New process system and method for full resource treatment of phenol and ammonia in coking and coke-oven wastewater

Abstract

The application discloses a new process system and method for full resource treatment of coking and coke-oven wastewater phenol and ammonia, and belongs to the technical field of industrial wastewater treatment. The system comprises, in sequence, a forced air pressure acidification and tar creosote recovery module, a decontamination and solid-liquid separation module, a gradient desalination and ultrahigh pressure concentration module, and a reduced pressure evaporation and chemical fertilizer extraction module. The forced air pressure acidification and tar creosote recovery module comprises an acidification reaction kettle for receiving coking / coke-oven wastewater, and the acidification reaction kettle is connected with an adsorption column group. The decontamination and solid-liquid separation module comprises a pretreatment tank connected with the adsorption column group, and the pretreatment tank is connected with a TMF microfiltration. The reduced pressure evaporation and chemical fertilizer extraction module is used for producing composite chemical fertilizer. The application improves the tar creosote recovery rate by using pre-acidification and specific resin adsorption, retains ammonia nitrogen in the system, realizes directional crystallization of inorganic ions by gradient reduced pressure evaporation, and directly produces large-particle standard-compliant composite chemical fertilizer of ammonium sulfate and ammonium chloride.

Description

Technical Field

[0001] This invention belongs to the field of industrial wastewater treatment technology, and in particular relates to a new process system and method for the full resource utilization treatment of phenols and ammonia in coking and semi-coke wastewater. Background Technology

[0002] Coking wastewater and semi-coke wastewater are extremely difficult-to-treat industrial wastewaters generated during the highly complex physicochemical processes of high-temperature coal distillation, coal gas purification, and chemical product refining. The raw water composition is complex, containing extremely high concentrations of organic pollutants. Actual measurement data shows that over 80% of the organic pollutants in coking wastewater are phenols, while in semi-coke wastewater, this proportion reaches as high as 99%. In addition, the wastewater also contains high concentrations of free ammonia nitrogen, cyanide, and easily scale-forming silicates and fluorides.

[0003] Traditional coking wastewater treatment processes typically employ a route of "ammonia stripping tower deammoniation - biochemical and deep degradation treatment - dual-alkali softening and precipitation - ultrafiltration and reverse osmosis membrane concentration and volume reduction - terminal forced evaporation crystallization." However, this process has serious drawbacks: First, to disrupt the ammonia-nitrogen balance, the front-end ammonia stripping tower requires the addition of a large amount of caustic soda (approximately 4 kg) per ton of wastewater and consumes a significant amount of low-pressure steam (100-150 kg), resulting in high infrastructure and operating costs. Second, because the system adopts a thorough biodegradation strategy for high-value-added phenolic substances, the biotoxicity of phenols can easily cause the biochemical system to collapse; furthermore, the degradation of high-value chemicals into carbon dioxide and water leads to significant resource misallocation and waste. Finally, traditional terminal evaporation crystallization produces extremely complex mixed salts, which are classified as hazardous waste, incurring extremely high disposal costs and being non-recyclable, imposing a heavy economic and environmental burden on enterprises. Summary of the Invention

[0004] The purpose of this invention is to provide a new process system and method for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater, so as to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solution: The present invention provides a novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater, comprising a forced air pressure acidification and phenol recovery module, a purification and solid-liquid separation module, a gradient desalination and ultra-high pressure concentration module, and a reduced pressure evaporation and fertilizer extraction module connected in sequence. The forced air pressure acidification and phenol recovery module includes an acidification reactor for receiving coking / semi-coke wastewater. The acidification reactor is connected to an adsorption column group, which is connected to the purification and solid-liquid separation module. The purification and solid-liquid separation module includes a pretreatment tank connected to the adsorption column group. The pretreatment tank is connected to a TMF microfiltration system, which is connected to the gradient desalination and ultra-high pressure concentration module. The reduced pressure evaporation and fertilizer extraction module is used to produce compound fertilizer.

[0006] Optionally, the top of the acidification reactor is equipped with an H2SO4 dosing pipeline, the acidification reactor is equipped with a high-pressure liquid distributor and a first stirring mechanism, and the bottom outlet pipeline of the acidification reactor is connected to the adsorption column group in series through a high-pressure chemical shielded pump.

