堆肥化处理生活垃圾方法的探讨

分析了生活垃圾堆肥化的原理、影响因素以及现阶段发展水平,指明了堆肥化难以普及的主要原因是堆肥产品售出率低,针对堆肥化存在的问题提出了措施和建议,主要措施为提高堆肥产品的质量、完善堆肥前的预处理工作.     

城市污泥堆肥处理及其产业化发展中的几个关键问题

污泥堆肥处理后其有机质和N、P等营养元素可被农作物利用,促进作物增产,被认为是适合中国国情的污泥处理与处置方式.但受处理技术水平、人们的认知和可接受程度的限制以及国家政策法规、产品出路等问题的困扰,城市污泥堆肥处理及其产业化过程仍面临诸多不利因素.为从根本上解决城市污泥的处理与处置难题,城市污泥堆肥处理及其产业化过程中存在的问题必须予以解决,以加快其产业化进程.     

城市社区堆肥:美国实践案例研究及其对中国的启示

社区堆肥是城市垃圾减量与资源化的有效途径,亦是城市与社区可持续发展的重要基石。近年来,分散式社区堆肥实践在国外方兴未艾,其中的理念、模式与方法亟待总结。文章探究了美国社区堆肥的目标、特点和类型,进一步选取其典型案例,分析各案例社区堆肥项目的实践模式,并总结美国社区堆肥实践的要点。最后,阐述对中国的启示,以期为我国社区生活垃圾治理提供政策参考。     

堆肥过程中臭气的产生和释放过程研究进展

堆肥过程中产生的臭气容易导致恶臭污染问题.总结了堆肥过程中主要臭气物质的产生机理、物理化学性质、影响因素及调控措施.堆肥过程中产生的臭气物质主要包括NH<,3>、H<,2>S和部分挥发性有机物;H<,2>S是堆肥过程产生的恶臭潜力最高的臭气;NH<,3>的最大释放浓度可达6 000 mg/m<'3>.堆肥原料的C/N值、调理剂种类、通风条件是影响氨气挥发的重要因素.指出过程控制是解决臭气问题的根本措施.     

污泥堆肥化对重金属生物可利用性的影响

通过重金属形态分析及在模拟雨水、酸雨淋溶条件下重金属迁移实验和理论分析，研究了堆肥化处理对污泥中重金属生物可利用性的影响。结果表明：堆肥化处理使重金属的不稳定形态含量降低，原污泥在酸雨淋溶下重金属已经迁移到约16厘米深的土柱中，而经过处理后的污泥淋出液中的重金属含量很低，仅有少量污泥中含量较高的元素向土柱深层迁移。迁移量及深度明显低于未处理的原污泥。实验及理论分析均证明了堆肥化处理可以降低污泥中重金属在土壤中的迁移性，使重金属的生物可利用性降低。     

Quantitative effects of composting state variables on C/N ratio through GA-aided multivariate analysis

It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reactors were used to demonstrate the applicability of GASCA. Within the GASCA framework, GA searched optimal sets of both specified state variables and SCA's internal parameters; SCA established statistical nonlinear relationships between state variables and the C/N ratio; to avoid unnecessary and time-consuming calculation, a proxy table was introduced to save around 70% computational efforts. The obtained GASCA cluster trees had smaller sizes and higher prediction accuracy than the conventional SCA trees. Based on the optimal GASCA tree, the effects of the GA-selected state variables on the C/N ratio were ranged in a descending order as: NH₄⁺-N concentration > Moisture content > Ash Content > Mean Temperature > Mesophilic bacteria biomass. Such a rank implied that the variation of ammonium nitrogen concentration, the associated temperature and the moisture conditions, the total loss of both organic matters and available mineral constituents, and the mesophilic bacteria activity, were critical factors affecting the C/N ratio during the investigated food waste composting. This first application of GASCA to composting modelling indicated that more direct search algorithms could be coupled with SCA or other multivariate analysis methods to analyze complicated relationships during composting and many other environmental processes.     

