Operation of a one module hollow fiber submerged type MBR system was
tested in this work. The system was operated at fixed permeate flowrate of 12 l/hr.
The hydraulic retention time of the aeration tank was about 8.3 hr. The mixed
liquor suspended solid (MLSS) concentration was maintained in the range 5000-
5500 mg/l. The results show the workability of this system under Iraqi conditions
without any difficulties. About 85% chemical oxygen demand (COD) removal
was achieved. The value of turbidity is well below 0.61 NTU throughout the