Can hazardous waste become a raw material? The case study of an aluminium residue: a review

Abstract

The huge number of research studies carried out during recent decades focused on finding an effective solution for the waste treatment, have allowed some of these residues to become new raw materials for many industries. Achieving this ensures a reduction in energy and natural resources consumption, diminishing of the negative environmental impacts and creating secondary and tertiary industries. A good example is provided by the metallurgical industry, in general, and the aluminium industry in this particular case. The aluminium recycling industry is a beneficial activity for the environment, since it recovers resources from primary industry, manufacturing and post-consumer waste. Slag and scrap which were previously considered as waste, are nowadays the raw material for some highly profitable secondary and tertiary industries. The most recent European Directive on waste establishes that if waste is used as a common product and fulfils the existing legislation for this product, then this waste can be defined as ‘end-of-waste’. The review presented here, attempts to show several proposals for making added-value materials using an aluminium residue which is still considered as a hazardous waste, and accordingly, disposed of in secure storage. The present proposal includes the use of this waste to manufacture glass, glass-ceramic, boehmite and calcium aluminate. Thus the waste might effectively be recovered as a secondary source material for various industries

Hazardous and industrial waste composition and associated management activities in Caspian industrial park, Iran

“…Waste prevention or minimization should be focused as the priority principle in waste management system (Kim and Long, 2011;López-Delgado and Tayibi, 2012). Manufacturers should reduce generation of hazardous substances and increase use of recycled materials (Koolivand et al, 2014).…”

Industrial aluminum hazardous waste as a new raw material for zeolite synthesis

“…The main crystalline phases present in wastes were determined by X-ray diffraction (XRD) using a Bruker D8 Advance Diffractometer with CuKα radiation, from 5º to 85º 2θ, at a scan rate of 0.02º 2θ, 5s per step, 40 kV and 30 mA. The aluminum nitride content, one of the main components responsible for the waste hazardousness, along with metallic aluminum [2,4], was analyzed by the Kjeldhal method using an automatic steam distilling unit UDK 130 A by Velp Scientifica, and subsequent titration with 1M HCl.…”

“…Zeolites are an extensively studied group of aluminosilicates which are formed by three dimensional networks of AlO 4 and SiO 4 tetrahedra linked together by shared oxygen atoms [5]. The high microporosity present in these materials ("molecular sieve"), the number of documented methods to obtain them and the possibility to introduce variations on their compositions as well as morphologies [6] allow a huge number of applications in interesting fields such as catalysis, ion exchange, chemical separation, membranes, etc.…”

“…In this sense, the high content of aluminum nitride is highly remarkable (ranging between 2 and 24% in weight) because this substance often interacts with the environmental humidity or water releasing ammonia gas in considerable quantities [2,3]. The recent attempts performed to recover this waste are based on the production of viable added-value materials in order to overcome the economical barrier which prevents the implementation of conventional recovery processes [4].…”

The Application of Thermal Solar Energy to High Temperature Processes: Case Study of the Synthesis of Alumina from Boehmite

“…The huge number of researches carried out during the last decades focused on finding effective solution for the waste treatment has allowed some of these residues to become new raw materials for many industries. This achievement ensures saving energy consumption and natural resources, reducing the negative environmental impact and also encouraging the creation of secondary and tertiary industries [14, 15]. …”