I. Basic information of enterprises and sewage treatment plants Xinjiang Meike Chemical Co., Ltd. (hereinafter referred to as "Meike Chemical") is a joint stock limited company established by Xinjiang Meike Chemical Co., Ltd. and controlled by Meike Investment Group Co., Ltd. The company is located in Meike Chemical Industrial Park, Economic and Technological Development Zone, Korla City, an important town in southern Xinjiang, with a total area of about 2.7 square kilometers and about 1,200 employees. The company's second-phase project has a sewage treatment station with a daily processing capacity of 2,000 cubic meters, mainly using air flotation device, micro-electrolysis device, coagulation and sedimentation device, PAM dosing device, hydrogen peroxide dosing device, anaerobic tank, hydrolysis and acidification tank, contact oxidation pool.

The main tasks of sewage treatment station construction:

1. Start the FOD device (micro-electrolysis iron-carbon electrode) to pretreat high-concentration wastewater

2. Start the air flotation equipment to remove oily substances with lighter specific gravity.

3. Cultivate the biochemical system.

2.The status quo of the biochemical system

The 2 anaerobic towers are about 5000 cubic meters, and the 3 contact oxidation tanks are about 5250 cubic meters. Since there is no domestic sewage treatment plant in Xinjiang, there is no source of activated sludge, so pig manure is selected to replace activated sludge for biochemical system cultivation.

3. Biochemical system startup plan

(1) Anaerobic tank culture scheme

The anaerobic tank has a total of about 5,000 cubic meters, and 50 cubic meters of pig manure and 1,000 kilograms of anaerobic bacteria are added at one time to start anaerobic reflux. Detect the pH value of the anaerobic tank to ensure that the anaerobic pH value must not be lower than 6.5, and the pH value No higher than 7.5, anaerobic culture for 15 days (no industrial sewage is allowed during this period).

Nutrient addition: Add 3 bags of flour and 3 kg of diammonium phosphate to the anaerobic tank every day, and directly add them to the reflux tank and circulate to the anaerobic tank.

Gradient inflow: After 15 days of anaerobic culture, adopt gradient inflow, and monitor the COD value in the anaerobic tank after water inflow. If there is a rebounding trend, you need to reduce the amount of water inflow, and the pH value of the influent water is guaranteed to be between 6.5-8. (that is, the PH value of the water after FOD treatment), some domestic sewage can be added during the domestication period, and industrial wastewater can be added later.

(2) Hydrolysis and acidification tank

Since the return pipeline of the secondary sedimentation tank was connected to the hydrolysis and acidification tank, a large amount of sludge accumulated in the hydrolysis and acidification tank and could not be recycled. Therefore, the hydrolysis and acidification tank should be cleaned before normal start-up.

(3) Contact oxidation pool

The volume of 3 groups of aerobic pools is 5250 square meters, and 300 kg of aerobic bacterial agent is added to each aerobic pool at one time to monitor the pH value change of the aerobic pool. If the pH value becomes lower, sodium carbonate should be added to adjust the pH value.

Nutrients: 3 bags of flour and 5 kg of diammonium phosphate should be added every day for aerobic conditions for 10 consecutive days.

Gradient influent: After culturing for 10 days, gradient influent is adopted, and the influent is increased according to the gradient of anaerobic influent, and the COD of anaerobic and aerobic effluent is monitored. If the COD of effluent is too high, the influent needs to be reduced.

Nutrient addition plan after normal startup: Add 3 bags of flour, 20 kg of urea, and 6 kg of diammonium phosphate to the nutrients regularly after the normal startup of the contact oxidation tank.

When contacting the oxidation tank, attention should be paid to the return of sludge to ensure that the sludge concentration is about 30%.

4. Pay attention

Strictly control the pH value and COD stability of the biochemical system after FOD treatment.