In the process of papermaking wastewater treatment, black liquor, beating wastewater and white water are the key links.
The treatment of papermaking black liquor is the key to the wastewater treatment of the papermaking industry. At present, the commonly used papermaking black liquor treatment technologies include alkali recovery method and flocculation precipitation method.
Beating sewage: The sewage discharged from the pulp through the beater has the same composition as the black liquor, but the concentration is lower. Due to the small amount of organic substances (fibers, alkalis, etc.) contained, recovery is difficult, but the total solids, suspended solids and BOD5 in the sewage are still very high, and direct discharge still causes serious pollution to the water body, so it needs to be treated. The main treatment methods include coagulation and precipitation.
Papermaking wastewater treatment process
The papermaking sludge treatment uses a belt filter press for dewatering, which can dewater the sludge to a moisture content of 80% -85%; with a plate and frame filter press or a box filter press, it can be dehydrated to a moisture content of 75% -83%; With a membrane filter press, it can be dehydrated to a moisture content of 70% -78%;