Yeast industryis one of the most important industries that used as substrate in some food processing
industries. This industry produces large quantities of wastewater that characterized with high
organic impurities due to the use ofmolasses.Several treatment methods such as activated sludge,
moving bed biofilm reactor (MBBR), electrocoagulation, and chemical treatment could be used for
yeast wastewater treatment.In this study the treatment was done on four samples of yeastwastewater
using a scale-pilot consists of 3 tanks followed with sand filter. The 3 tanks were installed on
different levels to feed each tank under gravity. 4 trails were performed as following:theactivated
sludge as a control attempt,integrated fixed biofilm reactor FBR using different media, gravel only
in the second trial, zeolite only in the third trial, and combined between zeolite and gravel in the
fourth trial.Results show that the most efficient trail was FBR with combined media gravel and
zeolite with a HRT 24 h where the removal efficiency of COD,BOD, TSS, TKN, and TP was
94.5%, 96.3%, 97%, 85%, and 83.5%, respectively and the effluents met the acceptable limitation of
law 48 year 1982 for reuse for irrigation purposes.