Wastewater treatment process

Under the pace of industrial development, urbanization and population growth, water resources in the territories are increasingly under increasing pressure. As a result, the water environment in many cities, industrial parks and craft villages is increasingly polluted by waste water, waste gas and solid waste. Water pollution from industrial production plays a large part in the overall pollution, in addition to the pollution from domestic wastewater.
Specifically, in typical industries such as textiles, paper and pulp, wastewater usually has an average pH of 9-11, biochemical oxygen (BOD), chemical oxygen (COD) up to 700mg / 1 and 2,500mg / 1, the suspended solids content is many times higher than the permitted limit. The wastewater content of these industries contains 84 times of cyanide (CNS), H2S exceeds 4.2 times, NH3 + content exceeds 84 times permitted standards, thus polluting surface water sources in residential areas It does not take into account industries that have a greater impact on the environment (such as plating, steel, food production, drinking water, etc.) and domestic waste water.
Wastewater treatment is a common problem of the whole society in general, of industries in particular. Today, the agencies under the Department of Natural Resources and Environment are implementing strict measures to prevent the maximum amount of waste generated by production.

Waste water treatment process

Wastewater from the plant's sources is fed into the receiving tank, with the raw garbage dump installed. The sludge is separated from the waste water.
After flowing through the receiving tank, the effluent is drained through the separating tank (for systems where required). Sewage is submersed sewage pumped into the refuse collection equipment to separate solid waste small size before self-flowing into the regulating tank. The mud is also separated.
The regulator is responsible for regulating the flow and concentration of pollutants in the effluent before putting it into the rear unit. Blowers are supplied to the tank to avoid disturbance.
Wastewater from the air-conditioning tank is pumped into a cotton flotation tank, and PAC and Polymer are used to perform the flocculation process. Stimulates the bonding of colloids in the wastewater to produce larger particles from the small particles that the raw and refined filtration equipment can not handle. The larger particles after the flocculation, the cotton in the waste water will be deposited and disposed of in the mud.
The wastewater then flows through the flotation system, where the mixture of air and waste water is mixed to form fine foam under atmospheric pressure, the air bubbles are separated from the water and the oil and some dangling. Grease and suspended solids are separated from the effluent by means of an automatic de-gage device directed to the sludge tank. Floating flotation systems combine flotation and flocculation to achieve high removal efficiency. At the same time, the phosphorus removal efficiency of the whole system has been improved by this work.
Waste water is passed through the anaerobic treatment tank. Highly contaminated wastewater will come into contact with the anaerobic sludge and all of the biochemical processes that will take place in the sludge, including hydrolysis, acidification, acetate, methane gas, and other final products.
The effluent from the activated sludge tank adheres to the spillway through the settling tank. Here, the phase separation occurs and the mud (microorganism) is retained. The sediment is pumped back to the anaerobic tank and the gas is reduced to maintain the concentration of microorganisms in the tank. The excess sludge is pumped into the silt reservoir. All of the sludge that has been treated is stored (sludge pressed) and the unit has a collection function.

Chemical treatment in wastewater treatment

Most of the conventional wastewater treatment processes use the above steps, depending on the type of wastewater that one or more of the wastewater is disposed of. For other special processes that fall outside of the generality of the procedure above, one or more of the following major processing systems shall also apply:

Mechanical treatment: remove waste, residue, ... through the filter, regulate the flow and concentration of wastewater.
Chemical treatment: coagulation - cotton - settling (not counting chlorine disinfection process).
Biological treatment (activated sludge) combines Nitrification and Denitrification: remove organic pollutants in wastewater.
Sludge treatment: reduce the moisture content of the sludge before disposal according to regulations.
So, in the wastewater treatment system, in addition to the fixed investments for other parts (mechanical, biological, sludge, etc.), the chemical treatment system is about continuous investment. Because of the peculiarity of chemicals, chemical products are often expensive when compared to the economic benefits of a wastewater treatment system. Therefore, the gluing of chemicals - cotton (sewing plays an important role in the handling of suspended particles smaller than 10-4mm) with accurate flow not only helps to complete the task of the process settling small particles, but also save the associated costs.