天津市餐厨垃圾回收现状与对策

餐厨垃圾是一种具有较高再生利用价值的资源,但是处置不当会给社会造成危害。天津市餐厨垃圾的回收包括规范化的再生资源回收企业回收、以养猪和炼制餐厨再生食用油为目的的非法回收商贩回收、城市普通生活垃圾收集处理系统回收等三种形式。以源头单独集中、清洁化单独收运、无害化处理和资源化利用为指导原则,开展城市餐厨垃圾的规范化回收符合发展循环经济的根本要求。从加强宣传教育、加大食用油监管力度、健全行政监管体系、完善餐厨垃圾规范化收集网络等角度,提出推动天津市餐厨垃圾回收规范化发展的对策。     

循环经济模式下重庆市餐厨垃圾回收体系构建研究

随着人民生活水平的提高,生活节奏的加快,城市餐厨垃圾产生量也日益巨增,作为城市生活垃圾的重要组成部分,其餐厨垃圾的回收处置已经成为当前国内城市生活垃圾管理的重要课题。首先从餐厨垃圾的产生现状、收集现状、运输现状三方面分析重庆市餐厨垃圾处理存在的问题,其次,结合循环经济的理念及国内外餐厨垃圾的处理经验,构建政府建设—企业经营—产权转让的新型BOT餐厨垃圾回收模式,最后,对这种模式可能导致的经济行为进行情景假设分析,得出重庆市政府在BOT餐厨垃圾回收模式情景下,将更有利于美丽城市建设的结论。     

县级餐厨垃圾协同处置的工程应用

随着国家垃圾分类政策及制度逐渐完善,生活垃圾焚烧厂原物料中餐厨垃圾部分亟需配套处理设施。某县级市建设的垃圾综合处理发电项目,集生活垃圾焚烧、污泥干化、餐厨垃圾和粪便处理为一体,工艺系统联通,实现多种垃圾的协同处置。其中餐厨垃圾以“固液分离+油水分离”为核心的工艺路线,经处理后实现固、液、油分离,固相废弃物输送至焚烧系统进行协同焚烧处理;液相废弃物油脂分离后,初级油脂作为生物柴油原料外销;废水输送至渗沥液处理系统协同处理。相较于独立设厂,建设造价及运营成本明显降低,实现经济效益与环境保护共赢。     

厌氧消化处理餐厨垃圾技术进展

结合了国内外餐厨垃圾厌氧消化的研究现状,主要介绍了餐厨垃圾的消化体系特点、添加剂、联合消化等工艺条件对餐厨垃圾厌氧消化的影响,旨在探讨更有效的餐厨垃圾厌氧消化工艺条件,实现餐厨垃圾减量化,从无害化转向资源化和能源化。     

城市餐厨垃圾资源化技术应用现状与展望

介绍了餐厨垃圾的主要特点,列举了国内外城市餐厨垃圾的处理现状和主要资源化利用技术,分析主要技术的优势和劣势,对主要技术综合环境效益、经济效益和能耗等方面进行比较,得出厌氧消化等综合处理工艺较适合用于处理城市餐厨垃圾的结论,最后就餐厨垃圾处理设施规划中3个关键问题,即技术设计、产品销路和物流供应作了相应讨论。     

浅谈我国餐厨垃圾的回收与利用

随着我国经济发展及城镇化进程的加速,餐厨垃圾产生量近些年迅猛增长,餐厨垃圾的回收与资源化利用已成为解决城市环境问题的重要环节.对我国餐厨垃圾的回收与利用现状进行综述性分析,在此基础上提出了相应的对策和建议.     

发达国家餐厨垃圾回收利用经验及借鉴

介绍了发达国家回收处理和再利用餐厨垃圾的管理和技术,提出我国应借鉴发达国家经验,从技术、政策、法规等方面加强餐厨垃圾的再利用工作。     

餐厨垃圾脱液预处理技术及装备设计

餐厨垃圾脱液预处理对餐厨垃圾的有效处置具有重要作用。利用螺旋挤压固-液分离技术对餐厨垃圾进行脱液处理研究,分析螺旋挤压过程中的影响因素对脱液过程的影响。对研究结果进行总结,设计一台用于处理餐厨垃圾的综合处理装备,并在样机设备上对实际餐厨垃圾进行螺旋挤压脱液处理,对比分析不同螺旋转速和物料状态对脱水过程的影响。实验研究结果和实际使用状况用于评价设备的使用效果。     

