Monitoring and evaluation of industrial production of fired-clay masonry bricks with 2.5 of phosphatization sludge

摘要

The present study reports the industrial production of fired-clay masonry bricks containing 2.5% phosphatization sludge, the result of a research project carried out in three stages: laboratory, pilot production, and industrial production. After validation of the results of the first and second stages, the local environment authorities issued a permit to produce these bricks on industrial scale and to commercialize them. One of the requirements was the monitoring of the dimensional, mechanical and environmental performance of these bricks at 6-month intervals. This study presents the results of the monitoring of these characteristics in a 5-year period. After each sampling, bricks containing phosphate sludge were measured and submitted to compressive strength, as well to environmental analyses following the official Brazilian standards. The analyses of results of measurements and compressive strength show that the bricks manufactured with 2.5% phosphate sludge were approved for use in the construction industry. Additionally, the fired-clay bricks were classified as a non-inert material. This is not be considered an obstacle to commercializing these bricks, since conventional fired-clay bricks belong to the same class, and present higher levels of solubilized iron and aluminum, above the value defined in the national standard. The results obtained in the environmental, dimensional and mechanical analyses of fired-clay masonry bricks with phosphatization sludge demonstrate that they meet the requirements for production and commercialization.