Basic methods for wastewater treatment

For high-concentration organic wastewater, the general approach is: 1. Physicochemical pretreatment to remove most of the organic matter, increase the B/C ratio, and improve the biodegradability of the wastewater. 2. Biochemical treatment to ensure emissions meet or are basically in line with the specified standards.

Urban wastewater treatment processes mainly include mechanical treatment, biological treatment (aeration tank), sludge treatment, and other stages. The mechanical treatment section includes structures such as grids, grit chambers, and primary sedimentation tanks, which are used to remove large particles and suspended solids. The principle of operation is to achieve solid-liquid separation through physical methods, thereby separating pollutants from the wastewater. Biological treatment of wastewater: Aimed at removing insoluble suspended solids and solvent-based biodegradable organic matter, its processes fall into four categories: activated sludge method, biofilm method, biological stabilization pond method, and land treatment method. Sludge treatment and disposal processes include: sludge concentration, sludge dewatering, and sludge stabilization.

For ammonia nitrogen and oily wastewater, biochemical methods are used

The principles of wastewater treatment are threefold (as summarized by myself): to minimize treatment costs, to reduce discharge as much as possible, and to reuse useful substances. Therefore, for wastewater treatment, the first step is to determine whether there are any reusable resources in the wastewater; if so, single-stage treatment is carried out based on their concentration. Secondly, there are many methods for wastewater treatment. Based on the methods used by our company for wastewater treatment, physical methods, membrane extraction techniques, distillation, rectification, evaporation, stripping, chemical reactions, and so on can all be employed; moreover, biochemical treatment can also be considered depending on the quality and quantity of the wastewater. So in this process, handling fees and operating costs are very important. The more methods there are, the more careful one needs to be in making a choice. Thirdly, it would be best if no emissions were needed at all. Of course, this not only brings environmental benefits but also more tangible economic advantages; however, the costs involved may increase significantly, so it’s necessary to do some calculations to determine what is most appropriate. Last edited by Seeking Help on 2009-2-18 10:14]

Basic methods for wastewater treatment: The first is physical methods, including coagulation sedimentation and air flotation, which use physical means rather than chemical or biological methods to remove pollutants from wastewater； The second is the chemical method, which involves using oxidants, high-energy agents, etc. to cause chemical changes in the form of pollutants in water bodies, or to remove them from those water bodies; this is what is meant by the chemical method ； Third is the physicochemical method, in which the substances added have both physical and chemical effects; for example, the addition of divalent iron ions along with hydrogen peroxide enables the removal of pollutants through oxidation and coagulation sedimentation – this is the physicochemical method ； The fourth method is the biochemical approach, which involves the decomposition and metabolism of pollutants by microorganisms in order to achieve purification. This type of method is further divided into anaerobic, facultative anaerobic, and aerobic methods, depending on the types of microorganisms that play a key role under different environmental conditions. Of course, this is related to the biodegradability of the wastewater, that is, to the extent to which microorganisms can break it down ； Wastewater treatment does not involve a single method; it is generally a combination of various approaches. Physical methods include things such as oil separation tanks, air flotation units, grids, and primary sedimentation tanks used before biological treatment. Anaerobic and aerobic methods belong to biological treatment techniques, while disinfection is a chemical process. Therefore, the method chosen for wastewater treatment is determined based on the properties of the wastewater, with the goal of achieving the best treatment results, minimizing investment, reducing treatment costs, and simplifying operations.

There are many types of wastewater. Domestic wastewater needs to be treated through biochemical methods; here we use MBR to treat domestic sewage. As for industrial wastewater, we employ flocculation sedimentation along with secondary filtration for its treatment, and this industrial wastewater is then reused

What’s written upstairs is very detailed! ! !