小型餐厨垃圾处理设备的应用研究

简要概述了餐厨垃圾的定义及其常规处理方法,介绍了小型餐厨垃圾处理设备的工艺流程和工作原理。此设备基于高温好氧发酵作用,主要利用微生物将餐厨垃圾中的有机物等分解,对过程中产生的废气利用生物+吸附联合净化,从而达标排放。通过对小型餐厨垃圾设备进行试验研究,结果表明,此设备的垃圾降解率约为80%,针对餐厨垃圾产生量小的场合较为适用。     

餐厨垃圾制备生物柴油工艺研究

分析利用餐厨垃圾生产生物柴油的现状及发展趋势,对餐厨垃圾生产生物柴油存在问题及对策进行探讨。     

浅议碳排放与废钢铁的节能减排功效

二氧化碳是导致全球气候变暖、人类生存环境恶化的主要原因。简要介绍世界钢铁工业二氧化碳排放情况,针对我国钢铁工业碳排放的具体情况,提出发展我国废钢产业,提高废钢铁的供应能力,是我国钢铁工业摆脱危机,实现低碳发展、绿色发展的主要途径。     

资源循环科学与工程专业课程体系优化与教学内容创新实践的探索

针对资源循环科学与工程本科专业课程教学,以西安建筑科技大学该专业课程体系为案例,通过对毕业生和专业研讨会调研,分析了课程体系建设的现状和存在的问题。借鉴其他高校资源专业的课程体系和教学内容,通过梳理各门专业课程的教学内容和相互联系,构建了资源专业课程体系课程群,探索了课程体系优化的方法和增加创新实践环节的具体措施。     

Synthesis and identification of graft copolymers of wood pulp and styrene

Based on the graft copolymerization reactions of lignin and vinyl monomers, a series of graft copolymers of wood pulp and styrene (1-phenylethene) has been synthesized. The wood pulps used in this research are unbleached products produced by chemical, thermal, and mechanical pulping. All of them contain a high content of lignin (25–29 wt%). The grafting reaction is a free radical polymerization coinitiated by calcium chloride, hydrogen peroxide, and wood pulp in dimethylsulfoxide at 30°C. The effect of reaction temperature, reaction time, and the amount of the reactants on the conversion of monomer, yield of product, weight increase of pulp, and grafting efficiency of monomer has been studied. The grafted wood pulp was separated from homopolystyrene formed during the reaction by extraction of the reaction product with benzene in a Soxhlet apparatus for at least 48 h. The results show that after the reaction, the weight of all wood pulps was significantly increased and the weight increase of very high yield sodium bisulfite pulp (VHYS) was 333%. This proves that a part of the polymerized styrene was chemically bound to the wood pulp. The Fourier transform infrared (FTIR) spectra of the extracted products show absorbance peaks characteristic of both wood and polystyrene and, thus, provide strong proof of grafting. Grafting has completely changed the surface properties of the starting wood pulp from hydrophilic to hydrophobic, and under ordinary thermal compression conditions, thermoplastic composite objects of good uniformity can be made directly from reaction products which contain up to 52 wt% wood pulp.     

Fate and effect of linuron and metribuzin on the co-composting of green waste and sewage sludge

The fate and effect of the herbicides linuron and metribuzin on the co-composting of sewage sludge and green waste were addressed in this work. The experiments were conducted in metal cubic containers of 1.0 m³ volume simulating a windrow composting system. A mixture of sludge and green waste was prepared at a ratio of 1:5 v/v. The mixture was split in four equal parts and the two herbicides were added, using a pressure sprayer, as sole or mixed pollutant in each of the three mixtures. The forth mixture was composted without any addition of herbicide, to serve as control. Temperature, physicochemical characteristics, herbicide concentration, carbon dioxide emission, methane emission and microbiological parameters were measured either daily or every time the mixtures were turned, for a period of 80 days. Both herbicides’ concentration decreased significantly resulting in removal efficiencies of 99.1–99.7% and 95.8–96.0% for linuron and metribuzin, respectively. Incubation of microbiologically inactive mixtures at a temperature schedule following the spontaneous temperature evolution in the composters resulted in very little (1–11%) decomposition for both herbicides. Comparison of the variation of physicochemical parameters and microbial populations during composting indicated that both herbicides did not affect the composting process.     

