Incorporação de Iodo de estação de tratamento de água em tijolo de argila cozida

Abstract

Water treatment plant (WTP) sludge when improperly disposed in natural water bodies causes environmental contamination and human health risks. The present work proposes the WTP from Manaus water treatment use in the baked clay bricks production by the extrusion method as a viable sustainable alternative to the environment. The baked clay bricks were produced with addition of the following percentage of dried WTP 0.0, 5.0, 10.0, 20.0, 30.0, and 40% and dried clay collected in the ceramic factory from Manaus (Iranduba – AM). The mixtures WTP and clay were burned from 150 to 900 ºC. To avoid cracking in the firing process, temperatures in the 150, 300, 450, 600 and 750 oC temperatures were stable for one hour. Clay, WTP and bricks were characterized structurally by X-ray fluorescence, thermogravimetry, X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR). The physical and mechanical from clay and natural WTP was determined by laser granulometry and Attenberg plasticity indices. In bricks were performed resistence to compression and water absorption tests. The toxicity metal toxic level was available using to leached test whose metal concentrations were determined by inductively coupled plasma atomic emission spectrometry. The results indicated that the bricks obtained in the firing did not present chemical interactions between the components of the WTP and clay. The compressive strength analysis showed that it is possible to replace the WTP in the clay up to 10%, and to comply with the limit value stipulated in NBR15270/1 for conventional brick. The leaching tests suggested the potentially toxic metal immobilization in the brick burning process, thus corroborating with the negative environmental effect the minimization generated by the improper disposal of the WTP.