【Overview】
Čistá voda/ultrapure water treatment equipment refers to the water in which the conductive medium in the water is almost completely removed, and the non-dissociated gas, colloid and organic matter (including bacteria) are also removed to a very low degree. The electrical conductivity is generally 0.055～0.1us/cm, the resistivity (25℃)>10x106Ω•cm, and the salt content
Commonly used pure water treatment processes are:
- EDI elektrodialyzačná technológia
- Technológia membránovej úpravy vrátane ultrafiltrácie, reverznej osmózy atď.
- Technológia iónovej výmeny
STARK water treatment produces pure water treatment such as EDI electrodialysis, ion exchanger, ultrafiltration equipment, reverse osmosis system, etc., which are widely used in the preparation of pure water and high-purity water such as food pure water treatment, beverage pure water treatment, and pharmaceutical pure water treatment.
【Electrodialysis】
Electrodialysis is the migration of charged solute particles (such as ions) in a solution through the selective permeability of a semipermeable membrane under the action of an electric field.
EDI electrodialyzer under the action of DC electric field, the directional movement of the dielectric ions in the water through the separator, because the exchange membrane is selective for ions. Between a pair of electrodes of the EDI electrodialyser, the negative membrane, the positive membrane and the separators (A, B) are alternately arranged in groups to form the thick chamber and the thin chamber (that is, the cations can pass through the cationic membrane, and the anions can pass through the cationic membrane. membrane). The cations in the fresh water migrate to the negative electrode through the cationic membrane and are intercepted by the negative membrane in the concentration chamber; the anions in the water migrate towards the positive electrode through the negative membrane and are intercepted by the cationic membrane in the concentration chamber, so that the number of ions in the water passing through the fresh chamber gradually decreases, It becomes fresh water, and the water in the concentration chamber, due to the continuous influx of anions and cations in the concentration chamber, the dielectric ion concentration continues to rise, and becomes concentrated water, so as to achieve the purpose of desalination, purification, concentration or refining. Compared with reverse osmosis membrane separation pure water treatment technology, the price is cheap.
The application range of EDI electrodialyzer for pure water treatment is more and more extensive. EDI electrodialyzer is widely used in water desalination and desalination, seawater concentration and salt refining to refine dairy products, fruit juice deacidification and purification, preparation of chemical products, etc. It is suitable for water supply treatment in electronics, medicine, chemical industry, thermal power generation, food, beer, beverage, printing and dyeing and coating industries, such as food pure water treatment, beverage pure water treatment, pharmaceutical pure water treatment and other pure water and high-purity water preparation.
[Ion exchange]
Ion exchange equipment is widely used in the field of pure water treatment. Ion exchangers are divided into sodium ion exchanger, cation anion bed ion exchanger, mixed bed ion exchanger, floating bed ion exchanger, etc.
Ion exchange equipment is mainly used for water treatment of medium and low-pressure boilers, thermal power plants, chemical industry, light industry, textile, pharmaceutical, biological, electronic, atomic energy, and the preparation and treatment of pure water and high-purity water, as well as occasions where hard water softening and deionized water preparation are required for industrial production. Ion exchange equipment can also be used for decolorization and purification of food and drugs, recovery of precious metals and chemical raw materials, electroplating wastewater treatment Heavy metal sewage treatment is widely used in the preparation of pure water and high-purity water, such as food pure water treatment, beverage pure water treatment, pharmaceutical pure water treatment, etc.
Cation anion exchanger has the advantages of low pretreatment requirements for water and low cost.
When the total salt content of influent water is below 400mg/l, according to the requirements of pure water treatment, the conductivity of effluent water quality of anion and cation exchanger is 1.0-0.2 μ S/cm. If the total salt content of influent is more than 500mg/l, it can be desalted together with electrodialyzer and reverse osmosis, and the effluent quality of pure water treatment can be improved. Jiangsu Ruizhi environmental protection company produces large, medium and small ion exchange equipment. According to the inlet water quality and the outlet water requirements of the pure water treatment system, it can provide users with independent engineering design, auxiliary equipment matching, installation and commissioning, formulate operating procedures, and train operators. After the pure water treatment system is put into operation, it will be maintained at any time, and lifelong technical support will be provided for environmental protection equipment.
[ultrafiltration]
Ultrafiltration technology is a high-tech widely used in water purification, solution separation and concentration, as well as extracting useful substances from wastewater, wastewater purification and reuse. The pure water treatment equipment has the advantages of simple use process, no heating, energy saving, low-pressure operation and small floor area.
The ultrafiltration equipment takes the ultrafiltration membrane as the core product to filter the water quality, and uses the interception ability of porous materials to physically intercept and remove certain sized impurity particles in the water. Under pressure, small-sized substances such as water, organic low molecules and inorganic ions in the solution can reach the other side of the membrane through the micropores on the fiber wall, while large-sized substances such as bacteria, colloids, particles and organic macromolecules in the solution cannot be intercepted through the fiber wall, so as to achieve the purpose of screening different components in the solution. The process is operated at normal temperature without phase change and secondary pollution.