[0007] Optionally, the adsorption column group is equipped with a special adsorption material for the synthesis of phenol molecules, the side end of the adsorption column group is connected to a steam / alkali washing desorption pipeline, the desorption outlet of the adsorption column group is connected to a high-purity phenol recovery pipeline, and the main water outlet of the adsorption column group is connected to the pretreatment tank.

[0008] Optionally, the top of the pretreatment tank is provided with a dosing mechanism for adding multi-nuclear desiliconization and fluorine removal agents, and the pretreatment tank is provided with a second stirring mechanism.

[0009] Optionally, the pretreatment tank is connected to the inlet manifold of the TMF microfilter via a water supply circulation pump, and a plate and frame filter press is connected to the bottom of the TMF microfilter.

[0010] Optionally, the gradient desalination and ultra-high pressure concentration module includes a UF+RO staged membrane, which is connected to the TMF microfiltration. The desalinated soft water produced by the UF+RO staged membrane is directly led out of the system, and the concentrated water with a salt content of 10-20% produced by the UF+RO staged membrane is transported to the DTRO ultra-high pressure concentration unit through a high-pressure pipeline.

[0011] Optionally, the DTRO ultra-high pressure concentration module is made of alternating stacked guide plates and reverse osmosis membrane bags. The guide plates are provided with multiple guide columns arranged in a logarithmic spiral pattern. The DTRO ultra-high pressure concentration module is connected to the reduced pressure evaporation and fertilizer extraction module.

[0012] Optionally, the reduced pressure evaporation and fertilizer extraction module includes a reduced pressure triple-effect evaporation system connected to the DTRO ultra-high pressure concentration component. The reduced pressure triple-effect evaporation system includes a first-effect evaporator, a second-effect evaporator, and a third-effect evaporator connected in series. The third-effect evaporator is connected to a crystallization separation centrifuge.

[0013] Optionally, the reduced pressure triple-effect evaporation system is used to receive the 25% concentrated mother liquor produced by the DTRO ultra-high pressure concentration module.

[0014] A novel process for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater includes the following steps: S1. Pre-processed forced pressure acidification and limited directional adsorption and recovery of phenols: The raw wastewater containing high concentrations of free ammonia and phenols is introduced into the acidification reactor to adjust the pH value in the acidification reactor and stabilize it in the acidic range. S2. Multi-core agent complexation for fluoride and silicon removal and TMF fluid circulation microfiltration: The wastewater treated in step S1 enters the pretreatment tank, and multi-core composite agent is added to the pretreatment tank for fluoride and silicon removal. S3. The whole membrane graded gradient desalination and ultra-high pressure DTRO concentration are used to send the purified water into the UF+RO graded composite membrane. The desalinated soft water produced is directly reused in the plant production, and the remaining concentrated water enters the DTRO ultra-high pressure concentration module for further treatment. S4. Gradient reduced pressure triple-effect evaporation crystallization and fertilizer production: 25% concentration mother liquor is directly pumped into the reduced pressure triple-effect evaporation system. The produced high-purity fertilizer is then separated by two-stage centrifugation in a crystallization separation centrifuge and packaged for shipment.

[0015] This invention discloses the following technical effects: It utilizes pre-acidification and specific resin adsorption to improve the recovery rate of phenols, transforming deadly toxins in the biochemical system into high-value-added fine chemical raw materials that can be directly sold; it retains ammonia nitrogen in the system and uses gradient vacuum evaporation to achieve directional crystallization of inorganic ions, directly producing large-particle, standard-compliant ammonium sulfate and ammonium chloride compound fertilizers; the reduction rate of hazardous waste from miscellaneous salts is >95%, eliminating high outsourced treatment costs; by coupling TMF microfiltration barriers and multi-core composite impurity removal agents, the effluent SDI is <3, eliminating the scaling risks of ultrafiltration and RO membranes from the source. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the new process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater according to the present invention.

