Optimization mixing ratio of the brewery waste water sludge and coal as energy source for cement industry and fuel ash effect on the raw material composition

Abstract

Brewery waste water produces sludge with high organic content, which required proper treatment before disposal. The sludge is disposed to landfill creating contamination to the ground water and surface water due to high organic content. Also, it increases the salinity of crops and the environment. Since it has potential for energy production, it can be used in the country's coal-dependent cement industry due to its energy content. The objective of this study was to characterize brewery wastewater sludge and coal, to determine the optimum mix ratio and to see the effect of mixture fuel ash content on raw mix design. Characterization of coal using American Standard Testing Material 2009 and sludge using the World Health Organization method was done and also calorific value with different mixing ratio of coal and sludge determined by a bomb calorimeter in order to find the optimum mix. By using proportionating calculation, determining the effect of mixture fuel ash on the clinker and proportion of raw materials used is done. Brewery wastewater sludge has high moisture content and volatile matter compared to coal. Also, its ash content is higher than coal's. The caloric value of brewery wastewater sludge will not allow for using it without mixing. It is found that 70% coal and 30% sludge is the optimum mix ratio. Its high amount of SiO2 (45%), Al2O3 (14%), and Fe2O3 (11%) makes it possible to substitute some portion of clay and sand stone while our lime feed increases as a result. Since mixture fuel ash content is similar with cement raw materials, brewery wastewater sludge is a good alternative for the cement industry.