Numerical research on combustion processes and deposit formation on the deposition probe in the pulverized drop chamber

Abstract

One of the problems associated with the occurrence of fly ash in power boilers is the formation of deposits. Ash deposits worsen the heat exchange on heating surfaces, causing the flue gas temperature to increase, and thus the boiler efficiency decreases. It also increases the pressure of flue gas flow by generating an increase in energy consumption for pumping flue gas. The article presents the results of numerical research on combustion processes and deposit formation on the deposition probe in the pulverized drop chamber for three fuels. The temperature distribution in the chamber was presented in comparison to tests carried out on a real object for three fuels. The temperature and content of O2, CO, CO2 in the outlet plane of the model, as well as the unburnt carbon were compared. According to obtained results, the halloysite addition for biomass contributed to the increase in the content of CO, CO2, and NOx at the outlet of the chamber (respectively an increase by 72%; 5%; and 28%). For biomass, the deposition index was more than four times greater than for coal. The halloysite addition caused the reduction of this index for the sample with halloysite by about 1.3%.