摘要
为提高移动床生物膜反应器中氧传质效率,利用动态溶氧法测定曝气量(0.84～4.2m3/h)、填料填充率(0～30%)、反应器高度(0～0.5m)、溶液中添加表面活性剂十二烷基硫酸钠和电解质NaCl等因素对氧传质系数的影响,结果表明随着曝气量的增大,氧传质系数从0.002 5/s增加到0.066/s,填料固含率在10%时氧传质效果最好;反应器高度主要影响气泡的压力进而影响气液接触面积,随着气泡的上升,氧传质系数从0.011逐渐降低为0.009 6/s;表面活性剂在0～0.015g/L浓度范围内氧传质系数逐渐降低;NaCl通过改变气泡表面的ζ电势和表面张力进而影响氧传质效果,在0～20g/L范围内,氧传质系数随着NaCl浓度的增大而增大.
Aimed at enhancing oxygen mass transfer efficiency in moving bed biofilm reactor,the influences of effect factors on oxygen mass transfer coefficient（KLa） have been studied by dynamic oxygen dissolution method,including intensity of aeration（0.84-4.2 m3/h）,carrier stuffing rate（0-30%）,reactor height（0-0.5 m）,added surfactant（sodium dodecyl sulfate） and electrolyte（NaCl）.The result shows that KLa increases from 0.002 5 to 0.066/s with the increase of aeration intensity and oxygen mass transfer performs the best in 10% carrier stuffing rate.Reactor height affects the gas-liquid transfer area through the change of pressure,leading to KLa gradually decreasing from 0.011 to 0.009 6 s-1 when gas bubble rises to liquid surface.Adding surfactant into distilled water,KLa decreases during its concentration range,0-0.015 g/L.NaCl added plays a significant role in variation of gas bubble＇s ζ potential and surface tension,as a result of KLa increasing in NaCl concentration range of 0-20 g/L.
出处
《武汉大学学报（工学版）》
CAS
CSCD
北大核心
2012年第6期843-847,共5页
Engineering Journal of Wuhan University
基金
山西省留办重点科研资助项目(2010-2)
山西省研究生优秀创新资助项目(20093043)
关键词
移动床生物膜反应器
氧
传质系数
传质机理
气泡
moving bed biofilm reactor
oxygen
transfer coefficient
transfer mechanism
gas bubble
