Experimental study on agitated drying characteristics of sewage sludge under the effects of different additive age

Drying experiments of dewatered sewage sludge (DSS) were conducted on a agitated paddle dryer, and the effects of additive agents, i.e., CaO, pulverized coal (PC), heavy oil (HO), and dried sludge ("DS" through back mixing) on the agitated drying characteristics of DSS were investigated. The results indicated that CaO can significantly increase the drying rate of DSS. The drying rate at CaO/DSS (mass ratio) = 1/100 was 135% higher than that of CaO/DSS = 0. Pulverized coal has no obvious effect on drying rate, but the increase of PC/DSS can promote breaking up of sludge lump. Heavy oil was found to be slightly effective in improving the drying rate of DSS in the examined experimental range of HO/DSS = 0-1/20. It is also found thatHOcan reduce the torque of the dryer shaft, due to its lubrication effect. Back mixing of DS was found to be effective in alleviating the unfavorable effect of the lumpy phase by improving the mixing effect of the paddle dryer. There was a marked increase of drying rate with an increase of the DS/DSS in the experimental range of DS/DSS = 0-1/3.     

Management of process performance at low water temperatures in respect of filamentous organisms

The management of sludge-settling properties in Nordic conditions is of importance during the low temperature (spring) season because of the peak settler load. A survey was made in 10 Finnish waste water treatment plants(WWTP‘ s) and the total extended filament length and DSVI in haft of the plants exceeded the limits, which indicates sludge bulking( 15 km/g SS and 150 ml/g respectively). The dominant organism was Microthrix parvicella, the abundance of which was 59.22% of total extended filament length on average.Chemicals were tested to control the filaments, and it was found that special attention has to be paid to maintaining the nitrification at low temperature. A dosage of(H2O2-besed) oxidants controlled the growth of Microthrix parvicella effectively and rapidly, whereas with the use of aluminium hydroxidechloride a 2 to 5-week period was needed to decrease the filament length.     

上海城市污水厂污泥处理与利用系统分析

上海市城市污水处理规划的实施，将在2020年前使该市的城市污水厂污泥产生量从现状的85tDS/d增长至1300－1500tDS/d，将形成可观的污泥消纳压力。预期了该市的污水污泥产生状况，以现有污水污泥处置与利用技术为基础，测算了可行的污泥处置与利用方向及相应的容量，以及满足容量利用的前处理要求。以此为基础，推荐了适宜的容量利用方案，并建议以生物稳定化干化处理为污泥处置与利用前的改性处理步骤，且可在适当的条件下增加厌氧消化环节，提高处理体系的水平与容量宽余度。此污泥处理与利用体系可达到污泥消纳运行的柔性化和可靠性，兼具环境安全性与经济合理性。     

好氧颗粒污泥对酸性红B的生物吸附模型研究

考察了灭活好氧颗粒污泥吸附酸性红B的吸附等温线、吸附动力学和热力学.结果表明,Langmuir和Redlich-Peterson比Freudlich吸附等温线更符合试验数据,20 ℃时Langmuir最大单分子层吸附量为123.46 mg/g.吸附动力学符合准2级动力学模型.灭活AGS内部扩散过程用Webber-Morris模型拟合,结果表明颗粒内部扩散过程是限速步骤,但边界层扩散和动力学阻力亦不能忽略.热力学分析表明,吸附过程是吸热且自发的过程.     

活性污泥法处理焦化污水监测值的统计特性

用活性污泥法处理焦化污水,将一年内监测的曝气池山水和入水中酚、氰、氨氮、COD等指标建立数据库,并进行时间序列、正态分布性、自相关和线性回归分析.统计分析结果表明,多数指标呈正态分布而周期性特征不明显;经多元线性回归分析,出水COD与入水COD、出水酚之间的关系较为密切.     

