水利学报2017，Vol.48Issue(3)：325-333,9.DOI:10.13243/j.cnki.slxb.20160805
农沟底泥和水稻秸秆热解制备生物碳球及其氨氮吸附研究
Preparation of biochar ball with agricultural ditch sediment and rice straw by pyrolysis and adsorption of ammonium
摘要
Abstract
Agricultural ditch sediments were mixed with rice straw according to their ratios of mass,five treatments including no rice straw addition,and mass ratios of agricultural ditch sediment and rice straw were 20∶1,10∶ 1,20∶3,5∶1,then all the samples were made into particle balls,of which the size was 5 mm,finally,they were prepared at 600℃ by anaerobic pyrolysis 4h into biochar balls,and respectively marked as SS-0,SS-50,SS-100,SS-150,SS-200.Elemental analysis,BET-N2 surface area (SA) and porosity analysis,scanning electron microscope,FTIR spectra analysis and Boehm titration were used to characterized their physicochemical properties.Sequencing batch experiments were conducted to investigate ammonium adsorption performance of biochar balls,to build the kinetics models and adsorption isotherm models,and also to research the effects of water temperature on ammonium adsorption.The results revealed that rice straw addition was beneficial to increase the permeability and hydrophilic of biochar balls,and enhanced their mass transfer performance,which were 14％,52％,26％,33％ and 38％ for SS-0,SS-50,SS-100,SS-150 and SS-200 samples,respectively;while the amounts of acidic functional groups were 2.74,2.88,3.71,3.36 and 3.03 mmol· L-1,respectively.The results for fitting experimental data of adsorption process with kinetics models show that SS-0 biochar ball is more aligned with pseudo-first-order kinetic equation,however,the adsorption of ammonium on SS-50,SS-100,SS-150 and SS-200 biochar balls follows pseudo-second-order kinetic equation well,in addition to the intra-particle diffusion,there are other common controlling ammonium adsorption rates of biochar bails.Moreover,Langmuir equation could accurately describe the adsorption isotherms of ammonium on biochar balls.The indexes of Freundlich isotherms equation are all less than 1,which show that the absorptions are endothermic processes,and high temperature is beneficial to the adsorption of ammonium.关键词
农沟底泥/水稻秸秆/生物碳球/氨氮/吸附Key words
agricultural ditch sediment/rice straw/biochar ball/ammonium/adsorption分类
农业科技引用本文复制引用
陈成广,周树烽,胡保卫,徐立红,盛国栋..农沟底泥和水稻秸秆热解制备生物碳球及其氨氮吸附研究[J].水利学报,2017,48(3):325-333,9.基金项目
绍兴市科技计划项目(2014B70041、2014B70049) （2014B70041、2014B70049）
浙江省大学生科技创新活动计划项目(2015R428027) （2015R428027）
