Treatment of Rosin Wastewater by Boiler Slag Adsorption and Activated Sludge Biodegradation

In the presented patent, wastewater treatment from pine gum resin processing had been studied and the suitable conditions for treating the wastewater were obtained. This patent utilized two processes: the primary treatment of boiler slag adsorption and the secondary treatment of activated sludge biodegradation. Under the primary treatment, the chemical oxygen demand (COD) and suspended substances (SS) in the wastewater were examined systematically at various slag's sizes and solution pH values. The suitable technological conditions of the slag adsorption treatment found were boiler slag size of 1.00-1.41 mm and solution pH value of 6.0. The adsorption experimental equilibrium data was found to fit the Langmuir model well, and the breakthrough curve of adsorption column test was also obtained. The effluent treated by the boiler slag adsorption was further treated by activated sludge biodegradation. The effects of aeration time and coagulation/ precipitation time on biodegradation process were studied and the suitable biodegradation conditions obtained were as follows: the coagulation/precipitation time of 60 min, the aeration time of 6 h for COD and aeration time of 8 h for SS, respectively.