[0017] Figure label: 1. Acidification reactor; 2. Adsorption column group; 3. Pretreatment tank; 4. TMF microfiltration; 5. Plate and frame filter press; 6. UF+RO fractionation membrane; 7. DTRO ultra-high pressure concentration module; 8. Reduced pressure triple-effect evaporation system; 9. Crystallization separation centrifuge. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Reference Figure 1 As shown, this embodiment provides a new process system for the full resource utilization of phenols and ammonia in coking and semi-coke wastewater. It includes a forced air pressure acidification and phenol recovery module, a purification and solid-liquid separation module, a gradient desalination and ultra-high pressure concentration module, and a reduced pressure evaporation and fertilizer extraction module connected in sequence. The forced air pressure acidification and phenol recovery module includes an acidification reactor 1 for receiving coking / semi-coke wastewater. The acidification reactor 1 is connected to an adsorption column group 2, which is connected to the purification and solid-liquid separation module. The purification and solid-liquid separation module includes a pretreatment tank 3 connected to the adsorption column group 2. The pretreatment tank 3 is connected to a TMF microfiltration 4, which is connected to the gradient desalination and ultra-high pressure concentration module. The reduced pressure evaporation and fertilizer extraction module is used to produce compound fertilizer.

[0021] This invention utilizes pre-acidification and specific resin adsorption to improve the recovery rate of creosote, transforming deadly toxins in the biochemical system into high-value-added fine chemical raw materials that can be directly sold. Ammonia nitrogen is retained in the system, and gradient vacuum evaporation is used to achieve directional crystallization of inorganic ions, directly producing large-particle, standard-compliant ammonium sulfate and ammonium chloride compound fertilizers. The reduction rate of hazardous waste from miscellaneous salts is over 95%, eliminating the high cost of outsourced treatment. By coupling TMF microfiltration four-barrier and multi-core composite impurity removal agents, the effluent SDI is reduced to <3, eliminating the risk of scaling on ultrafiltration and RO membranes at the source.

[0022] To further optimize the design, the top of the acidification reactor 1 is equipped with an H2SO4 dosing pipeline, and the acidification reactor 1 is equipped with a high-pressure liquid distributor and a first stirring mechanism. The bottom water outlet pipeline of the acidification reactor 1 is connected to the series adsorption column group 2 through a high-pressure chemical shielded pump.

[0023] The top of the acidification reactor 1 is equipped with a raw water inlet pipe and an H2SO4 dosing pipe for receiving coking / semi-coke wastewater and adjusting the pH value of the system. The acidification reactor 1 is preferably equipped with a specially designed high-pressure liquid distributor (such as a trapezoidal hollow pipe and a frustum-shaped wastewater spray nozzle) and a first stirring mechanism to ensure the instantaneous and rapid mixing of strong acid and high-concentration wastewater and the uniformity of the protonation reaction, so as to promote the conversion of dissolved sodium phenolate into free phenols and the in-situ combination of free ammonia with sulfuric acid to generate stable ammonium sulfate.

[0024] The scheme is further optimized by installing special adsorption materials, such as MOF / COF materials, for the synthesis of phenolic molecules in adsorption column group 2. The side end of adsorption column group 2 is connected to a steam / alkali elution pipeline for reverse elution of saturated adsorption materials. The desorption outlet of adsorption column group 2 is connected to a high-purity phenol recovery pipeline to realize the commercial extraction of high-value-added chemicals. The main water outlet of adsorption column group 2 is connected to the pretreatment tank 3.

[0025] To further optimize the scheme, the top of the pretreatment tank 3 is equipped with a dosing mechanism for adding multi-core silicon-removing fluoride agents, and the pretreatment tank 3 is equipped with a second stirring mechanism.

[0026] The pretreatment tank 3 receives the main effluent from the adsorption column group 2. A dedicated dosing mechanism is located at the top of the tank. The pretreatment tank 3 is used for the precise dosing of multi-nuclear silicon and fluoride removal agents (such as calcium chloride, sodium aluminate, sodium carbonate, and polyaluminum chloride). Under the stirring action of the second stirring mechanism within the pretreatment tank 3, a precipitate suspension mixture containing silica and fluoride ions is generated.

