焦煤热溶萃取收率与其特性参数的相关性研究（英文）

Characterization of Coking Coals Using Solvent Extraction at 350 ℃

工业分析和元素分析等传统的煤的基本分析很难与焦煤的特征参数(如最大流动度和最大膨胀度等)建立很好的相关性.所以,本文提出一种新型的煤的热溶萃取法,通过萃取物的收率及性质来预测焦煤的基本特征参数.选取了11种强粘结性和弱粘结性煤,采用热溶萃取法将其分为三种主要组分:低分子量萃取物、高分子量萃取物、萃取残渣.结果表明,不同煤种的三组分收率相差较大,但是不同煤中获得的同一组分性质非常相似.通过对原煤及其各萃取产物的工业分析、元素分析、热解特性分析、热塑性分析及分子量分布分析等详细表征,对两者的性质建立较深入的理解.然后通过数学模拟,获得了三组分收率与焦煤基本特征参数(最大流动度和最大膨胀度)的相关性方程,相关系数分别达到0.79和0.94.可见,焦煤的热溶萃取产物收率与其特征参数有较好的相关性.所以,本文提出的热溶萃取法来预测焦煤的基本特征参数是可行的.

The commonly used coal analyses such as ultimate, proximate analyses etc. have no clear correlation with conventional characteristic parameters of coking coal, e. g. maximum fluidity(MF) and maximum dilatation(MD).Therefore, it has been desired to develop a new coal characterization method from which properties of coking coal can be reasonably predicted. The paper presents, eleven slightly or strongly coking coal were separated into three fractions with different molecular weight size without decomposing the coals by 1-methylnaphthalene(1-MN) extraction at 350℃. For the detailed assistance, the samples were analyzed through, ultimate analysis, thermo-gravimetric analysis(TGA), thermomechanical analysis(TMA), and molecular weight distribution(MWD) measurement for the parent coal and fractions.The possibility of the proposed solvent extraction was a new method for the characterization of coking coal. The results showed that fractions of the extraction yields were significantly different among the coals, and the distribution orders of oxygen between three fractions were also different among the coals, depends on the coal type. However, the differences in the properties of the same fractions obtained from various coals, e.g. pyrolysis, melting and thermoplastic behavior, MWD,were much smaller than the differences in the properties among the three fractions. The regression analysis showed that the significant correlations among the extraction yields, property parameters of fractions or parent coals, and characteristic parameters of coking coal indeed exist. Therefore, the proposed extraction as a new characterization method to studied coking coal.