热水解超声组合预处理对污泥厌氧消化产气潜力的影响研究

针对城市污泥厌氧消化由于融胞困难所导致的消解速率低、产气量低等问题,采用热水解与超声组合的方法对污泥进行预处理,考察经预处理后污泥融胞效率的变化及对厌氧消化产气潜力的影响.结果显示,热水解与超声波组合工艺对污泥的破胞作用明显,在30 min热水解与0.53 W/mL超声声能密度组合工艺反应60 min条件下,相对于处理前污泥,预处理后污泥溶解性COD(SCOD)溶出率可提高41.6％,蛋白质增加值达282.7 mg/L,污泥厌氧消化的产气潜力显著增加;30 min热水解分别与0.53、0.33 W/mL超声声能密度组合工艺对污泥破胞效率的差异不大;随着超声时间的延长,在组合预处理工艺前20 min内SCOD的溶出速率较慢,20260 min时溶出速率逐渐提高.试验结果可为城市污泥厌氧消化预处理工艺的选择提供一定的理论依据.     

利用缫丝废水处理过程中产生的微生物蛋白制备复合氨基酸

以缫丝废水处理过程中产生的微生物蛋白为原料,采用正交实验分析了采用酸水解、超声波水解、微波水解制备复合氨基酸的最佳工艺条件,并对比了最佳工艺条件下的水解效果.结果表明,酸水解的最佳工艺条件是水解时间2.Oh、固液比(体积比,下同)5∶1、硫酸质量分数50％、水解温度100℃,超声波水解的最佳工艺条件是水解时间0.5h、...     

气浮法对矿区洗浴污水中洗涤剂处理及回用研究

通过不同方案的对比试验,确定了矿区洗浴污水处理及回用的工艺,重点解决了阴离子合成洗涤剂对水质的影响,为矿区洗浴污水回用提供一项可行的方案。     

超声技术降解对氯苯酚的研究

研究了超声降解对氯苯酚(4-cp)溶液的规律和超声波对其降解效果的影响因素。实验结果说明溶液的初始浓度、辐射时间、作用频率和作用功率、pH值等因素对对氯苯酚降解效果有明显影响。实验的最佳方案是:溶液的初始浓度为50.30mg/L、超声辐射时间为360min、作用频率为59kHz和作用功率为90W。     

Evaluation of the spontaneous combustion characteristics of coal of different metamorphic degrees based on a temperature-programmed oil bath experimental system

Research on the micro- and macrocharacteristics of different metamorphic degrees of coal helps improve the control and protection techniques used during spontaneous combustion. Nine coals with different properties were thoroughly investigated in this study. Fourier transform infrared spectroscopy and a self-designed temperature-programmed oil bath experimental system were adopted to analyze the molecular structure and macrocharacteristic parameters of the spontaneous combustion of coal. Additionally, the influence of particle size on spontaneous combustion was considered. Various functional groups were employed as microcharacteristic parameters to capture the principal active groups in oxidation. The gas production rate, oxygen consumption rate, gas concentration, heat energy release rate, and characteristic temperatures were evaluated as macrocharacteristic parameters to investigate the changes in coal during oxidation. The results establish that the microcharacteristics of coal molecules determine the degree of spontaneous combustion based on intrinsic properties and that changes in the macrocharacteristics of the spontaneous combustion of coal reflect the microstructural changes. The contents of the hydroxyl groups, carbonyl groups, alkyl ether and aryl ether in the coal molecules gradually decrease with the metamorphic increase. Oxygen-containing functional groups have higher reactivities and easily react with oxygen, causing the macroparameters, such as the oxygen consumption rate, the gas generation rate and the heat energy release rate, to consistently decrease with the increase of the metamorphic degree. Small-particle-size coal molecules have more active aliphatic hydrocarbons, oxygen-containing functional groups and a larger specific surface area, increasing the chances of adsorbing the oxygen of active groups and promoting the reaction between coal and oxygen. The experimental results indicate that coal samples with higher metamorphic degrees or larger sizes exhibit lower tendencies toward spontaneous combustion. Evaluation of the spontaneous combustion of coal based on a temperature-programmed oil bath experimental system is of great practical importance for preventing the spontaneous combustion of coal during storage, processing and utilization and can serve as a convenient reference for production safety in mining applications.     

