CN107758916B

CN107758916B - Modularized integrated process method suitable for mine acidic wastewater treatment

Info

Publication number: CN107758916B
Application number: CN201710821732.0A
Authority: CN
Inventors: 何亚婷
Original assignee: 徐磊
Current assignee: Xu Lei
Priority date: 2017-11-03
Filing date: 2017-11-03
Publication date: 2020-11-20
Anticipated expiration: 2037-11-03
Also published as: CN107758916A

Abstract

The invention relates to a modular integrated process method suitable for mine acid wastewater treatment, which is characterized by comprising the following steps of: aiming at high-concentration mine acid wastewater, process integration and parametric design are carried out, and the system is composed of 4 modules: the system comprises a primary pretreatment module, a secondary physicochemical module, a tertiary chemical module and a quaternary advanced treatment module, wherein the primary pretreatment module is provided with a grid screen and a regulating water tank to remove suspended matters and regulate water quantity; the secondary materialization module is provided with a diffusion dialyzer and an PZX reactor for recycling waste acid and removing heavy metal ions; the third-stage chemical module is provided with a mixing reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary reaction tank, and residual heavy metal ions are removed; the four-stage advanced treatment module is provided with an active sand filter and an active carbon adsorption tank to remove SS and chromaticity. And selecting different units to operate according to the water quality condition of the inlet water. The process has the characteristics of flexibility, high efficiency, convenience, intelligence and the like, and can ensure economic, effective and stable operation of wastewater treatment facilities.

Description

Modularized integrated process method suitable for mine acidic wastewater treatment

Technical Field

The invention relates to an integrated treatment technology of high-concentration organic wastewater, in particular to a modularized integrated process suitable for mine acidic wastewater treatment, which is used for realizing process modularization, intellectualization and integration by carrying out process integration and parametric design aiming at the problem of high-concentration wastewater treatment generated in the mining process of mine enterprises.

Background

Mineral resources play a very important role in the process of continuously increasing national economy, continuously developing society forward and continuously improving the living standard of people. However, the serious set of mine environmental problems induced by the long term unjustified exploitation of mineral resources disorder does not appear to be of great value. Acid mine wastewater is one of the acid mine wastewater. The acidic mine wastewater has a great influence on the environment due to the fact that the acidic mine wastewater has great acidity and also contains heavy metal ions such as copper, lead, zinc, cadmium and the like. Once the wastewater directly flows into the natural water system and then flows into the regional water system, great influence and harm are caused to the living, production and ecological environment of downstream residents. Mine acid wastewater has been identified as one of the most prominent environmental problems facing the mining industry today.

According to incomplete statistics, in 2007, the total production of 10 nonferrous metals by nonferrous metal enterprises in China totals 2360.52 ten thousand tons. In the whole production process from mining, ore dressing to smelting and finished product processing in the nonferrous metal industry, almost all working procedures need water, and wastewater is discharged. According to different sources, products and processing objects of the waste water, the waste water can be divided into mining waste water, mineral processing waste water, smelting waste water and processing waste water. The smelting waste water can be divided into heavy non-ferrous metal smelting waste water, light non-ferrous metal smelting waste water and rare non-ferrous metal smelting waste water. The non-ferrous metal smelting waste water can be divided into acid waste water, alkaline waste water, heavy metal waste water, cyanide-containing waste water, fluorine-containing waste water, oil-containing waste water, radioactive waste water and the like according to the main components of pollutants contained in the waste water. The pollution caused by the non-ferrous metal industrial wastewater mainly comprises inorganic suspended solid pollution, organic oxygen consuming substance pollution, heavy metal pollution, petroleum pollution, alcohol pollution, alkali pollution, heat pollution and the like.

