Feasibility of Bioenergy Production from Ultrafiltration Whey Permeate Using the UASB Reactors

Abstract

Cheese whey is a by-product generated during cheese manufacturing. The disposal of whey is problematic because of its high COD (Chemical Oxygen Demand) (about 50,000 mg L-1 80,000 mg L-1), low solids content (5% DM), low bicarbonate alkalinity and its tendency to get acidified very rapidly (Aktas et al., 2006; Gonzalez Siso, 1996; Venetsaneas et al., 2009). In 2008, Poland produced almost 1123 thousand tonnes of whey (Agricultural Market Agency [ARR], 2009). Traditionally, cheese whey has been used to feed animals, but redistribution of whey to farmers is very expensive. Moreover, lactose intolerance of farm animals also limits the use of whey in feeding (de Glutz, 2009). Since large quantities of whey are produced (about 9 kg of whey in the production of 1 kg cheese) (Zafar & Owais, 2006), there is an increasing concern as how it can be efficiently and cost-efficiently processed without adversely effecting the environment.