Study of using Calcium Carbide Slag to Prepare Calcium Oxide Briquettes by Molding and Calcination Processes through Taguchi Method

As the disposal of calcium carbide slag (CCS) obtained a by-product during an acetylene gas process creates an environmental problem, this study aimed to use of CCS to prepare calcium oxide (CaO) briquettes for re-use in the production of calcium carbide (CaC2). The influence of binder types (phosphoric acid (H3PO4), molasses, and corn syrup), binder amount (1, 3, and 5%), briquetting pressure (20, 28, and 36 MPa), calcination temperature (800, 900, and 1000 oC), and calcination time (30, 45, and 60 min) on the strength value of CaO briquettes was investigated using the Taguchi approach. The highest compressive strength value of CaO briquettes was found to be 4.05 MPa. The stability and friability values of the final product were 92% and 8%, respectively. ANOVA analysis revealed that the contribution rate of production parameters on the strength value of CaO briquettes were as follows: (i) binder amount, (ii) binder type, (iii) briquetting pressure, (iv) calcination temperature, and (v) calcination time. The optimal production conditions were determined as follows: the amount of binder: 5%, briquetting pressure: 28 MPa, calcination temperature: 900 oC, and calcination time: 60 min. The obtained CaO briquettes provide a required strength value for re-use in the production of CaC2