Enhancement Biosorption of Activated Sludge Process on Heavy Metals: Cadmium (Cd) And Nickel (Ni)

Environmental Engineering Department, Faculty of Engineering, Diponegoro University, Tembalang, Semarang, 50275, Indonesia

^* Corresponding author: junaidiundip@gmail.com

Abstract

This study focuses on Actived sludge treatment is carried out by a continuous reactor. Merriote tube capacity of 10L with a discharge of 10L/day as an inlet. Next to the 10L volume aeration tank where biological treatment occurs, pH 7 ± 0.2 and DO ≥ 3mg/L are the control variables. COD, Cd and Ni are taken for testing inlet and outlet. Artificial waste is used as an inlet with a nutrient ratio of C: N: P is 100: 5: 1. Seeding stage occurs 13 days to get an MLSS value ≥ 2000mg / L. Acclimatization I for adapting microorganisms to the environment occurred for 27 days and acclimatization II for 11 days as microbial ada ptation to heavy metals. Increasing t h e C / N ratio f ro m 20 to 50 will reduce the efficiency of COD removal from 74.5% to 65.38%, Cd removal from 24.3% to 32.3% and Ni removal 13.8% to 28.5%. Initial metals reduced the efficiency of COD removal at low, middle and high levels by 82.5%, 71.75%, 55.875%, respectively. Initial metals at low, middle, and high levels were obtained Cd removal efficiency of 0%, 52.2%, 32.6% and Ni removal efficiency of 0%, 36.3%, 27%, respectively. Optimal response for COD removal is 68.5% with factor initial metal middle and ratio C/N 50.