Optimization of Fluidized Roasting Reduction of Low-Grade Pyrolusite Using Biogas Residual as Reductant

摘要

Research on the novel technology of fluidized roasting reduction of samples of low-grade pyrolusite using biogas residual as reductant has been conducted. According to the response surface design and the analysis of results, orthogonal experiments have been conducted on the major factors, and the effects on the manganese reduction efficiency have been studied. The maximum manganese reduction efficiency could be optimized to nearly 100%, when the mass ratio of biogas residual to pyrolusite was 0.16:1, the dosage of sulfuric acid was 1.6 times that of the stoichiometric amount, the roasting temperature was 680°C, and the roasting time was 70 min. The results in terms of manganese reduction efficiency of the actual experiments were close to those anticipated by modeling the experiments, indicating that the optimum conditions had a high reliability. Other low-grade pyrolusites such as Guangxi pyrolusite (China), Hunan pyrolusite (China), and Guizhou pyrolusite (China) were tested and all these materials responded well, giving nearly 100% manganese reduction efficiency.