[0027] The scheme was further optimized. The pretreatment tank 3 was connected to the inlet manifold of the TMF microfiltration 4 through the water supply circulation pump to form a closed-loop filtration circuit with high cross-flow velocity. The fluid was forced to circulate in the microporous tube, and the clear liquid flowed vertically through the micropores into the next stage membrane system. The high-concentration mud-water mixture that was completely intercepted was collected at the bottom sludge discharge blind end. The bottom of the TMF microfiltration 4 was connected to the plate and frame filter press 5, where the inorganic precipitated sludge was squeezed, dewatered and solidified, which completely eliminated the risk of inorganic scaling of the subsequent reverse osmosis membrane from the source.

[0028] The scheme is further optimized. The gradient desalination and ultra-high pressure concentration module includes a UF+RO staged membrane 6. The UF+RO staged membrane 6 is connected to the TMF microfiltration 4. The desalinated soft water produced by the UF+RO staged membrane 6 is directly led out of the system. The concentrated water with a salt content of 10-20% produced by the UF+RO staged membrane 6 is transported to the DTRO ultra-high pressure concentration module 7 through a high-pressure pipeline.

[0029] The UF+RO staged membrane 6 receives the purified water from the TMF microfiltration 4. The UF+RO staged membrane 6 operates under normal pressure, producing high-quality desalinated soft water that is directly led out of the system and reused in the plant's production; the concentrated water with a salt content of about 15% is retained and transported to the next unit through a high-pressure pipeline.

[0030] The DTRO ultra-high pressure concentration module 7 is further optimized by being made of alternating stacked guide plates and reverse osmosis membrane bags. The guide plates are equipped with multiple logarithmically spirally arranged guide columns. The DTRO ultra-high pressure concentration module 7 is connected to the vacuum evaporation and fertilizer extraction module.

[0031] The 15% concentrate from the previous stage is injected into the DTRO ultra-high pressure concentration unit 7 by an ultra-high pressure plunger pump. The DTRO ultra-high pressure concentration unit 7 is composed of alternating stacked guide plates and reverse osmosis membrane bags. The surface of the guide plate is specially designed with a large number of logarithmically spirally arranged guide columns. When the ultra-high pressure fluid impacts the group of guide columns with hemispherical tops and threaded sidewalls, it generates strong micro-vortices to achieve in-situ self-cleaning, overcomes the extremely high osmotic pressure, and drastically reduces the amount of concentrate, ultimately producing a 25% concentrated mother liquor close to the crystallization critical point.

[0032] Further optimization of the scheme involves a reduced-pressure evaporation and fertilizer extraction module, including a reduced-pressure triple-effect evaporation system 8 connected to the DTRO ultra-high pressure concentration component 7. This system 8 comprises a first-effect evaporator, a second-effect evaporator, and a third-effect evaporator connected in series. The third-effect evaporator is connected to a crystallization separation centrifuge 9. The reduced-pressure triple-effect evaporation system 8 artificially creates a precise gradient reduced-pressure (negative pressure) environment using a vacuum pump, enabling the gradual utilization of latent heat. Driven by a forced circulation pump, the mother liquor containing extremely high concentrations of inorganic salts is forced to precipitate directionally. The concentrated crystallization slurry containing ammonium sulfate and ammonium chloride undergoes high-speed solid-liquid separation here. At the very end of the system, large-particle compound fertilizer (sulfur / ammonium chloride) meeting agricultural standards is directly produced, completely achieving zero hazardous waste and salt emissions throughout the entire process.

[0033] The scheme was further optimized, and the reduced pressure triple-effect evaporation system 8 was used to receive the 25% concentrated mother liquor produced by the DTRO ultra-high pressure concentration module 7.

