Leaching of Chromium in Red Ceramic Monolith by Immersion and Irrigation

摘要

The use of waste to improve sustainability of construction materials has increased in recent years. However, in Brazil no specific official standard has been issued on the solidification/stabilization (S/S) technique for construction materials. Similarly, no leaching methodology to evaluate products that include waste, under common use conditions, has been developed. As a result, both waste and products developed based on the S/S technique are assessed following the same official standard, which considers the landfill as the only final disposal condition. This study presents a leaching methodology to analyze the S/S approach in construction materials. Red ceramic sample blocks were manufactured with the addition of 0.05% Cr_2O_3. Two leaching approaches were conceived: immersion and irrigation. Tests were carried out in four 7-day cycles. Total experimental time was shorter than the period stipulated in a Dutch standard for this purpose. The results had low coefficient of variation and proved the usefulness of the technique to simulate intense and prolonged contact with a leaching agent, as in floods, and exposure to acid rain.