What is the process of wastewater treatment in a sewage treatment plant?

The sewage treatment process is as follows:

1. The wastewater first flows to the flocculation sedimentation tank after passing through the grid and screen, in order to make the treatment effect good, the coagulant is added to the flocculation sedimentation tank, so that the suspended solids in the wastewater treatment effect is better, the coagulation dosing also plays a role in regulating the wastewater, and the wastewater after flocculation and precipitation flows into the pre-aeration conditioning tank.

2. Air is introduced into the aeration conditioning tank to play the role of pre-aeration adjustment. The homogeneously regulated wastewater is pumped into a primary floating packing biochemical tank.

3. The aeration head with high oxygenation efficiency is installed in the biochemical tank and loaded with floating filler, which has proved that this technology has a high removal efficiency for COD and BOD. The wastewater in the primary floating filler biochemical tank flows into the secondary floating filler biochemical tank, and the method is the same in the second pool.

4. The water of the secondary floating packing biochemical tank flows into the inclined plate sedimentation tank. The addition of polypropylene honeycomb inclined pipe to the pool can greatly improve the settlement efficiency, in addition, the hydraulic load is high, the residence time is short, and the floor area is small.

5. The sludge precipitated by the coagulation sedimentation tank and the inclined plate sedimentation tank is discharged into the sludge thickening tank, and then dewatered by the sludge dewatering machinery.

6. The water discharged from the inclined plate sedimentation tank flows into the clear water tank and is discharged after testing.

The pollutants of the wastewater produced by domestic sewage are mainly proteins, carbohydrates, fats, urea and other microorganisms with a large number of pathogens, so they must be treated through the sewage treatment plant, and when the wastewater arrives at the treatment plant, it will generally be divided into four steps: pretreatment, biochemical treatment, advanced treatment, and disinfection. Therefore, the details of the treatment methods after the following domestic sewage enters the sewage treatment plant are as follows:

Step 1: Pretreatment is the key to initial interception, because it can intercept large suspended solids in the sewage through the coarse grid, and the wastewater after the interception will be left in the aeration tank after the second interception of the fine grid. The first step of pretreatment is completed by removing the organic matter attached to the surface of the wastewater.

Step 2: Biochemical treatment is the key to nitrogen and phosphorus removal of wastewater, generally through the principle of microbial degradation, so that it can achieve the purpose of nitrogen and phosphorus removal while treating wastewater.

Step 3: Advanced treatment is the core link of sewage treatment, because in this step, it must be chemically treated, and by adding demulsifiers, the suspended solids in the sewage, oil and colloidal particles can be quickly separated, so that they lose their repulsion and attractiveness, and flocculate into large sludge to sink and precipitate.

Step 4: Disinfection, after disinfection through ultraviolet cells and chlorine, it can be reused and discharged up to the standard.

Domestic sewage demulsifier can quickly reduce organic matter, SS, color, ammonia nitrogen, heavy metals and other excess substances in wastewater through flocculation and precipitation, which can be used alone or combined with process treatment to enhance the biodegradability of wastewater, provide favorable conditions for the follow-up biochemical system, thereby reducing the pressure on enterprises.

The process of sewage treatment in the sewage treatment plant is as follows:

1. Biological phosphorus removal.

In the process of economic development, China's major rivers and lakes are seriously eutrophicated due to phosphorus pollution, and the State Environmental Protection Bureau has formulated relatively strict standards for phosphorus discharge in order to control phosphorus pollution. The chemically enhanced biological phosphorus removal sewage treatment process is mainly to remove organic pollutants and various forms of phosphorus in the sewage, this sewage treatment process integrates chemical phosphorus removal and biological phosphorus removal, and produces volatile organic acids through the activated sludge in the anaerobic digestion biological system, which is used as the substrate or nutrient for the growth of polyphosphate bacteria, so that the polyphosphate bacteria can selectively proliferate in the activated sludge and return them to the biological system, so that the biological sewage treatment system works in a state of efficient phosphorus removal; At the same time, the phosphorus produced by the sludge under anaerobic conditions is released and eliminated by chemical phosphorus removal. This is an efficient municipal sewage treatment technology, which meets the requirements of further phosphorus removal on the basis of conventional secondary sewage treatment in order to solve the eutrophication of water bodies in China at this stage.

2. Circulation clearance.

China's economic development level varies greatly, and the city with lagging economic development can not come up with a lot of funds for sewage treatment, therefore, how to use limited funds to reduce environmental pollution is a problem faced by many cities. In terms of sewage treatment, until recently, some cities still adopted primary or primary enhanced treatment technology, and the effluent did not meet the requirements of the national secondary discharge standard for the removal of organic pollutants. The cyclic intermittent aeration process gives full play to the advantages of high load oxidation ditch treatment efficiency, and makes full use of the good effluent characteristics of the sequential batch activated sludge sewage treatment process to ensure that the effluent of the system meets the requirements of the national first-class sewage discharge standard in the removal of organic pollutants.

In terms of investment and operation costs, it is about 30% lower than the secondary biological sewage treatment system that usually removes organic pollutants, and is a process technology suitable for the current sewage treatment requirements in China.

3. Rotational contact.

Rotary contact oxidation wastewater treatment technology is a new generation of aerobic biofilm treatment technology developed on the basis of biological carousel technology and combined with the advantages of biological contact oxidation technology. Rotary contact oxidation wastewater treatment process technology and complete sets of equipment provide a simple and reliable method of wastewater treatment. The shaft in the entire sewage treatment system is the only rotating part, and if the machine fails, the general mechanic can carry out repairs.

The system biomass is automatically compensated for changes in organic load. The microorganisms attached to the turntable are alive, and when the organic matter in the sewage increases, the microorganisms increase, and conversely, when the organic matter in the sewage decreases, the microorganisms decrease. Therefore, the working effect of the sewage treatment system is not susceptible to sudden changes in flow and load and power outages.

The operating costs are low, with only one-eighth to one-third of the electricity consumed by other aeration wastewater treatment systems. The footprint is only half of that of conventional activated sludge methods. Due to the wide variety of microorganisms growing in the biological system, it can efficiently treat all kinds of refractory industrial wastewater.