城市生活垃圾堆酵实验研究

垃圾焚烧处理技术在中国方兴未艾。但由于气候，生活水平和生活习惯的差异，中国的城市生活垃圾与西方的生活垃圾相比存在含水率高，垃圾热值较低的特点，垃圾在入炉前需要在炉前的垃圾池中进行一段时间的堆放，以尽可能渗出其中的水分，提高入炉垃圾的单位热值。垃圾不同于一般燃料，在堆放的过程中不但会有一些物理过程变化，还会发生一系列的生化反应，导致垃圾的成分特性发生变化，改变垃圾的燃料特性，从而对垃圾在炉内的燃烧状况产生明显的影响。本文通过建立实验平台模拟垃圾池中的环境，对原始垃圾进行一段时间的堆酵实验，从而得出垃圾水分及热值随堆酵条件（主要是时间）变化的情况，分析堆酵条件对垃圾燃料特性及炉内燃烧过程的影响。为中国垃圾焚烧厂堆酵工艺提供依据。     

提高生活垃圾热值的有效途径——厦门市城市生活垃圾热值初探

通过对厦门市城市生活垃圾的热值、成分、含水率的测定,分析影响垃圾热值的因素;并对垃圾筛上物以及未筛分垃圾进行比对实验.结果表明:垃圾筛分后筛上物的含水率明显降低,热值大大提高.垃圾筛分是提高垃圾热值的有效途径.     

苏州市生活垃圾特性分析及处理对策

对苏州市压缩式中转站压缩后的生活垃圾以及散装垃圾的成分、含水率和热值进行测定,分析热值和物理特性的关系、压缩对垃圾含水率和热值的影响,进一步对苏州市近10 a的生活垃圾特性变化进行分析,提出苏州市垃圾处理的建议.     

大型垃圾填埋场陈腐垃圾成分特性及开采利用研究——以江苏省某市生活垃圾填埋场为例

以江苏省某市生活垃圾填埋场为例,通过勘探取样,分析了该填埋场近几年陈腐垃圾的成分特性,陈腐垃圾有机质含量高,湿基低位热值为4 114.7～4 872.7 kJ/kg,可燃物占比为77.33%～80.69%,具有较大的开发利用价值。同时分析探讨了陈腐垃圾的开采及综合利用方法,结合现场提出了填埋场开发利用规划展望。     

我国城市生活垃圾焚烧发电厂垃圾热值分析

在收集和整理大量炉排炉垃圾焚烧发电厂运营数据的基础上,对我国多个地区生活垃圾焚烧厂垃圾热值进行了估算,并分析了不同地区、运营时间以及工业发展水平等对焚烧厂生活垃圾热值的影响。分析发现:垃圾焚烧厂生活垃圾热值逐年增加;不同地区的生活垃圾热值差别明显,呈现南高北低、东高西低的变化趋势;工业增加值较高的城市其生活垃圾热值也相对较高。     

武汉市城市生活垃圾组分变化的主成分分析

利用主成分分析的数学方法对1984－2000年武汉市城市生活垃圾组分变化进行了主成分分析,分析结果表明：（1）影响城市生活垃圾组分变化的主要有煤灰、厨渣、果皮、塑料和纸张;（2）垃圾湿基低位热值月份间差别不是很显著,年间变化增长速度较快;（3）城市生活垃圾可回收废物中,纸张、塑料、玻璃和毛骨的变化率较大且呈增长趋势。     

非正规生活垃圾填埋场矿化垃圾资源化利用技术——以东莞市非正规垃圾填埋场为例

以东莞市非正规垃圾填埋场为例,研究了矿化垃圾的组成成分,结果表明:非正规垃圾填埋场矿化垃圾中腐殖土和可燃物占50%以上,且腐殖土中重金属Cd含量高,不能作为农用,宜作为园林绿化土壤使用;经分选后的可燃物热值较高,宜深加工成垃圾衍生燃料(RDF);并讨论了腐殖土的综合利用和垃圾衍生燃料(RDF)的制造工艺技术。     

