The influence of wastewater from paper mills on the biological process in the municipal wastewater treatment plant

Abstract

Wastewaters resulting from paper mills have high organic loading that in most cases exceeds the maximum limits allowed for their discharge in the aquatic environment. In the context of concerns regarding the sustainable development of water resources, the identification of solutions for the optimal management of effluent treatment is a challenge of the modern society. This paper depicts the biological treatability of wastewaters resulting from the manufacturing of recycled paper and discusses their effect on the biological process after their admission in the municipal wastewater treatment plant. The Symons criterion and the Zahn-Wellens method were employed in order to study the biodegradability of organic substances as they are useful tools for prefiguring the behaviour of wastewaters during the secondary treatment step.