The influence of sewage sludge properties on sludge-borne metal availability

With the advent of more stringent controls on wastewater treatment, sewage sludge production in Europe and many parts of the world is increasing. With this increase comes the problem of sludge disposal, and recycling to land arguably offers an economically and environmentally sustainable option. However, a major limitation of sewage sludge reuse is the potential release of heavy metals from the sludge and heavy metal accumulation to toxic levels in topsoils. The properties of the sludge play a crucial role in determining the initial release and subsequent availability of heavy metals in amended soils. Bioavailable forms of heavy metals in recently amended soils are most likely to be those that are bioavailable in the sewage sludge. In this paper, published research on the importance of sewage sludge characteristics on metal release and bioavailability will be reviewed and contrasted with original research. A selection of sludges from around Australia has been collected for this purpose. Through the use of incubation studies, isotope dilution techniques, ion-selective electrode measurements and ¹³C-NMR spectroscopy, the importance of a range of sludge properties on heavy metal behaviour in sludges and sludge-amended soils is addressed.     

厌氧升流式污泥层反应器内污泥颗粒化对固液分离效果的影响

厌氧升流式污泥层反应器在较高的COD容积负荷和水力负荷下稳定运行的关键是要有良好的固液分离,而固液分离的必要条件是污泥的沉降速度大于混合液在三相分离器的沉降区的最小断面上的向上流速。通过小型装置的试验表明,污泥的沉降速度与污泥的性状和浓度有关,使反应器内的污泥颗粒化能改善污泥沉降性、提高固液分离效果,使反应器能在相当高的COD容积负荷(20—30kgCOD/m~3·d)和水力负荷(0.8m~3/m~2·h)下稳定运行。本文叙述了厌氧升流式污泥层反应器内的污泥颗粒化过程,并简要地讨论了培养颗粒污泥的基本条件。     

活性污泥生长的控制

在污水处理过程中，针对不同的运行环境，我们选择适当的运行工艺和参数。通过控制菌胶团细菌和丝状菌平衡生长，或者是使固着型原生动物占优势，来获得良好的活性污泥，保证出水达标排放。     

转炉污泥干法脱硫新技术应用

采用转炉污泥取代铸铁屑配制焦炉煤气脱硫剂,转炉污泥与稻壳体积配比为1∶2,水分30%～40%,pH值8～10。经过生产实践证明,脱硫效率达到996%～998%。既降低了煤气生产成本,减轻工人劳动强度,又提高了民用煤气质量,具有可观的环境效益与经济效益。     

二沉池漂泥原因及控制措施

二级污水处理厂二沉池漂泥有反硝化漂泥、活性污泥老化漂泥、生物泡沫导致的漂泥。最终的解决办法是：分析漂泥原因、对症下药、改善工艺运行状况、采取有效的控制措施.     

Possible Utilization of Silica Gel Sludge for the Removal of Phenol from Aqueous Solutions: Laboratory Studies

This paper discusses the adsorption capacity of silica gel sludge for phenol removal from aqueous solution. Kinetic experiments showed that phenol adsorption was completed after 2 h. Adsorption isotherms were measured for phenol from aqueous solution onto silica gel sludge under various pHs and temperatures. Results showed that the adsorption capacities for phenol was increased as pH decreased from 6.5 to 2. Temperature also was found to affect the adsorption isotherm. As temperature increases from 30 to 50°C, the adsorption capacity increases. The adsorption equilibrium of phenol on silica gel sludge was described by the linear Freundlich and Langmuir models. Furthermore, results showed that the isotherm parameters fit both linearized Langmuir and Freundlich adsorption isotherms. The Freundlich and Langmuir parameters at optimum pH was found as K _f=2.89, 1/n=0.23 and K _d=22.0, q _m=7.98, respectively. Whereas, for those at optimum temperature it was observed as K _f=2.87, 1/n=0.16 and K _d=20.93, q _m=7.91, respectively.     

炼油厂"三泥"离心脱水处理研究

通过对目前炼油厂“三泥”性状的调查，利用已有污泥处理设施进行了炼油厂“三泥”离心分离的现场试验，并分析了影响“三泥”离心分离处理工艺的主要因素，发现了离心机转速和絮凝剂投加量对“三泥”离心分离的有关规律和最佳操作条件，在此基础上，提出了适合炼油厂“三泥”处理系统的优化方案。     

活性污泥吸附重金属Cr6+的研究

以活性污泥为材料，采用不同时间、温度、pH进行吸附重金属Cr^6 的研究。实验结果表明，当吸附时间为15min，吸附温度为28℃，吸附pH=7时具有较好吸附效果。在此条件下，当重金属Cr^6 浓度为50mg/L，其吸附率可达97．2％。     

不同电压下给水污泥真空电渗脱水效果分析

采用真空电渗对给水污泥进行脱水,结果表明电压从30 V提高到60和100 V,给水污泥含水率从90%分别降低到63.2%、62.8%和58.7%。详细考察电压对电流最大值、最高温度的影响,其电流最大值从0.63 A分别提高到1.32和1.88 A;最高温度从38.4 ℃分别提高到43.6和62.2 ℃。水分分布和扫描电镜分析表明：脱水后,其自由水被全部去除,孔隙水含量从19.83下降到0.41 kg·（kg 干泥）-1,表面结合水含量从5.35下降到0.18 kg·（kg 干泥）-1。     

城市污水厂污泥内循环自热高温微好氧消化的处理

利用一种新型的内循环自热式污泥高温微好氧消化装置对城市污泥进行消化处理。通过在反应器中增加内筒的方法,使得内筒中污泥通过搅拌器的提升作用在内外筒之间循环以提高消化速率。结果表明,增加内筒之后,消化系统的污泥VS去除率在第16天达到了41.52%,而未添加内筒的反应器污泥到第20天时仍未到达稳定化水平。因此,加了内筒的单段式ATAD消化反应器与不加内筒的单段式ATAD消化反应器相比可以使得污泥更快地达到稳定状态。另外,与没有内筒相比,增加内筒后反应器顶部和底部的ORP和pH值均维持较高水平,消除了曝气死角。增加内筒后,顶部和底部污泥上清液中SCOD、VFA、TN、NH4+-N和TP浓度基本保持一致,而没有内筒则相差较大,表明增加内筒后,反应器内污泥混合更加均匀。