Removal of copper from a copper sulphate solution using an ultrasonic-electrolysis process

The application of ultrasonic-electrolysis process for the removal of copper is studied.In the ultrasonic field cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution.Thus increases metal deposition on the cathode surface.The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution.     

柠檬酸对重金属复合污染土壤的浸提效果研究

以浙江富阳某炼铜厂附近受Cd、Cu、Pb和Zn复合污染的土壤为研究对象,采用振荡、静置和超声3种不同浸提方式,通过研究柠檬酸在不同浸提方式下对重金属的去除效果,筛选出最佳柠檬酸浓度、处理时间及功率,并采用Tessier连续提取法分析浸提前后4种重金属形态变化.结果表明,柠檬酸对4种重金属均具有较好的去除效果,其中对Zn的去除效果最好,Cd的去除效果最差,而Cu和Pb的去除效果相当.Pb和Zn的去除率均随着柠檬酸浓度的增加而增加,但增幅随之减小,Cu的去除率则先增加后基本保持不变,而Cd的去除率变化不明显.综合考虑成本和浸提效果后,选用0.2 mol·L-1柠檬酸浸提2次为最优条件,最佳振荡时间和静置时间分别为4 h和24 h,最佳超声时间和功率分别为30 min和500 W.柠檬酸能够在很大程度上改变土壤中重金属的形态分布,主要去除以可交换态和碳酸盐结合态形式存在的Cd及以碳酸盐结合态和铁锰氧化物结合态形式存在的Cu、Pb和Zn.通过对比3种浸提方式,在同等去除效果的前提下,静置浸提相比振荡浸提需要更长的时间,而将超声波应用于重金属污染土壤淋洗,所需时间较少,因此,超声波辅助浸提土壤中重金属是可行的,具有良好的应用前景.     

超声波辅助提取雨水管道沉积物中磷的存在形态

在SMT法的基础上采用超声波技术对实验条件进行优化,用于雨水管道沉积物中磷的提取。通过对提取时间、提取温度等影响提取效率的因素进行分析,确定了提高闭蓄态磷提取效率的条件,从而建立了管道沉积物中磷形态分析的最佳条件。在确定的最佳提取条件下对北京城区雨水管道内沉积物中磷的存在形态进行提取,并对不同形态磷的污染水平和分布状况进行分析,结合环境状况等因素对不同形态磷的污染特性进行了综合研究。     

超声波技术处理微污染水的实验研究

通过实验,对使用超声波技术处理微污染水的效果、机理进行了初步研究,实验结果表明,超声波对微污染水的细菌和色度去除效果明显,细菌的去除符合一级反应动力学方程,对COD和浊度去除有一定效果,但不显著。结果还发现,水体pH值随时间呈上升趋势。     

超声破解污泥上清液对A~2O工艺脱氮除磷和微生物群落结构的影响

为了提高传统污水处理工艺的脱氮除磷效率、实现污泥资源化,本实验通过超声破解污泥获取碳源,采用耗氧呼吸速率分析上清液作为碳源的可行性,并将上清液回用于生活污水,考察其对A2O工艺长期运行的脱氮除磷效果和微生物群落结构的影响。结果表明,上清液中可降解有机物达到76.2%,具有作为内碳源的潜能;上清液和生活污水按1∶15投入A2O反应器后,氮、磷的去除率分别从63.2%和53.4%提高到了82.1%和94.7%;上清液明显改变了微生物群落结构,使除磷菌Actinobacteia和反硝化聚磷菌Sphingobacterium富集。