Greenhouse gas emission and its potential mitigation process from the waste sector in a large-scale exhibition

As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO₂-equivalent (CO₂-eq.), 4.43 kg SO₂-eq., 4.88 kg NO₃⁻-eq., and 3509 m³ water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO₂-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO₂-eq., and CH₄, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO₂-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.     

Greenhouse gas emission and its potential mitigation process from the waste sector in a large-scale exhibition

As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO₂-equivalent (CO₂-eq.), 4.43 kg SO₂-eq., 4.88 kg NO₃^--eq., and 3509 m³ water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO₂-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO₂-eq., and CH₄, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO₂-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.     

Resources and waste management in Turin (Italy): the role of recycled aggregates in the sustainable supply mix

The ever increasing quantity of construction and demolition waste (C&DW) in Italy is presently challenging public administrators, which strive to ensure that collection and recycling are sustainably managed and need to understand whether and to what extent recycled aggregates can complement natural aggregates in a sustainable supply mix (SSM) for the construction industry. The paper presents a research aimed at analysing energy and environmental implications of the C&DW recycling chain in the administrative territory of Provincia di Torino in Northern Italy, with 2.25 million inhabitants and yearly generation of 1.8 million tons of C&DW. A combined Geographical Information System (GIS) and Life Cycle Assessment (LCA) model was developed using site-specific data and paying particular attention to land use, transportation and avoided landfill: crucial issues for sustainable planning and management. A GIS was used to handle data and information about 89 recycling plants, including technological features, output and physical–mechanical characteristics of recycled aggregate. The LCA methodology was used to identify and quantify energy and environmental loads, under different assumptions relevant to delivery distances, quality of recycled aggregates, local availability of natural aggregates and geographical coverage of market demand. The C&DW recycling chain was proved to be eco-efficient, as avoided impacts were found to be higher than the induced impacts for 13 out of 14 environmental indicators. It was also estimated that the transportation distance of recycled aggregate should increase 2–3 times before the induced impacts outweigh the avoided impacts.     

废旧聚氯乙烯再生过程生命周期评价

生命周期评价是对产品、生产工艺以及活动对环境的压力进行评价的客观过程.运用生命周期评价方法,对我国南方某公司废旧聚氯乙烯再生过程的资源消耗和环境影响进行量化估算.结果表明:1 t废旧聚氯乙烯再生的总能源消耗量为6 287 MJ,其中石油消耗量为6 000 MJ,煤消耗量为287 MJ,总的资源耗竭系数为5.77×10-3 a;废旧聚氯乙烯再生的环境影响负荷为0.428 a-1,其中废塑料运输过程主要引起光化学臭氧合成问题,其环境影响潜值为0.190 a-1;工艺过程中主要引起固体废物污染,其环境影响潜值为0.110 a-1.废旧聚氯乙烯再生的主要环境影响为光化学臭氧合成、固体废物、大气颗粒物污染和酸化.      

Life cycle assessment of spray dried soluble coffee and comparison with alternatives (drip filter and capsule espresso)

This paper aims to evaluate the environmental burdens associated with spray dried soluble coffee over its entire life cycle and compare it with drip filter coffee and capsule espresso coffee. It particularly aims to identify critical environmental issues and responsibilities along the whole life cycle chain of spray dried coffee. This life cycle assessment (LCA) specifically uses foreground data obtained directly from coffee manufacturers and suppliers. Aside from energy consumption and greenhouse gases emissions, water footprint is also studied in detail, including regionalization of water impacts based on the ecological scarcity method 2006. Other impact categories are screened using the IMPACT 2002+ impact assessment method.The overall LCA results for a 1 dl cup of spray dried soluble coffee amounts approximately to 1 MJ of primary non-renewable energy consumption, to emissions of 0.07 kg of CO_2-eq, and between 3 and 10 l of non-turbined water use, depending on whether or not the coffee cultivation is irrigated and wet treated. When considering turbined water, use can be up to 400 l of water per cup. Pouch – and to a lesser extent metal can packaging alternatives – show lower environmental burdens than glass or sticks.On average, about one half of the environmental footprint occurs at a life cycle stage under the control of the coffee producer or its suppliers (i.e., during cultivation, treatment, processing, packaging up to distribution, along with advertising) and the other half at a stage controlled by the user (shopping, appliances manufacturing, use and waste disposal). Key environmental parameters of spray dried soluble coffee are the amount of extra water boiled and the efficiency of cup cleaning during use phase, whether the coffee is irrigated or not, as well as the type and amount of fertilizer used in the coffee field. The packaging contributes to 10% of the overall life cycle impacts.Compared to other coffee alternatives, spray dried soluble coffee uses less energy and has a lower environmental footprint than capsule espresso coffee or drip filter coffee, the latter having the highest environmental impacts on a per cup basis. This study shows that a broad LCA approach is needed to help industry to minimize the environmental burdens directly related to their products. Including all processes of the entire system is necessary i) to get a comprehensive environmental footprint of the product system with respect to sustainable production and consumption, ii) to share stakeholders responsibility along the entire product life cycle, and iii) to avoid problem shifting between different life cycle stages.     

