A method of treating industrial sewage belongs to the field of sewage treatment technology. It is the sewage to the catchment pond, the catchment pond at the end of a grid to adjust pH, with a dissolved air pump to lift to a first-class pressure dissolved air tank, while inhaling air and polycondensation decolorant, will be in a first-class pressure dissolved air tank within the first class of saturated dissolved air water suddenly released to a first class of air flotation pool to form a first class of water; first-class water overflow into the buffer tank, and then in the control of pH with a second class of dissolved air pump will be a first-class water lifted to the second class of dissolved pressure air tank, while inhaling air and polycondensation decolorant. Tank, while inhaling air and polycondensation decolorant, the secondary pressure dissolved gas tank in the secondary saturated dissolved gas water suddenly released to the secondary air flotation tank to form the second level of treated water and since the overflow to the sedimentation tank precipitation discharge; one or two air flotation tank in the floating sludge into the floating mud pool, filtering filter cake, filtrate back to the catchment pond. This method of treatment of industrial wastewater CODcr, decolorization rate, SS, BOD5 removal rate of 80-90%, 95%, 90% or more, 75-80%, in line with the GB8978-1996 primary water discharge standards.
2. Agricultural wastewater treatment methods
Agricultural wastewater because of the wide distribution of scattered, difficult to collect and difficult to manage, so can only use the role of biological pollutants will be removed, such as high-density high-efficiency decontamination bacteria, directly into the contaminated water, in order to achieve the purpose of water purification.
3. Treatment of medical sewage
Hospital sewage treatment, usually including primary and secondary treatment. Generally speaking, if the treated water is discharged into the municipal sewers, usually only primary treatment; if the treated water is discharged directly into the river, it is necessary to carry out primary and secondary treatment; on the discharge standard is strict, in order to prevent the eutrophication of the water body, need to carry out phosphorus denitrification tertiary treatment. Special hospital wastewater such as acidic wastewater, phase-washing wastewater and radioactive wastewater should be strictly collected and treated. In some areas, in order to alleviate the contradiction of water supply tension, the deep treatment and recycling of hospital sewage has been carried out. The actual way of hospital sewage treatment should take into account a variety of factors such as the source of sewage, the flow of sewage and the local water supply. In addition, a very important aspect of hospital sewage treatment is that it must be disinfected to kill a variety of pathogenic microorganisms.
Second - domestic sewage
〖Rural sewage treatment method〗
For rural sewage, the following treatment can be carried out:
The picture shows the domestic sewage in rural areas Domestic sewage → septic tank → anaerobic tank → artificial wetland (planted with plantain, water onion, calabash, etc., which have well-developed root system, like wet, strong absorption ability) by the The method of "filtering" and then discharging is mainly applicable to rural decentralized sewage treatment, and the operation cost is basically zero after the completion of the project, and the service life is more than 10 years.
〖Urban sewage treatment method〗
Life sewage treatment process For urban sewage, the following treatment can be carried out:
The urban sewage will be transported to the rural areas around the city, and the vast land in the countryside will be used to purify the urban sewage. Will be once and for all with a good way to kill many birds with one stone. The daily supply of domestic tap water 100W cubic meters of large and medium-sized cities, for example: ordinary sewage treatment facilities cost 1000 yuan / cubic meters. Construction cost of 1 billion, the annual operating cost of 100W cubic meters / day × 365 × 0.5 yuan / cubic = 180 million. Using soil purification method construction cost of 1000 yuan / cubic meter, the annual operating cost of 100W cubic meters / day × 365 × 0.1 yuan / cubic = 0.4 billion. At the same time, the annual savings of 360 million cubic meters of agricultural water resources, saving about 10,000 tons of fertilizer/year, reducing pesticide use 5 tons/year, the comprehensive benefits are considerable.
There are many sewage treatment facilities, but the main ones are the following:
1. Centrifuge
Centrifuges are mainly used to separate solid particles in suspension and liquid; or emulsion of two different densities, but also immiscible liquids separate (for example, from the milk out of the separation of cream); it can also be used to exclude the liquid in the wet solid, such as washing machines to shake the Dry wet clothes; special ultra-speed tube separator can also be separated from different densities of gas mixtures; the use of different densities or sizes of solid particles in the liquid settling speed of different characteristics, some sedimentation centrifuges can also be graded according to the density or size of solid particles.
Sludge dewatering machine 2. Sludge dewatering machine
Sludge dewatering machine is characterized by automatic control of the operation, continuous production, stepless speed regulation, for a variety of sludge applicable to a variety of sludge for water supply and drainage, papermaking, foundry, leather, textile, chemical, food and many other industries of sludge dewatering.
3. Aeration machine
The aeration machine is through the diffuser impeller, the "micro-bubbles" injected directly into the untreated sewage, in the coagulant and flocculant *** with the same action, the suspended material occurs in the physical flocculation and chemical flocculation, resulting in the formation of large flocs of suspended material in the bubbles group of the flotation role! "Under the floating action of air bubbles, the floc floats up to the liquid surface to form scum, which is separated from the water by scraping machine; there is no need to clean up the nozzle, and no blockage will occur. This equipment is good overall, easy to install, save operating costs and occupy the ground.
4. Microfilter
Microfilter is a drum-type screen filtration device. Treated wastewater along the axial into the drum, radial radial outflow through the screen, water impurities (fine suspended solids, fibers, pulp, etc.) that is retained in the drum on the inside surface of the screen. When the impurities retained in the screen is brought to the upper part of the drum, the pressure flushing water backwash to the slag discharge tank out. When running, the drum 2/5 diameter partially exposed to the water surface, the number of revolutions for 1-4r/min, the screen filtration speed can be used 30-120m/h, the pressure of the rinse water 0.5-1.5kg/cm2, the rinse water for the production of 0.5-1.0% of the amount of water, used in the water treatment of reservoirs, the efficiency of the removal of algae up to 40-70%, in addition to the efficiency of the plankton up to 97-100%. Microfilter covers a small area, large production capacity (250-36000m3/d), easy to operate and manage, has been successfully applied to water supply and wastewater treatment.
5. Air flotation machine
Air flotation machine is the use of vortex pump mixing function, the gas or more than two different liquids that are difficult to dissolve in the water efficiently pressurized mixing, resulting in micro-fine bubbles with a particle size of 20-50 microns. Stirring technology greatly simplifies the traditional mixing process, not only can realize the miniaturization of the equipment, but also save investment and operating costs.
Hope it can help you!