The molecular cutting weight (cwco) of ultrafiltration equipment is generally 6000 to 500000, and the pore diameter is 100nm (nm). The membrane used for ultrafiltration is asymmetric, and the average pore size of its surface active separation layer is about 10 ~ 200, which can intercept macromolecules and colloidal particles with molecular weight of more than 500, and the operating pressure difference is 0.1 ~ 0.5MPa.
In the field of pure water treatment, ultrafiltration equipment can remove bacteria, viruses, heat sources and other colloidal substances in water, so it is used to prepare ultra pure water treatment for electronic industry, injections for pharmaceutical industry, purified pure water treatment for various industrial water and purification of drinking water. It is widely used in the separation, concentration and purification of substances, and the preparation of pure water and high-purity water, such as pure water treatment for food, pure water treatment for beverage, pure water treatment for pharmaceutical, etc.
[Reverse Osmosis]
Reverse osmosis pure water equipment is a membrane separation technology. The pore diameter of reverse osmosis membrane is basically the same as that of water molecules. Only particles similar to the size of water molecules can pass through, and other particles or impurities can be separated, so as to purify the raw water. With the help of the membrane separation technology driven by pressure by selecting permeable (semi permeable) membranes, when the pressure applied in the system is greater than the osmotic pressure of the influent solution, water molecules continuously penetrate the membrane, flow into the central pipe through the water production channel, and then the impurities, such as ions, organics, bacteria, viruses, etc., that flow out of the water at one end are intercepted at the water inlet side of the membrane, and then flow out at the concentrated water outlet end, So as to achieve the purpose of separation and purification of pure water treatment.
With the continuous reduction of reverse osmosis pure water treatment equipment cost and operation cost, more and more industries (electric power, petroleum, coal, chemical industry, etc.) are using reverse osmosis system to produce desalted water for various processes. Reverse osmosis equipment applies membrane separation technology, which can effectively remove charged ions, inorganic substances, colloidal particles, bacteria and organic substances in water. It is an ideal pure water treatment equipment in high-purity water preparation, brackish water desalination and wastewater treatment processes. It is widely used in electronic, pharmaceutical, food, beverage, textile, chemical, power plant and other fields, such as food pure water treatment, beverage pure water treatment, pharmaceutical pure water treatment, etc.
Reverse osmosis system generally includes pretreatment system, reverse osmosis device, post-treatment system, cleaning system and electrical control system. The typical process flow of ultra pure water treatment equipment is as follows:
1. Pretreatment - reverse osmosis - purified water tank - ion exchanger - UV lamp - pure water pump - water point
2. Pretreatment - primary reverse osmosis - secondary reverse osmosis (positive charge reverse osmosis membrane) - purified water tank - pure water pump - UV lamp - water point
3. Pretreatment - reverse osmosis - intermediate water tank - intermediate water pump - EDI device - purified water tank - pure water pump - UV lamp - water point
4. Pretreatment → ultraviolet sterilization device → primary RO device → secondary RO device → intermediate water tank → EDI device → deoxygenation device → nitrogen sealed pure water tank → removal of TOC UV device → polishing mixed bed → ultrafiltration device → water point
The effluent quality of the pure water treatment system meets the American ASTM standard and the ultra pure water quality standard of the Ministry of Electronics (grade 4: 18m Ω *cm, 15m Ω *cm, 2m Ω *cm and 0.5m Ω *cm)
The pretreatment system generally includes raw water pump, dosing device, quartz sand filter, activated carbon filter, precision filter, etc. The main function is to reduce the pollution index of raw water and other impurities such as residual chlorine, so as to meet the requirements of reverse osmosis. The equipment configuration of pretreatment system shall be determined according to the specific conditions of raw water.
The reverse osmosis device mainly consists of multi-stage high-pressure pump, reverse osmosis membrane element, membrane shell (pressure vessel), support, etc. The main function is to remove impurities in the water and make the effluent meet the use requirements.
The post-treatment system is added when the reverse osmosis cannot meet the effluent requirements. It mainly includes one or more equipment such as anion bed, cation bed, mixed bed, sterilization, ultrafiltration, EDI, etc. The post-treatment system can better improve the effluent quality of reverse osmosis to meet the requirements of pure water treatment.
The cleaning system is mainly composed of cleaning water tank, cleaning water pump and precision filter. When the polluted effluent index of the reverse osmosis system cannot meet the requirements, it is necessary to clean the reverse osmosis system to restore its efficacy.
The electrical control system is used to control the normal operation of the whole reverse osmosis system. Including instrument panel, control panel, various electrical protection, electrical control cabinet, etc.
