Biofilms in Wastewater Treatment Systems
G.A. Clark Ehlers and Susan J. Turner
from: Microbial Biofilms: Current Research and Applications (Edited by: Gavin Lear and Gillian D. Lewis). Caister Academic Press, U.K. (2012)
Biofilms occur frequently inside various engineered systems for wastewater treatment. These include traditional trickling filter systems, modified lagoons, and specialized supplementary systems for nutrient removal or treatment of specialized wastes. The major advantages of biofilm systems over suspension treatment is the high microbial density that can be achieved, leading to smaller treatment system footprints, and the inherent development of aerobic, anoxic and anaerobic zones which enable simultaneous biological nutrient removal. The intrinsic resistance of biofilm communities to changing environmental conditions creates the added advantage that biofilm-based treatment systems are more resilient to influent variation in toxicity and nutrient concentrations. In contrast to biofilms of environmental or biomedical relevance comparatively little is known about development and stability in waste treatment systems. The advent of tools that enable the study of biofilms in reactor systems on a molecular level has enabled greater insight into the physiologically and biochemically relevant pathways that may facilitate optimized processes. In this chapter, the current literature on biofilms in wastewater treatment systems is reviewed and opportunities for further development in this field are identified read more ...