed salt wastewater outlet pipe for application.

[0110] (6) Evaporation and crystallization of ammonium chloride: The mixed salt wastewater entering the third-stage evaporation and crystallization vortex separator 300 repeats the evaporation process in step (4), and the temperature in the heating cyclone chamber is controlled to be 50-60° C., and crystallization is carried out under the action of ammonium chloride seed crystals;

[0111] The mixed salt wastewater containing the crystalline component repeats the cyclone separation process in step (4), and is finally hot filtered and dried to obtain ammonium chloride, i.e., the third salt product. Part of the light phase mixed salt wastewater passes through the cyclone light phase layer mixed salt wastewater outlet pipe and then enters the first-stage evaporation crystallization vortex separator 100 for application, and steps (4) to (6) are repeated until the mixed salt wastewater is evaporated into industrial water and the salt in the mixed salt wastewater is crystallized into clean sodium sulfate, sodium chloride and ammonium chloride respectively.

[0112] The processing method of the present invention can effectively save energy consumption, as follows:

[0113] One ton of fresh steam is input into the first-stage evaporation crystallization vortex separator, and one ton of water can be evaporated and lost under the conditions of a vacuum degree of -0.02 MRa and a temperature of 105°C; the secondary steam generated by the first-stage evaporation crystallization vortex separator is used to heat the second-stage evaporation crystallization vortex separator, and 0.8 tons of water can be evaporated and lost under the conditions of a vacuum degree of -0.04 MPa and a temperature of 90°C; the secondary steam generated by the second-stage evaporation crystallization vortex separator is used to heat the thin film flash evaporator, and 2.5 tons of water can be flash evaporated and lost under the conditions of a vacuum degree of -0.07 MPa and a temperature of 80°C. The secondary steam produced by the thin film flash evaporator heats the third-stage evaporation crystallization vortex separator. Under the conditions of a vacuum degree of -0.08MPa and a temperature of 50°C, 0.8 tons of water can be evaporated. That is, the steam consumption of this process technology facility for evaporating one ton of mixed salt wastewater is 1÷5.1×85% = 0.17 tons / per ton of wastewater, which is 1 / 2 of the steam energy consumption of a conventional three-effect evaporator and saves 6% steam compared to an NVR evaporator.

[0114] In addition, the evaporation crystallization vortex separator of this embodiment can realize zero-lift forced circulation, and is equipped with a magnetic flow promoter, which can evaporate and treat 6 tons of wastewater per hour, and the installed capacity is 70Kw / hour, which is 35% of the conventional evaporation facility installed capacity of 200tw / hour.

[0115] The device of this embodiment consumes 12.8 degrees of electricity for evaporating 1 ton of mixed salt wastewater, which is 33 degrees less than the conventional evaporator for evaporating one ton of wastewater.

[0116] The treatment device of this embodiment treats wastewater at a scale of 6 tons / hour, with an equipment investment of 1.6 million. Compared with a conventional triple-effect evaporator or NVR evaporator of the same scale with an investment of 2 million, the investment is reduced by 1.2 million, saving 57% of the equipment cost.

[0117] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A mixed salt wastewater resource regeneration treatment device, characterized in that: include: A thin film flash evaporator and an N-stage evaporation crystallization vortex separator, where N is an integer greater than or equal to 2; The thin film flash evaporator includes a flash separation chamber and a liquid storage tank from top to bottom; a mixed salt wastewater distribution component is installed in the internal cavity of the flash separation chamber, and the mixed salt wastewater storage tank is connected to the mixed salt wastewater distribution component through a pipeline; the bottom end of the liquid storage tank is connected to the liquid inlet of the N-stage evaporation crystallization vortex separator in sequence through a concentrated brine discharge pipe; Each level of the evaporation and crystallization vortex separator includes a gas-liquid separation chamber, a vortex separation chamber and a heating cyclone chamber from top to bottom; the shells of the vortex separation chamber and the heating cyclone chamber are respectively provided with a tangent input port and a tangent output port; the tangent input port and the tangent output port are respectively connected to the outlet and the inlet of the forced circulation pump; the pipeline between the tangent input port and the outlet of the forced circulation pump is also connected to a cyclone light phase layer mixed salt wastewater outlet pipe; in the N-level evaporation and crystallization vortex separators, the cyclone light phase layer mixed salt wastewater outlet pipe of the previous stage evaporation and crystallization vortex separator is connected to the liquid inlet of the next stage evaporation and crystallization vortex separator, and the cyclone light phase layer mixed salt wastewater outlet pipe of the last stage evaporation and crystallization vortex separator is connected to the liquid inlet of the first stage evaporation and crystallization vortex separator; The bottom of each stage of the evaporation crystallization vortex separator is provided with a crystallization material outlet, which is connected to a filter dryer through a pipeline; Salt seeds consistent with the salt product evaporated and crystallized are placed in each stage of the evaporation and crystallization vortex separator; Heaters are installed in the internal cavities of the flash separation chamber and the heating cyclone chamber, and the heaters include a steam input pipe, a steam output pipe, a plurality of groups of small circular heating coils and a plurality of groups of large circular heating coils; A vortex guide is also installed in the heating cyclone chamber of the evaporation crystallization vortex separator, and the vortex guide includes a funnel and a guide tube; the large-diameter end of the funnel is connected to the top of the heating cyclone chamber, and the small-diameter end is connected to the top end of the guide tube, and the bottom of the guide tube is suspended above the bottom of the heating cyclone chamber; The liquid inlet of the evaporation and crystallization vortex separator is located on the middle cylinder wall of the vortex separation chamber, and a first magnetic flow promoter is installed on the cylinder wall of the vortex separation chamber on the opposite side of the liquid inlet; the second magnetic flow promoter is installed at the bottom of the cylinder wall of the heating cyclone chamber on the same side of the liquid inlet.

