MATHEMATICAL-MODELING OF COMPETITION BETWEEN SULFATE REDUCTION AND METHANOGENESIS IN ANAEROBIC REACTORS

A structured mathematical model of competition between sulphate reduct ion and methanogenesis in anaerobic reactors has been developed. This model includes multiple-reaction stoichiometry, microbial growth kinet ics, conventional material balances for an ideally mixed reactor; liqu id gas interactions and liquid phase equilibrium chemistry. The model agrees well with existing experimental studies of this competition in anaerobic reactors. Hypothetical computer simulations are presented to illustrate the influence of hydraulic retention rime, SO42-: COD rati o, initial proportion of sulphate reducing and methanogenic bacteria i n seed sludge, sludge retention, hydrogen sulphide inhibition and othe r factors on the outcome of this competition, (C) 1998 Published by El sevier Science Ltd. All rights reserved.