城市污泥堆肥添加猪粪的功效研究

了解和调控高温堆肥过程中堆体内氧气浓度的变化,对于进一步优化堆肥工艺具有重要的意义.为此,利用自主研发的堆肥实时、在线自动监测系统,考察了城市污泥、猪粪以及城市污泥和猪粪混合堆肥过程中氧气浓度的变化.结果表明,添加猪粪可有效改善城市污泥堆肥的通气性;夏季堆肥的通气性好于冬季;降低堆体高度可以适当减少CTB调理剂的用量,并改善了堆体的通气性.     

堆肥过程中挥发性有机物的产生与释放

总结了堆肥过程中挥发性有机物(VOCs)的产生及其影响因素.堆肥产生的VOCs中,氮化物、硫化物及挥发性脂肪酸属于臭味物质,但大部分VOCs不产生臭味,其中甲胺、二甲胺、甲硫醇、乙硫醇、2-甲基呋喃和甲醛应作为堆肥厂职业健康安全评价时的参考指标.温度、通气状况是影响堆肥过程中VOCs释放的重要因素,温度升高可促使VOCs产生,适当通风可减少VOCs释放.     

济南市污水处理二厂剩余污泥好氧堆肥实践总结

光大水务济南市污水处理二厂将剩余污泥与稻壳、泥炭、粉煤灰等调理剂在优化配比为39∶11∶26∶24的条件下进行好氧堆肥。经30～35 d堆肥,病原菌得到有效杀灭,有机质腐殖化稳定,各类污染物含量均低于农用污泥中污染物控制标准,符合农用要求。该工程可产有机肥为1.2×104t/a,产品供不应求。实践表明,剩余污泥好氧堆肥具有良好的环境效益、社会效益和经济效益。     

生物可降解度判定生活垃圾堆肥处理的稳定性

准确判定城市生活垃圾（MSW）堆肥化处理的生物降解稳定性具有重要的环境、社会和经济意义，然而现有判定指标受垃圾组成不均匀性的影响，表现出一定的波动性。针对堆肥过程中微生物降解的主要对象——生物可降解物质进行研究，测定了接种1％高温菌、小风量连续通风静态好氧堆肥试验过程中生物可降解物质和有机质含量的变化。结果表明，堆肥过程中生物可降解度（BDM）受垃圾组分的影响较小，可较好地反映垃圾生物降解的规律，优于其他从有机成分变化角度判定MSW生物降解稳定性的指标。从动力学的角度，运用Matlab软件分段拟合出了整个堆肥过程中BDM变化曲线的表达式，验证了两段拟舍的可行性。     

污泥堆肥温度对微生物降解有机质的影响

污泥自然通风静态堆肥试验研究表明,堆肥过程中温度的变化引起微生物数量和种群的交替变化,从而影响对有机质的分解。而污泥堆肥过程有机质的降解主要是在中温阶段完成的,其中中,高温菌群起重要的作用。     

郑州市污泥堆肥处理工程的设计

郑州市污泥堆肥处理工程处理规模为600 t/d,采用好氧堆肥工艺处置三个污水处理厂的剩余污泥.介绍了工艺流程及发酵槽、混料仓、除臭系统等各处理单元的设计参数,可为相关工程提供参考.     

堆肥处理对排水污泥中重金属的钝化作用

讨论了城市排水污泥中重金属的含量和形态分布特征，分析了堆肥处理对污泥中重金属结合形态转化的影响。根据不同学者的研究结果，提出堆肥处理可降低污泥中Zn、Cu、Pb、Mn等重金属的活性，并指出堆肥处理是降低污泥在土地利用中重金属污染风险的途径。     

Critical components of odors in evaluating the performance of food waste composting plants