都江堰市城市生活垃圾调查与分析

通过对都江堰市生活垃圾的成分和理化性质分析,认为都江堰市生活垃圾主要来源于家庭和各种商业活动,热值基本满足垃圾焚烧处理要求。     

我国南方村镇生活垃圾组分热值特征及焚烧处置潜力分析

为了解我国南方村镇生活垃圾的基本性质及其采取焚烧处置的可行性,于2015年的4个季节,对我国南方36个典型村镇生活垃圾产生源进行分析,研究其垃圾组分的含量(湿基)、含水率及热值。研究结果为:我国南方村镇生活垃圾湿基组分由高到低为厨余类灰土类橡塑类纸类织物类砖瓦类玻璃类木竹类金属类有害类。南方村镇生活垃圾全组分含水率均值为(40.1±5.2)%。生活垃圾全组分低位热值为(4 152.3±1 911.1)k J/kg,生活垃圾经分选后,虽然整体生活垃圾可燃组分低位热值得到提高,但仍存在部分可燃组分的低位热值达不到要求。为此,南方村镇生活垃圾在采取焚烧处置时需加强管理,加强垃圾稳定化以降低含水率。     

城市垃圾管理工作中的季节性因素的影响

以湖北省的部分城市为例，阐述了因素对对城市垃圾产量及成分的影响：产量从高到低依交伙３了度、４季度、２季度、１季度；易腐垃圾成分峰值出现在夏季，无机垃圾成分峰值出现在冬末，春初。同时，对季节性因素的影响进行分析，并提出调控季节性因素的对策与措施。     

堆肥处理生活垃圾是水网平原城市的最佳选择

水网平原地区人多地少,土地高度垦殖,地质条件差,地下水位高,传统处理垃圾给周围环境带来严重污染。焚烧处理投资大,目前垃圾本身热值低,需加添加剂,造成运转成本高。填埋处理场地选择十分困难,只能从堆肥上寻出路。常州环境卫生综合厂是工厂式综合性处理生活垃圾的模式,它不仅适用于水网平原地区城市生活拉圾处理,而且适合经济发达的中小城市和乡镇。     

Evaluation of medical waste incinerators in Alexandria

Medical establishments play important roles in different activities by using of modern technology to serve the humans and the environment through different departments in the establishment and its firms. Medical wastes are considered as a hazardous waste because they contain toxic materials, infectious, or non-infectious wastes and they are considered as a hazard to millions of patients, health care workers, and visitors. Treatment processes for medical wastes comprise autoclaving, microwaving, chemical disinfection, irradiation, plasma system, and incineration. Incineration is a thermal process, which destroys most of the waste including microorganisms. Combustion process must be under controlled conditions to convert wastes containing hazardous materials into mineral residues and gases. Hospital waste incinerators may emit a number of pollutants depending on the waste being incinerated. These pollutants include particulate matter, acid gases, toxic metals, and toxic organic compounds products of incomplete combustion, e.g., dioxins, furans, and carbon monoxide, as well as sulfur oxides and nitrogen oxides. So, there should be a reduction of emissions of most of these pollutants by air pollution control devices. This study was conducted in 51 medical establishments (ME) in Alexandria. To evaluate its incinerators. It was found that only 31.4% of total ME have their own incinerators to treat their medical waste. Also, the incinerators conditions were poor with incomplete combustion. So, the study recommend handling of all medical wastes of ME in Alexandria by the company which is responsible now for management of domestic solid wastes of the city.     

Management of waste disposal in medical institutions

Recently new regulations were elaborated for the management of medical wastes in Austria, FRG, Canada and USA. There is no rule laying down the requirements of the management of medical wastes in Hungary. On the basis of foreign experiences the medical wastes are proposed to range into categories as follow: I. Waste that should be handled in special way within and outside the health care facilities. II. Waste, that should be handled in a special way within the health care facilities. III. General waste (municial-type waste). Basic requirement is the segregating collection of wastes. Color-coding is proposed to identify the content of containers and bags. Incinerators combined with pyrolysis and emission control unites should be preferred to the disposal of medical wastes. The author proposes to issue a rule setting out definitions and basic principles of management of medical wastes. Individual health care establishments should prepare own written policies and measures for waste handling appropriate to their specific requirements.     