[0034] A novel process for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater includes the following steps: S1. Pre-processed forced pressure acidification and limited directional adsorption and recovery of phenols: The raw wastewater containing high concentrations of free ammonia and phenols is introduced into acidification reactor 1 to adjust the pH value in acidification reactor 1 and stabilize it in the acidic range. S2. Multi-core agent complexation for fluoride and silicon removal and TMF fluid circulation microfiltration: The wastewater treated in step S1 enters the pretreatment tank 3, and multi-core composite agent is added to the pretreatment tank 3 for fluoride and silicon removal. S3. The whole membrane graded gradient desalination and ultra-high pressure DTRO concentration are used to send the purified water into the UF+RO graded composite membrane. The desalinated soft water produced is directly reused in the plant production, and the remaining concentrated water enters the DTRO ultra-high pressure concentration module 7 for further treatment. S4. Gradient depressurization triple-effect evaporation crystallization and fertilizer production: 25% concentration mother liquor is directly pumped into depressurization triple-effect evaporation system 8. The produced high-purity fertilizer is separated by two-stage centrifugation in crystallization centrifuge 9 and packaged for shipment.

[0035] Taking a continuously operating, stable engineering water treatment plant with a processing capacity of 50 tons / h of high-concentration coking semi-coke wastewater as an example, the new process for the full resource utilization treatment of phenol and ammonia in coking and semi-coke wastewater includes the following steps: S1. Pre-treatment forced pressure acidification and extreme directional adsorption and recovery of phenols; 7. Completely eliminate the traditional high-energy-consuming deammoniation tower, directly introducing the original wastewater (residual ammonia water) containing high concentrations of free ammonia and phenols into the corrosion-resistant acidification reactor 1. Continuously and quantitatively add 98% industrial sulfuric acid (H2SO4) or hydrochloric acid (HCl) to the acidification reactor 1 to adjust and stabilize the pH of the system in the acidic range (strictly control pH < 5). Two core chemical reactions occur at this time: first, the dissolved sodium phenolate in the wastewater undergoes a protonation displacement reaction, completely converting into free phenols (C6H5ONa+H+→C6H5OH+Na+); second, the free ammonia originally present in the wastewater combines with sulfuric acid to generate stable ammonium sulfate in situ, which enters the aqueous phase, providing precursor substances for end-stage fertilizer production. The acidified wastewater then penetrates a special adsorption column packed with metal-organic framework (COF) material at a flow rate of 3.5 BV / h. After adsorption saturation, the inlet water flow path is cut off, and steam is used for cross-flow counter-current elution. The phenol-rich steam desorption liquid is condensed and further distilled to produce high-purity industrial phenols for sale as chemical raw materials. As an alternative process, sodium hydroxide alkaline solution can also be used directly for desorption, causing the phenols adsorbed inside the material to regenerate sodium phenolate for recycling.

[0036] S2. Multi-core reagent complexation for fluoride and silica removal combined with TMF fluid circulation microfiltration: To eliminate the potential for inorganic scaling in subsequent membrane systems, the adsorbed effluent flows into wastewater pretreatment tank 3, with the temperature controlled between 15℃ and 30℃. Multi-core composite reagents are precisely added to the 50t / h fluid, with strictly controlled dosages: calcium chloride 0.5g / L, sodium aluminate 0.5g / L, sodium carbonate 0.4g / L, and polyaluminum chloride (PAC) 0.6g / L. Simultaneously, 40g / L of activated alumina particles are added as reusable adsorption nuclei. Under controlled pH, magnesium salts generate Mg(OH)2 adsorption colloids to thoroughly remove silica; aluminum and iron salts remove fluoride ions through charge neutralization and entrapment. The mixed water containing the resulting precipitated suspended solids flows into the wastewater concentration tank via overflow non-shear flow, and is then pumped into the TMF tubular microfiltration membrane tube by a circulating water pump. Under the high cross-flow velocity filtration, the sediment is completely trapped in the loop, and the bottom sludge is discharged into the plate and frame filter press 5 for dewatering. This step ensures that the effluent SDI < 3.

