INTEGRATED PHOTO-CATALYTIC AND ANAEROBIC TREATMENT OF INDUSTRIAL WASTEWATER FOR BIOGAS PRODUCTION Report to the WATER RESEARCH COMMISSION by OCHIENG AOYI, SETH O. APOLLO, JOHN AKACH, KWENA Y. PETE Centre for Renewable Energy and Water, Vaal University of Technology WRC Report No 2105/1/14 ISBN 978-1-4312-0648-3 March 2015 Obtainable from Water Research Commission Private Bag X03 GEZINA, 0031
[email protected] or download from www.wrc.org.za DISCLAIMER This report has been reviewed by the Water Research Commission (WRC) and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the WRC, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. © Water Research Commission ii EXECUTIVE SUMMARY _________________________________________________________________________________ Introduction: Anaerobic treatment of high strength wastewater is a widely accepted practice in the industry due to the fact that it converts the organic pollutants into biogas, which is a mixture of methane and carbon dioxide. As a result, this process leads to the reduction in chemical oxygen demand (COD) of industrial wastewater. Moreover, the biogas produced is a source of energy which can be used in industry or for domestic purposes to offset the ever increasing energy demand. Waste removal and methane yield are the key parameters used in the evaluation of an anaerobic digester (AD) performance in the anaerobic digestion process. The performance of ADs is inadequate in removing some biorecalcitrant wastes effectively. For this reason, advanced oxidation processed (AOPs) such photocatalytic degradation as well as integrated techniques have attracted a lot of interest in the recent years.