响应面法对褐煤微波提质工艺的优化

Optimization of lignite dehydration in microwave field by response surface methodology

本试验利用响应面法（RSM）中的中心组合设计（CCD）法,以微波辐照功率、时间、煤样粒度以及煤样质量作为影响微波脱水速率的因素,优化设计微波褐煤提质工艺。根据CCD中心组合试验原理设计了31组试验,依据回归分析确定各工艺条件对脱水速率的影响,并将微波脱水速率数值作响应面和等值线图。试验结果表明,优选得到的最佳工艺为：煤样粒度组成为0.6～1.25 mm、煤样质量为20 g、微波功率为700 W、干燥时间为4 min。验证得到煤样的脱水速率为4.32%/min,与预测值接近。因此,中心组合设计及响应面法可显著优化褐煤微波提质工艺。

Aiming at optimizing lignite dehydration in microwave field, Central Composlte Design （CCD） and Response Surface Methodology （RSM） were employed to investigate the effects of radiation power, radiation time, coal particle size and coal mass on dehydration rate. Thirty-one experiments were carried out based on the principle of CCD, a quadratic model was developed to evaluate the effects of various process conditions, 3-D response surface graphs and contour maps were presented. The results showed that the optimum coal particle size, coal mass, radiation power and radiation time were 0.6-1.25 mm, 20 g, 700 W and 4 min, respectively. The verified dehydration rate reached 4.32%/min, which was in accordance with the predicted value. Therefore, CCD-response surface methodology could remarkably optimize the process of lignite dehydration in microwave field.