On performing experimental studies on transient states of continuous-flow methanogenic reactors.

One approach to exploring the behavior of microbial cultures during transient conditions of unbalanced growth is to experimentally observe continuous-flow biological reactors which have been subjected to perturbations in the influent flowrate and/or concentration of growth-limiting substrate. Proper interpretation of such experiments requires that appropriate account be taken of reaction stoichiometry, the distribution and abundance of microbial populations within the reactor, and the nonideality of mixing and flow distribution in the reactor. These aspects of proper experimental design are particularly critical when the system of interest involves methanogenic consortia and is not a completely-mixed, suspended-growth reactor.