Potential Beneficiation of Readily Available Gold Tailings and Paper Wastes: Development of a New Building Material

Abstract

Gold mine tailings (GMT) generated from gold mining processes are readily available in South Africa. The generated GMT is disposed to the environment by land filling. This occupies considerable land area, which subsequently results into environmental pollution. Numerous industries use paper for a number of applications on daily basis and its generation is inevitable. Unrecycled paper ends up in the landfill, which has a negative impact on the environment, as it is not degradable. This study investigated the blending of GMT and waste paper for the production of building bricks (papercrete). The chemical composition of GMT in terms of elemental, mineralogy and micrograph before and after paper stabilization was examined. Developed composites were cured for 7, 14, 21, 28 days, and the unconfined compressive strength (UCS) and absorption tests were conducted. The results obtained showed an improvement in both the UCS and the water absorption of the bricks with the increment in curing period. The brick cured for 28 days had the highest UCS of 7.76 MPa and the lowest water absorption of 80.43% when compared to the bricks cured for 7,14 and 21 days. The developed papercrete was relatively light in weight; however, they proved not to be suitable for outdoor walls and water logging areas due to their high capability to absorb water.