与垃圾焚烧协同的污泥热干化工艺选择

针对生活垃圾焚烧厂掺烧污泥的应用实践,概述了3种污泥前处理热干化工艺——直接干化、间接干化和两段式干化,分别介绍了每种工艺的流程并结合污泥干化时的关键问题分析了每种工艺的优缺点,得出了间接干化为最适用于掺烧的污泥预处理工艺的结论。同时,还指出对于生活垃圾掺烧而言,高效率的低温污泥热干化将是未来的发展方向。     

回转式污泥干化过程的试验研究及特性曲线拟合

对回转式污泥干化过程进行试验研究,从污泥颗粒粒径、干燥介质温度和干污泥返混3个因素,探讨对污泥干化过程的影响.结果表明:当污泥粒径越小时,干化速率越快;污泥粒径相同时,干燥介质温度越高,污泥干化速率越大;当干污泥返混率大于30％时,污泥干化所需要的时间明显缩短.同时对干化过程特性进行曲线拟合,引入Growth/Sigm...     

薄层干化机污泥干化过程能耗及污染物特性研究

依托上海某建成的2×100 t/d薄层干化机污泥干化工程实例,分析了市政脱水污泥粒径分布规律,污泥粒径对干化过程的影响,干化过程中干污泥含水率与能耗的关系,以及废水、废气排放特性。结果表明:污泥干化至含水率约为30%,有利于干化系统的节能、稳定运行及干污泥的协同处置,恶臭气体的厂界浓度满足GB14554—1993恶臭污染物排放标准的规定,而干化过程产生的废水、废气需经过相应的处理后才能达标排放。     

印染污泥焚烧干化方法经济性分析

介绍了深度脱水和热力干化2种污泥干化方法,通过对这2种污泥干化方法的药剂配方、实验装置、干化效果、影响因素、能耗及经济性的对比研究,得出污泥深度脱水技术是适合我国污泥处理处置的新途径。     

污泥干化焚烧技术的应用

分析了目前市政污泥处置现状及处理方法,以温州某污泥干化焚烧项目为例,介绍了污泥干化焚烧技术在污泥处置中的应用。     

污泥间接热干化过程尾气排放特性及生成机理分析

通过对热干化前后污泥成分分析以及干化过程中尾气排放特性曲线测定,对污泥干化过程尾气的生成机理进行了分析。研究发现污泥经过干化之后,污泥的干基有机质和蛋白质含量均减小,污泥中的有机质是污泥干化过程中尾气生成的重要反应物。用基于傅立叶变换红外光谱的Gasmet DX-4000烟气分析仪对NH_3、CH_4、SO_23种主要气体污染物的排放进行实时测定,结果表明,NH_3是污泥间接热干化过程中产生的首要气体污染物,其排放与污泥中含有的蛋白质直接相关,CH_4和SO_2的排放与污泥中的蛋白质无关,是由污泥中含有的其他有机物反应产生。     

污泥干化特性影响因素的实验研究

对深圳市3座污水处理厂的旱季污泥进行了泥质分析,并采用桨叶式污泥干化机对热源温度和搅拌转速对污泥干化效果的影响进行了研究。结果表明:热源温度越高,干化速率越高;提高搅拌转速可以在一定程度上提高干化速率,但并不是转速越快,干化速率越高,过高的搅拌转速甚至会对干化过程带来不利影响。     

圆盘式蒸汽半干化污泥系统技术探讨

介绍圆盘式干化器及半干化污泥系统各辅助设备，详述圆盘式污泥半干化过程系统流程。以某工程为例，对半干化过程进行热量及物料平衡分析，并对污泥半干化过程运行成本进行测算。     

剩余污泥低温半干化过程的实验研究

将不同种类和比例的添加剂分别加入剩余污泥中,采用3种不同间接干燥方式对其进行低温半干化实验,考察了添加剂加入量、添加剂种类、加热方式对污泥半干化效果的影响,确定了污泥最佳低温半干化方式及条件。     

污泥干化二次污染物特性研究

污泥经干化后仍将产生冷凝水、不凝性气体等二次污染物。通过对常规市政污泥进行干化实验,并同步对干污泥性能指标、冷凝水水质指标、不凝性气体污染物指标进行观察和实验测定,然后对上述指标进行分析,从而得出结论,为污泥干化工程的设计和优化提供参考。     

威海市城市污水厂污泥处理方案建议

综述了国内常见的污泥最终处理方案,对其技术性、经济性和可行性进行了分析和比选,并针对威海城市污水处理厂污泥的特性,提出了污泥近期可以考虑“以综合利用为主,焚烧为辅,卫生填埋配套”,远期则可以考虑“以干化焚烧为主,卫生填埋为辅”的处理方式.     

生活垃圾渗沥液处理产生污泥的混烧研究

介绍了国内污泥的处理方式,阐述了生活垃圾渗沥液处理产生的污泥混烧的技术路线,并通过干燥污泥焚烧燃料费的计算表明了该技术是可行的.     