During mining, a large amount of mine wastewater can be generated, including pit water, waste rock site leaching water, mineral processing wastewater, tailing pond wastewater and the like. Among them, the most important and most influential liquid wastes are derived from mine acid wastewater. The acid mine wastewater is mainly generated in waste rock storage yards and mine pits. The quality of the acid wastewater in the waste rock storage yard is influenced by the components of the waste rocks, the geometric shape of the waste rock storage yard, the rainfall intensity and duration, the air temperature, microorganisms and other factors; the quality and quantity of the acid waste water in the mine pit are different according to the geographical position, elevation, surrounding rock structure, mining operation method, precipitation and the like of the mine pit. The acid mine wastewater has the following characteristics: contains various metal ions, and the pH value is more than 2.5-4.5; large amount of waste water and long water flow time; and thirdly, the drainage points are dispersed, and the fluctuation of water quality and water quantity is large.

The untreated acid mine wastewater is directly discharged, which can cause water pollution. Firstly, the wastewater has extremely high acidity, which can corrode pipelines and equipment, reduce the service life of the wastewater, increase the maintenance cost and improve the production cost. Heavy metal ions in water poison fishes, plankton, algae, etc. and die in large quantities. Fe in water²⁺By oxidation to Fe³⁺，Fe³⁺Bound OH^－Production of Fe (OH)₃The reddish brown precipitates, so that the bottom and two banks of the water body are red, and the attractiveness is affected. In addition, the human body can corrode the skin after contacting acid mine and mountain water for a long time, so that hands and feet are cracked, and the health of the human body is influenced. Untreated acid mine wastewater enters surface water after being discharged, and when the water is used for irrigating farmlands, the soil structure can be damaged, so that the soil is hardened, the growth of crops is inhibited, and the crops die in a large area in severe cases, so that the yield of grains is reduced.

At present, the acid mine water treatment methods at home and abroad mainly comprise chemical treatment, physical treatment, biological treatment and the like, wherein the most common process methods mainly comprise a neutralization method, a microbiological method, an artificial wetland method, a membrane method and the like.

The neutralization method is the most common treatment method, and the method is to add a neutralizing agent into the wastewater to ensure that heavy metal ions in the wastewater generate hydroxide precipitates to be separated from water, so that the wastewater reaches the discharge standard. Generally, limestone or lime is used as a neutralizing agent for neutralization. However, the neutralization method has the problems that the neutralization method needs to add a large amount of neutralizing agent, not only has high operation cost, but also generates a large amount of toxic waste residues, has high treatment difficulty and high cost of the waste residues and is easy to generate secondary pollution, and causes pipelines and equipment to be easy to scale and shorten the operation life.

The microbiological method is the most common water treatment method for domestic sewage, but because the requirements of microorganisms on conditions such as pH value, temperature and the like are high, the method for treating mine acidic wastewater by using microorganisms is still in a laboratory research stage and is not widely applied.

The constructed wetland system has the advantages of low construction cost and operation cost, low energy consumption, simple operation, strong adaptability and the like. It also has the function of beautifying the environment if proper plant varieties are selected. However, the acid mine wastewater contains a large amount of heavy metal elements and has a low pH value, so that the acid mine wastewater has a large influence on plant growth, and the artificial wetland system has the problems of large floor area, large environmental influence, high wetland maintenance cost and the like, so that the acid mine wastewater is limited in application in acid mine wastewater treatment.

The membrane separation technology has been widely researched and explored in the field of industrial wastewater treatment as a high and new technology, and has considerable technical advantages in the field of water treatment due to the characteristics of high separation efficiency, no phase change, energy conservation, environmental protection, simple equipment, simple and convenient operation and the like, so that the membrane separation technology becomes one of indispensable technologies in the field of water treatment. However, heavy metal ions contained in the non-pretreated acid mine wastewater accelerate the consumption of the membrane, shorten the service life of the membrane and greatly increase the water treatment cost.

