CN-121990720-A - Ammonia nitrogen wastewater treatment cooperated with carbon dioxide fixation process system

CN121990720ACN 121990720 ACN121990720 ACN 121990720ACN-121990720-A

Abstract

The invention discloses a cooperative carbon dioxide fixation process system for ammonia nitrogen wastewater treatment, and relates to the technical field of ammonia nitrogen wastewater treatment. The system comprises a water inlet pretreatment unit, an ammonia nitrogen adsorption unit, a carbon dioxide nanocrystallization unit, a filler regeneration unit, a product conversion unit and a full-flow cooperative control unit, wherein a closed loop process system of water inlet pretreatment, ammonia nitrogen adsorption, carbon dioxide nanocrystallization, filler regeneration and product conversion is constructed, a ZSM-5 molecular sieve is used as an adsorption medium, a carbon dioxide nanobubble mixed solution is used as a regeneration medium, deep coupling of ammonia nitrogen wastewater purification, carbon dioxide fixation and ammonium bicarbonate recycling is realized, benign circulation of pollution control, carbon fixation and recycling is formed, a design and guarantee process is continuously developed by means of alternate operation of double adsorption tanks, and the technical problem of secondary pollution generated by a traditional acid-base regeneration method is solved, and the stability and environmental friendliness of ammonia nitrogen wastewater treatment are improved.

Inventors

DING YALEI
YUAN MENGYUAN
FENG SHUHUA

Assignees

杭州拓水环保科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260306

Claims (10)

1. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system is characterized by comprising a water inlet pretreatment unit, an ammonia nitrogen adsorption unit, a carbon dioxide nanocrystallization unit, a filler regeneration unit, a product conversion unit and a full-flow cooperative control unit; Each unit forms a closed-loop process system through a fluid conveying pipeline and a control valve, and a multi-parameter coupling algorithm and a material balance model are built in the whole-flow cooperative control unit to dynamically adjust the operation parameters of each unit; the inflow pretreatment unit performs graded purification on the medium-high concentration ammonia nitrogen wastewater to remove suspended matters, colloid and calcium and magnesium ions, and the operation strength of the inflow pretreatment unit is dynamically adjusted along with the adsorption efficiency data of the ammonia nitrogen adsorption unit; The ammonia nitrogen adsorption unit is provided with at least two adsorption tank bodies connected in parallel, ZSM-5 molecular sieve adsorption media are filled in the tank, the pore channel structure of the media and the surface adsorption sites are regulated and controlled to form selective combination with ammonia nitrogen ions in the wastewater, and the two adsorption tank bodies are alternately switched to operate; the carbon dioxide nanocrystallization unit adopts an ultrasonic cavitation and high-speed shearing composite process, breaks carbon dioxide gas into nanoscale bubbles and mixes the nanoscale bubbles with water to form a regeneration liquid raw material, and the preparation amount of the regeneration liquid raw material is quantitatively set according to the ammonia nitrogen adsorption total amount of the ammonia nitrogen adsorption unit; The filler regeneration unit takes carbon dioxide nano-bubble mixed liquid as a regeneration medium to replace the traditional acid-base regenerant, ion exchange occurs in the contact process of the regeneration liquid and the adsorption medium, ammonia nitrogen ions are separated from the adsorption medium, carbon dioxide and the ammonia nitrogen ions are chemically combined, and the flow and the temperature of the regeneration liquid are set according to the ammonia nitrogen load of the adsorption tank body; The product conversion unit receives the regeneration liquid containing high-concentration ammonia nitrogen ions and dissolved carbon dioxide and performs conversion treatment to obtain ammonium bicarbonate solid, and mother liquor and escaping gas in the conversion process flow back to the front-end unit; the full-flow cooperative control unit collects parameters such as ammonia nitrogen concentration, carbon dioxide consumption, regeneration liquid reaction state, product purity and the like of each unit in real time, and adjusts operation parameters of each unit through a multi-objective optimization algorithm to realize dynamic matching of ammonia nitrogen removal, carbon dioxide combination and product conversion.
2. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system according to claim 1, wherein the inlet water pretreatment unit sequentially performs grille filtering, composite coagulation clarification and ion exchange pretreatment procedures, and operation parameters of each procedure are adjusted in bidirectional association with operation data of the ammonia nitrogen adsorption unit; The ion exchange pretreatment process adopts calcium-magnesium specific exchange resin, the resin and calcium-magnesium ions in the wastewater undergo an exchange reaction, the binding competition of the calcium-magnesium ions and ammonia nitrogen ions on the surface of an adsorption medium is reduced, the adsorption medium blockage caused by precipitation generation is reduced, and the regeneration frequency of the exchange resin is dynamically adjusted along with the running resistance data of an ammonia nitrogen adsorption unit; Adding a special compound coagulant for ammonia nitrogen in the compound coagulation and clarification process, forming a flocculating constituent by the coagulant, colloidal impurities and partial organic pollutants in the wastewater, and feeding back and adjusting the addition amount of the coagulant according to the content of suspended matters in the inlet water and the adsorption efficiency data of an ammonia nitrogen adsorption unit; the grid filtering procedure removes large particle suspended matters and floaters in the wastewater, the filtering precision is set according to the pore canal size of the subsequent adsorption medium, and the blockage of impurities to the pore canal of the adsorption medium is reduced.
3. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system is characterized in that the pore channel size of an adsorption medium of the ammonia nitrogen adsorption unit is regulated and controlled to be matched with the diffusion characteristic of ammonia nitrogen ions, and the binding capacity of the adsorption sites with the ammonia nitrogen ions is enhanced after the surface adsorption sites are subjected to activation treatment; When the ammonia nitrogen concentration of the effluent of one adsorption tank body reaches a set value, the full-flow cooperative control unit triggers a switching instruction, stops water inflow of the tank body and starts a regeneration flow, and simultaneously starts the other adsorption tank body, so that the treatment process is continuously carried out; The waste water flow path of the adsorption tank body and the contact path of the subsequent regeneration liquid are reversely arranged, so that the contact area of the adsorption medium, the waste water and the regeneration liquid is increased.
4. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system is characterized in that the carbon dioxide nanocrystallization unit sequentially performs carbon dioxide gas purification, nanobubble generation and mixed liquid constant-temperature storage procedures, and operation parameters of each procedure are related to a filler regeneration unit through stoichiometric ratios; The carbon dioxide gas purification process adopts an active carbon and molecular sieve composite adsorption medium to remove moisture, sulfide and dust impurities in the carbon dioxide gas in the industrial tail gas capture, so that the purity of the carbon dioxide gas is improved, and the requirement of the regeneration reaction on the content of the gas impurities is met; The specific surface area and stability of the nano bubbles prepared in the nano bubble generation process are improved, the solubility and the reactivity of carbon dioxide in water are improved, and the generation parameters are matched with the ion exchange reaction parameters of the filler regeneration unit; The mixed liquid constant temperature storage procedure keeps the regenerated liquid in a set temperature range, nano bubble aggregation is reduced by continuous stirring, and the storage temperature is matched with the ion exchange activity parameter of the adsorption medium.
5. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system according to claim 4, wherein the contact time of the regenerated liquid of the filler regeneration unit and the adsorption medium is set in a region where ammonia nitrogen ions are completely separated from carbon dioxide, the release rate of carbon dioxide nanobubbles is synchronous with the separation rate of ammonia nitrogen ions, and the conditions that the concentration of carbon dioxide in a local area is too high or ammonia nitrogen is not completely separated from the adsorption medium are reduced; The trace gas generated in the regeneration process is led into a gas purification component through a collecting pipeline, and after ammonia components are removed through an acid adsorption medium, unreacted carbon dioxide is refluxed to a carbon dioxide nanocrystallization unit again; The filler regeneration unit is provided with a regeneration liquid circulation purification process, and a filter medium is adopted to intercept molecular sieve fragments and tiny impurities carried in the regeneration liquid, so that the influence of impurity accumulation on the regeneration reaction and pipeline circulation is reduced.
6. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system according to claim 5, wherein the recycled and purified regenerated liquid is partially returned to the carbon dioxide nanocrystallization unit, the rest is conveyed to the product conversion unit, and the reflux ratio is dynamically adjusted according to the reaction state of the regenerated liquid; The carbon dioxide concentration of the reflux regeneration liquid is monitored in real time by a full-flow cooperative control unit, and fresh carbon dioxide nanobubble mixed liquid is supplemented according to concentration change, so that the reaction activity of the regeneration liquid is kept in a set interval; the ratio of the circulating flow of the regeneration liquid to the fresh supplementing amount is set according to the ammonia nitrogen eluting requirement of the ammonia nitrogen adsorption unit and the combination target of carbon dioxide.
7. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system is characterized in that the product conversion unit sequentially executes pH gradient adjustment, ultrasonic crystallization induction and solid-liquid separation purification procedures, and the operation parameters of each procedure are adjusted in a correlated way with a front-end unit through product purity data; the ultrasonic crystallization induction process adopts a composite technology of ultrasonic induction and low-temperature regulation, ultrasonic parameters are dynamically adjusted along with the concentration of the regenerated liquid, the growth state of ammonium bicarbonate crystals is promoted to be uniform, and a temperature interval of low-temperature regulation is matched with the parameters of crystal purity and growth rate; The solid-liquid separation and purification process adopts a high-efficiency filtration and centrifugal separation composite process, separated solid particles are subjected to low-temperature drying treatment to obtain ammonium bicarbonate solid meeting the agricultural use standard, and separated mother liquor flows back to the filler regeneration unit.
8. The ammonia nitrogen wastewater treatment synergistic carbon dioxide fixation process system as claimed in claim 7, wherein the weakly alkaline regulating solution is food-grade sodium bicarbonate solution, and the addition amount is calculated and determined by a full-flow synergistic control unit according to the ammonia nitrogen concentration and the carbon dioxide content in the regenerated solution; a small amount of carbon dioxide gas dissipated in the crystallization induction procedure is led into a carbon dioxide nanocrystallization unit through a recovery pipeline, and the carbon dioxide which is not dissipated is participated in the process cycle again; The product conversion unit and the filler regeneration unit form feedback through the quality data of the regeneration liquid, when the ammonia nitrogen concentration in the regeneration liquid is detected to be lower than a set value, the full-flow cooperative control unit increases the supplementing amount of the fresh carbon dioxide nanobubble mixed liquid, and simultaneously adjusts the regeneration time length of the adsorption tank body.
9. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system according to claim 1, wherein the multiparameter coupling algorithm of the full-flow cooperative control unit establishes quantitative association of key parameters of each unit based on stoichiometric ratio of ammonia nitrogen and carbon dioxide to ammonium bicarbonate; The association relation comprises a corresponding relation between the ion removal rate of the inlet water pretreatment unit and the adsorption selectivity of the ammonia nitrogen adsorption unit, a corresponding relation between the ammonia nitrogen load of the ammonia nitrogen adsorption unit and the carbon dioxide supply amount of the filler regeneration unit, a corresponding relation between the reaction state of the regeneration liquid of the filler regeneration unit and the crystallization efficiency of the product conversion unit, and a corresponding relation between the product purity of the product conversion unit and the recycling ratio; The full-flow cooperative control unit receives sensing data of each unit in real time, and adjusts coagulant addition amount of water inlet pretreatment, wastewater retention time of ammonia nitrogen adsorption, carbon dioxide supply rate of filler regeneration and pH adjustment rhythm of product conversion, so that running parameters of each unit are dynamically matched.
10. The ammonia nitrogen wastewater treatment and carbon dioxide fixation process system according to claim 3, wherein the adsorption medium of the ammonia nitrogen adsorption unit is used for evaluating adsorption performance through periodic sampling detection, and when the adsorption capacity is reduced to a set value, a regeneration strengthening process or medium supplementing operation is performed to keep the adsorption performance of the adsorption medium at a set level; The whole-flow cooperative control unit presets an abnormal working condition coping strategy, when the water quality of the water inlet pretreatment unit exceeds a set standard, the ammonia nitrogen adsorption unit prolongs the residence time of the wastewater, the filler regeneration unit improves the concentration of the regenerated liquid, and the product conversion unit delays the reflux of the mother liquid until the pretreated water quality is recovered to a set range; When the carbon dioxide supply amount of the filler regeneration unit is insufficient, the ammonia nitrogen adsorption unit reduces the water inflow rate, the product conversion unit reduces the pH adjustment rate, and the gas recovery unit increases the recovery amount of the dissipated carbon dioxide, so that the combination amount of the carbon dioxide and the purity of the product are kept in a set range.

