化工学报2019，Vol.70Issue(1)：199-206,8.DOI:10.11949/j.issn.0438⁃1157.20180822
高温干燥对褐煤孔隙结构及水分复吸的影响
Relationship between pore structure and moisture reabsorption of lignite dewatered by high temperature drying process
摘要
Abstract
The coal samples dried at different temperatures were prepared by horizontal fixed bed experimental furnace. The specific surface area, pore volume and pore diameter distribution of the coal samples were determined using nitrogen adsorption isotherm (-196℃). The relationship between the pore structure and moisture reabsorption behavior of the lignite samples was investigated using a self-designed reabsorption device. The experimental results show that the N2 adsorption behavior of the semi-coke dried under different temperatures followed the type II adsorption isotherm, and the adsorption loops of the (raw coal and the semi-coke prepared under 600 and 700℃) belonged to type L1, while the adsorption loop of the semi-coke dried at 800℃ showed a transformation tendency from type L1 to type L2. With the increasing of drying temperature, the specific surface area of the dried semi-coke first increased slowly and then decreased and the pore diameter differential corresponded to the mesopore peak showed the same trend. Meanwhile, the pore diameter differential of the macropores remained unchanged. As the drying temperature increased, the fractal dimensions D1 and D2 changed in the opposite trends, and the value of D2 was higher than D1. The moisture reabsorption behaviors of the semi-coke followed the same trend, and the equilibrium moisture content decreased with the increasing drying temperature. The moisture reabsorption characteristics of the semi-coke were closely related to the pore structure, and the equilibrium moisture content had a good linear relationship with the pore volume.关键词
褐煤/干燥/吸附/孔隙结构/分形/复吸Key words
lignite/drying/adsorption/pore structure/fractals/reabsorption分类
化学化工引用本文复制引用
吴渊默,张守玉,张华,慕晨,李昊,宋晓冰,吕俊复..高温干燥对褐煤孔隙结构及水分复吸的影响[J].化工学报,2019,70(1):199-206,8.基金项目
国家重点研发计划项目(2016YFB0600203) （2016YFB0600203）
上海理工大学科技发展项目(16KJFZ094) （16KJFZ094）