In conclusion, the acid mine wastewater contains a large amount of heavy metal ions and sulfate ions due to the special water quality characteristics, has poor biodegradability and is not easy to degrade, and no particularly effective treatment method is available in China, so that the method is efficient, cheap, safe and simple to operate. In addition, the acid mine wastewater contains recoverable acids, and the current treatment methods cannot recover part of the acid resources.

In order to solve the problems, the invention provides an effective treatment method for acid mine wastewater. The invention aims to adopt a physical and chemical method to treat the wastewater, and because a single physical process and a single chemical process can not realize the efficient removal of high-concentration organic matters in the production wastewater, the process provided by the invention organically combines the physical process and the chemical process and operates together.

Disclosure of Invention

The invention particularly relates to a modularized integrated process method suitable for mine acid wastewater treatment, which aims at the problem of high-concentration wastewater treatment generated in the production process of mines and is used for carrying out process integration and parametric design to realize process modularization, intellectualization and integration.

According to the characteristics of the production wastewater and the requirements of the wastewater treatment process, and the principles of mature and reliable technology, stable operation, convenient maintenance and management, economy and applicability are carried out, the mine acidic wastewater treatment process is optimized and integrated, and a set of operation method suitable for different water qualities is developed.

The invention relates to an integrated technical method of mine acid wastewater, which consists of 4 modules, and the modules are respectively named as a primary pretreatment module, a secondary materialization module, a tertiary chemical module and a quaternary advanced treatment module.

The primary pretreatment module comprises a grid screen and a regulating water tank. Setting a grid screen with 10 meshes to remove suspended matters in water so as to ensure the normal operation of subsequent treatment facilities; and a regulating water tank is arranged for regulating the water quantity, so that the water inflow of subsequent treatment facilities is stable, and the hydraulic retention time is 12.0-24.0 h.

The secondary materialization module comprises a diffusion dialyzer and an PZX reactor (expanded vermiculite ion exchange adsorption reactor). The diffusion dialyzer intermittently operates according to water quality indexes to monitor the pH value of inlet water as a control index: when the pH value is less than 4.0, the diffusion dialyzer is operated to realize the recovery of waste acid and reduce the acid load for subsequent treatment facilities; when the pH value is more than or equal to 4.0, the wastewater surpasses a diffusion dialyzer and directly enters an PZX reactor, and a PZX reactor continuously operates.

The diffusion dialyzer takes concentration difference as driving force, the whole device is formed by combining a diffusion dialysis membrane, a liquid distribution plate, a reinforcing plate, a liquid flow plate frame and the like, and a certain number of membranes form different numbers of structural units; wherein each unit is divided into a dialysis chamber (A) and a diffusion chamber (B) by an anion homogeneous membrane, and when waste acid liquid and receiving liquid (pure water or tap water) are respectively introduced into two sides of the anion homogeneous membrane, the concentration of free acid and salt thereof on the waste acid liquid side is far higher than that on the water side. Due to the concentration gradient, the free acid and its salts in the spent acid tend to permeate the B compartment, but the membrane is selectively permeable, not allowing every ion to pass through with equal opportunity. Firstly, the anion membrane skeleton is positively charged, and has the characteristic of attracting negatively charged hydrated ions and repelling positively charged hydrated ions in the solution, so under the action of concentration difference, anions on the waste acid side are attracted and smoothly permeate through the membrane pore channels to enter one side of water. Meanwhile, ions with positive charges can be carried in the solution according to the requirement of electric neutrality, and the hydration radius of H + is smaller, so that the charge is less; the hydrated ionic radius of the metal salt is larger and the metal salt is expensive, so that H + can preferentially pass through the membrane, and the acid in the wastewater can be separated.

