Microstructure and mechanical properties of cementless construction materials from thermal engineering wastes

• Published in: Applied thermal engineering 2015-04, Vol.81, p.185-192
• Main Authors: Mymrin, Vsévolod A., da Cunha, Marcelo V., Alekseev, Kirill P., Ponte, Haroldo, Catai, Rodrigo E., Romano, Cezar A.
• Format: Article
• Language: English
• Subjects: Cements; Ceramics industry; Coefficients; Concrete blocks; Construction materials; Environment protection; Fired/unfired wastes; Lime; Lime production wastes; Mechanical properties; Structures formation processes; Thermal engineering; Wastes
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2015.02.029

In order to solve environment problems of ceramics industry new compositions of materials were developed from three types of porcelain production tails – fired wastes (FW), unfired wastes (UW) and wastewater treatment plant sludge (WTPS) – as the main raw materials of new compositions of cementless building materials. The binder material used here was lime production waste (LPW), i.e., incompletely burned lime. The uniaxial compressive strength of the new materials containing 15 wt% of LPW at one year of age increased up to 14.2 MPa and the materials with 5% LPW content increased up to 8.6 MPa, exceeding the specifications of Brazilian standards for hollow concrete blocks. The water absorption (WA) coefficient of different compositions at the age of 28 days ranged from 17.9 to 24.6%, but this does not affect the values of the water resistance coefficient (0.71–0.85). X-ray diffraction and scanning electron microscopy analyses indicated that the strength of the new materials increases due to the synthesis of amorphous and crystalline compounds. The feasibility of the new materials based on the use of four types of industrial wastes for the production of new building materials with high mechanical properties, which meet the requirements of national standards. •New construction material from three types of Porcelain industry wastes.•Lime production waste was used as binder material.•Uniaxial resistance strength at the age of one year reached 14 MPa.•Structure formation processes were determined by XRD, SEM and EDS methods.•Utilization of industrial wastes has high economical and environment efficiency.