摘要
[目的]富油煤热解重质焦油制备石墨化泡沫材料是富油煤资源高值化利用的方式之一.[方法]为探究不同反应条件与泡沫炭性能的联系从而制备高性能泡沫炭材料,以重质焦油制备中间相沥青为前驱体,采用高温自发泡法制备泡沫炭.考察不同反应温度、升温速率和反应压力对煤焦油基泡沫炭性能的影响,最后进行Box-Behnken响应面设计实验建立二次多项回归方程,揭示泡沫炭孔隙率、导热系数与反应条件的关系.[结果和结论]结果表明:反应温度、升温速率和反应压力对煤焦油基泡沫炭性能有显著影响.泡沫炭孔隙率的最优值为72.8%,对应的条件为温度559℃、压力 0.48 MPa、升温速率 9℃/min,影响因素温度>压力>升温速率;泡沫炭导热系数最优值为0.219 W/(m·K),对应的条件为温度 549℃、压力 2 MPa、升温速率 3.9℃/min,影响因素升温速率>压力>温度.经过响应面模型优化后的工艺参数可制备具有良好孔隙率及导热性的泡沫炭材料,为提升富油煤热解效率提供新方案.
Abstract
[Objective]Preparing graphitized foam materials using heavy tar produced by the pyrolysis of tar-rich coals plays a significant role in the high-value utilization of tar-rich coal resources.[Methods]This study aims to prepare high-performance carbon foam materials by investigating the relationships between various reaction conditions and carbon foam performance.First,using mesophase asphalt prepared with heavy tar as the precursor,carbon foams were de-veloped via the high-temperature self-foaming method.Then,the effects of different reaction temperatures,heating rates,and reaction pressures on the performance of coal tar-based carbon foams were examined.Finally,quadratic multinomi-al regression equations were established using Box-Behnken response surface experiments,revealing the relationships of the porosity and thermal conductivity of the carbon foams with various reaction conditions.[Results and Conclusions]The experimental results indicate that the reaction temperature,heating rate,and reaction pressure significantly influ-ence the performance of coal tar-based carbon foams.The optimal porosity of the carbon foams was 72.8%,correspond-ing to a temperature of 559℃,a pressure of 0.48 MPa,and a heating rate of 9℃/min.In this case,the effects of these reaction conditions decreased in the order of temperature,pressure,and heating rate.The optimal thermal conductivity value of the carbon foams was 0.219 W/(m·K),corresponding to a temperature of 549℃,a pressure of 2 MPa,and a heating rate of 3.9℃/min.In such an instance,the effects of these factors decreased in the order of heating rate,pres-sure,and temperature.The process parameters optimized using the response surface model enable the preparation of car-bon foam materials with high porosity and thermal conductivity,providing a new solution for enhancing the pyrolysis ef-ficiency of tar-rich coals.
基金项目
宁夏回族自治区重点研发计划项目(2023BEG02058)
陕西省技术创新引导专项(基金)项目(2022QFY06-04)
陕西省"两链"融合重点专项项目(2023-LL-QY-05)
陕西省自然科学基础研究计划项目(2019JL-01)
国家科技期刊平台
NSTL
万方数据