Abstract

VALDEZ., Silvana K; ORCE, Agustina M.; ABREGU, Blanca A.  and  CANTOLLA, Martin Thames. Preliminary studies for the processing of minerals by solar calcination. Rev. cienc. tecnol. [online]. 2021, n.35, pp.31-40. ISSN 1851-7587.

Certain countries have systems using solar energy on industrial process. The advantage of these systems is to reduce the fossil fuel consumption and carbon dioxide generation, being a sustainable system. There is no background information about the use of non-conventional energy sources applied to pyrometallurgical processes in Argentina. In this paper the feasibility of calcining borates by solar energy was analyzed. The calcination of borates allows to increase their B2O3 content due to the thermal decomposition with the loss of the hydration water. In particular, the calcination of colemanite (calcium borate) occurs around 350-400ºC. A colemanite sample of 70 % purity was calcined using a dish concentrator of 172 cm diameter and a focus depth of 40 cm, the rim angle was 30º. The radiation intercepted by the equipment was determined in kcal/m2 h. Conversion was between 45-72% depending on the environmental conditions. The reaction advancement was measured at different periods of time within an hour. Results show that it is possible to use solar radiation as energy source to calcine and purify colemanite.

Keywords : Colemanite; Calcining; Concentration; Solar Energy.