COST REDUCTION WITH SODIUM SULPHIDE IN EVAQUE THROUGH CHANGING THE PREPARATION CONCENTRATIONS

• DOI: 10.22533/at.ed.3173252324079

• Palavras-chave: sodium sulfide, input costs, willemite flotation, Vazante plant

• Keywords: sodium sulfide, input costs, willemite flotation, Vazante plant

• Abstract:

  The sodium sulfide reagent is of great importance in the willemite mineral beneficiation process in Vazante, in addition to representing approximately 50% of the plant's total cost of inputs. Due to logistical difficulties due to the worsening of the COVID-19 pandemic, sodium sulfide had a price increase that significantly impacted the unit's input costs in 2021. In view of this scenario, the processes area evaluated viable options for reducing of the technical index of sodium sulfide in the Vazante unit and carried out more than 100 flotation tests on the bench to validate the proposals raised. After compiling and analyzing the results obtained, it was decided to carry out an industrial test implementing the new conditions for preparing sodium sulfide and sodium carbonate found (44g/L of sodium sulfide and 32g/L of sodium carbonate). The average consumption of sodium sulfide after project implementation was reduced by 16% compared to the average technical index for the initial period of 2021, demonstrating that the initiative was effective in achieving the proposed objective. This reduction enabled savings with sodium sulfide in the period from June 2021 to May 2022 of around 1 million reais.