Microbiological characterization of solid wastes and aerosol in a municipal solid waste landfill site

Authors report data about microbiological characterization of solid wastes and aerosol in the municipal solid waste landfill site in Poiatica (RE). In solid waste samples high values of total coliform and fecal coliform were observed (10(5)-10(6) CFU/g): total bacterial counts at 22 degrees, at 36 degrees and at 44 degrees ranged from 10(7) to 10(9) CFU/g. Aerosol samples collected during waste movement in the landfill site showed values of total and fecal bacterial ranging from 10(3)-10(4) CFU/m3. Staphylococci and fungi reported the same values while streptococci, total and fecal coliform and spore evidenced lower values. Municipal solid wastes and aerosol have to be considered as an infective substrate: it is necessary to adopt protective barriers in occupationally exposed subjects.     

Feeding inhibition in the soil collembolan Folsomia candida as an endpoint for the estimation of organic waste ecotoxicity

Despite the increasing quantities of organic wastes that are being reused in soils, there are few studies that focus on the selection of bioassays for the ecotoxicological risk assessment of organic wastes to soils. In the present study, differences in feeding inhibition in the soil collembolan Folsomia candida were evaluated as an ecotoxicological endpoint for the assessment of risk to soils amended with polluted organic wastes. Seven organic wastes (dewatered sewage sludges, thermally dried sewage sludges, composted sewage sludges, and a thermally dried pig slurry) were tested. These wastes had different origins, treatments, and pollutant burdens, and were selected as a representative sample of the wide variety of wastes currently generated. A clear dose response was observed for this parameter, with an increase in percentage of individual feeding inhibition with increased doses of organic wastes. More significantly, feeding inhibition correlated highly with mortality and reproduction inhibition in the different wastes. Composted sludges displayed the lowest toxicity, followed by thermally dried sludge and dewatered sludge. Thermally dried pig slurry showed the highest toxicity for feeding, with lower median effective concentration (EC50) values than the lowest dose tested. Among waste physicochemical parameters and pollutants, low organic matter stability appeared to be the main predictor of potential adverse effects on soil fauna, because it correlated significantly with feeding inhibition and mortality. Furthermore, feeding inhibition tests were run over a short exposure time (less than 7 d), which, together with the results obtained, makes this bioassay a good screening tool for organic waste toxicity.     

A study of the leachate toxicity of metal-containing solid wastes using Daphnia magna

This paper examines the ecotoxicity of different actual inorganic wastes containing some potentially toxic metals commonly found in many industrial residues and the reduction in ecotoxicity obtained when the wastes are submitted to a solidification/stabilization process. The ecotoxicity was assessed as defined in the Spanish regulations on hazardous wastes, by means of the Daphnia magna Straus acute toxicity test applied to the toxicity characteristic leaching procedure (TCLP) waste leachate. On the basis of the EC50 values of the individual metals and the effect of the pH of the aqueous medium on D. magna, we have explored a method for estimating the toxicity of the TCLP waste leachate by calculating its EC50 value in the D. magna test. Although the method is only valid in cases in which a clear cause for the toxicity exists, the procedure described allows us to more completely explain the observed effects on the daphnids. The ecotoxicity of the residues after stabilization is less than that of the untreated waste, generally as a consequence of the reduction in metal leachability achieved by the immobilization treatment. The stabilization process was analyzed in terms of both the chemical and the ecotoxicological parameters, and the influence of leachate pH on the objectives of waste treatment is discussed.     

