Waste management of grits as filler in gypsum plasters: a new approach

The reuse of industrial waste plays a crucial role in avoiding environmental impacts caused by incorrect disposal. Industrial production commonly generates huge volumes of wastes, and also increased costs associated with waste management and landfills maintenance. This study investigates the reuse of grit waste, from the cellulose kraft industry, as filler in gypsum plaster. Samples were prepared in proportions of 100/0, 85/15, 75/25 and 50/50 gypsum/grits and tested at 7, 14, 21 and 28 days. The mechanical resistance with incorporation of up to 25 wt% grit as filler is greater than that recommended in the regulatory standards. Flexural and compression strength tests for 15 wt% of gypsum replaced achieved values of 4.5 and 8.3 MPa, respectively. The manufacture of gypsum/grit is a viable solution for waste management and has great potential for enabling fabrication of gypsum plaster board, a low-cost and more sustainable new material.