农村生活污水深度处理适用技术

农村污水治理是改善农村人居环境的重要内容之一,介绍了3种适用于农村水质敏感地区的污水处理技术:间歇曝气活性污泥法、生态处理技术、膜生物法,并对3种污水处理技术的优缺点进行了比较分析。     

腐殖酸对生物炭去除水中Cr(Ⅵ)的影响机制研究

以污泥生物炭作吸附剂处理水中Cr(Ⅵ),研究了共存腐殖酸对生物炭吸附性能影响.结果表明,腐殖酸能显著促进生物炭对Cr(Ⅵ)的吸附,大幅提高吸附量以及缩短吸附平衡时间,生物炭吸附过程符合准二级动力学模型.在溶液初始pH4.0,生物炭浓度20 g·L-1,Cr(Ⅵ)初始浓度在50～800 mg·L-1范围下,Langmuir模型比Freundlich模型更好地描述等温吸附行为.加入腐殖酸(20 mg·L-1)后拟合得到的理论饱和吸附量达10.10 mg·g-1,较未加入腐殖酸的吸附量5.56 mg·g-1提高近1倍.在pH 2.0～8.0范围内,吸附量随溶液初始pH值升高而减小.腐殖酸浓度上升,生物炭吸附能力进一步提高.红外光谱显示,生物炭表面的羟基、羧基、酯基、芳香环上C—H和环状结构上的CC等化学活性官能团与Cr(Ⅵ)的吸附有关.结合XPS分析结果,推断腐殖酸共存促进生物炭吸附的机制是:腐殖酸提高了Cr(Ⅵ)在生物炭表面聚集浓度,有利于生物炭对Cr(Ⅵ)的直接吸附和还原,而腐殖酸本身具有的吸附能力增加了对溶液中Cr(Ⅵ)和Cr(Ⅲ)的去除.     

2种多级厌氧系统处理高浓度焦化废水

利用多级厌氧无污泥返混与多级厌氧有污泥返混系统处理高浓度焦化污水后 ,证明多级厌氧无污泥返混系统 (各步之间没有生物数量的混合 )的性能优于多级厌氧有污泥返混系统 (各步之间有生物数量混合 )。多级厌氧无污泥返混比多级厌氧有污泥返混系统更能抵抗冲击荷载 (pH值高、COD和NH3 N浓度高 )、产生更多的沼气     

The formation of aerobic granular sludge for the treatment of real landfill leachate using a granular sequencing batch reactor at a constant volume

Leachate generated in a landfill may not be treated by conventional biological treatment due to its nature and complexity. The process of forming aerobic granules in batch sequencing reactors having features such as; reducing the settling process time and saving energy consumption and high decomposition rate have been noticed by researchers. In the present study, the structure of sequencing batch reactors (SBRs) was evaluated for the formation of granules, which were subsequently utilized for the treatment of landfill leachate. The experiment was initiated by using the GSBR, containing 1200 ml with different apparatuses, to develop granular sludge, and synthetic wastewater was added to reinforcement. The selected parameters for the operational hydraulic retention time (HRT) of the wastewater (6-h cycles) included feeding, idle, aeration, settling, and discharge. Furthermore, the controlled conditions were the dissolved oxygen (DO) range of 2–2.2 mg/L, temperature range of 20–23℃, and pH of 7.5–8.3. The chemical oxygen demand (COD), mixed liquor suspended solids (MLSS), and sludge volume index (SVI) daily were measured at the influent and effluent of GSBR reactor. The main properties of aerobic granular sludge were identified during the research procedures, and the remarkable settling and potent, high-density microbial structure of the granules were confirmed. The mean size of the formulated granules was estimated at 7.46 ± 1.8 mm, and the volume of the biomass also increased from approximately 1607 to 4137 mg/L through the granulation process. Moreover, 98% of the influent chemical oxygen demand (COD) could be removed by the formulated granular sludge, and the final-stage organic loading rate was estimated at 5.65 COD/m³/day. According to the results, GSBRs could be employed for the formulation of aerobic granular sludge for the treatment of landfill leachate.     

热-碱处理污泥与木耳菌糠共发酵产酸性能的研究

为克服单一剩余活性污泥(WAS)发酵产酸效率低的问题和资源化利用废弃木耳菌糠(SMS),本文对热-碱预处理污泥(PWS)和菌糠进行共发酵,研究预处理和菌糠添加对共发酵体系的产酸性能影响.试验基于原料的总固体含量(TS)共设置6个处理,分别为污泥(WAS∶SMS=1∶0)、预处理污泥(PWS∶SMS=1∶0)、菌糠(PW...