气化炉与辐射废锅接口的数值模拟

Numerical simulation of connection of entrained flow gasifier to radiant syngas cooler

建立了多相流动和传热耦合数学模型,以实验室规模气化装置对模型进行了验证,发现计算值与实验值吻合较好。再通过该模型对气化炉与辐射废锅的接口进行了数值模拟,结果发现:气化炉底部锥体壁面有大量灰渣颗粒积聚,并在锥体上形成热阻较大的熔渣流;废锅拱顶存在长约4 m的回流区,部分颗粒被卷吸回流;此外,增加直段高度、加长冷却管和降低耐火砖厚度都将使接口工作温度下降;提高气化温度和操作负荷则会使接口工作温度上升,且气流流速也将随产气量的增加而提高。

A novel model of multiphase flow and radiative heat transfer combination was established. The results predicted are in good agreement with the lab-scale gasifier experimental data. And this model was used to carry out the unsteady calculation about the connection of entrained flow gasifier to the syngas cooler. It shows that a large number of particles deposite on the cone of the bottom of gasifier and form the slag flow with larger thermal resistance. The vault of radiant syngas cooler （RSC） has a reflux region of 4 m in length and many slag particles are entrained back. Moreover, the temperature of the connection decreases with increasing the straight section of connection and the height of cooling tube and decreasing the thickness of firebrick. The temperature of the connection increases with increasing the gasification operation temperature and the operation load. The velocity of gas flow also increases with the increasing of the syngas production capacity.