Research paper Microstructure and mechanical properties of cementless construction materials from thermal engineering wastes Vs  evolod A. Mymrin a, * , Marcelo V. da Cunha b , Kirill P. Alekseev a , Haroldo Ponte b , Rodrigo E. Catai a , Cezar A. Romano a a Technological Federal University of Paran a (UTFPR), Curitiba, Brazil b Federal University of Paran a (UFPR), Curitiba, Brazil highlights  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. article info Article history: Received 9 November 2014 Accepted 14 February 2015 Available online 21 February 2015 Keywords: Ceramics industry Fired/unfired wastes Lime production wastes Structures formation processes Mechanical properties Environment protection abstract In order to solve environment problems of ceramics industry new compositions of materials were developed from three types of porcelain production tails e fired wastes (FW), unfired wastes (UW) and wastewater treatment plant sludge (WTPS) e 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 ab- sorption (W A ) 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 (0.71e0.85). 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. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction The strategy of companies to improve their environmental performance is an essential part of their social function, since it not only satisfies their clients' wishes but also improves their re- lationships with environmental control agencies and with society in general. Mere compliance with the minimum standards established by environmental laws is not considered sufficient to maintain a competitive advantage, above all in export markets [1]. The need to recycle industrial wastes is increasing apace due to the rising cost of natural raw materials and effluent disposal, and the need for compliance with environmental legislation. It is estimated that 175 million tons of quarrying waste are produced each year [2]. The consumption of only natural decorative stone materials worldwide is growing annually by 7e9% and now stands at about 700 million m 2 [3]. ANEFA e National Association of Spanish Manufacturers Association of AggregateseAggregates Producers e informed [4] that the consumption of natural aggregates in Spain in 2007 reached the 479 million tons in the construction sector and 72 * Corresponding author. Federal Technological University of Parana, str. Deputado Heitor de Alencar Furtado, 4900, Campus Curitiba, CEP: 81280-340, Ecoville, Par- an a, Brazil. Tel.: þ55 41 3279 4518. E-mail address: seva6219@gmail.com (V.A. Mymrin). Contents lists available at ScienceDirect Applied Thermal Engineering journal homepage: www.elsevier.com/locate/apthermeng http://dx.doi.org/10.1016/j.applthermaleng.2015.02.029 1359-4311/© 2015 Elsevier Ltd. All rights reserved. Applied Thermal Engineering 81 (2015) 185e192