Sustainable food processing systems - Path to a zero discharge: reduction of water, waste and energy

• Published in: Procedia food science 2011, Vol.1, p.1768-1777
• Main Authors: Lee, WangHee, Okos, Martin R.
• Format: Article
• Language: English
• Subjects: food process system; wastewater generation; water and energy consumption; zero discharge food process
• ISSN: 2211-601X; 2211-601X
• DOI: 10.1016/j.profoo.2011.09.260

Since food processing systems consume extensive amounts of water and energy, the food industry has the incentive to reduce water and energy with the goal of developing a zero discharge process that utilizes substantially less water and energy, and generates no waste. The objective of this study is to evaluate water/energy consumption and to propose alternatives that reduce water and energy in the processing of three food products; 1) edible bean, 2) dairy products, and 3) corn masa. Three main approaches were; 1) plant-scale audit data collection to determine energy consumption, 2) laboratory scale experiments to assess product quality changes with a reduction in water and energy usage, and 3) computer-aided simulation to design systems for reduced water and energy consumption and wastewater generation. The results suggest that a zero discharge process is feasible by reducing water and energy. Modifications to the edible bean process reduced water input up to 55% and wastewater generation was decreased up to 91%. In dairy plant, the optimal heat recovery option could economically decrease the boiler fuel requirement by 50 times, and reduce the operating cost to 2.7% of the present cost. The water reuse process in redesigned corn masa process could reduce 90% of wastewater and 55% of water usage compared to the traditional process. The amount of energy required for heating was saved by 70% in the water reuse process. When scaling-up to plant-scale, reusing water could reduce water consumption by 95% and reduce energy requirement by about 80%.