Evaluation of the environmental impacts caused by the use of water treatment sludges in the brick industry: case study

Author(s)

Patrícia de Souza Andrade

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Civil, Arquitetura e Urbanismo
• Defense date: 2005-05-16

Examining board members

Dione Mari Morita; Ricardo de Lima Isaac; João Vicente de Assunção

• Advisor: Dione Mari Morita

Abstract

In Brazil, one of the problems which may have a direct effect on the environment is the sludg resulting from sedimentation and filtration at water treatment facilities, as this by-product is ofte discharged directly into the nearest available rivers and streams. When this happens, impacts o the water quality and detrimental effects to the aquatic biota may resulto In this study, residual ITom Cubatão Water Treatment Plant (WTP), in the State of São Paulo, were used to produc bricks in an industry localized in Tatuí (SP). For this purpose, 7 % (dry weight basis) of cIay ma be substituted by sludge. This residual was characterized considering its origin and final use. Afie that, the "Ad-Hoc" Method was applied to evaluate the potential environmental impacts caused b the addition of the sludge into the industrial processo Gathering the interviews with specialists an the literature review, it carne to the concIusion that the environmental impacts were: soil an underground water contamination due to the disposal of sludge in the industrial area before i1 incorporation in the process and because of the inappropriate discharge of the bricks after its us~ contarnination of the industry employees by handling the residual; air contamination as a result c volatile organic compounds present in the sludge and also because of the emissions that OCCUI during the firing process; contamination of people who lives nearby or work at the places wher the bricks are disposed after its use. The impacts were quantified with analysis and tests with an without the use ofthe residual. Risk assessment and mathematical models were applied, the resul1 obtained in both tests (with and without sludge) were compared and the compliance to natiom and international regulations were verified. The conclusions of this study were that the sludg ITom the Cubatão WTP could be incorporated in the ceramic industry ITom Tatuí withOl significant changes in the industrial process, in the brick' s quality or on the environmental impac1 caused by the ceramic processo Beyond that, it was possible to develop a methodology to evaluat the potential use ofthe waterworks sludge in the ceramic industry (AU)