The PZX reactor is named as an expanded vermiculite ion exchange adsorption reactor, is an ion exchange adsorption reactor filled with expanded vermiculite, and adopts finished product PZX packing as a main reaction unit. The finished product PZX filler comprises an outer frame, a filler and a reinforcing agent, and the specific method comprises the following steps: the outer frame is a finished polyether polyester shell, the outer frame is rectangular, the length and the width of the outer frame are consistent with the length and the width of equipment, the height of the outer frame is 1.0-1.5 m according to a design value, the rectangular surface of the outer frame is a net shape, polyether polyester is processed into fiber yarns through extrusion spinning, the fiber yarns are overlapped, stacked, knotted and cooled in a die, and the size of a mesh is 5 mm. And filling expanded vermiculite into the finished polyether polyester shell, wherein the diameter of the expanded vermiculite is 7 +/-1 mm. And after filling, soaking the whole body in a reinforcing agent, wherein the reinforcing agent is a mixed solution of carbon powder and 10% of polytetrafluoroethylene, soaking in the reinforcing agent for 30 minutes, taking out, naturally air-drying for 3 hours, soaking again for 15 minutes, naturally air-drying for 3 hours, soaking again for 5 minutes, and naturally air-drying for 24 hours for later use. The formed finished PZX packing was placed directly into the PZX reactor with a packing layer thickness of 1.0-1.5 m and an equipment design upflow velocity of 15-20 m/h. Besides the filler, the PZX reactor also comprises a water distribution system, a water inlet pipe, a water outlet pipe and an overflow pipe which are arranged at the bottom.

The three-stage chemical module comprises a mixing reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary sedimentation tank.

And (3) continuously operating the mixing reaction tank, adding lime, poly 4-vinylpyridine, dimethylaminoethyl methacrylate, sodium polyacrylate and polyethyleneimine into the tank, and neutralizing and precipitating redundant metal cations in the wastewater. The lime is used for removing all metal cations and sulfate ions, the poly-4-vinylpyridine is used for promoting Cr and Cd ions in the wastewater to be precipitated in an accelerated mode, the polydimethylaminoethyl methacrylate is used for promoting As ions in the wastewater to be precipitated in an accelerated mode, the sodium polyacrylate is used for promoting Pb and Zn ions in the wastewater to be precipitated in an accelerated mode, and the polyethyleneimine is used for regulating the pH value to be alkaline in an accelerated mode. The reaction tank is designed to stay for 30min, and is made of glass fiber reinforced plastic anticorrosive material, and an acid-resistant stirrer is arranged inside the reaction tank. Adding lime, poly 4-vinylpyridine, poly dimethylaminoethyl methacrylate, sodium polyacrylate and polyethyleneimine according to the mass ratio of 1:0.01:0.005:0.02:0.05, wherein the adding amount of lime is determined according to the pH value in the mixing reaction tank, namely when the pH value is less than 8.5, the lime is continuously added, the adding mass concentration is 30-35 mg/L, and when the pH value is more than or equal to 8.5, the adding is stopped.

And the primary sedimentation tank continuously operates, and a horizontal sedimentation tank is adopted to carry out solid-liquid separation on the sediments generated in the mixed reaction tank. The reaction tank is designed to stay for 3 hours, and an electric mud scraping and sucking machine is arranged inside the reaction tank.

The coagulation reaction tank intermittently operates, the numerical value of the water quality of metal ions entering the water is monitored, when the concentration of the heavy metal ions exceeds the standard, namely when Cr is more than 0.5mg/L, Cu is more than 1.0mg/L, Pb is more than 1.0mg/L, Zn is more than 4.0mg/L, Cd is more than 0.1mg/L or As is more than 0.5mg/L, the coagulation reaction tank is operated, polyaluminium chloride is added, the reaction tank is designed to stay for 30min, and an acid-resistant stirrer is arranged inside the reaction tank.

And the secondary sedimentation tank runs intermittently and is synchronous with the coagulation reaction tank, and solid-liquid separation is carried out on sediments generated by the coagulation reaction tank. The reaction tank is designed to stay for 2.5h, and an electric sludge scraping and sucking machine is arranged inside the reaction tank.

