摘要
为了强化好氧系统中污泥隐性生长对污泥减量的作用,研究了超声波溶胞预处理后污泥溶出物和微观分形结构的变化。探讨了污泥上清液溶解性化学需氧量(SCOD)和污泥粒径(d_(0.5))、比表面积(SSA)、分形维数(D2、D3)等随超声时间和声能密度的变化特征。结果表明,SCOD随声能密度和超声时间增加而增加,能较好地反映污泥的溶解状态。在超声时间5 min、超声脉冲比1∶1的固定条件下,声能密度0.6 W/m L为d_(0.5)和SSA变化的转折点,当声能密度小于0.6W/m L时对d_(0.5)和SSA作用明显,而大于0.6 W/m L时对d_(0.5)和SSA作用微弱。在声能密度0.6 W/m L、超声脉冲比1∶1的固定条件下,1~5 min内SCOD溶出明显提高,超声对污泥溶胞效果较好,5 min后污泥溶胞效率很难进一步提高。皮尔逊相关性分析表明,SSA和D3分别与SCOD呈现显著的相关性。SSA和D3反映了污泥结构的密实程度和溶出状况,因此,可以在线监测微观结构参数SSA和D3来间接反映污泥溶胞效果,从形态学角度为污泥后续处理处置提供前期指导。
In this paper,the author intends to make an investigation of the impact of the ultrasonic lysis pretreatment on the dissolved substances and the microcosmic fractal structure properties of the sludge to be produced. For the above mentioned purpose,we have managed to use the single factor analysis method to enhance the microorganism cryptic growth in the aerobic system,thus having effectively reduced the volume of the sludge under study. At the same time,we have also identified and traced the following indexes,such as the dissolved chemical oxygen demand（ SCOD）,the median particle size（ d_（0.5））,the specific surface area（ SSA）,the 2-D fractal of dimension（ D2） and the 3-D fractal of the dimension（ D3） of sludge,which are likely to vary with the change of the power density and the delay of the reaction time. The results of our investigation and examination have thus shown that the concentration of SCOD in the supernatant tends to increase with the increase of the ultrasonic density and the reaction time prolonging. For example,when the disintegrated degree were to increase by 30. 1% under the ultrasonic condition for 5 min,the 1. 5 W/m L and 1： 1 pulse ratio,the SSA and d_（0.5） would indicate an opposite variation tendency with the change of the ultrasonic power density or/and the reaction time prolonging. And,then,a turning point of SSA and d_（0.5） of the sludge would be coming up at 0. 6 W/m L at an ultrasonic duration of 5 min and 1：1 pulse ratio. Otherwise,if it is below the above mentioned point,the properties of d_（0.5） and SSA would be severely affected by the ultrasonic power density. On the contrary,if it would be beyond the said point,the d_（0.5） and SSA would be badly affected by the ultrasonic power density. Furthermore,we have also found that the optimum ultrasonic duration should be set between 1-5 min at a power density of 0. 6 W/m L with the pulse ratio being 1：1. Moreover,the structural parameters D3 and SSA can be used to screen the effectiveness and e
出处
《安全与环境学报》
CAS
CSCD
北大核心
2017年第6期2348-2352,共5页
Journal of Safety and Environment
基金
国家自然科学基金项目(51108043)
湖南省教育厅重点项目(15A002)
长沙理工大学2015年度大学生创新实验项目
关键词
环境工程学
污泥减量
溶胞预处理
溶出特性
分形结构
超声波
environmental engineering
sludge reduction
lysispretreatment
dissolution properties
ffactal struc-ture
ultrasonic
