Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

Radiant syngas cooler (RSC) is widely used as a waste heat recovery equipment in industrial gasification. In this work, an RSC with radiation screens is established and the impact of gaseous radiative property models, gas components, and ash particles on heat transfer is investigated by numerical simulation method. Considering the syngas components and the pressure environment of the RSC, a modified weighted-sum-of-gray-gases model was developed. The modified model shows high accuracy in validation. In computational fluid dynamics simulation, the calculated steam production is only 0.63% in error with the industrial data. Compared with Smith’s model, the temperature decay along the axial direction calculated by the modified model is faster. Syngas components are of great significance to heat recovery capacity, especially when the absorbing gas fraction is less than 10%. After considering the influence of particles, the outlet temperature and the proportion of radiative heat transfer are less affected, but the difference in steam output reaches 2.7 t·h–1. The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.