Attributional life cycle assessment of woodchips for bioethanol production

Besides the apparent need to reduce greenhouse gas emissions, other important factors contributing to the renewed interest in biofuels are energy security concerns and the need of sustainable transportation fuel. Nearly 30% of the annual CO₂ emissions in the U.S. come from the transportation sector and more than half of the fuel is imported. Biofuels appear to be a promising option to reduce carbon dioxide emissions, and the reliance on imported oil concomitantly. The interest on (ligno) cellulosic ethanol is gaining momentum as corn-based ethanol is criticized for using agricultural outputs for fuel production. Among many lignocellulosic feedstocks, woodchips is viewed as one of the most promising feedstocks for producing liquid transportation fuels. The renewable and carbon neutral nature of the feedstocks, similar chemical and physical properties to gasoline, and the low infrastructure cost due to the availability of fuel flex vehicles and transportation networks make (ligno) cellulosic bioethanol an attractive option. An in-depth LCA of woodchips shows that harvesting and woodchips processing stage and transportation to the facility stage emit large amount of environmental pollutants compared to other life cycle stages of ethanol production. Our analysis also found that fossil fuel consumption and respiratory inorganic effects are the two most critical environmental impact categories in woodchips production. We have used Eco-indicator 99 based cradle-to-gate LCA method with a functional unit of 4 m³ of dry hardwood chips production.     

Development of a life cycle assessment tool for construction and maintenance of asphalt pavements

The increasing use of recycled materials in asphalt pavements calls for environmental assessment of such impacts as the energy input and CO₂ footprint. Life cycle assessment (LCA) is being accepted by the road industry for such purpose. It aims to quantify and collate all the environmental impacts from the life time of the product or process. This paper reviews relevant LCA resources worldwide, identifies the knowledge gap for the road industry, and describes the development of an LCA model for pavement construction and maintenance that accommodates recycling and up-to-date research findings. Details are provided of both the methodology and data acquisition. This is followed by a discussion of the challenges of applying LCA to the pavement construction practice, and recommendations for further work. In the case study, the model is applied to an asphalt paving project at London Heathrow Terminal-5 (LHR), in which natural aggregates were replaced with waste glass, incinerator bottom ash (IBA) and recycled asphalt pavements (RAP). Production of hot mix asphalt and bitumen was found to represent the energy intensive processes. This is followed by data analysis and sensitivity check. Further development of the model includes expanding the database to accommodate the recycling and maintenance practice in the UK, and taking into account the effect that roadwork has on traffic emissions. The LCA model can be further tested and calibrated as a decision support tool for sustainable construction in the road industry.     

Screening life cycle assessment (LCA) of tomato ketchup: a case study

A screening life cycle assessment (LCA) of tomato ketchup has been carried out. The purpose was to identify ‘hot-spots', that is parts of the life-cycle that are important to the total environmental impact. The system investigated includes agricultural production, industrial refining, packaging, transportation, consumption and waste management. Energy use and emissions were quantified and some of the potential environmental effects assessed. Packaging and food processing were found to be hot-spots for many, but not all, of the impact categories investigated. For primary energy use, the storage time in a refrigerator (household phase) was found to be a critical parameter.     

