Brewery plants produce a large quantity of wastewater which contains high concentrations of organic pollutants, low concentrations of nutrients, and have a large variation in these parameters. In particular, brewery effluents are generally characterized by high COD (BOD5) and TSS concentrations and wide variations in flow and strength. This results because the effluent stream is made up of the combined discharges of the brewing and packaging sections, whose production rates vary independently of one another. The packaging process produces a high flow, high pH, weak waste composed primarily of spilled beer and caustic bottle cleaning solutions, while the brewing process produces a low flow, neutral pH, high strength alcohol-carbohydrate-protein waste.
In general, pH of the effluent is a function of production activities and may range from pH 7 to 12. However, within a few hours (7 to 16 hours) hydrolysis and anaerobic activity usually reduces the pH to about 4 to 8 since the effluent has a poor buffering capacity. This pH reduction is a function of the carbohydrate concentration which reflects the brewing production rate. Therefore, brewery wastewater tends to be very difficult to treat, this is why the production process of each client must be analyzed individually and carefully in order to obtain the desired results.
Anaerobic treatment is now becoming a popular treatment method for brewery wastewater, because of its effectiveness in treating high strength wastewater and because of its economic advantages. Developed in the Netherlands in the late seventies (1976-1980) by Prof. Gatze Lettinga - Wageningen University, UASB (Upflow Anaerobic Sludge Bed) reactor was originally used for treating wastewater from sugar refining, breweries and beverage industry, distilleries and fermentation industry, food industry, pulp and paper industry.
For a better description on how the UASB reactor works, please refer to our dedicated page on the section “Technologies”: http://www.idrosistem.com/page/technologies/uasb-53