玉米秸秆粉级配及其孔隙特性试验研究

胡亚风 魏洋 闫亚东 章维要

摘 要：试验研究以不同粒径组成的玉米秸秆颗粒对孔隙结构的影响。采用激光粒度分析仪检测玉米秸秆颗粒的粒度组成，压汞仪检测玉米秸秆颗粒的孔隙结构特性。试验结果表明：把不同粒度的玉米秸秆颗粒进行组合，间断级配颗粒的孔隙结构其孔隙率相近，孔隙分布峰值随75 μm以下颗粒含量的增加，孔隙分布的峰值由21 μm移动到65 μm;对于连续级配的颗粒，孔隙分布相似，孔隙分布的峰值在32 μm，而孔隙率随粗颗粒（200～300 μm）含量的增大，总孔隙率增大近两倍;间断级配组成的颗粒比表面积只有连续级配颗粒的50%。试验研究结果为玉米秸秆粉的应用提供参考价值。

关键词：玉米秸秆;粒度组成;孔隙分布;孔隙率;分形维数;比表面积

中图分类号：S233.1;S216    文献标识码：A   文章编号：1006-8023（2021）01-0111-06

Abstract：The experiment studied the influences of different particle size components of corn stalk on its pore structure. The particle size distribution of corn stalk was measured by laser particle analyzer （LPA）， and the pore structure between corn stalk particles was measured by mercury intrusion porosimeter （MIP）. The experimental results showed that the pore ratio of the discontinuously graded particles was similar， but the peak value of pore distribution moved from 21 μm to 65 μm with the increase of particle content when the particle size was below 75 μm， therefore the peak value of pore distribution was 32 μm for continuously graded particles， when the coarse particle size （200～300 μm） increased， it showed that the maximum pore peak value would increase twice. The continuously graded particles had a double specific surface area than that of discontinuously. The experimental results provide reference value for the application of corn stalk powder.

Keywords：Corn stalk; particle size composition; pore distribution; pore ratio; fractal dimension; specific surface

0 引言

玉米在我国各地都有广泛种植，每年可收集的玉米秸秆资源达2.73亿t，在资源短缺和环境污染的压力下，生物可降解材料的开发与利用已成为学者们研究的热点问题[1]。玉米秸秆主要成分由含氮粗蛋白、碳水化合物（粗纤维）、粗脂肪等有机物和少量的粗灰分质无机物以及水所组成[2]。由于玉米秸秆量大、可利用价值高，目前，玉米秸秆在国民生产各领域有着广泛的应用[3-6]。刘立华等[7]利用玉米秸秆粉做吸附剂，通过批次实验对废水中Cr（Ⅵ）进行吸附行为研究;杨奇亮[8]利用玉米秸秆粉末，通过活化、碳化得到了多孔碳材料（MPC800-10），用来吸附去除废水中的抗生素类污染物;安嫄嫄等[9]研究表明了连续秸秆还田除对土壤总碳、碱解氮和速效钾有显著影响，还能使土壤水稳性团聚体中氮更易富集。……