Reviewing the carbon footprint analysis of hotels: Life Cycle Energy Analysis (LCEA) as a holistic method for carbon impact appraisal of tourist accommodation

This study discusses the potential for Life Cycle Assessment (LCA) to be utilized for the environmental assessment of tourism accommodation facilities, and their contribution to global carbon footprint. To demonstrate the viability of employing LCA in the hotel sector, its simplified derivative, Life Cycle Energy Analysis (LCEA), is applied to two tourism accommodation facilities in Poole, Dorset (UK) to quantify their CO₂ emissions. The results indicate that the reviewed hotels are less energy and carbon-intense than the tourism accommodation establishments reported in the literature. This may indirectly imply the continuous progress of hotel’s energy efficiency over time. The implications of the current energy use practices in the reviewed hotels are discussed and suggestions are made on how to further improve the energy performance and therefore cut the carbon footprint. Recommendations for hotel management and policy-making are developed to reduce the energy and carbon intensity of the hotel industry. A method for energy and carbon footprint analysis of outsourced laundries and breakfast services is also proposed.     

LCA of spent fluorescent lamps in Thailand at various rates of recycling

This paper presents environmental impact of a fluorescent lamp (a long straight tube 36 watts, 200 g and 13,600 h for mean time before failure) when considering different disposal methods (recycle and non-recycle) of its spent fluorescent lamp (SFL). The study was applied for the case in Thailand using life cycle assessment (LCA) as a tool. All materials, energy use, and pollutant emissions to the environment from each related process were identified and analyzed. Impact assessment was conducted for 10 environmental impact potentials: carcinogens, respiratory organics, respiratory inorganics, climate change, radiation, ozone layer, ecotoxicity, acidification/eutrophication, land use and minerals. The analysis followed Eco-Indicator 99 method, individualist version 2.1. The main focus of the study was to compare the impact of SFL recycling with non-recycling before landfilling. The impact intermittent activities, production of raw material and energy used in all the concerned processes were taken into account. However, transportation activities were excluded. The results showed that for all recycling rates, cement production is the main contributor to the environmental impacts, while sodium sulfide production is second and electrical production, the third. Mercury vapor emission showed a small contribution in carcinogens and ecotoxicity. The impacts are reduced when recycling rate is increased. The reduction of cement consumption in disposal processes or the process improvement of cement production may also help to reduce environmental impacts.     

Analysis of the sustainability of reusing industrial wastes as energy source in the industrial sector of Taiwan

The objective of this paper was to provide a preliminary analysis of energy utilization from industrial waste in Taiwan, a densely populated island country with high dependence on imported energy. The discussion thus focused on the status of industrial waste generation and its management since the year 2002. This paper also presented the updated information about the new/revised regulations concerning the governmental regulations and policies for promoting industrial waste as energy source as well as controlling the emissions of hazardous air pollutants from industrial waste-to-energy facilities. It showed that the main types of combustible waste in the industrial sector of Taiwan include pulp sludge, scrap wood, sugarcane bagasse, textile sludge and scrap plastics, which were being reused as auxiliary fuel in the utilities (e.g., boiler and incinerator). Based on their reported quantities, the energy potential and the environmental benefit of mitigating CO₂ emissions were also analyzed in the study.     

Life cycle assessment of milk produced in two smallholder dairy systems in the highlands and the coast of Peru

Life Cycle Assessment (LCA) was applied to two smallholder milk production systems in Peru in order to evaluate the environmental burden of milk produced in each. An Andean highland milk production system where livestock feeding is restricted to permanent pastures supplemented with on farm grown ryegrass-clover was opposed to a coastal system with dairy cows fed a diet consisting of fodder maize and purchased concentrate. Milk production levels (kg/cow day) differed considerably with 2.57 for the highland and 19.54 for the coastal system. A Life Cycle Inventory was calculated for the functional unit of 1 kg energy corrected milk (ECM) and the environmental impacts global warming, acidification and eutrophication were estimated for 1 kg ECM, 1 ha and 1 animal, considering the multi-functionality of the system. The highland system was characterized by a high land use (23.1 m²a/kg ECM vs. 1.71 m²a/kg ECM at the coast). Irrigation water and energy were on the other hand used to a much higher amount at the coast (7291 l/kg ECM and 8791 MJ/kg ECM, respectively) than in the highlands (848 l/kg ECM and 0.20 MJ/kg ECM). Global warming potential, acidification and eutrophication were higher for 1 kg ECM produced in the highlands than at the coast by 10.6 kg CO₂ equivalents, 6.58 g sulfur dioxide equivalents and 10.63 g phosphate equivalents, respectively. Nevertheless, 5220 kg CO₂ equivalents more were emitted per animal at the coast than in the highlands. Also acidification and eutrophication were estimated to be on average 6 and 4 times higher at the coast compared to the highlands when expressed for the functional units of 1 ha and 1 animal.

