Quality study of ceramic bricks manufacture with clay and ashes from the incineration of municipal solid wastes

摘要

This paper presents the main results of the analysis and characterization of bricks manufactured with a clay and ashes mixture in the following proportions: 100:0, 99:1, 95:5, 90:10, 80:20 and 60:40 and calcined at a tempera- ture ranging from 50 to 1100°C. The ashes used for this study were obtained from the bottom and the outlet gases of a Hoffmann-type brick furnace in Tabio, Cundinamarca, Colombia. When the typical coal consumption was substituted in part with incineration of municipal solid wastes (Co-incineration). The clay and ashes bricks were physical and chemical characterized with the following tests: X-Ray diffraction (XRD), Fluorescent X-Ray (FXR), Infra Red Spectroscopy (IRS), Thermogravimetry (TG), Differential Thermal Analysis (DTA), Atomic Absorption Spectroscopy (AAS), Scanning Electronic Microscopy (SEM) and Toxicity Characteristic Leaching Procedure (TCLP) lixiviation tests that were performed according to the EPA 1311 method for the determination of heavy metals. Porosimetry, Cold Absorption, Breaking Load and Strength tests were also carried out to determinate the quality of the bricks. The strength and the breaking load slightly increases with the addition of ashes up to the 90:10 proportion and decreases in the higher ones, whereas the water absorption increases in all the mixtures. This study show that the finished product, manufactured with clay and ashes comply with all the quality standards required in Colombia.