Incorporation of the Sludge of Sewage Treatment Plant on Ceramic Bricks Manufacture

Treatment processes used in most sewage treatment stations generate as by-product a material named sludge. The amount of sludge grows proportionally with the increase in effluent collection and treatment services, which in turn must accompany population growth. The disposition of waste generated in an environmentally correct and economically viable way is one of the biggest challenges faced by companies that operate sanitation services. The ceramic industry presents a great potential for the use of this waste. The goal of this work was to evaluate the effect of the incorporation of the sewage sludge in the ceramic mass for the manufacture of solid bricks. The water absorption was lower for bricks with 10% sludge, but it increased for bricks with 15% sludge, resulting in products that presented water absorption slightly beyond of the limit of the standard NBR 15270. However, the results are promising because they show that additions of 10% or 15% sludge increased the compressive strength markedly.