MODELING THE DYNAMIC-RESPONSE OF AN ACTIVATED-SLUDGE PROCESS

Previously collected data describing aerated synthetic waste water, tr eated in a continuous stirred-tank reactor, are analyzed to understand better the dynamic response to step changes in the dilution rate, D. Comparing a change in D between steady states leads to hysteresis traj ectories on both the graph of specific growth rate, mu, vs limiting su bstrate level (S) and the graph of (S) vs the cell level (X). Qualitat ive differences between the three different monitored cases will be co mpared to simulations of simple models at various dilution level chang es in order to gain understanding of the dynamics of the process.