Description

Ammonia nitrogen wastewater treatment cooperated with carbon dioxide fixation process system Technical Field The invention relates to the technical field of ammonia nitrogen wastewater treatment, in particular to an ammonia nitrogen wastewater treatment and carbon dioxide fixation process system. Background Excessive emissions of carbon dioxide cause global warming, causing a series of serious environmental problems such as glacier melting, rising sea level, and increased extreme climate events. Thus, the fixation or synthesis of captured carbon dioxide into valuable products is of great importance for alleviating greenhouse effect, promoting benign development of carbon circulation, and achieving sustainable development goals. Meanwhile, the treatment of ammonia nitrogen wastewater is also an important problem to be solved urgently in the current environmental protection field. The ammonia nitrogen wastewater has wide sources, covers industrial production processes such as chemical industry, pharmacy, chemical fertilizer, coking and the like, and wastewater entering a water body along with rainwater runoff after excessive use of nitrogen fertilizer and organic fertilizer in agricultural production, also excrement and flushing wastewater of livestock and poultry farms, and even domestic sewage also contains a certain amount of ammonia nitrogen. If the wastewater is directly discharged without effective treatment, ammonia nitrogen wastewater can cause various serious damages to the ecological environment. In the water body, ammonia nitrogen can consume a large amount of dissolved oxygen, so that aquatic organisms such as fish and the like die due to anoxic choking, water eutrophication can be initiated, plankton such as algae and the like are promoted to excessively reproduce, and the ecological balance of the water body is further destroyed. In the aspect of soil, after the ammonia nitrogen wastewater permeates the soil, the physicochemical property of the soil can be changed, the activity of soil microorganisms can be inhibited, the soil fertility can be reduced, and the growth and the yield of crops can be influenced. From the perspective of an ecological system, the emission of ammonia nitrogen wastewater seriously damages the stability of the ecological system and threatens the biodiversity. From the standpoint of human health, after the improperly treated ammonia nitrogen wastewater enters a drinking water source, ammonia nitrogen can be converted into nitrite, and the nitrite combines with protein in a human body to generate strong cancerogenic substance nitrosamine, so that the human health is seriously endangered. Traditional ammonia nitrogen wastewater treatment mainly depends on a biodegradation technology, however, the technology has a plurality of limitations. For example, biological nitrification and denitrification processes require long hydraulic residence times, and often require additional carbon sources to meet reaction requirements during the denitrification stage, which undoubtedly increases carbon dioxide emissions and operational complexity. Meanwhile, biological methods are sensitive to reaction conditions, and small changes of environmental factors such as temperature, pH value and the like can obviously influence the activity of microorganisms. Under the low-temperature environment, the enzymatic reaction rate of microorganisms is greatly reduced, the activities of nitrifying bacteria and denitrifying bacteria are obviously inhibited, and even the phenomenon of stagnation of vital activities is possible to occur, so that the treatment effect of ammonia nitrogen wastewater is greatly reduced. Disclosure of Invention In order to solve the technical problems in the prior art, the embodiment of the invention provides a process system for treating ammonia nitrogen wastewater and fixing carbon dioxide in a cooperated manner. The technical scheme is as follows: On one hand, the invention provides a synergistic carbon dioxide fixation process system for ammonia nitrogen wastewater treatment, which comprises a water inlet pretreatment unit, an ammonia nitrogen adsorption unit, a carbon dioxide nanocrystallization unit, a filler regeneration unit, a product conversion unit and a full-flow synergistic control unit; Each unit forms a closed-loop process system through a fluid conveying pipeline and a control valve, and a multi-parameter coupling algorithm and a material balance model are built in the whole-flow cooperative control unit to dynamically adjust the operation parameters of each unit; the inflow pretreatment unit performs graded purification on the medium-high concentration ammonia nitrogen wastewater to remove suspended matters, colloid and calcium and magnesium ions, and the operation strength of the inflow pretreatment unit is dynamically adjusted along with the adsorption efficiency data of the ammonia nitrogen adsorption unit; The ammonia nitrogen adsorption unit is provided wit