Existing Situation on Disposal of Sludge from Wastewater Treatment Plant in Three-Gorges Reservoir Area

At present 18 wastewater treatment plants operateing in the Small towns of Three Gorge Areas of Chongqing Municipality, producing 132.95 tons surplus sludge everyday. As regards to the disposition of such numerous surplus sludge, the major disposition technique in these wastewater water treatment plants, i. e. , thickening and mechanical dewatering technique followed by feeding into the municipal solid waste landfill, seems to have a rather bad effect on the normal operation of the municipal solid waste landfill, due to the unstabilized sludge resulted from this technique of the sludge disposition and high moisture in the sludge, which is higher than 80%. This paper has paid some attention to this phenomenon. With respect to the small towns having the the municipal solid waste landfill, the techniques of mechanical dewatering, calcareousness stabilized etc. before feeding into the municipal solid waste landfill, seem to be feasible, while the composting and comprehensive utilization of sludge is available in the small towns which have no municipal solid waste landfills.     

陆地棉果胶甲酯酶GhPME6的克隆及功能分析

结合陆地棉SSH-cDNA文库的测序结果,与棉花EST数据库进行序列比对和分析,获得1条在棉纤维次生壁加厚期特异表达的EST序列,该序列编码果胶甲酯酶(PME)。利用RACE技术获得其全长cDNA序列,命名为GhPME6。基因结构分析表明,GhPME6包含1个长度为1560 bp的开放阅读框、2个外显子和1个内含子,编码含有519个氨基酸的蛋白。其氨基酸序列具有PMEI和Pectinesterase两个保守结构域。通过对不同棉属基因组中的PME6基因进行比对分析,发现PME6在进化过程中具有高度保守性。qRT-PCR分析显示,GhPME6在纤维发育次生壁加厚期大量表达,推测该基因可能对棉纤维比强度有重要影响。构建GhPME6基因的大肠杆菌表达体系,获得与预期大小一致的目的蛋白,为深入研究GhPME6对棉纤维比强度的影响奠定了基础。     

棉纤维加厚发育期间纤维素生物合成研究进展

棉纤维加厚发育期纤维素的沉积影响纤维强度的形成,本文综述了棉纤维加厚发育期间纤维素生物合成过程中的物质变化、酶促作用,以及影响棉纤维素生物合成的因素。利用生理或分子生物学手段,研究纤维素生物合成的生理基础及其酶活性调节水平的基因表达特征,可以揭示棉纤维强度的形成机制,为进一步探索改善纤维强度的生理调控途径和运用分子手段培育高强纤维品种提供理论依据。     

Selection of Polymeric Flocculant for Adjusting the Sludge Quality of Municipal Wastewater Treatment Plants

The thickened surplus sludge from municipal wastewater treatment plants is generally mechanically dewatered after regulated with flocculants and the type and dosage of flocculants will influence the dewatering effect directly.And the cost of flocculants is the main part of operating cost of sewage sludge treatment.With the processing practice on yields,thickening and dewatering pattern of Zhenjiang Wastewater Treatment Plant,the analysis and selection of flocculants are carried out with respect to the type and dosage of flocculants for sewage sludge regulation.the principles for flocculants selection and simple calculation method for chemicals cost for sludge treatment are proposed.It is suggested that the dosage of flocculants for sludge regulation should be adjusted in different seasons in real operation of the municipal wastewater treatment plants.     

增稠剂对特一粉冷冻面团拉伸特性的影响

以特一粉冷冻面团为研究对象,通过质构仪,研究添加黄原胶、卡拉胶、瓜尔豆胶、聚丙烯酸钠对冷冻面团拉伸特性的影响,通过单因素试验进行响应面分析。结果表明,当添加黄原胶为0.33%,瓜尔豆胶为0.90%,卡拉胶为0.61%,聚丙烯酸钠为0.05%时,得出最大拉伸面积,对冷冻特一粉面团品质有很好的改良作用。     