The four-stage advanced treatment module comprises an active sand filter and an active carbon adsorption tank which are connected in series.

The activated sand filter further realizes mud-water separation of the precipitated sewage, and ensures that the effluent SS reaches the standard. And determining the running state according to whether the SS value of the inlet water reaches the standard, namely starting running when the SS is more than 100 mg/L. The average filtration rate was designed to be 6 m/h.

The activated carbon adsorption tank is a water treatment method for removing pollutants in water by utilizing the physical adsorption, chemical adsorption, oxidation, catalytic oxidation, reduction and other properties of activated carbon, and is one of the main methods for removing chromaticity at present. Because the mine wastewater contains a large amount of Fe³⁺Ions, and thus color may be in the discharged wastewater to cause sensory discomfort, and therefore, an activated carbon adsorption unit is provided as a chromaticity index in the quality of the influent water>And when the flow rate is 50 ℃, starting the activated carbon adsorption tank, and designing the downward flow velocity to be 5-7 m/h.

The invention relates to an integrated technical method of mine acid wastewater, which consists of 4 modules, and the modules are respectively named as a primary pretreatment module, a secondary materialization module, a tertiary chemical module and a quaternary advanced treatment module. In actual operation, an on-line monitoring system is arranged at the water inlet end, the result is output to the automatic control system through collecting and analyzing the water quality information of the incoming raw water, and the automatic control system sends a signal to the sub-module unit so as to control the automatic operation of the whole process.

The primary pretreatment module comprises a grille screen and an adjusting water tank, wherein the inlet of the grille screen is connected with the acid mine wastewater inlet, and the outlet of the grille screen is connected with the inlet of the adjusting water tank; the outlet of the regulating water tank is connected with the inlet of the secondary materialization module;

the secondary materialization module comprises a diffusion dialyzer and an PZX reactor, wherein the inlet of the diffusion dialyzer is connected with the outlet of the primary pretreatment module, and the outlet of the diffusion dialyzer is connected with the PZX reactor; the outlet of the PZX reactor is connected with the inlet of the tertiary chemical module;

furthermore, an electric valve is arranged in front of an inlet of the diffusion dialyzer and is opened and closed according to process control operation; the inlet of the electric valve is connected with the outlet of the primary pretreatment module; the outlet is connected with the inlet of the PZX reactor;

the third-stage chemical module comprises a mixed reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary sedimentation tank, wherein the inlet of the mixed reaction tank is connected with the outlet of the secondary physicochemical module, and the outlet of the mixed reaction tank is connected with the primary sedimentation tank; the outlet of the primary sedimentation tank is connected with the coagulation reaction tank; the outlet of the coagulation reaction tank is connected with the secondary sedimentation tank; the outlet of the secondary sedimentation tank is connected with the four-stage advanced treatment module;

furthermore, an electric valve is arranged in front of an inlet of the coagulation reaction tank and is opened and closed according to process control operation; the inlet of the electric valve is connected with the outlet of the primary sedimentation tank; the outlet is connected with the inlet of the four-stage deep processing module;

the four-stage advanced treatment unit comprises an active sand filter and an active carbon adsorption tank, wherein the inlet of the active sand filter is connected with the outlet of the three-stage chemical module, and the outlet of the active sand filter is connected to the active carbon adsorption tank; the activated carbon adsorption tank is connected to the main outlet of the water treatment system;

furthermore, an electric valve is arranged in front of an inlet of the active sand filter tank and is opened and closed according to process control operation; the inlet of the electric valve is connected with the inlet of the active sand filter; the outlet is connected with the outlet of the active sand filter;

furthermore, an electric valve is arranged in front of an inlet of the activated carbon adsorption tank and is opened and closed according to process control operation; the inlet of the electric valve is connected with the inlet of the activated carbon adsorption tank; the outlet is connected with the outlet of the activated carbon adsorption tank.

