ABSTRACT

Phosphorus is critical for the strength of metals; however, in excess it makes the metal product fragile. This leads to quality complaints and financial losses. Phosphorus is finely disseminated in coal and forms part of the coal structure. Despite the use of a coal facility at Morupule, the final product surpasses the maximum limit of 0.02% phosphorus. Reduction of the phosphorus by convectional coal cleaning processes is a challenge due to the mineral associations with the coal structure. Selective mining is the current implemented option at Morupule to attain the low phosphorus production but it is costly and time-consuming. Hence, the aim of the research to investigate coal leaching as a primary method for phosphorus reduction. Hydrochloric acid at 1 Mol concentration was used for 4 hours at room temperature. Sixty-four percent phosphorus removal was achieved resulting in 0.012% residual phosphorus. To improve the rate of reaction, microwave pretreatment was conducted to further reduce the amount of phosphorus in the coal. The effect of phosphorus reduction using 1000 W single-mode cavity was compared to that of the multimode cavity. The optimum processing parameters were 2 minutes and 3 hours leaching time to yield a residual phosphorus of 0.008%.

摘要

磷对金属的强度至关重要；但是，过量会使金属产品变得脆弱。这会导致质量投诉和经济损失。磷在煤中细小散布，构成煤结构的一部分。尽管在 Morupule 使用了煤炭设施，但最终产品的磷含量超过了 0.02% 的最大限制。由于矿物与煤结构的结合，通过对流煤清洁工艺减少磷是一项挑战。选择性采矿是 Morupule 目前实施的实现低磷生产的选项，但成本高且耗时。因此，本研究的目的是研究煤浸出作为磷还原的主要方法。在室温下使用 1 摩尔浓度的盐酸 4 小时。实现了 64% 的除磷，产生 0.012% 的残留磷。为了提高反应速率，进行微波预处理以进一步降低煤中的磷含量。将使用 1000 W 单模腔的磷还原效果与多模腔的效果进行了比较。最佳工艺参数为 2 分钟和 3 小时的浸出时间，以产生 0.008% 的残留磷。