棉纤维加厚发育生理特性的基因型差异及对纤维比强度的影响

选择3类棉纤维比强度差异明显的品种,于2004—2005年在江苏南京（长江流域下游棉区）研究棉纤维加厚发育过程中主要生理特性的基因型差异及对纤维比强度的影响,为探索改善棉纤维比强度的生理调控途径提供理论依据。结果表明,高纤维比强度基因型（科棉1号）棉纤维中可溶性糖转化多,进入纤维次生壁加厚发育期的β-1,3-葡聚糖含量峰值高,纤维素合成关键酶（蔗糖合成酶和β-1,3-葡聚糖酶）活性增强快、峰值高,纤维素累积速率平缓且快速累积期长;而较低纤维比强度基因型（苏棉15和德夏棉1号）的棉纤维加厚发育生理特征与此相反;中等棉纤维比强度基因型（美棉33B）则介于上述两者之间。与纤维素生物合成相关的物质和关键酶活性变化的基因型差异是造成纤维素累积速率及纤维比强度差异的主要生理原因之一。此外,β-1,3-葡聚糖含量的剧增可作为棉纤维进入次生壁加厚发育阶段的一个重要特征。     

棉花季节桃加厚发育生理特性的差异及与纤维比强度的关系

选用3类棉纤维比强度差异明显的4个棉花品种, 研究棉花伏前桃、伏桃、早秋桃和晚秋桃纤维加厚发育过程中主要生理特征的差异及与纤维比强度的关系。结果表明, 棉花季节桃纤维加厚发育过程中物质转化特征和相关酶活性存在较大差异, 最终导致纤维比强度差异的形成, 且季节桃间的差异在各类品种内表现一致。伏前桃和伏桃纤维加厚发育处于较为适宜的温度条件(铃龄10~50 d日均温26.0~28.5℃)和棉株生理年龄(3~9果枝)下, 纤维素合成相关酶活性越高, 相关物质转化越多, 纤维素快增持续期长, 纤维素累积速率平缓, 越利于高强纤维的形成。早秋桃纤维发育后期温度条件较伏前桃差且棉株开始衰老, 但其纤维合成相关物质转化率高, 纤维素累积特征优于伏前桃, 最终纤维强度高于伏前桃; 随着铃龄10~50 d日均温降至20℃以下和棉株进一步的衰老(16果枝以上), 晚秋桃纤维素快速累积期延长, 相关物质转化率降低, 纤维累积速率过慢, 纤维细胞发育迟缓, 造成最终纤维比强度较低。     

Microbial Community Structure and Ecological Variation in TISTD Reactor

Based on the sewage treatment device of Two-phase Integrated Sludge Thickening and Digestion reactor (TISTD), microbial community structure in stable operation and its ecological variation when load changes are investigated. During a stable operation with 30% sludge dosage rate, 20 dominant bacterial strains are individually isolated from acid-phase and methane-phase of the reactor. Sequence analysis of 16S rDNA reveals that six of the achieved strains belong to Bacillus, Methanospirillum and Methanococcus respectively. Ten sludge samples are collected separately in 5 periods when the reactor operates with 10%, 20% and 30% sludge dosage rate and in the state of started-up and disordered, and followed by DNA extraction, purification, 16S rDNA PCR amplification and temperature gradient gel electrophoresis (TGGE). The good quality of DNA extraction and amplification demonstrates that there is an abundant biomass in the sludge under mid-temperature condition. The results show that TISTD reactor has a high biodiversity in microbial communities and is complex and stable in ecosystem structure, which effectively supports the good digestion in sludge thickening.     

污泥膨胀的原因及其控制方法

污泥膨胀不仅影响出水水质,增大污泥的处理费用,而且极易引起大量污泥流失,严重时可导致整个处理工艺失败。污泥膨胀分为丝状菌性污泥膨胀和非丝状菌性污泥膨胀,主要影响因素有污水水质、溶解氧、污泥负荷、冲击负荷以及运行方式和处理工艺等。通过临时控制措施、工艺设计控制措施、工艺运行控制措施可有效解决污泥膨胀问题。尽管当前有一些理论解释污泥膨胀问题,如表面积/容积比(A/V)假说,动力学理论,饥饿假说理论、NO假设,但缺乏充分的实验证明模型适用与否。需进一步完善污泥膨胀理论,为控制污泥膨胀提供严谨的理论依据。     

