Environmental consequences of recycling aluminum old scrap in a global market

Nowadays, aluminum scrap is traded globally. This has increased the need to analyze the flows of aluminum scrap, as well as to determine the environmental consequences from aluminum recycling. The objective of this work is to determine the greenhouse gases (GHG) emissions of the old scrap collected and sorted for recycling, considering the market interactions. The study focused on Spain as a representative country for Europe. We integrate material flow analysis (MFA) with consequential life cycle assessment (CLCA) in order to determine the most likely destination for the old scrap and the most likely corresponding process affected. Based on this analysis, it is possible to project some scenarios and to quantify the GHG emissions (generated and avoided) associated with old scrap recycling within a global market. From the MFA results, we projected that the Spanish demand for aluminum products will be met mainly with an increase in primary aluminum imports, and the excess of old scrap not used in Spain will be exported in future years, mainly to Asia. Depending on the scenario and on the marginal source of primary aluminum considered, the GHG emission estimates varied between −18,140 kg of CO₂ eq. t⁻¹ and −8427 of CO₂ eq. t⁻¹ of old scrap collected. More GHG emissions are avoided with an increase in export flows, but the export of old scrap should be considered as the loss of a key resource, and in the long term, it will also affect the semifinished products industry. Mapping the flows of raw materials and waste, as well as quantifying the GHG impacts derived from recycling, has become an essential prerequisite to consistent development from a linear toward a circular economy (CE).     

Voluntary GHG reduction of industrial sectors in Taiwan

The present paper describes the voluntary greenhouse gas (GHG) reduction agreements of six different industrial sectors in Taiwan, as well as the fluorinated gases (F-gas) reduction agreement of the semiconductor and Liquid Crystal Display (LCD) industries. The operating mechanisms, GHG reduction methods, capital investment, and investment effectiveness are also discussed. A total of 182 plants participated in the voluntary energy saving and GHG reduction in six industrial sectors (iron and steel, petrochemical, cement, paper, synthetic fiber, and textile printing and dyeing), with 5.35 Mt reduction from 2004 to 2008, or 33% higher than the target goal (4.02 Mt). The reduction accounts for 1.6% annual emission or 7.8% during the 5-yr span. The petrochemical industry accounts for 49% of the reduction, followed by the cement sector (21%) and the iron and steel industry (13%). The total investment amounted to approximately USD 716 million, in which, the majority of the investment went to the modification of the manufacturing process (89%). The benefit was valued at around USD 472 million with an average payback period of 1.5 yr. Moreover, related energy saving was achieved through different approaches, e.g., via electricity (iron and steel), steam and oil consumption (petrochemical) and coal usage (cement). The cost for unit CO₂ reduction varies per industry, with the steel and iron industrial sector having the highest cost (USD 346 t⁻¹ CO₂) compared with the average cost of the six industrial sectors (USD 134 t⁻¹ CO₂). For the semiconductor and Thin-Film Transistor LCD industries, F-gas emissions were reduced from approximately 4.1 to about 1.7 Mt CO₂-eq, and from 2.2 to about 1.1 Mt CO₂-eq, respectively. Incentive mechanisms for participation in GHG reduction are also further discussed.     

家电企业的低碳发展与实践

为应对低碳与节能减排这一世界关注的问题,企业应当积极推行低碳战略,并确定实施战略的能力建设。通过对典型家电产品的生命周期分析及企业低碳体系试点的研究,得到了企业碳排放的基本数据,探索了家电产品在节能减排领域的发展潜力和方向。低碳领域的试点效果为企业带来了良好的环境效益和经济效益,结合中国的实际情况给出了低碳经济的四个后续关注点。     

Transaction costs and the clean development mechanism

The emissions trading provisions of the Kyoto Protocol and its clean development mechanism (CDM) are designed to permit greenhouse gas (GHG) emission reductions at the lowest cost globally. However, to ensure climate integrity, these reductions must pass through vigilant approval, monitoring and evaluation procedures that create additional transaction costs unrelated to the physical process of eliminating GHGs. Moreover, the CDM's additionality criterion creates constraints that magnify the influence of these transaction costs on project viability. If these costs are extreme, they could undermine the success of the CDM, and possibly of the Kyoto Protocol itself. This article describes the trading provisions of the treaty, creates a working definition of transaction costs, and discusses their effects. It then analyzes the process of creating a CDM project to identify the sources of transaction costs, illustrated by an example of a fuel substitution project in Ghana. The conditions for project profitability are analyzed and compared with recent GHG emission credit prices in Europe. The specific Ghanaian results are not generalizable to all CDM projects, but the model does suggest a template that can be used to analyze the effects of project and transaction costs in other contexts.     

