煤气化工艺中灰渣在气流床中沉积行为与煤质组成、温度场、流场间的关系研究

The sample data of the related coal composition – viscosity – temperature are obtained by experiments in this project. On the basis of the sample data, the database for the related coal composition and viscosity are built. The experimental data and the present research achievements (dynamic simulation results of the Shell gasifier) are combined, then the existing viscosity model can be improved and the general viscosity model for industrial application can be established. Furthermore, the effects of coal composition, viscosity of coal ash and slag, heat radiation in the internal of gasifier and temperature field of the internal of gasifier on the deposition of ash and slag are investigated. The aim of these is to model the relationship of coal composition, temperature field and fluid field with deposition of coal ash and slag. The theoretical guidance for operation of the entrained reactor for coal gasification can be provided and stable running of the plant can be achieved by the model.

本项目拟通过实验获取主要工业用煤的组成-粘度-温度的样本数据，采用课题组已购的高温粘度计对煤灰样进行测量，其目标是建立主要工业用煤煤质、粘度等理化性质的数据库，并结合实验数据及目前的研究基础--气化炉动态仿真模拟结果，对现有粘度模型进行改进，建立符合气流床煤气化工业过程并具有一定适用性的粘度模型。在此基础上，考察煤质组成、灰渣粘度、气化炉内热辐射、温度场对灰渣沉积的影响规律，借助于已有的研究基础和本课题组已购的流场模拟软件ANSYS及相对应的实验数据，目标是获得符合气流床气化工业过程的煤质、温度场、流场对灰渣沉积过程影响的数学描述，为工业粉煤气流床气化反应器操作过程中的灰渣沉积控制提供理论依据的操作指导，达到使气流床煤气化反应炉长周期平稳运行的目标。

本项目通过四年的研究，完成了典型煤质的收集及其理化性质的分析，建立了煤灰渣理化性质的数学模型，并在此基础上对反应器内部的温度场、流场及浓度场进行模型分析研究，确定了煤灰渣沉积过程的影响因素，并对气流床反应器内飞灰夹带的因素进行分析，探讨了煤气化气流床反应器内部飞灰夹带量的有效控制手段，建立了气流床反应器内部旋流强度的定量指标—旋流数，该准数为多喷嘴煤气化气流床反应器的设计提供了相应的理论依据。