Characterization of Demolition Construction Waste Containing Asbestos, and the Release of Fibrous Dust Particles

Abstract

This paper focuses on the characterization of demolition construction waste containing asbestos fibers and the monitoring of fibrous dust released from asbestos–cement products (ACPs) during their removal from a three-story industrial building. Asbestos-containing products removal was carried out according to a demolition management system in terms of protection of workers. The results of a chemical analysis, X-ray diffraction analysis, infrared analysis and scanning electron microscopy of demolition waste samples confirmed the same material quality of asbestos–cement (AC) elements used throughout the building. In addition, a MgO/SiO2 ratio corresponding to a serpentine silicate mineral of chrysotile was detected by means of X-ray fluorescence analysis. Also, crystalline phase calcium silicates and calcium carbonates from the cement matrix were identified in the AC waste. The relatively large differences in the elemental analysis between the sample area and the individual points found by energy-dispersive X-ray spectroscopic mapping are related to the composition heterogeneity. The highest content of magnesium occurs where asbestos fibers predominate in the cement matrix. The measured number concentrations of asbestos fibers before, during, and after asbestos–cement products removal were compared to outdoor concentrations. Indoor concentrations of asbestos fibers during the removal of AC materials did not exceed the permissible limit for a working environment (1000 fibers per one m3), except in three spots out of all the working sites inside the building. A relationship between the number and mass concentrations of asbestos dust is shown.

Keywords

• demolition waste
• asbestos-cement material
• chrysotile fibers
• number and mass concentrations of asbestos dust