The aim of the present study was the treatment of industrial starch wastewater to be used for irrigation using a technology that is robust and very simple to operate with minimum energy consumption. In order to achieve this important objective, the Innovative Aerobic Technology for wastewater Treatment scheme was investigated. The Innovative Aerobic Technology consisted of a down-flow hanging sponge (DHS) reactor. The Innovative Aerobic Technology system was fed continuously with the Anaerobic Baffled Reactor (ABR) effluent. The DHS reactor was operated at different hydraulic retention time (HRT) of 19.2 h (Run 1), 12.8 h (Run 2), and 6.4 h (Run 3). The average removal values of total chemical oxygen demand (CODt), soluble chemical oxygen demand (CODs), biological oxygen demand (BOD5), total suspended solids (TSS), and total nitrogen (TN) were 57.1%, 63.0%,49.8%, 46.6%, and 68.1%, respectively, for Run 1, 59.0%,47.6%, 46.3%, 55.1%, and 59.7%, respectively, for Run 2, and 53.0%, 50.0%, 58.0%, 31.9%, and 74.5%, respectively, for Run 3. The available data proved that the DHS reactor can deal with higher organic loads. The performance of the DHS reactor was very suitable for carbonaceous organic matter and nitrogen removal and even for wastewater with a high organic loading rate (OLR) of 41.5 kg COD/m3d.
