Bulgur cooking process: Recovery of energy and wastewater

In this study, the recovery of energy and water from the wastewater of the bulgur cooking process was investigated, including; i) recovery of the wastewater from the initial cooking process using filtration, centrifugation, a packed-filtering column (containing sand, activated carbon and resin) and ultraviolet-light (UV), and ii) the re-use in the subsequent cooking process by mixing with fresh water. Dissolved Oxygen (DO), 5 days-Biochemical Oxygen Demand (BOD5), pH, turbidity, conductivity, total solid content and Brix were measured to determine the effects of the wastewater treatment operations. It was found that these treatments were significantly (P ≤ 0.05) effective in the reduction of the BOD5 values from 429.5 to 93.7 mg/L. The total solid content, Brix, conductivity and turbidity values decreased. The energy requirement to heat up the water for cooking may be reduced to 57% of current energy usage. It was found that the re-use of wastewater may be possible for the subsequent cooking operations.Graphical abstract

Source: Journal of Food Engineering - October 11, 2019 Category: Food Science Source Type: research