Industries that require wastewater treatment are: chemical, paper, printing and dyeing, leather, food processing, breeding plants, medical treatment, slaughtering, pharmaceuticals, new villa complexes, coal mines, steel, oil fields, hotels.
Modern sewage treatment technology can be divided into primary, secondary and tertiary treatment according to the degree of treatment. Generally, the degree of sewage treatment is determined according to the water quality status and the whereabouts of the treated water.
It mainly removes suspended solid pollutants in sewage. Most of the physical treatment methods can only meet the requirements of primary treatment. After primary treatment, BOD can be removed by about 30%, which can not reach the discharge standard. The primary treatment belongs to the pretreatment of the secondary treatment.
It mainly removes colloidal and dissolved organic pollutants (BOD, COD substances) in sewage. The removal rate can reach more than 90%, which makes the organic pollutants reach the discharge standard. The suspended matter removal rate reaches 95%.
Further treatment of difficult-to-degrade organic matter, soluble inorganic matter such as nitrogen and phosphorus that can cause eutrophication of water bodies. The main methods are biological nitrogen and phosphorus removal method, coagulation sedimentation method, sand filtration method, activated carbon adsorption method, ion exchange method and electrodialysis method.
The whole process is that the raw sewage passing through the coarse grille is lifted by the sewage lifting pump, then passes through the grille or screener, and then enters the sedimentation tank. Treatment). The effluent from the primary sedimentation tank enters the biological treatment equipment. There are activated sludge method and biofilm method. Rotary table, biological contact oxidation method and biological fluidized bed), the effluent of biological treatment equipment enters the secondary sedimentation tank, the effluent of the secondary sedimentation tank is sterilized and discharged or enters the tertiary treatment. The stage treatment includes biological denitrification and phosphorus removal method, coagulation sedimentation method, sand filtration method, activated carbon adsorption method, ion exchange method and electrodialysis method. Part of the sludge from the secondary sedimentation tank is returned to the primary sedimentation tank or biological treatment equipment, and part of it enters the sludge concentration tank, and then enters the sludge digestion tank. After dewatering and drying equipment, the sludge is finally used.
The most important ones are:
Centrifuges are mainly used to separate solid particles from liquids in suspensions; or to separate two liquids of different densities in emulsions that are incompatible with each other (such as separating cream from milk); it can also be used to exclude Liquids in wet solids, such as washing clothes to dry clothes with a washing machine; special ultra-speed tube separators can also separate gas mixtures of different densities; using solid particles of different densities or particle sizes with different sedimentation speeds in the liquid, and some sedimentation Centrifuges can also classify solid particles by density or particle size.
Sludge dewatering machine
The characteristics of sludge dewatering machine are automatic control operation, continuous production, stepless speed regulation, suitable for a variety of sludges, suitable for sludge dewatering in various industries such as water supply and drainage, papermaking, casting, leather, textile, chemical, food and other industries. .
The aerator is used to inject "microbubbles" directly into the untreated sewage through a diffuser impeller. Under the combined action of coagulant and flocculant, the suspended matter undergoes physical flocculation and chemical flocculation, thereby forming a large suspended matter. The floc, under the action of the floating group of bubbles, "floc" floats on the liquid surface to form dross, which is separated from the water by a slag scraper; no nozzle cleaning is required, and no clogging occurs. This equipment has good integrity, convenient installation, saving operating costs and occupying the ground.
The micro filter is a rotary drum type screen filter device. The treated wastewater enters the drum along the axial direction and flows out through the screen in a radial shape. The impurities (fine suspended matter, fibers, pulp, etc.) in the water are trapped on the inner surface of the screen on the drum. When the impurities trapped on the screen are brought to the upper part by the drum, they are flushed back into the slag discharge tank by the pressure flushing water and flow out. During operation, the diameter part of the drum 2/5 is exposed to the water surface, the number of revolutions is 1-4r / min, the filtering speed of the filter can be 30-120m / h, the pressure of the washing water is 0.5-1.5kg / cm2, and the amount of washing water is the amount of production water 0.5-1.0%, when used in reservoir water treatment, the algae removal efficiency reaches 40-70%, and the plankton removal efficiency reaches 97-100%. The micro-filter has a small footprint and a large production capacity (250-36000m3 / d), and is easy to operate and manage. It has been successfully used in water supply and wastewater treatment.
Air flotation machine
Air flotation machine is a kind of equipment to remove suspended matter, grease and various glues in various industrial and municipal sewage. This equipment is widely used in the treatment of industrial wastewater and municipal wastewater such as oil refining, chemical industry, brewing, slaughtering, electroplating, printing and dyeing.
According to the dissolved gas method, it is divided into: inflatable air floater, dissolved air floater and electrolytic air floater. The principle is to efficiently mix gas or two or more different liquids that are difficult to dissolve in water (producing fine bubble diameter of 20-50 microns). The micro-bubbles are used as the carrier, and the particles of impurities in the water are adhered. The particles are lifted by the bubbles to the water surface and separated from the water to achieve the purpose of solid-liquid separation.
Ozone is a strong oxidant. It can decompose large molecules of organic matter into small molecules, decompose hardly soluble matter into soluble matter, convert hardly degradable matter into degradable matter, and decompose harmful matter into harmless matter, thereby achieving sewage. The role of purification.
Product Features of Sewage Treatment Ozone Generator
1. Ozone is an excellent oxidant, which can completely decompose organics in sewage.
2. It can kill all pathogenic microorganisms including viruses and spores with strong chlorine resistance.
3. In the process of sewage treatment, it is less affected by conditions such as pH and temperature of sewage.
4. Ozone is decomposed into oxygen, which increases dissolved oxygen in water and improves water quality.
5. Ozone can decompose large molecules of difficult-to-degrade organic matter into small molecule organic matter, and improve the biodegradability of sewage.
6. Ozone will be completely decomposed in the sewage, and will not cause secondary pollution due to residues.