The current Taiwan government policy toward food waste management encourages composting for resource recovery. This study used olfactometry, gas chromatography-mass spectrometry (GC-MS) and gas detector tubes to evaluate the ambient air at three of the largest food waste composting plants in Taiwan. Ambient air inside the plants, at exhaust outlets and plant boundaries was examined to determine the comprehensive odor performance, critical components, and odor elimination efficiencies of various odor control engineering. Analytical results identified 29 compounds, including ammonia, amines, acetic acid, and multiple volatile organic compounds (VOCs) (hydrocarbons, ketones, esters, terpenes and S-compounds) in the odor from food waste composting plants. Concentrations of six components--ammonia, amines, dimethyl sulfide, acetic acid, ethyl benzene and p-Cymene--exceeded human olfactory thresholds. Ammonia, amines, dimethyl sulfide and acetic acid accounted for most odors compared to numerous VOCs. The results also show that the biotrickling filter was better at eliminating the concentrations of odor, NH(3), amines, S-compounds and VOCs than the chemical scrubber and biofilters. All levels measured by olfactometry at the boundaries of food waste composting plants (range, 74-115 Odor Concentration (OC)) exceeded Taiwan's EPA standard of 50 OC. This study indicated that the malodor problem continued to be a significant problem for food waste recovery.     

污泥堆肥动力学分析及工程启示

主要分析了堆肥体中物料的固、液、气三相及其界面的反应和传质过程,从微观动力学角度进行模拟计算,并分析了堆体内的反应、传质和传热过程,由此揭示污泥堆肥过程的影响因素及相互关系。通过计算分析堆肥过程动力学的控制因素,提出污泥堆肥工程优化的原则。     

生活垃圾好氧堆肥过程中氧浓度的变化规律及其应用

通过对堆层中氧浓度的测试,考察了微生物对氧的摄取规律,提出了通风量的确定方法以及最大耗氧速率的测试方法,并将其表征垃圾堆肥的稳定程度.结果显示,不同阶段、不同氧浓度对反应速率有很大影响;根据最大耗氧速率选取最佳通风量,可大大降低能耗;采用最大耗氧速率表征垃圾堆肥稳定程度具有较高的可信度.     

垃圾渗滤液微生物循环接种强化堆肥工艺与设计

针对垃圾堆肥过程中外加菌剂接种后活性衰退的问题以及我国小城镇有机垃圾的特点，开发了垃圾渗滤液微生物循环接种强化堆肥工艺。介绍了该工艺的基本原理、特点及垃圾渗滤液微生物循环培养方法。结合工程设计，介绍了工艺系统组成、主要设计参数、主要建（构）筑物设计以及主要技术经济指标。     

Food waste conversion options in Singapore: Environmental impacts based on an LCA perspective

Proper management and recycling of huge volumes of food waste is one of the challenges faced by Singapore. Semakau island — the only offshore landfill of the nation — only accepts inert, inorganic solid waste and therefore a large bulk of food waste is directed to incinerators. A remaining small percent is sent for recycling via anaerobic digestion (AD), followed by composting of the digestate material. This article investigates the environmental performance of four food waste conversion scenarios — based on a life cycle assessment perspective — taking into account air emissions, useful energy from the incinerators and AD process, as well as carbon dioxide mitigation from the compost products derived from the digestate material and a proposed aerobic composting system. The life cycle impact results were generated for global warming, acidification, eutrophication, photochemical oxidation and energy use. The total normalized results showed that a small-scale proposed aerobic composting system is more environmentally favorable than incinerators, but less ideal compared to the AD process. By making full use of the AD's Recycling Phase II process alone, the Singapore Green Plan's 2012 aim to increase the recycling of food waste to 30% can easily be achieved, along with reduced global warming impacts.     

公路隧道明洞结构计算方法

简单介绍了公路隧道明洞结构的建模方式和荷载组合工况及截面验算方法,并结合具体工程实例进行了计算和分析,得出了有益的结论,为工程设计提供了一定指导。     

路桥污水处理厂污泥好氧堆肥资源化利用工程

台州路桥污水处理厂脱水污泥产量为30m^3／d，含水率为80％。采用自主研发的半干化工艺处理后，污泥的含水率为50％～60％。再经过好氧堆肥处理可使污泥进一步减量化、稳定化和无害化，并有利于进行资源化利用。