中心提升管内循环流化床生物质气化装置的关键是合理控制物料循环量。自行设计并搭建了中心提升管内循环流化床冷态试验台,在小型试验台上就运行参数对颗粒循环流率的影响进行了试验。试验结果表明:颗粒循环流率随着提升管风速或鼓泡床风速的增加而增加,并且当提升管风速或鼓泡床风速分别增加到一定程度时,颗粒循环流率增加趋于缓慢。在试验基础上,建立了颗粒循环流率预测模型,得到的模型预测值与试验值吻合良好,预测相对误差小于±10%,即在一定操作条件下,验证了该模型的正确性。
To rationally control the circulating flow rate of the bed material is the key to a biomass gasification device with a circulating fluidized bed inside a central elevating tube.A cold-state circulating fluidized bed test stand inside a central elevating tube was independently designed and set up.On this small-sized test stand,tested was the influence of the operating parameters on the particle circulating flow rate.The test results show that the particle circulating flow rate increases with an increase of the air speed in the elevating tube or the bubbling air speed on the bubbling bed.Furthermore,when the air speed in the elevating tube and that on the bubbling bed increase respectively to a certain degree,the increase of the particle circulating flow rate will tend to slow down.On the basis of the tests,a model for predicting the particle circulating flow rate was established.The prediction values obtained by using the model in question are in good agreement with the test ones.The relative error of the prediction is less than ±10%,proving that the correctness of the model in question is verified under certain operating conditions.