Increasing the energy efficiency of buildings has become very pertinent currently. This will be implemented by employing eco-friendly materials such as foam glass. Glass foaming is a process that depends strongly on the foaming mechanism and the initial composition of the mixture. This study deals with the investigation of foam glass properties consisting of recycled bottle glass material, CRT glass and aluminium dross. Experiments were carried out to investigate the thermal behaviour, optimal foaming temperature, density, water absorption, thermal conductivity and compressive strength of the foams. Microstructure and cell size distribution was analyzed as well. Effect of the CRT glass and the aluminium dross on the properties of the foams was evaluated in this paper. Adding aluminium dross decreased the foaming temperature, increased the foaming height and enhanced the compressive strength of the foam glass.

The salt content in the secondary dross obtained beside the recovered aluminium by the hot processing of the primary melting dross hinders further utilization of this material. Secondary dross samples obtained from the industrial hot processing of the primary dross generated by the melting of aluminium alloy scrap were leached with water at room temperature with different Liquid/Solid (L:S) ratios. Vessel filling (the relative volume occupied by the sludge) in the shaking bottles required further consideration in the interpretation of the results. Samples taken regularly within 15 minutes during vigorous shaking showed that NaCl and KCl can be dissolved almost instantly, and completely irrespective of the parameter settings. However, the fluoride additive (CaF2) has a complex behaviour. The results suggest its relation to some side reactions indicating also the conditions of the hot process producing the examined material. The results suggest that the salt content of the secondary aluminium dross can be lixiviated within a 2 -4 minutes virtually completely, but the L:S ratio and the a vessel filling have to be coordinated. At the lowest L:S ratio examined of 1.0, a vessel filling of max. 11% should be observed to achieve this fast salt dissolution. The same dissolution rate can be reached with double the vessel filling (i.e. smaller unit) if the L:S is also increased in this ratio.

Aluminium dross is a hazardous industrial waste generated during aluminium production. It contains metallic oxides of aluminium and magnesium, other phases (aluminum nitride), and residues of fluxes and salts from the melting process of aluminium. Discarding this by-product is considered an environmental and economic challenge due to the high reactivity of dross with water or even air humidity. After removing the hazardous components from the as-received dross, one of the optional approaches is to incorporate the treated dross into construction materials. Dross is applied in several types of research as a secondary raw material source for alumina, clinker, cement or glass-ceramic production, but only a few papers focus on the usage of dross as a foaming agent for foams. Even fewer research are reported where dross was applied as a basic component of foam glasses. In this work, foam glasses were produced completely from waste materials: Aluminium dross, container (SLS) glass, and cathode ray tube (CRT) glass. The research holds several specificities, i.e., combining two industrial waste materials (CRT glass and dross), and adding an increased amount from the wastes. The physical and mechanical characteristics were examined with a special focus on the effect of the foam glass components on the microstructure, density, thermal conductivity, and compressive strength.

In this research, alumina-zeolite composite materials were synthesised by mechanical activation and oxidation sintering technique. A comprehensive examination of the microstructure of the starting raw materials and the sintered ceramic specimens have been studied via X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover, several properties were investigated such as volume shrinkage, density, porosity, weight loss and water absorption based on the compositions of the composite specimens, sintering temperature, and microstructure. The authors have found that the raw material compositions and the sintering temperature have great influence in the microstructure and the characteristic of the final prepared ceramic specimens.