中国城市居民生活能源碳排放的时空格局及影响因素分析

随着经济社会的发展与人民生活水平的提高,生活用能强度逐年增大,城市居民生活能源碳排放日益成为碳排放的新增长点.本文采用Theil指数、空间自相关分析了我国城市居民生活能源碳排放的时空格局演变特征,并利用STIRPAT模型分析了影响城市居民生活能源碳排放的主要因素.结果表明:12001—2012年我国城市居民生活能源碳排放总量及人均生活能源碳排放量均呈增长趋势,其年增长率分别为9.69%、3.29%;2八大经济区域间城市居民人均生活能源碳排放的差异是构成我国城市居民人均生活能源碳排放总体差异的主要原因,其对总差异的贡献率达到了57.90%;3我国城市居民人均生活能源碳排放具有显著的空间正相关性,2001—2012年间城市居民人均生活能源碳排放的"冷点"区变化较为稳定,主要分布在东部和南部经济区,而"热点"区主要分布在西北、东北和黄河中游经济区;4城市人口规模、城市居民可支配收入、城市居民生活消费支出、城市居民年龄结构均对城市居民生活能源碳排放量具有加剧作用,而城市居民能源消费结构具有减缓作用,且北方城市居民生活能源碳排放量明显高于南方;5现有样本数据支持环境Kuznets曲线假说,即随着经济的发展,城市居民生活能源碳排放量存在转折点.     

中国水泥碳排放测算的影响因素分析与不确定度计算

作为水泥生产大国和CO_2排放大户,中国水泥行业的CO_2排放在国际上受到越来越广泛的重视,然而不同的研究结果之间存在不同程度的差异.为了定量研究中国水泥碳排放测算的影响因素,对碳排放因子的测算、运营边界的界定及水泥熟料或水泥成品的产量这3个影响因素做了详细分析,并对碳排放因子的不确定度做了定量计算.结果发现,影响中国水泥碳排放测算的最主要因素是碳排放因子,而该因素又与生产工艺、燃料和熟料水泥比等密切相关.本研究结果比IPCC、EDGAR、CDIAC和WBCSD/CSI等研究结果均低,并且差异逐年显著,以水泥碳排放来自碳酸盐分解的部分为例,2000年相差约65 Mt,而2012年差值接近450 Mt.计算表明,中国水泥碳排放不确定度为12%~22%.因此,水泥碳排放测算的影响因素较多,在计算中国水泥碳排放量时不可照搬国外研究的参数.     

Bottom-up approach for downscaling CO2 emissions in Taiwan: robustness analysis and policy implications

The roles and responsibilities of cities in CO₂ mitigation have drawn increasing attention in recent years. To facilitate optimal design of effective mitigation policies, it is important for city authorities to understand the magnitudes and sources of their CO₂ emissions, and their relative shares of emissions at a higher spatial level. Although several studies estimate CO₂ emissions at the city level, the robustness of these estimates and their linkage to emissions at a higher level remains unclear. This kind of localized information on emissions is important for coordination of climate policies at different spatial scales. The study aims to fill a gap in understanding by building a systematic bottom-up approach for estimating urban CO₂ emissions and offering a consistency check with IPCC top–down estimates. Using Taiwan as a case study, we display the geographic distribution of CO₂ emissions. The significance and implications of the downscaling CO₂ emissions are indicated accordingly.     

不锈钢厂废水减排回用及提标工艺技术研究

国务院环保部近年来出台了多项环保政策和排放标准,根据最新的钢铁工业水污染物排放标准,某不锈钢厂首先对废酸水处理站排水进行生物脱氮预处理,然后与循环水站排污水混合后,采用混凝沉淀-砂滤-超滤-反渗透组合工艺进行减排回用处理,出水达到工业水标准后回用,对反渗透浓水采用生物脱氮-混凝沉淀-电催化氧化-砂滤工艺进行处理,处理后出水达到《钢铁工业水污染物排放标准》(GB 13456-2012)直接排放标准后外排.     

河口潮滩湿地CH4、CO2排放通量对氮硫负荷增强的响应

以闽江河口区高、中潮滩短叶茳芏湿地为研究对象,于2014年6—11月植物生长季进行氮硫负荷增强实验,利用静态箱-气象色谱法测定土壤CH_4、CO_2排放通量,并同步观测相关环境因子.结果表明,氮硫负荷增强对潮滩湿地CH_4、CO_2排放通量的影响不尽一致.与对照相比,NH_4~+-N输入使高、中潮滩CH4排放通量分别提高了(107.53%,7.19%),使高潮滩CO_2排放通量增加了3.39%,中潮滩减少了3.00%;NO_3~--N输入使高潮滩CH4、CO_2排放通量分别增加了(29.99%,16.99%),使中潮滩分别减少了(3.45%,4.77%);SO_4~(2-)-S输入使高、中潮滩CH4排放通量分别减少了(8.99%,7.67%),使高潮滩CO_2排放通量减少了3.87%,中潮滩增加了5.44%;N-S复合输入使高、中潮滩CH4排放通量分别提高了(72.48%,25.66%),CO_2排放通量提高了(13.32%,13.48%).氮硫负荷增强改变了短叶茳芏沼泽生长季CH_4、CO_2排放通量变化规律,但除了NH+4-N处理对高潮滩CH4通量的影响显著外,其他处理影响均未达到显著性水平.相关分析显示,高、中潮滩湿地CH_4、CO_2排放通量与土壤温度,含水率具有显著的正线性相关关系,与土壤电导率相关性不显著.在全球环境问题日益严重背景下,系统研究湿地生态系统温室气体排放的机制与规律,对于准确估算全球温室气体排放量具有重要而直接的意义.     