不同配比污泥基质对2种草本植物生长的影响

以北京小红门污泥转运站的生活污泥为研究对象,探讨不同配比污泥基质处理对高羊茅和黑麦草生长的影响,为北京市合理利用城市生活污泥提供科学理论依据。采用土壤农化常规分析法对污泥基质进行分析,通过对比试验对2种草本植物的生长和生理指标进行比较。研究表明,污泥的施用明显改变了土壤的生化指标,进而影响了植物的生长发育。对于生污泥来说,随着配比比例的增加,高羊茅和黑麦草各项生长指标均呈现先增加后减少的变化规律;而对于污泥混合类型来说,50%生污泥和50%脱水泥饼更有利于草种的发芽和生长;当污泥配比比例超过60%时,会抑制植物的发芽和生长。另外,对于施用污泥的植物来说,其生理指标叶绿素含量明显增高,并且丙二醛含量也有显著变化。研究结果将为污泥矿山修复利用技术提供理论指导作用。     

Sludge Treatment and Energy Consumption of Urban Water Plant

This paper introduces the composition and the treatment process of sludge and energy consumption of dewaterizers in urban water treatment plant, the new development of sludge treatment techniques and the comprehensive uses of the sludge are evaluated. The calculation formulas for power consumption and economical benefit of wastewater recovery are presented with examples, offering a basis for economical evaluation to energy consumption of the technology of wastewater recovery in water works .     

Influence of Distance from Blasting Center on Frequency Bands Energy Distribution of Blasting Vibration Signals

研究了以金柑和白砂糖为主要原料制作金柑酱的加工工艺.比较了几种抗氧化剂和增稠剂对金柑酱产品品质的影响,确定添加0.02%鲜多宝可对金柑酱有良好的护色效果;CMC作为金柑酱增稠剂效果良好,添加量为0.1%.     

Membrane Bioreactor for Treatment of Wastewater

Membrane Bioreactor (MBR) is a new technology in wastewater treatment, using membrane to enhance biological-chemical reaction. It has many advantages such as high efficiency and low sludge production rate. By analyzing the factor influencing MBR, a new submerged hybrid dynamic membrane bioreactor(HDMBR) is suggested and the characteristics of the new HDMBR from different viewpoints are expounded. It shows that this technology is a process of high efficiency and low consumption.     

城镇污泥生物沥浸减量试验研究

通过生物沥浸技术实现对城镇污水处理厂污泥减量并最终达到资源化利用的目的,具有非常重要的实际意义。利用可移动集装箱式试验机,采用续批式运行模式对天津本地两处污水处理厂污泥进行生物沥浸减量实验。结果表明,环境温度为15~25℃、曝气量为1.2L/min、反应时间72h,初始批次将260L接种物和0.73kg营养剂投入400L原泥中,按回流比40%进行3批次沥浸实验。当反应结束后,2种污泥3批次的终点pH从沥浸前的5左右可降至3以下。2种污泥的镉、铜、锌、镍平均溶出率都达到80%以上,其中锌、镉的溶出率分别达到了94.26%、86.67%以上,平均溶出效果从高到底依次为锌＞镉＞铜＞镍。汞、铅、砷的平均溶出率最低,分别为21.42%、20.4%、23.52%。2种污泥经生物沥浸固液分离后,泥饼含水率均降至53%以下。向压滤液分别投加4kg/t、2kg/t石灰后,污泥1、2的上部澄清液中氨氮、COD及污泥1的SS都超过了污染物一级排放标准。与原泥相比,粪大肠菌群杀灭率达到99.99%,沥浸过程造成总养分分别损失24.89%、9.31%,有机质也有所损失,泥饼盐分含量超过2.00%。因此,生物沥浸具有很好的应用效果及应用前景,为进一步在本地工程化应用提供了相关依据。     

Sludge Deposition Analysis and Flow Pattern Test on OxidationDitch Integrated A/A/O Technique

