基于褐煤物性变化特征与界面稳定机理的振动热压脱水多能量场输配机制

There are large reserves of lignite in China. But the large scale utilization of lignite is limited by the high moisture content of lignite. It is significant to develop the lignite dewatering technologies with good economy and high efficiency. The mismatching of the energy input and the coal properties is the important reason of high energy consumption of dewatering and the high liability of dusting, reabsorption and spontaneous combustion of dewatered lignite. In vibration mechanical thermal expression process, the efficiency of dewatering is enhanced by the coordination of multi energy fields, the lignite is briquetted, and the liability of reabsorption and spontaneous combustion are inhibited. This project will focus on the mechanism of coal properties variation and interface stability during affected by temperature field, mechanical force field and vibration force field during lignite dewatering by vibration mechanical thermal expression process. Base on the model of lignite physical structures and interface properties, the relationships between coal properties and dewatering will be studied, and the mechanism of the coal properties variation under multi energy fields will be discussed. Based on the analysis of the effect of coal properties on the liability of reabsorption, spontaneous combustion and briquette properties of dewatered lignite, the mechanism of the interface stability of lignite will be discussed. The multi energy fields will be optimized based on the judgment mechanism of dewatering efficiency and interface stability. The mechanism of multi energy fields control based on coal properties variation and interface stability during lignite dewatering by vibration mechanical thermal expression process will be established. This project is valuable for the theoretical researches of lignite efficient dewatering.

我国褐煤资源储量大，但较高的水分含量制约了褐煤大规模利用，开发经济高效的褐煤脱水技术具有重要意义。能量输入方式与动态变化的褐煤物性不匹配是导致脱水能耗高、脱水后褐煤易复吸、自燃、粉化等问题的重要原因，振动热压脱水过程能够在多能量场协同作用下提高脱水效率，形成界面性质稳定的型煤，有效抑制复吸、自燃、粉化。本项目将围绕褐煤振动热压脱水过程中温度场、机械压力场、振动力场协同作用下褐煤物性变化特征与界面稳定性机理展开研究，从构建典型褐煤结构特征的物理空间与界面性质模型入手，研究水分脱除与褐煤孔特征、官能团等物性变化的内在联系，探究多能量场对褐煤物性变化的协同作用；研究褐煤物性变化对复吸、自燃、型煤特性的影响，揭示褐煤界面稳定机理；基于脱水过程能效与界面稳定性判别进行多能量场优化，构建基于褐煤物性变化特征与界面稳定机理的振动热压脱水多能量场输配机制。本项目的实施对褐煤高效脱水研究具有重要理论价值。

我国褐煤资源储量大，但较高的水分含量制约了褐煤大规模利用，开发经济高效的褐煤脱水技术具有重要意义。本项目研究了不同温度、机械压力与振动条件下振动热压与热压过程对褐煤中水分的脱除效果，并分析了脱水后煤样的物理化学结构变化，探讨了温度场、机械力场与振动力场对脱水过程的作用机理。研究了褐煤在不同实验条件下脱水后获得的型煤的强度，分析了实验条件与煤质特性对振动热压与热压脱水过程中褐煤无粘结剂成型的影响。探索了热压工艺对褐煤的自燃特性和水分复吸特性的影响，找出了影响褐煤自燃的主要因素和抑制方法，研究各提质样品在不同环境温湿度下的水分复吸规律，为有效预防和抑制脱水褐煤的自燃和水分复吸问题提供理论支持。基于温度场、机械力场、振动力场对于脱水过程作用机理的分析，建立了褐煤振动热压脱水过程数学模型，并将振动热压脱水过程应用于气化细渣分级脱水，实现脱水过程的节能降耗。