ABSTRACT

The self-heating of coal due to oxidation potentially leading to its ignition is called “spontaneous combustion.” The liability of coal to undergo spontaneous combustion for selected coal obtained from the Witbank Coalfields was examined using different spontaneous combustion tests. The simple indices [crossing point temperature (XPT) and Stage II Slope] obtained from differential thermal analysis and composite indices [FCC (Feng, Chakravorty, Cochrane) and Wits-Ehac Indices] were used to examine the liabilities of 30 coal samples. Two characteristics produced from a differential thermogram (XPT and Stage II Slope) were evaluated as indicative of the liability of coal to self-heat. This study compared the results of various spontaneous combustion tests to assess the liability of coal to undergo spontaneous combustion. It was found that these simple indices provide inconsistent predictions of spontaneous combustion liability, while the composite liability indices provide more reliable results than the simple indices. The physicochemical properties of the samples were found to have impacts on the liability indices and vary from one sample point to another.

摘要

煤由于氧化而自热可能导致其着火被称为“自燃”。使用不同的自燃测试来检查从 Witbank 煤田获得的选定煤的自燃倾向。从差热分析和综合指数[FCC（Feng、Chakravorty、Cochrane）和Wits-Ehac 指数]获得的简单指数[交叉点温度（XPT）和阶段II斜率]用于检查30个煤样的负债。从差示温谱图（XPT 和 Stage II Slope）产生的两个特征被评估为煤对自热的倾向的指示。本研究比较了各种自燃试验的结果，以评估煤发生自燃的可能性。发现这些简单指数提供的自燃责任预测不一致，而复合责任指数提供的结果比简单指数更可靠。发现样品的理化性质对责任指数有影响，并且从一个样品点到另一个样品点不同。