Sludge formation in the activated sludge process with a sludge disintegration unit

The activated sludge process is one of the major aerobic processes used in the biological treatment of wastewater. A significant drawback of this process is the production of excess `sludge', the disposal of which can account for 50--60% of the running costs of a plant. We investigate how the volume and mass of excess sludge produced is reduced by coupling the bioreactor to a sludge disintegration unit. References A. O. M. Alharbi, M. I. Nelson, A. L. Worthy, and H. S. Sidhu. Sludge formation in the activated sludge process: Mathematical analysis. In Proc. Australasian Chem. Eng. Conf., Chemeca 2013. Chemical College, Engineers Australia, 2013. www.conference.net.au/chemeca2013/papers/29490.pdf Y.-C. Chung and J. B. Neethling. Viability of anaerobic digester sludge. J. Environ. Eng., 116(2):330–342, 1990. doi:10.1061/(ASCE)0733-9372(1990)116:2(330) M. I. Nelson, T. Kerr, and X. D. Chen. A fundamental analysis of continuous flow bioreactor and membrane reactor models with death and maintenance included. Asia-Pac. J. Chem. Eng., 3:70–80, 2008. doi:10.1002/apj.106 S.-H. Yoon. Important operational parameters of membrane bioreactor-sludge disintegration (MBR-SD) system for zero excess sludge production. Water Res., 37(8):1921–1931, 2003. doi:10.1016/S0043-1354(02)00578-