The invention relates to an integrated process method suitable for acid mine wastewater, which adopts the system and comprises the following steps:

step one, starting and operating a primary pretreatment module, introducing mine acidic wastewater into a grille screen to remove suspended matters, and introducing the wastewater without the suspended matters into a regulating water tank to regulate water quantity;

step two, the pH value of the mine acidic wastewater in the regulating water tank is monitored, analyzed and regulated on line, when the pH value is less than 4.0, the step three is carried out, otherwise, the step four is carried out;

step three, starting and operating the diffusion dialyzer, and recovering acid in the wastewater;

step four, starting PZX reactor to treat waste water;

step five, starting the mixing reaction tank, adding lime, poly-4-vinylpyridine, dimethylaminoethyl methacrylate, sodium polyacrylate and polyethyleneimine, stirring, and monitoring the pH value of the wastewater in the mixing reaction tank on line; stopping adding the medicine when the pH value is 8.5; starting a primary sedimentation tank, and carrying out sedimentation and sludge discharge on the wastewater;

step six, the concentration of the metal ions in the primary sedimentation tank is monitored on line, and when the concentration of the metal ions reaches the effluent standard, namely when Cr is less than 0.5mg/L, Cu and less than 1.0mg/L, Pb and less than 1.0mg/L, Zn and less than 4.0

When the mg/L, Cd is less than 0.1mg/L, As is less than 0.5mg/L, the step eight is carried out, otherwise, the step seven is carried out;

step seven, starting the coagulation reaction tank, adding polyaluminium chloride, stirring, and monitoring the concentration of metal ions in the wastewater of the mixing reaction tank on line; stopping adding the medicine when the standard is reached; starting a secondary sedimentation tank, and carrying out sedimentation and sludge discharge on the wastewater;

step eight, monitoring an SS value of an inlet of the activated sand filter on line, entering the step nine when the SS value is larger than 100, and entering the step ten if not;

step nine, starting the active sand filter to filter the wastewater;

step ten, monitoring the colorimetric value of an inlet of the activated carbon adsorption tank on line, entering the step eleven when the colorimetric value is larger than 50, and otherwise, directly discharging water;

and step eleven, starting the activated carbon adsorption tank to perform adsorption treatment on the wastewater.

The invention relates to a modular integrated process method suitable for mine acid wastewater treatment, which has the following technical characteristics:

1. the method is suitable for treating the wastewater in the acid field of small and scattered mines with strong acidity, high heavy metal ion content, complex components and large fluctuation;

2. the process adopts a plurality of units in series connection, and the conversion process is automatically controlled by changing the operation parameters of the equipment, so that the floor area is saved, and the manufacturing cost is saved;

3. the PZX reactor is adopted in the main treatment process, has good cation exchange performance and adsorptivity, can replace heavy metal cations in the wastewater, reduces the toxicity of the wastewater, and can improve the pH value of the wastewater. And no sludge is produced, the production of high-concentration industrial sludge is reduced, the sludge treatment cost is reduced, and the pollution is reduced;

4. a diffusion dialysis unit is adopted before the main treatment process, and the intermittent operation is carried out according to the quality of the wastewater, so that waste acid can be recovered, the resource utilization rate of wastewater treatment is improved, the wastewater treatment cost is compensated, and the income is generated;

5. the process combination has high modularization degree, is beneficial to the technology to be converted into integrated equipment, and saves space; the process combination technology is advanced and stable and reaches the standard.

Drawings

FIG. 1 is a process scheme of the present invention. FIG. 2 is a block diagram of a computer program according to the present invention. FIG. 3 is a schematic representation of the PZX reactor of the present invention.

