A review of characterisation requirements for in-line prefermenters : Paper 2 : Process characterisation

The operational factors having a significant effect on in-line prefermentation efficiency include the sludge recycle rate and the subsequent sludge elutriation rate, solids concentrations and retention times. The prefermenter configuration employed is a determining factor, which allows for some degree of operational flexibility. Side-stream and multiple tank systems are superior in this regard and outnumber the use of in-line single tank prefermenters, which are mainly employed due to lower space and capital cost requirements. This paper reviews the basic design and monitoring requirements for in-line prefermenters, to establish simple strategies on which prefermenter evaluations could be based. WaterSA Vol.27(3) 2001: 413-422