- Pre-settling Tank: Mine wastewater is pumped from underground to the pre-settling tank. The wastewater is stored and its flow rate is regulated to meet the requirement of a constant influent volume. Simultaneously, it achieves primary sedimentation of suspended solids, significantly reducing the amount of suspended solids in the water and lowering the load on subsequent treatment units. A sludge scraper collects sludge from the bottom of the pre-settling tank and removes it periodically.
- High-Density Sedimenter: The high-density sedimenter integrates mechanical mixing and coagulation, mechanically enhanced flocculation, and inclined tube sedimentation separation. A return pump at the end of the sedimentation zone returns the activated sludge to the flocculation reaction zone, greatly improving and enhancing the flocculation and sedimentation effects. It shows significant advantages in treating low-temperature, low-turbidity water.
- Multi-media Filtration + Activated Carbon Filtration: The supernatant discharged from the high-density sedimentation tank contains a very small amount of fine suspended solids. The water flows by gravity into an intermediate tank and is then pumped sequentially to a multi-media filter and an activated carbon filter by a lift pump. This further filters the fine suspended solids in the wastewater to meet the influent quality requirements for ultrafiltration.
After prolonged filtration, a significant amount of sludge accumulates on the surface of the filter sand layer, clogging it and causing increased operating pressure, slower filtration speed, and a rising filtration level. Backwashing is then necessary. A high-volume backwash pump pumps filtered clean water into the filter from the bottom, accompanied by high-pressure air, creating an air-water mixture for backwashing. This loosens the sand layer, causing it to expand. Fine suspended solids in the system are then freed from the filter layer by the high-speed airflow and water, flowing out of the filter from the top and into the equalization tank for further treatment. After the backwashing process, the filter returns to its original flow rate and is ready for reuse.
- Ultrafiltration The ultrafiltration feed water first enters a disc filter to protect the ultrafiltration system from mechanical damage. The ultrafiltration system uses external pressure membrane modules; wastewater enters from the outside of the membrane fibers to the inside of the tube, operating in full-volume filtration mode. All permeate enters the ultrafiltration permeate buffer tank.
The ultrafiltration system is equipped with periodic backwashing, approximately every 20-40 minutes. Using a UF backwash pump, ultrafiltration permeate enters from the permeate side of the UF membrane, briefly flushing the membrane surface to remove deposits and restore membrane performance.
The entire ultrafiltration system is designed for fully automatic control, with programmed routines for normal filtration, air and water backwashing, and online chemical cleaning. Backwash water can be returned to the backwash water buffer tank for reprocessing. The ultrafiltration system also includes an offline chemical cleaning system, allowing for independent and group cleaning of individual membrane modules without requiring removal from the equipment.