1. An online water quality monitoring system; 2. a primary pre-processing module; 3. a secondary materialization module; 4. a third-level chemical module; 5. a four-stage depth processing module; 6. and (3) a computer automatic control system.

a. A grating sieve; b. adjusting the water tank; c. a diffusion dialyzer; a PZX reactor; e, mixing the reaction tank; f, a primary sedimentation tank; g, a coagulation reaction tank; h, a secondary sedimentation tank; i, an active sand filter; j activated carbon adsorption tank

-a process line; -Signal input output

(1) A main tank body of the equipment; (2) a finished packing casing; (3) expanded vermiculite filler; (4) a reinforcing agent; (5) a water inlet and distribution system; (6) a water inlet pipe; (7) a water outlet pipe; (8) overflow pipe

Detailed Description

An on-line monitoring system is arranged at the water inlet end, the result is output to an automatic control system through collecting and analyzing the water quality information of the incoming raw water, and the automatic control system sends signals to the modules or the sub-module units so as to control the automatic operation of the whole process.

The sewage firstly enters a first-stage pretreatment module which comprises 2 units, namely a grid sieve unit and an adjusting water tank unit, wherein the grid sieve unit and the adjusting water tank unit are continuously operated, and the number of grid sieves is 10; and adjusting the water tank unit, wherein the hydraulic retention time is 12.0-24.0 h.

The secondary materialization module comprises a diffusion dialysis unit and an PZX reactor unit which are connected in series for operation. The diffusion dialysis unit runs intermittently, and is started when the pH value of inlet water is less than 4.0, so as to recover waste acid in the waste water; PZX reactor unit, continuously operated, with an upward flow velocity of 15-20 m/h.

And the three-stage chemical module comprises four units, namely a mixing reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary sedimentation tank. The mixing reactor and the primary sedimentation tank continuously run, and the coagulation reaction tank and the secondary sedimentation tank intermittently run, namely, the mixing reactor and the primary sedimentation tank are started to run when the heavy metal ions in the inlet water exceed the standard.

And the four-stage advanced treatment module comprises an active sand filter unit and an active carbon adsorption unit. And the active sand filter unit runs intermittently, starts to run when SS is more than 100mg/L according to the inlet water SS value, and designs the average filtering speed to be 6 m/h. The activated carbon adsorption unit runs intermittently, when the chroma index in the inlet water quality is more than 50, the activated carbon adsorption tank is started, and the downward flow velocity of the activated carbon adsorption tank is 5-7 m/h.

[ example one ]

The quality of the acid wastewater and the inlet and outlet water of a certain mine is shown in Table 1.

TABLE 1 Water quality index of acid wastewater from a certain mine

Item	Unit of	Water inflow index	Index of water discharge	Item	Unit of	Water inflow index	Index of water discharge
								pH value
		2—3	6—9	Cr	mg/L	0.5	0.5
								Cu	mg/L	7.5	1.0	SS	mg/L	50	200
Pb	mg/L	5.3	1.0	SO₄ ^2-	mg/L	5000	—
								Zn	mg/L	100	4.0	Fe²⁺	mg/L	150	—
Cd	mg/L	1.0	0.1	Fe³⁺	mg/L	500	—
								As	mg/L	1.5	0.5

By adopting the process, during operation, the start-up operation unit comprises a first-stage pretreatment unit, a diffusion dialysis unit and an PZX reactor unit of a second-stage materialization unit, a mixed reaction tank and a primary sedimentation tank of a third-stage chemical unit, and an activated carbon adsorption unit of a fourth-stage advanced treatment module. The effluent indexes all meet the design requirements.

[ example two ]

The quality of the acid wastewater and inlet and outlet water of a certain mine is shown in Table 2.

TABLE 2 Water quality index of acid wastewater from a certain mine

By adopting the process, during operation, the start-up operation unit comprises a primary pretreatment unit, an PZX reactor unit of a secondary materialization unit, a mixed reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary sedimentation tank of a tertiary chemical unit, and an active sand filter unit of a four-level advanced treatment module. The effluent indexes all meet the design requirements.