Photo-oxidation and Photo-toxicity of Crude and Refined Oils

The fate and effects of an oil spill are effected by solar radiation through the action of photo-oxidation and photo-toxicity. Photo-oxidation, an important process in the weathering of oil, produces a variety of oxidized compounds, including aliphatic and aromatic ketones, aldehydes, carboxylic acids, fatty acids, esters, epoxides, sulfoxides, sulfones, phenols, anhydrides, quinones and aliphatic and aromatic alcohols. Some of these compounds contribute to the marine biota toxicity observed after an oil spill. Photo-toxicity occurs when uptake of certain petroleum compounds, e.g. certain polycyclic aromatic hydrocarbons and benzothiophenes, is followed by solar exposure which results in much greater toxicity than after dark uptake. The mechanism of PAH photo-toxicity includes absorbance of solar radiation by the PAH which produces a free radical and this free radical in turn reacts with oxygen to produce reactive oxygen species that can damage DNA and other cellular macromolecules. While most studies on photo-toxicity have been carried out in the laboratory, there are studies showing that water from an oil spill is photo-toxic to bivalve embryos for at least a few days after the spill. Other studies have found that oil contaminated sediments are photo-toxic to several marine invertebrates. More studies are required to determine if marine fauna at an oil spill site are effected by the action of photo-toxicity and photo-oxidation.     

我国废旧电子电器产品拆解技术、设备应用现状及改进建议

从我国废旧电子电器回收行业基本情况、专业技术人才情况、相关企业拆解技术设备情况等方面,阐述了我国废旧电子电器产品拆解技术、设备应用现状,并提出相关改进提升建议。     

Laboratory Experiments and Estimation of Cumulative Infiltration and Sorptivity

Soil water cumulative infiltration affects the environment by controlling the irrigation rate and consequently the water and pollutants movement through the ground. In order to study the cumulative infiltration in a sandy soil sample, experiments were performed in the laboratory. The sample was placed uniformly in a transparent column with an inner diameter of 6 cm. A constant head boundary condition of a 2 mm height was applied on the surface of the sample and the cumulative volume of the incoming water was measured. Soil moisture at four locations of the column was measured, by using the TDR method in order to obtain the moisture profiles. By comparing the values of the infiltrated water volumes with those calculated by the integration of the moisture profiles, a good agreement was found out. Also the Parlange theoretical model fitted very well with the infiltration experimental points.     

硫磺回收装置扩能改造及效果分析

介绍了回收酸性气体生产硫磺的工艺原理与工艺流程,论述了影响硫磺回收装置生产能力的诸多因素与扩能改造的情况。扩能改造后,该装置的酸性气体处理量平均为976m^3／h,瞬时处理量可达1200m^3／h,硫磺的生产能力从4450t／a提高到7500t／a,生产能力提高了68．5％,装置总硫回收率达到93．5％。     

电子废弃物的再循环利用:企业、政府与公众的角色和责任

电子废弃物不仅种类繁多,而且成分复杂,含有多种有毒、有害物质,已成为固体废物中最大的重金属污染源.长期以来,由于对电子废弃物问题缺乏足够认识和有效管理,电子废弃物对人体健康及生活环境可能构成的危害常常被忽视.实现电子废弃物的再循环利用,关键是明确企业、政府和公众在电子产品设计、生产、消费、回收、处置和再利用整个过程中的相关责任.因此,解决电子废弃物的问题,首先要对相关行为主体的角色进行准确定位.     

TEMPO-Mediated Oxidation of Norway Spruce and Eucalyptus Pulps: Preparation and Characterization of Nanofibers and Nanofiber Dispersions

This study deals with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of cellulose. Softwood and hardwood pulp fibers were suspended in water and oxidized to various extents at pH 10 and 22 °C using sodium hypochlorite in the presence of TEMPO radical and sodium bromide. This reaction system is known to be the most efficient one for the introduction of both surface carboxyl and aldehyde groups. Important relationships between formation of these functional groups and the fibrillation yield, light transmittance of the water dispersions and degree of polymerization of the oxidized softwood and hardwood pulps were established in the present study. A birefringence test confirmed the presence of nanofibers which according to atomic force microscopy analyses had diameters in the 1.6–3.8 nm range.