镁盐固化污泥及污泥焚烧灰渣作为原生污泥新型固化剂应用工艺研究

根据以废治废的原则,提出以镁盐固化污泥和污泥焚烧灰渣作为原生污泥固化剂.结果表明,当镁盐固化污泥与原生污泥混合搅拌的投加比例达16.7％时,经过7 d的养护,原生污泥含水率由80％降至22％左右:以污泥焚烧灰渣作为固化剂,也能够明显改善原生污泥的脱水性能,在投加比例为4.76％～16.7％的条件下,经过3 d和6 d的...     

污泥焚烧厂烟气处理工艺探讨

针时国内典型的污泥成分,通过计算污泥焚烧烟气中的污染物初始浓度,分析不同的烟气处理工艺,对适合我国污泥特点的污泥焚烧厂烟气处理工艺进行了探讨.     

深圳市污水处理厂污泥焚烧处理可行性研究

通过对深圳市污水处理厂污泥焚烧处理有关的重要泥质参数的分析,掌握了深圳污水污泥泥质的基础数据,探讨了适合深圳市实际情况的污水污泥焚烧处理的可行性.     

Short-Term Bioassay Responses to Sludge Products and Leachate

Recycling of sewage sludge is needed in a sustainable society. Quality aspects of sludge include hygiene (pathogens), nutrients (N and P), and toxicants (metals and organics). Metals are of particular concern because they are not degradable, but their hazards are related to their bioavailability and chemical speciation. In this article, the effect on sludge quality of two treatment methods, incineration and pelletization, has been determined for digested sludge from two treatment plants. The combined effect of nutrients and toxicants in sludge and sludge product was determined for spring wheat, Triticum aestivum, and the toxicity of the leachate water was determined for water fleas, Daphnia magna, and seeds of lettuce, Lactuca sativa. Toxicity Identification Evaluation was used to determine whether metals were possible toxicants. The results indicated that incineration decreased toxicity, whereas leachability of metals and the fertilizing effect was unaffected. Pelletization seemed to increase toxicity and leachability of metals and also decreased the fertilizing effect of the sludge. Thus, the results suggest that pelletization of digested sewage sludge increased the toxicity of the sludge and thus decreased the quality of the sludge, whereas incineration apparently reduced toxicity for the two sludges tested.     

Radioactivity in municipal sewage and sludge.

OBJECTIVE: To determine the environmental consequences of discharges of radioactivity from a large medical research facility into municipal sewage, specifically 131I activity in sewage sludge, and the radiation exposures to workers and the public when sludges are incinerated. METHODS: The authors measured radioactivity levels in the sludge at the Ann Arbor, Michigan, Waste Water Treatment Plant following radioiodine treatments of two patients at the University of Michigan hospital complex and performed a series of calculations to estimate potential radiation doses due to releases of 131I from incineration of sewage sludge. RESULTS: Approximately 1.1% of the radioactive 131I administered therapeutically to patients was measured in the primary sludge. Radiation doses from incineration of sludge were calculated to be 0.048 millirem (mrem) for a worker during a period in which the incinerator filtration system failed, a condition that could be considered to represent maximum exposure conditions, for two nine-hour days. Calculated results for a more typically exposed worker (with the filtration system in operation and a 22-week period of incineration) yielded a committed effective dose equivalent of 0.066 mrem. If a worker were exposed to both conditions during the period of incineration, the dose was calculated to be 0.11 mrem. For a member of the public, the committed effective dose equivalent was calculated as 0.003 mrem for a 22-week incineration period. Exposures to both workers and the public were a very small fraction of a typical annual dose (about 100 mrem excluding radon, or 300 mrem with radon) due to natural background radiation. Transport time to the treatment plant for radioiodine was found to be much longer than that of a normal sewage, possibly due to absorption of iodine by organic material in the sewer lines. The residence time of radioiodine in the sewer also appears to be longer than expected. CONCLUSION: 131I in land-applied sludge presents few health concerns because sufficient decay occurs before it can reach the public however, incineration, which is done in winter months, directly releases the 131I from sewage sludge to the atmosphere, and even though exposures to both workers and the public were found to be considerably lower than 1% of natural background, incineration of sludge in a pathway for public exposure. Although 131I was readily measurable in sewage sludge, only about 1% of the radioione administered to patients was found in the sludge. The fate of the remaining radioactivity has not been established; some may be in secondary and tertiary residuals, but it is quite likely that most passed through the plant and was discharged in dilute concentrations in plant emissions. The behavior of radioiodine and other radioactive materials released into municipal seweage systems, such as those from large medical facilities, is not yet well understood.     

污水厂污泥资源化技术研究进展

介绍了污泥在土地利用、焚烧及生产建材等资源化利用技术研究进展,并指出污泥资源化技术在我国的应用前景。