Claims

1. A modular integration method suitable for mine acidic wastewater treatment is characterized by comprising the following steps: the integrated process consists of a primary pretreatment module, a secondary materialization module, a tertiary chemical module and a quaternary advanced treatment module, wherein the primary pretreatment module is mainly provided with a grid screen and a regulating water tank which are arranged in series; the secondary materialization module is mainly provided with a diffusion dialyzer and an PZX reactor which are arranged in series; the three-stage chemical module is mainly provided with a mixing reaction tank, a primary sedimentation tank, a coagulation reaction tank and a secondary reaction tank, and the four units are arranged in series; the four-stage advanced treatment module is mainly provided with an active sand filter and an active carbon adsorption tank which are arranged in series; the module automatically selects different units to operate according to the operating water quality condition;

the PZX reactor is called an expanded vermiculite ion exchange adsorption reactor and consists of an equipment main tank body, finished product PZX filler, a water inlet and distribution system, a water inlet pipe, a water outlet pipe and an overflow pipe; the finished PZX filler comprises an outer frame, a filler and a reinforcing agent, and the specific method comprises the following steps: the outer frame is a finished polyether polyester shell, the outer frame is rectangular, the length and the width of the outer frame are consistent with the length and the width of equipment, the height of the outer frame is 1.0-1.5 m according to a design value, the rectangular surface is a net shape, the polyether polyester is processed into fiber yarns through extrusion spinning, the fiber yarns are overlapped, stacked, knotted and cooled in a die, and the size of a mesh is 5 mm; filling expanded vermiculite into the finished polyether polyester shell, wherein the diameter of the expanded vermiculite is 7 +/-1 mm; and after filling, soaking the whole body in a reinforcing agent, wherein the reinforcing agent is a mixed solution of carbon powder and 10% of polytetrafluoroethylene, soaking in the reinforcing agent for 30 minutes, taking out, naturally air-drying for 3 hours, soaking again for 15 minutes, naturally air-drying for 3 hours, soaking again for 5 minutes, and naturally air-drying for 24 hours for later use.

2. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps:

the four-stage advanced treatment unit comprises an active sand filter and an active carbon adsorption tank, wherein the inlet of the active sand filter is connected with the outlet of the three-stage chemical module, and the outlet of the active sand filter is connected to the active carbon adsorption tank; the outlet of the activated carbon adsorption tank is connected to the main outlet of the water treatment system;

3. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps:

the invention relates to an integration method of acid wastewater suitable for mines, which adopts the system and comprises the following steps:

step four, starting PZX reactor to treat waste water;

step six, monitoring the concentration of metal ions in the primary sedimentation tank on line, entering step eight when the concentration of the metal ions reaches a water outlet standard, namely when Cr is less than 0.5mg/L, Cu, less than 1.0mg/L, Pb, less than 1.0mg/L, Zn, less than 4.0mg/L, Cd, less than 0.1mg/L, As and less than 0.5mg/L, and otherwise, entering step seven;

step nine, starting the active sand filter to filter the wastewater;

4. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps: the number of the designed screen holes of the grid screen unit is 10.

5. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps: PZX the reactor unit is designed to have an upflow velocity of 15-20 m/h.

6. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps: the downward flow velocity of the activated carbon adsorption tank unit is 5-7 m/h.

7. The modular integrated method for acidic mine wastewater treatment according to claim 1, wherein the method comprises the following steps: the added medicaments in the mixing reaction tank unit comprise lime, poly-4-vinylpyridine, dimethylaminoethyl methacrylate, sodium polyacrylate and polyethyleneimine, the mass ratio of the lime to the poly-4-vinylpyridine to the dimethylaminoethyl methacrylate is 1:0.01:0.005:0.02:0.05, wherein the adding amount of the lime is determined according to the pH value in the tank, namely when the pH value is less than 8.5, the lime is continuously added, the adding mass concentration is 30-35 mg/L, and when the pH value is more than or equal to 8.5, the adding is stopped.