Characteristics of particulate matter generated in pressurized coal combustion for high-efficiency power generation system

Abstract

Characteristics of particulate matter in pressurized coal combustion for high-efficiency power generation system are investigated by using the percolation model and the results are compared with experiments performed using drop tube furnace facilities (DTF). The results show that conversion for Plateau coal (high volatile matter and low ash contents) rises earlier than that for Newlands coal (low volatile matter and high ash content). For both coals, volatile consumption rate increases with increasing the gaseous temperature, whereas the char combustion rate increases with increasing both the gaseous temperature and the pressure. At the char-combustion-dominant stage after devolatilization, the characteristics of the particulate matter such as specific surface and porosity area are not affected by the gaseous temperature, but they are affected by the pressure and the coal properties. These results are of general agreement with the experiment by DTF and hence the present percolation model is valid for the prediction of the characteristics of the particulate matter in coal combustion.