화학공학소재연구정보센터
Chemical Engineering Communications, Vol.173, 79-90, 1999
Characterisation of cake compressibility in dead-end microfiltration of microbial suspensions
Culture broths of Saccharomyces cerevisiae and Kluyveromyces marxianus var marxianus NRRLy2415, suspensions of rehydrated active dry bakers yeast and suspensions of calcium carbonate were filtered in dead-end mode at pressures below 200 kPa. In the case of all the microbial suspensions, the specific cake resistance was found to be a linear function of pressure. Cake compression was found to be reversible or weakly irreversible with respect to changes in pressure, i.e., the specific resistance measured at a given pressure was only weakly dependent on whether the filter cake had previously been exposed to higher pressures. The greatest irreversibility effects were obtained with unwashed active dry yeast suspensions, consistent with the breakdown of cell aggregates in these suspensions. The specific cake resistance of calcium carbonate suspensions was found to be a non-linear function of pressure. The compression of calcium carbonate cakes was irreversible, consistent with the breakdown of the large number of particle aggregates in these suspensions.