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.     

Linking climate policy across economic sectors: A case for green growth in Nepal

While the energy sector is the largest global contributor to greenhouse gas (GHG) emissions, the agriculture, forestry, and other land use (AFOLU) sector account for up to 80% of GHG emissions in the least developed countries (LDCs). Despite this, the nationally determined contributions (NDCs) of LDCs, including Nepal, focus primarily on climate mitigation in the energy sector. This paper introduces green growth—a way to foster economic growth while ensuring access to resources and environmental services—as an approach to improving climate policy coherence across sectors. Using Nepal as a case country, this study models the anticipated changes in resource use and GHG emissions between 2015 and 2030, that would result from implementing climate mitigation actions in Nepal's NDC. The model uses four different scenarios. They link NDC and policies across economic sectors and offer policy insights regarding (1) energy losses that could cost up to 10% of gross domestic product (GDP) by 2030, (2) protection of forest resources by reducing the use of biomass fuels from 465 million gigajoules (GJ) in 2015 to 195 million GJ in 2030, and (3) a significant reduction in GHG emissions by 2030 relative to the business-as-usual (BAU) case by greater use of electricity from hydropower rather than biomass. These policy insights are significant for Nepal and other LDCs as they seek an energy transition towards using more renewable energy and electricity.     

中国典型城市固体废物可降解有机碳含量的测定与研究

城市固体废物填埋处理产生的甲烷是一种重要的温室气体,城市固体废物中可降解有机碳(DOC)含量是计算其甲烷排放量的重要因子之一.1996年IPCC指南给出了不同可降解有机碳的公式和不同类型固体废物可降解有机碳缺省值.该缺省值主要来自发达国家的文献,不能完全适合中国的实际情况.选择武汉和沈阳作为我国南方和北方城市的代表,分别在其老城区、新建城区、综合市场、食品超市、垃圾填埋场等区域进行固体废物采样,经过化学分析得到代表城市干基和湿基固体废物的含水率、含碳量和可降解有机碳含量,并对其成分特征进行分析,得到中国城市固体废物可降解有机碳含量推荐值.      

Tradable fuel economy credits: Competition and oligopoly

Corporate average fuel economy (CAFE) regulations specify minimum standards for fuel efficiency that vehicle manufacturers must meet independently. We design a system of tradeable fuel economy credits that allows trading across vehicle classes and manufacturers with and without considering market power in the credit market. We perform numerical simulations to measure the potential cost savings from moving from the current CAFE system to one with stricter standards, but that allows vehicle manufacturers various levels of increased flexibility. We find that the ability for each manufacturer to average credits between its cars and trucks provides a large percentage of the potential savings. As expected, the greatest savings come from the greatest flexibility in the credit system. Market power lowers the potential cost savings to the industry as a whole, but only modestly. Loss in efficiency from market power does not eliminate the gains from credit trading.     

Quantification of the regional carbon cycle of the biosphere: policy, science and land-use decisions

This paper addresses some issues related to the carbon cycle and its utilization by society. Traditional uses for agriculture, forestry, as a source of fuel and other products, and for pastoral farming, among others, have recently been supplemented by identifying its potential for mitigating the increasing concentration of greenhouse gases in the atmosphere. Through the Kyoto Protocol, carbon has become a commodity and the CO(2)-absorbing capability of the vegetation and soils an economically valuable asset. The multi-facetted roles of the C cycle and its sensitivity to human activities present a demand for techniques that permit accurate, timely and affordable characterization of the various components of this cycle, especially on land where most human activities take place. Such techniques must satisfy a range of demands in terms of purpose, clients for the information, and biosphere properties. However, if successful, they offer the potential to support monitoring, reporting, policy setting, and management of terrestrial biospheric resources. The context for these requirements and possibilities is illustrated with reference to the China Carbon Sequestration Project and its findings.     

石油天然气行业应对温室气体减排政策及措施

积极减排温室气体应对气候变化已经成为石油天然气行业的共识。文章介绍了2011年以来最新的国际和国内应对气候变化的政策环境,分析其对我国石油天然气行业的影响,特别强调国务院《"十二五"控制温室气体排放工作方案》对石油天然气行业的引导作用。在此基础上还提出积极参与行业碳减排政策研究、注重低碳经济发展规划、抓住低碳经济重点发展领域、积极呼应碳金融和碳交易的发展趋势、注重天然气应用技术开发、加强余热余压回收节能等发展低碳经济的建议。