Nutritional Content and Antioxidant Properties of Pulp Waste from Daucus carota and Beta vulgaris

This study reports the chemical composition and antioxidant potential of pulp waste from two vegetables, carrot (Daucus carota) and beetroot (Beta vulgaris). Different in vitro assays used for determining antioxidant potential of extracts of pulp wastes were: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, reducing power and total antioxidant activity by phosphomolybdenum method. Total polyphenols, tannins and antioxidative components such as vitamin C, total carotenoids and β-carotene were analysed in the samples. The moisture content of samples ranged from 79 - 84%. The protein content was high in beetroot (13.23 mg/100g) and low in carrot (6.21mg/100g). Total polyphenols were higher in methanol extracts of samples (220-250 mg/100g) compared to ethanol and aqueous extracts. The antioxidant activity determined by the DPPH method exhibited 40% and 78% activity in methanol extracts of carrot and beetroot pulp waste (20 mg) respectively. Overall, the results suggest that carrot and beetroot pulp wastes can be exploited for their nutrients and antioxidant components and used for value addition in food formulations. Hence, these results pave the way for utilisation of bio-wastes from the food industry.     

Dental waste management in municipal health clinics in Belo Horizonte, Brazil]

OBJECTIVE: To investigate whether municipal health clinics in the city of Belo Horizonte, Brazil, comply with the legal requirements for managing dental wastes. METHOD: We collected information from 54 of the city's 105 municipal health clinics that provide dental care. At each clinic we interviewed the clinic manager, one dental assistant, and one general assistant. Based on the requirements outlined in the Belo Horizonte Health Waste Management Manual, we assessed characteristics in the following three areas: (1) technical and operational (waste classification and characterization, minimization, segregation, pretreatment, conditioning, collection and internal and external transportation, and external storage); (2) general and organizational (inspection, amount of clinic space, environmental permits, floor plan showing waste-generating areas, and whether the clinic had a technical specialist responsible for managing the health wastes); and (3) human resources (employee vaccination records and oversight, occupational safety and occupational medicine program, environmental risk prevention program, medical oversight and occupational health program, hospital (clinic) infection control committee, and training in health waste management). RESULTS: The clinics produced an average of 270 liters of solid waste per day. None of the clinics surveyed had a plan for managing health wastes. The only requirements with which all the clinics complied were: segregation of needles and mercury, adequately identified cardboard containers used for disposal of cutting and piercing items, and daily internal collection and transportation of wastes. CONCLUSIONS: When the risks associated with each class of waste have not been established, all the wastes should be considered potentially dangerous. Further, a law by itself does not guarantee that the public's health will be protected. Before public agencies impose legal requirements, it is necessary to know if the agencies themselves are capable of enforcing those requirements. Any proposed waste management legislation should be based on scientific research.     

Fenton试剂处理垃圾渗滤液技术进展的研究

介绍了垃圾渗滤液的危害及毒性,比较了用活性碳吸附、FeCl、絮凝、Fenton试剂中H2O2和FeSO4的不同比例处理垃圾渗滤液的工艺流程以及对COD处理效果的影响讨论了pH、温度、反应时间、Fenton试剂不同配比对处理效果的影响,得出用Fenton试剂处理垃圾渗滤液时,可把大分子的有机物氧化为小分子,从而降低了垃圾渗滤液的COD值,对分子量较小的有机物的去除率不高。     

Applying Nightingale charts to evaluate the heterogeneity of biomedical waste in a Hospital

OBJECTIVES:

to evaluate the heterogeneity of biomedical waste (BW) using Nightingale charts.

METHOD:

cross-sectional study consisting of data collection on wastes (direct observation of receptacles, physical characterisation, and gravimetric composition), development of a Management Information System, and creation of statistical charts.

RESULTS:

the wastes with the greatest degree of heterogeneity are, in order, recyclable, infectious, and organic wastes; chemical waste had the most efficient segregation; Nightingale charts are useful for quick visualisation and systematisation of information on heterogeneity.

CONCLUSION:

the development of a management information system and the use of Nightingale charts allows for the identification and correction of errors in waste segregation, which increase health risks and contamination by infectious and chemical wastes and reduce the sale and profit from recyclables.