H3VV-8-C flender Helical gearboxes H3

Flender/Flender Gear Units/Helical gearboxes H3

cord their sincere thanks to the City of Tshwane and ERWAT as well as the following members of their staff: City of Tshwane Stephen van der Merwe Ludwig Regenstein Portia Ramasodi Philip Modikoe Kerneels Esterhuyse Operators & Support Staff at Zeekoegat wastewater treatment plant ERWAT James Topkin Norman Mahlangu Alone Mabunda Yolandi Jacobs-Botha Nyiko Khoza Alison Chapman Nora Motha Operators & Support Staff at JP Marais wastewater treatment plant Equipment Suppliers Hennie Basson (efTech) Lucinda Jooste (Xylem) viii This pag was intentionally left blank ix Table of Contents EXECUTIVE SUMMARY.......................................................................................................................iii ACKNOWLEDGEMENTS......................................................................................................................vii 1. BACKGROUND .................................................................................................................... ........................ 1-1 1.1 ENERGY EFFICIENCY IN WASTEWATER TREATMENT GLOBAL PERSPECTIVE ............................................................. 1-1 1.1.1 Global Studies ................................................................................................................ ...................... 1-1 1.1.2 South African Studies ......................................................................................................... .................. 1-2 1.2 ENERGY USE IN ACTIVATED SLUDGE PROCESSES .................................................................................................... 1-3 1.2.1 Overview ...................................................................................................................... ........................ 1-3 1.2.2 Energy Conservation Measures for Aeration Syst ems in Activated Sludge Plants ............................... 1-4 1.2.3 The Role of Advanced Process Modelling in E