1. Product Overview

　　In recent years, with the development of wastewater treatment technology, MBR, advanced oxidation, electrochemistry and other processes for high-efficiency purification of wastewater have developed rapidly. However, these processes are often difficult in technology, high cost of operation and maintenance or large demand for chemicals, which are not suitable for the general application of sewage treatment in economically underdeveloped areas.
　　Improved a 2O + BAF sludge doubling integrated sewage treatment series N (pwt-n) is a sewage purification equipment completely independently developed by Beijing Huayu brilliant Ecological Environmental Protection Technology Co., Ltd. The main process is a? O + two-stage clarification + BAF, which can effectively purify domestic sewage. The designed service water volume of pwt-n series equipment is 30t / D ~ 300t / D, which is suitable for sewage treatment in rural villas, scenic spots, public toilets, river interception and temporary emergency.
The application of pwt-n series equipment in rural domestic sewage treatment can ensure that the effluent quality can meet the discharge requirements of class a standard in integrated discharge standard of pollutants for urban sewage treatment plant (GB18918-2002), promote the construction of new socialist countryside and help to create a more harmonious rural living environment.

Main features:
　　(1) Microporous aeration technology and oxygen mass transfer efficiency are high;
　　(2) Less mechanical and electrical equipment, saving power, low operating cost;
　　(3) Sludge doubling + two-stage clarification technology, the effluent SS is stable;
　　(4) The effect of biological nitrogen and phosphorus removal is good;
　　(5) The static pressure BAF filter can guarantee the effluent;
　　(6) PLC intelligent remote control, no personnel on duty.

2. Product composition
　　Pwt-n is composed of equipment room, anaerobic tank, anoxic tank, aerobic tank, primary clarifier, dosing reaction tank, secondary clarifier and hydrostatic BAF filter, as shown in Figure 1.

Figure 1 Composition of pwt-n unit
 

3. Process flow

Figure 2 pwt-n process flow
 

　　The pwt-n series equipment is mainly composed of a? O + two-stage clarification + BAF, which combines the imported microporous aeration technology, two-stage clarification technology and sludge doubling technology. In the biochemical system, suspended sludge and fixed sludge exist at the same time; through the switch of anaerobic anoxic aerobic environment, different kinds of microorganisms absorb and consume pollutants in the biochemical system. In the dosing reaction tank, large lump sludge is formed by flocculation. With the sludge doubling technology, high-density alum flocculent is formed, and the flocculation sedimentation capacity is obviously improved. At the same time, the effect of biochemical phosphorus removal was enhanced by adding chemical phosphorus to ensure that the phosphorus in effluent reached the standard. The two-stage clarification process can completely separate the sludge water mixture, especially the secondary clarifier has excellent high-speed clarification effect under the action of high-density alum and inclined plate to ensure that the SS in the effluent reaches the standard. Static pressure BAF filter is also set in the clarification system. The residual dissolved pollutants and fine impurities in the water are removed by adsorption, and the sewage is thoroughly purified.
　　In order to ensure the normal operation of the mechanical and electrical equipment in the system, before entering the system, the sewage needs to pass through the regulating pool to balance the water quality and quantity, and at the same time, the basket grille and other mechanical filtering devices are used to remove solid impurities such as waste fiber. The space for expanding process is reserved in the system equipment room, which can realize the purpose of disinfection and reuse of produced water.

4. Product specifications and parameters

4.1 product model description

Table 1. Technical parameters of products

5. Inlet and outlet water quality

Table 2. Water quality parameters of inlet and outlet water

Note: the effluent quality meets the class a standard in the integrated discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002).
 

6. Product economic performance table

Table 3. Economic performance of products
 

7. Application scenarios