Results

Whereas livestock is mainly responsible for impacts on the environment in the highlands, at the coast both livestock related emissions and forage cultivation play an important role. Furthermore CO₂ releases from soybean cultivations heavily contribute to total emissions. Sensitivity analysis indicates that for dairy systems relying on crop by-products as feed the choice of the allocation method is a crucial point in a LCA study. Based on the results of this study, strategies in order to reduce the environmental burden of milk production should focus on an increase of production levels and a reduction of methane emissions from enteric fermentation in the highlands and a modification of the concentrate components replacing soya as the protein source at the coast.     

A life cycle impact of the natural gas used in the energy sector in Romania

The world's natural gas consumption continues to grow, increasing its market share of total primary energy consumption. Among the major fuels, natural gas is expected to provide the greatest increase in energy consumption in the world energy sector, due to its relatively low environmental impact and high thermodynamic quality. Natural gas plays a significant role in the energy sector because of its environmental qualities and energy. We analyzed the natural gas life cycle by using the life cycle assessment (LCA) to compare, from an environmental point of view, four sites of heat production by natural gas combustion. We determined the best site from an environmental point of view for a consumer and which stage (extraction, treatment, transportation, storage, combustion) of the natural gas life cycle pollutes the most. This study confirmed the utility of the LCA in the evaluation of the environmental impact in the energy sector.     

中国氢燃料电池车燃料生命周期的化石能源消耗和CO2排放

氢燃料电池车(FCV)具有运行阶段高能效和零排放的优点,近年来得到快速的商业化发展.氢能生产具有多种技术路径,不同路径的能源和环境效益存在显著差异.本研究采用生命周期评价方法,运用GREET模型对不同氢燃料路径下的FCV燃料周期(WTW)的化石能源消耗和CO_2排放进行了全面评价.选取了多种制氢路径作为评价对象,建立了中国本地化的FCV燃料生命周期数据库,在此基础上分析了FCV相对传统汽油车的WTW节能减排效益,并和混合动力车和纯电动车进行比较.结果表明,使用可再生电力和生物质等绿色能源制氢供应FCV能取得显著的WTW节能减排效益,可削减约90%的化石能耗和CO_2排放.在发展相对成熟的传统能源制氢路径中,以焦炉煤气制得氢气为原料的FCV,能产生显著的节能减排效益,其化石能耗低于混合动力车,CO_2排放低于混合动力车和纯电动车.结合对资源储备和技术成熟度的考虑,我国在发展氢能及FCV过程中,近期可考虑利用焦炉煤气等工业副产物制氢,并且规划中远期的绿色制氢技术发展.     

Resource consumption and emissions from olive oil production: a life cycle inventory case study in Cyprus

“Cradle to gate” life cycle analysis (LCA) has been used to evaluate the consumption of raw materials and emissions of pollutants from olive oil production in Lythrodontas region in Cyprus, in order to identify the processes which give rise to the most significant environmental burdens. The system investigated includes the production of the chemical inputs used (fertilisers and pesticides), agricultural processes, the industrial processing and the transportation and waste management associated with olive oil production. Raw material and energy use as well as emissions were quantified on the basis of a functional unit of 1 l of extra virgin olive oil. The production of the inorganic fertilisers used in the agricultural stage of olive oil production and the disposal of liquid effluent from olive mills to evaporation ponds were found to be “hot-spot” processes not only in terms of resource consumption but also in terms of emissions into the environment.     

