The domestic sewage of a sewage plant in Shandong is used for urban greening after treatment, but in the existing process, the water quality is often not up to standard, and the treatment cost is relatively high, so it is necessary to choose a suitable water filter for treatment.
1. Project Overview.
1. The sewage treatment plant treats domestic sewage, adopts dosing treatment, and the treated water enters the pool for precipitation, and the supernatant is pumped to the clear water pool after precipitation, but it is easy to cause a pool of clean water to be polluted during the treatment process.
2. Large content of impurities suspended solids: In the process of sewage treatment, it is difficult to meet the sewage discharge standards, resulting in a large content of impurities suspended solids, which will cause secondary pollution to the environment.
3. The whole sewage treatment process requires the staff to check on site all the time, and the labor cost is high.
2. Water sample analysis.
The suspended solids in the water after the sewage is found to contain 100mg L.
3. Solution.
Due to the poor water quality of the sewage pool on site and the high content of suspended solids impurities, 3 shallow sand filters and 1 bag filter were used. First, a shallow sand filter is used to filter out suspended solids and large particle impurities in the water, and then a bag filter is used to carry out fine filtration to filter out fine particle impurities in the water, so that the effluent water quality meets the requirements.
The technical parameters are as follows:
Combination form: shallow sand filter + bag filter.
Material: carbon steel.
Flow rate: 150t h
Inlet pressure: 02mpa
Backwash water flow: 35m h
Backwash method: endogenous backwash.
Control mode: dual control of time and differential pressure.
Fourth, the use of effects.
1. The domestic sewage is now passed through the shallow sand filter, which plays the role of coarse filtration, filters out large particles of impurities in the water, reduces turbidity, and the pressure difference reaches the set value to achieve backwashingUnder the effect of coarse filtration protection, the secondary fine filtration can extend the service life and maintenance cycle of the internal filter bag, saving labor and consumables costs.
2. After two-stage filtration, the SS content of suspended solids in the water is 10mg L, so that the effluent quality meets the requirements of irrigation water quality.
3. The shallow sand filter has a high degree of automation, can run backwashing, liberate manpower, secondary fine filtration protection, real-time alarm, and will not cause sewage to enter the clear water pool, resulting in secondary pollution.