According to characteristics of microbial growth, anaerobic treatment proce
sses can be classified in two major groups: fixed-film and suspended growth
. In this study, operational conditions for both fixed-film (Downflow Stati
onary Fixed Film, DSFF and Upflow Anaerobic Filter, UAF) and suspended grow
th (Thermophilic Anaerobic Contact Reactor, TACR) model anaerobic reactors
are presented and chemical oxygen demand (COD) removal efficiencies of thes
e systems are compared.