生命周期评价在工农业生产中的应用研究

生命周期评价是指产品在整个生命周期中对环境的影响、对物质和能源的投入、产出进行汇集、测定的系统方法。从产品生命周期评价的发展过程和技术框架入手,对生命周期评价的意义以及工农业生产中的应用进行探讨,着重阐述了生命周期评价在农业生产、环保工艺、节能减排、清洁生产和环境管理中的应用。并认为生命周期评价应广泛用于环境治理领域,这是解决社会生产发展和环境污染之间矛盾的主要手段。     

Diagnosis and proposals for waste management in industrial areas in the service sector: case study in the metropolitan area of Granada (Spain)

Industrial parks play a significant role in the production and use of goods and services. However, this also means that the environmental problems of each company are concentrated in a relatively small area. One of these problems is solid waste disposal, which has become a critical issue because of its negative impacts as well as the resources consumed. Integrated solid waste management integrates cleaner and more sustainable production strategies by reducing resource consumption and applying mechanisms found in natural ecosystems to industrial systems. Nevertheless, one of the necessary conditions for the design of such a system is a preliminary study of waste generation management in the area. The study presented in this paper characterizes industrial waste production and management in the metropolitan area of Granada (Spain), and analyzes its strengths, weaknesses, opportunities and threats. A similar typology of industrial activities, mainly in the distribution and transportation sector, as well as the proximity of various industrial parks could facilitate their partnership in environmental management. The results obtained in our study point to significant weaknesses in the system, such as the lack of effective waste management tools and training for waste management personnel. Other weaknesses were, the low percentage of selective waste collection and the existence of unauthorized collectors. The paper concludes with specific proposals for waste collection. These recommendations include the creation of the following: (i) a community responsible for waste management; (ii) recycling points in industrial parks; (iii) energy recovery from the waste; (iv) a market to sell, buy, and/or exchange waste; (v) one authorized set of waste management agents that would provide the advantages of an economy of scale.     

水泥窑协同处置工业废弃物的生命周期评价

以废白土、废催化剂和污染土壤等工业废弃物为研究对象,运用生命周期评价(LCA)方法,对水泥窑协同处置废弃物的环境影响进行评价.通过建立生产过程输入、输出清单,从全球变暖潜值、资源消耗潜值、人体毒性潜值等方面,基于Gabi5.0软件进行建模与计算,对水泥窑常规生产工艺与协同处置工业废弃物工艺产生的环境影响进行比较.结果表明:功能单位(1 t)水泥的生产过程中,常规生产工艺和协同处置工艺的环境影响潜值分别为5.78×10~(-11)和5.61×10~(-11),协同处置工艺使得全生命周期环境影响潜值降低了2.94%;水泥生产过程最主要的环境影响是全球变暖和人体毒性,其中,协同处置工艺下这两种环境影响分别降低了0.80%和1.80%,资源消耗相比常规生产降低了11.1%;从全生命周期看,水泥生产中熟料煅烧阶段对环境的影响最大,协同处置工艺下熟料煅烧阶段的环境影响相比常规生产降低了8.0%.协同处置工艺相比常规生产工艺有更好的环境效益.     

Environmental impacts of cocoa production and processing in Ghana: life cycle assessment approach

Ghana is the world's second largest producer of cocoa beans. In addition to exporting raw cocoa beans, the country also processes some of its beans into finished and semi-finished cocoa products for both the local and international markets. This paper is aimed at providing a comprehensive picture of the environmental impacts associated with cocoa production and processing in Ghana by applying the life cycle assessment (LCA) methodology. The analysis considered the entire system required to produce and process 1 kg of cocoa bean. It included the extraction of raw materials (e.g. fossil fuels, minerals), the production of farming inputs (e.g. fertilizers and pesticides) and all agricultural operations in the field (e.g. tillage, fertilizer and pesticides application, harvest, etc.). Transportation of beans to processing factory and industrial processing of the beans into cocoa butter, liquor, cake and powder were also included. The study was conducted in accordance with the international ISO procedural framework for performing LCA in the ISO 14040–14043 series.The overall environmental impacts resulting from cocoa production and processing activities and improvement options towards the sustainability of the system studied are presented and discussed.     

Resource use and waste management in Vietnam hotel industry

The hotel industry of Vietnam is expanding rapidly with increasing international arrivals and domestic tourists. At the same time, mounting costs of resources and impacts of waste could affect the income, environmental performance and public image of the hotel sector. The hotel industry’s resource management (energy and water) would contribute to the long-term sustainability of the tourism sector. This paper reports the results of a study conducted to assess the resource use and management in the hotel industry in Vietnam. This was obtained by carrying out a survey in 50 hotels on energy and water consumption, and waste generation. The energy and water use, as well as the waste generated in the various hotel categories have been estimated and compared with those in other countries. The current practices in the hotels to address these issues are highlighted, and benchmarks for efficient use of resources in Vietnamese hotels are presented.