[0037] S3. Full-membrane graded desalination and ultra-high pressure DTRO concentration: The purified water is fed into the UF+RO graded membrane 6. Under a pressure of approximately 1.2-1.5 MPa, the system produces 35 tons of high-quality desalinated freshwater (soft water) per hour, which is directly reused in the plant's production. The remaining approximately 15 t / h of RO concentrate (with a salt content of approximately 15%) is slowly passed through a secondary adsorption polishing column filled with adsorption resin to thoroughly remove residual organic matter. Subsequently, the clarified liquid is injected into the DTRO ultra-high pressure concentration module 7 by an ultra-high pressure plunger pump at an operating pressure of 6.8 MPa. Under the strong clockwise / counterclockwise micro-vortex anti-polarization effect caused by the spiral arrangement of the guide plate protrusions, the extremely high osmotic pressure is overcome, and the concentrate is further drastically reduced to below 9 t / h, increasing the salt content of the mother liquor to approximately 25%, close to the crystallization critical point. If DTRO is not used, high-pressure electrodialysis (ED) or cryo-crystallization technology can be used as alternatives at this stage.

[0038] S4. Gradient-reduced pressure triple-effect evaporation crystallization and fertilizer production: 25% concentration mother liquor is directly pumped into the reduced pressure triple-effect evaporation system 8. This system uses a vacuum pump to establish a reduced pressure environment to lower the boiling point of the fluid, realizing the step-by-step utilization of thermal energy. Since the ammonia nitrogen in the raw water has been fixed into sulfate and chloride by adding acid in "step S1", the high-viscosity liquid is driven to flow rapidly by a forced circulation pump, and precise ternary phase diagram material balance control is performed during the crystallization process, forcing the solution to directly and directionally precipitate mixed crystals of ammonium sulfate ((NH4)2SO4) and ammonium chloride (NH4Cl). The produced high-purity fertilizer is separated by two-stage centrifugation and packaged for shipment. Each ton of raw wastewater can produce 40-50 kg of fertilizer-grade salt product, completely realizing the transformation of "solid waste" into "commodity".

[0039] To visually verify the revolutionary advantages of the process system of this invention compared with traditional processes, the following table lists real-world technical comparison data after industrial commissioning.

[0040] Table 1. Measured data on the efficient interception and reduction of organic matter at each stage of the adsorption process of the present invention: As shown in the table above, the forced adsorption interception of the present invention can reduce COD from 9900 mg / L to 1750 mg / L in the pretreatment stage alone, which greatly reduces the load on subsequent treatment.

[0041] Table 2. The deep interception effect of the composite impurity removal agent of the present invention combined with TMF circulating microfiltration on easily scale-forming inorganic ions: Through TMF physical interception and multi-nuclear chemical agents, fluoride ions and silicates, which pose a great threat of fouling, are directly stripped below the safe tolerance limit of the reverse osmosis membrane (silicon content drops to an astonishing 2 mg / L), completely eliminating the risk of membrane fouling.

[0042] Table 3. Comparison Matrix of Macroeconomic Benefits and Comprehensive Process Removal Rate of the Entire System: Conclusion: By directly eliminating high-energy-consuming ammonia removal, pre-pressure controlled acidification adsorption and recovery of phenols under heat / alkali action, coupled with TMF fluoride removal and end-of-pipe triple-effect evaporation to extract compound fertilizer, this invention perfectly solves the global environmental problems of utilizing phenols in high-concentration wastewater, extending RO membrane life, and converting high-risk mixed salts into commercial fertilizers. It significantly reduces the cost per ton of water treatment (20-40 RMB / ton) and establishes a very high technical barrier in terms of ecological benefits and economic operating costs.

[0043] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0044] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater, characterized in that: The system includes a forced air pressure acidification and phenol recovery module, a purification and solid-liquid separation module, a gradient desalination and ultra-high pressure concentration module, and a reduced pressure evaporation and fertilizer extraction module connected in sequence. The forced air pressure acidification and phenol recovery module includes an acidification reactor (1) for receiving coking / semi-coke wastewater. The acidification reactor (1) is connected to an adsorption column group (2). The adsorption column group (2) is connected to the purification and solid-liquid separation module. The purification and solid-liquid separation module includes a pretreatment tank (3) connected to the adsorption column group (2). The pretreatment tank (3) is connected to a TMF microfiltration unit (4). The TMF microfiltration unit (4) is connected to the gradient desalination and ultra-high pressure concentration module. The reduced pressure evaporation and fertilizer extraction module is used to produce compound fertilizer.

