Study of a Wastewater Treatment System from a Paper Industry

Abstract

This project aims to study a wastewater treatment system from a paper industry based on a rotating biological contact reactor (RBC). The wastewater was characterized, concluding that the effluent can’t be discharged directly because it does not comply with the concentrations established in Registro Oficial N° 387 of November 4, 2015 of the Republic of Ecuador in the parameters of BOD, COD, settle able, suspended and total solids. The study started with a sedimentation treatment on a laboratory scale without the addition of flocculants and coagulants, which allowed the removal of settle able solids. Then it went to a RBC whose initial volume was 3.0 L: 2.7 L of wastewater and 0.3 L of inoculum of microorganisms; the stabilization time of the microorganisms was 14 days. Subsequently, a treatment was carried out by means of an open filter of sand and gravel on a laboratory scale with a height of 55 cm of precipitated silica sand. These treatments allowed compliance with environmental regulations for the control of liquid discharges. The treatment system was designed for a flow of 140 m3/day, which has a storage tank of 32.67 m3, a settler of 30.00 m3, a RBC of 35.95 m3 with 150 polyethylene disks and two open sand and gravel filters of 11.66 m3.