To study the velocity distribution rule, the sludge deposition and the energy-optimized distribution of the oxidation ditch, the experiment was processed in a WWTP with A/A/O Oxidation Ditch technology. The study individually focused on the velocity distribution of curved sections in out-ditch by testing three operation conditions of the Oxidation Ditch. The result shows: firstly, the velocity of the first ditch is too large; easily lead to waste of energy, intermittent on/off submerged flow drivers can optimize the energy distribution of the system. Secondly, in the second ditch, the flow pattern in crook ditches were very complex, there existed high velocity outside and low inside. For such situation, it is easy to cause sludge deposit in the inside of the ditch. Finally, in order to improve the problem of sludge deposition, the measures were put forward as follows: installing off-center training in curved sections of the second ditch, adjusting the position of submerged flow driver.     

壳聚糖与硅藻土调理市政污泥

以污泥比阻为评价指标,综合考虑脱水率、泥饼含水率及过滤时间因素,研究使用壳聚糖与硅藻土对污泥单独调理的最佳条件及联合调理改善污泥脱水性能的效果,并与聚丙烯酰胺调理污泥的效果进行了对比。结果表明,先投加0.5 g/g硅藻土调理污泥,再投加5 mg/g壳聚糖以30 r/min搅拌反应150 s,污泥比阻下降了95.43%,脱水率上升至91.02%,泥饼含水率降至83.13%,过滤时间降至29.5 s。壳聚糖与硅藻土联合调理的效果明显优于壳聚糖或硅藻土单独调理的效果,且其联合调理改善污泥脱水综合性能的效果优于聚丙烯酰胺调理污泥的效果。     

Carbon Emission and Low carbon Strategies of Sewage Sludge Treatment

The carbon emission during sewage sludge treatment is an important source of greenhouse gas. For the carbon reduction, the emissions from common treatment technologies are calculated with the mass balance model, then their low carbon degrees are evaluated, and finally the low carbon treatment strategies are put forward for different requirements. The results show that the technologies, such as digestion for methane recovery, incineration or co incineration for power production after drying with industrial waste heat, are the ones with the lowest carbon emission. Their low carbon degrees are 89.6%, 80.3% and 76.6% respectively. In the area where the above technologies cannot be applied, aerobic composting or landfill with aerobic stabilization pretreatment are the effective methods to reduce carbon emission. The low carbon treatment strategy, a new part of sludge treatment strategies, should be applied combining the local economy, technology and social conditions, so that it can meet the different requirements from sanitation to carbon emission reduction.     

污泥在花生上施用效果初报

通过田间试验初步探讨了污泥对花生产质量、土壤肥力以及花生与土壤重金属元素含量的影响。结果表明,每公顷施污泥7500~30000kg比不施花生产量增加6.3%~15.8%,且随着污泥用量的增加花生产量增加。污泥对改善花生品质,保持和提高土壤肥力具有作用。施用污泥处理花生和土壤重金属元素含量与不施污泥的没有明显差异,说明施用污泥不会产生重金属元素对作物和土壤的污染。     

施用污泥对土壤中重金属含量的影响

随着城市污水处理厂数量的迅速增加,污泥的处置及其环境影响受到越来越多的关注。污泥土地利用因具有处理费用低廉及高效性的特点,已成为重要的污泥处理方式。然而污泥中的重金属元素是限制其大规模农田利用的重要因素。施污土壤中重金属的形态研究可以用来评价土壤中重金属的生物有效性以及它们在土壤中的移动性。用修正BCR三步连续提取法进行分步提取研究了施污后的水稻田土壤中Cu、Pb、Cd、Zn的形态分布状况。与对照相比,在直接施用污泥的水稻田土壤中Cu、Pb、Cd、Zn的含量显著增加。但即使是在施污60t hm-2的土壤中,Cu、Pb、Zn的含量亦远低于我国土壤环境质量标准。在施污的水稻田土壤中4种重金属元素的形态分布规律为：残渣态＞可氧化态＞可还原态＞可交换态和弱酸溶解态。这些重金属元素在水稻田土壤中相对稳定性顺序为Zn＞Cu＞Cd=Pb。