2. The novel process system for the complete resource utilization of phenol and ammonia in coking and semi-coke wastewater according to claim 1, characterized in that: The top of the acidification reactor (1) is provided with an H2SO4 dosing pipeline. The acidification reactor (1) is provided with a high-pressure liquid distributor and a first stirring mechanism. The bottom water outlet pipeline of the acidification reactor (1) is connected to the adsorption column group (2) in series through a high-pressure chemical shielded pump.

3. The novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater according to claim 1, characterized in that: The adsorption column group (2) is equipped with special adsorption materials for the synthesis of phenol molecules. The side end of the adsorption column group (2) is connected to a steam / alkali washing desorption pipeline. The desorption outlet of the adsorption column group (2) is connected to a high-purity phenol recovery pipeline. The main water outlet of the adsorption column group (2) is connected to the pretreatment tank (3).

4. The novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater according to claim 1, characterized in that: The top of the pretreatment tank (3) is provided with a dosing mechanism for adding multi-nucleus desiliconization agent, and the pretreatment tank (3) is provided with a second stirring mechanism.

5. The novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater according to claim 1, characterized in that: The pretreatment tank (3) is connected to the inlet manifold of the TMF microfilter (4) via a water supply circulation pump, and the bottom of the TMF microfilter (4) is connected to a plate and frame filter press (5).

6. The novel process system for the complete resource utilization of phenol and ammonia in coking and semi-coke wastewater according to claim 1, characterized in that: The gradient desalination and ultra-high pressure concentration module includes a UF+RO staged membrane (6), which is connected to the TMF microfiltration (4). The desalinated soft water produced by the UF+RO staged membrane (6) is directly led out of the system, and the concentrated water with a salt content of 10-20% produced by the UF+RO staged membrane (6) is transported to the DTRO ultra-high pressure concentration module (7) through a high pressure pipeline.

7. The novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater according to claim 6, characterized in that: The DTRO ultra-high pressure concentration module (7) is made of alternating stacked guide plates and reverse osmosis membrane bags. The guide plates are provided with multiple logarithmically spirally arranged guide columns. The DTRO ultra-high pressure concentration module (7) is connected to the reduced pressure evaporation and fertilizer extraction module.

8. The novel process system for the complete resource utilization of phenol and ammonia in coking and semi-coke wastewater according to claim 7, characterized in that: The reduced pressure evaporation and fertilizer extraction module includes a reduced pressure triple-effect evaporation system (8) connected to the DTRO ultra-high pressure concentration component (7). The reduced pressure triple-effect evaporation system (8) includes a first-effect evaporator, a second-effect evaporator and a third-effect evaporator connected in series. The third-effect evaporator is connected to a crystallization separation centrifuge (9).

9. The novel process system for the complete resource utilization of phenol and ammonia in coking and semi-coke wastewater according to claim 8, characterized in that: The reduced pressure triple-effect evaporation system (8) is used to receive the 25% concentrated mother liquor produced by the DTRO ultra-high pressure concentration component (7).

10. A novel process for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater, based on the novel process system for the complete resource utilization of phenols and ammonia in coking and semi-coke wastewater as described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Pre-forced pressure acidification and limited directional adsorption and recovery of phenols: The original wastewater containing high concentrations of free ammonia and phenols is introduced into the acidification reactor (1) to adjust the pH value in the acidification reactor (1) and stabilize it in the acidic range. S2, Multi-core agent complexation for fluoride and silicon removal and TMF fluid circulation microfiltration, the wastewater treated in step S1 enters the pretreatment tank (3), and multi-core composite agent is added to the pretreatment tank (3) for fluoride and silicon removal; S3. The whole membrane method graded gradient desalination and ultra-high pressure DTRO concentration are used to send the purified water into the UF+RO graded composite membrane. The desalinated soft water produced is directly reused in the plant production, and the remaining concentrated water is sent into the DTRO ultra-high pressure concentration module (7) for further treatment. S4. Gradient depressurization triple-effect evaporation crystallization and fertilizer production: 25% concentration mother liquor is directly pumped into the depressurization triple-effect evaporation system (8), and the produced high-purity fertilizer is separated by two-stage centrifugation in the crystallization separation centrifuge (9) and packaged for shipment.

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