Study of perspective compositions for casting copper anodes

Casting of copper into anodes is final stage of copper pyrorefining. Currently at Copper plant of Norilsk Nickel MMC PJSC in order to protect casting form from rapid wear and prevent welding of anodes to it during casting, the casting forms are filled with a solution of heat-resistant coating based on silicon dioxide. The coating layer remaining on the anode results in slime yield increase at the stage of electrolysis, as well as complication of further slime processing. In this regard, the purpose of this study was to select a coating that prevents the possibility of anodes contamination with silicon dioxide. Thus, the material described in the study and used as a refractory filler of the coating that does not contain slag-forming components in its composition is graphite. Since graphite is poorly wetted, there is a problem of creating a slurry with graphite distributed evenly over the entire volume. Aqueous solutions of polyvinyl alcohol, lignosulfonate and hide glue are used as a binder in the study. According to research, formation of gas porosity and irregularities of the obtained anodes is noted when aqueous solution of lignosulfonate and hide glue are used as a binder. In addition, according to research, accumulation of mineral component in the refractory filler composition is noted when using an aqueous solution of lignosulfonate. When using hide glue as a binder, a stinking odor is noted, as well as increased consumption of this type of binder. As it follows from this study, polyvinyl alcohol-graphite combination has the optimal properties as a refractory paint. In order to optimize the process parameters for application of a binder and a refractory filler, studies of sedimentation stability, as well as the hiding power of the recommended non-stick paint, were carried out.