2. A mixed salt wastewater resource regeneration treatment device according to claim 1, characterized in that: The top end port of the steam input pipe is connected to the fresh steam pipe or the secondary steam vacuum pipe, and the bottom end port thereof is closed; The top end port of the steam output pipe is closed, and the bottom end port thereof is connected to a secondary steam vacuum pipe or a steam water collecting tank; The multiple groups of large circular heating coils are wound on the steam input pipe and the steam output pipe from top to bottom, the steam input port of each group of the large circular heating coils is connected to the steam input pipe, and the steam output port of each group of the large circular heating coils is connected to the steam output pipe; and the steam input port of the same group of large circular heating coils is at the top, and the steam output port is at the bottom; Multiple groups of small circular heating coils are arranged from top to bottom between the steam input pipe and the steam output pipe, the steam input port of each group of small circular heating coils is connected to the steam input pipe, and the steam output port of each group of small circular heating coils is connected to the steam output pipe; and the steam input port of the same group of small circular heating coils is at the top, and the steam output port is at the bottom.

3. The mixed salt wastewater resource regeneration treatment device according to claim 2 is characterized in that: The mixed salt wastewater distribution component is located in the inner cavity of the flash separation chamber of the thin film flash evaporator; the mixed salt wastewater distribution component includes a mixed salt wastewater distribution disc, a mixed salt wastewater input pipe, a mixed salt wastewater spray delivery pipe and a plurality of spray film-making pipes; The mixed salt wastewater distribution disc is installed in the upper middle part of the heater, the center of its upper surface is connected to the mixed salt wastewater input pipe, the center of its lower surface is connected to the mixed salt wastewater spray delivery pipe, and a plurality of spray liquid distribution ports are arranged around its side, and the spray liquid distribution ports are connected to the spray film forming pipe; The spray film-forming tube is installed in the area between the large circular heating coil and the small circular heating coil, with its top end connected to the mixed salt wastewater distribution disc and its bottom end closed; each of the spray film-forming tubes is provided with micropores.

4. The mixed salt wastewater resource regeneration treatment device according to claim 3 is characterized in that: The micropores are located on the wall of the spray film-forming tube corresponding to the gap between the upper coil and the lower coil of the large circular heating coil and on the wall of the spray film-forming tube corresponding to the gap between the upper coil and the lower coil of the small circular heating coil.

5. The mixed salt wastewater resource regeneration treatment device according to claim 4 is characterized in that: A spray pump is installed on the concentrated brine discharge pipe, the outlet pipe of the spray pump is connected to the bottom end of the mixed salt wastewater spray delivery pipe, and its outlet branch pipe is connected to the liquid inlet of the next stage evaporation crystallization vortex separator.

6. The mixed salt wastewater resource regeneration treatment device according to claim 5 is characterized in that: A semicircular steam coil is wound on the outer wall of the cylinder of the heating vortex chamber. The inlet end of the semicircular steam coil is connected to the fresh steam pipe, and the outlet end is connected to the steam water collecting tank.

7. The mixed salt wastewater resource regeneration treatment device according to claim 5 is characterized in that: The mixed salt wastewater storage tank is connected to the mixed salt wastewater input pipe in the mixed salt wastewater distribution component through a pipeline, and a preheater is also installed on the pipeline between the mixed salt wastewater storage tank and the mixed salt wastewater input pipe.

8. A method for regenerating mixed salt wastewater resources, characterized in that: The method is carried out in a processing device according to any one of claims 6 or 7, comprising the steps of: (1) Adding salt seeds: Add appropriate amount of salt seeds of the same type as the evaporation and crystallization salt products into each level of evaporation and crystallization vortex separator; (2) Flash concentration: The mixed salt wastewater is transported to the mixed salt wastewater distribution disk of the thin film flash evaporator, flows out through the micropores on the spray film tube, and is collected in the liquid storage bin; Under the action of the spray pump, the mixed salt wastewater in the liquid storage bin is returned to the mixed salt wastewater distribution disc through the mixed salt wastewater spray delivery pipe, and then sprayed onto the inner wall of the thin film flash evaporator and the outer wall of the flash heater through the spray film forming pipe to form a water film layer, and thin film flash evaporation is performed. The gas after flash evaporation is discharged from the top of the thin film flash evaporator for reuse, and the liquid is concentrated into mixed salt wastewater with a total salt concentration close to saturation. Part of the mixed salt wastewater with a total salt concentration close to saturation is transported to the first-stage evaporation crystallization vortex separator through the outlet branch pipeline; (3) Evaporation and crystallization of the first salt product: the mixed salt wastewater with a total salt concentration close to saturation entering the first-stage evaporation and crystallization vortex separator continues to evaporate under the action of the heater, and the first salt product is crystallized under the initiation of the first salt seed crystal. The heavy phase mixed salt wastewater containing the crystallized salt swirls and sinks, and is discharged through the crystallization material outlet, and the first salt is dried and recovered; the light phase mixed salt wastewater swirls in the vortex separation chamber under the action of the forced circulation pump, and at the same time, part of the light phase mixed salt wastewater flows into the next stage evaporation and crystallization vortex separator through the swirl light phase layer mixed salt wastewater outlet pipe for application; (4) Evaporation and crystallization of the Nth salt product: The mixed salt wastewater entering the Nth stage evaporation and crystallization vortex separator repeats the process in step (3) to obtain the Nth salt product, and the light phase mixed salt wastewater then flows into the first stage evaporation and crystallization vortex separator through the cyclone light phase layer mixed salt wastewater outlet pipe for application, and the evaporation and crystallization are circulated in this way until the mixed salt wastewater is evaporated into industrial water.

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