Factors Involved in Sludge Granulation under Anaerobic Conditions

Document Type : Research Paper


1 Prof. of Environmental Eng., Dept. of Chemical and Petrochemical Eng., Sharif University of Tech., Tehran

2 M.Sc. Student of Environmental Eng., Dept. of Chemical and Petrochemical Eng., Sharif University of Tech., Tehran


This paper investigates the effects of factors involved in sludge anaerobic granulation. Granulated sludge formation is the main parameter contributing to the success of UASB reactors. Anaerobic granulation leads to reduced reactor size, space requirement, and investment costs. Operation costs are also greatly reduced due to lack of aeration. An important parameter affecting process performance is the size of sludge granules; the factors involved in granule size will be investigated. Some of the important parameters of anaerobic sludge granulation are: existence of growth cores as inert particles or granulated sludge, process operational conditions (Sludge Loading Rate and Organic Loading Rate, Loading rate increase and …), and environment conditions (nutrients, temperature, pH, combination and …).


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