城镇化、居民生活能源消费与生活碳排放之间关系的实证研究

利用中国1995年－2012年居民生活能源消费数据,通过协整检验、格兰杰因果关系检验等方法对城镇化、居民生活能源消费与碳排放之间关系进行了实证研究,结果发现：城镇化、居民生活能源消费与碳排放存在长期均衡关系;城镇化程度的提高会降低CO2排放;生活能源消费的增加是CO2排放提高的重要原因。居民生活能源消费与CO2排放之间存在着双向格兰杰因果关系。提出稳步推进新型城镇化进程、合理进行生活能源消费、调控城乡居民生活能源消费等建议。     

Greenhouse gas emission reductions in the post-Kyoto period: Emission intensity changes required under the 'contraction and convergence' approach

Various approaches have been proposed for allocating commitments to countries regarding the mitigation of greenhouse gas emissions. One of these methods is the ‘contraction and convergence’ approach, which defines emission permits on the basis of converging per capita emissions under a contracting global emission profile. The approach is unique in its simplicity. Only two major issues need to be negotiated and agreed upon: the target atmospheric concentration of CO₂ and the date when the entitlements are to converge at equal per capita allocations. According to the contraction and convergence approach, developing countries can continue their current emission trends, whereas industrialized countries should reduce their emissions quite dramatically. This regime represents a shift away from the current approach towards defining commitments for all parties and their evolution over the long term. This article analyses how allocation schemes determined by the contraction and convergence approach might affect certain OECD and non‐OECD countries. Results for eleven countries selected for analysis (United States, United Kingdom, Germany, France, Japan, China, Venezuela, Thailand, Brazil, India and Indonesia) reveal that trends observed in the past few decades in most industrialized countries will lead to the contraction and convergence target.     

Processing National CO2 Inventory Emissions Data and their Total Uncertainty Estimates

The uncertainty of reported greenhouse gases emission inventories obtained by the aggregation of partial emissions from all sources and estimated to date for several countries is very high in comparison with the countries’ emissions limitation and reduction commitments under the Kyoto Protocol. Independent calculation of the estimates could confirm or question the undertainty estimates values obtained thus far. One of the aims of this paper is to propose statistical signal processing methods to enable calculation of the inventory variances. The annual reported emissions are used and temporal smoothness of the emissions curve is assumed. The methods considered are: a spline-function-smoothing procedure; a time-varying parameter model; and the geometric Brownian motion model. These are validated on historical observations of the CO₂ emissions from fossil fuel combustion. The estimates of variances obtained are in a similar range to those obtained from national inventories using TIER1 or TIER2. Additionally, some regularities in the observed curves were noticed.     

长三角城市居民家庭直接能耗碳排放空间特征及影响因素研究

目前关于碳排放的研究主要以国家和行政省(自治区、直辖市)为研究对象,围绕城市尺度家庭层面碳排放的研究相对匮乏,而家庭是社会最基本的组成单位,针对相关的碳排放特征及影响问题亟待解决.本文以2007—2016年长三角地区26个地级市数据为样本,测算城市居民家庭直接能耗碳排放量.利用K均值聚类法、空间相关性检验及空间面板建模等方法,考察城市居民家庭直接能耗碳排放量的空间演变分布特征及影响因素.结果表明:①城市居民家庭直接碳排放量高的城市位于长三角中部偏东的位置,排放量低的城市集中在西部位置,中部地区的碳排放量增长速度普遍快于其他地区.②长三角地区城市居民家庭直接能耗碳排放的空间关联程度呈"N"字形趋势,处于高高集聚状态的区域集中在以苏州市等为核心的偏中部地区,处于低低集聚状态的区域集中在西部边缘地区.③前后5年的回归结果对比表明:户均人口数由不显著的正向影响因素转变为重要的抑制因素;户均私家车与每户拥有的城市道路面积联合效应的正向影响作用越来越强烈.研究结论可为城市在动态制定碳减排政策时提供理论依据.     

Performance evaluation and emission characteristics of biodiesel-ignition enhancer blends propelled in a research diesel engine

This study details the effect of the Di-Methyl-Ether(DME) as a cetane improver on neat cashew nut shell biodiesel (CBD100) to assess the emission and performance engine characteristics. Four fuels, namely, diesel, biodiesel (Cashew nut shell Methyl Ester), a blend of CBD100-10% and 20% by volume of DME (CBD90DME10and CBD80DME20) are prepared and tested on a stationary research diesel engine. The experimental parameters for CBD80DME20 showed a 1.6% increase in thermal efficiency thereby reducing 4.1% of fuel consumption than the neat biodiesel at peak conditions. Experimental result exposed that 20% of DME reduces 3.4% CO, 4.2% HC and 8.8% NOx and 8.4% smoke emissions of CBD100. Based on the outcome of this work, it is clear that CBD80DME20 shall be employed as a substitute fuel for diesel engine.

Abbreviations: CI: Compression ignition; CBD100: Cashew nut shell Bio-diesel; DME: Di-methyl ether; CO: Carbon monoxide; BTE: Brake thermal efficiency; BSFC: Brake specific fuel consumption; CBD100: 100% Biodiesel; CBD90DME10: 90% biodiesel + 10% di-methyl-ether; CBD80DME20: 80% biodiesel + 20% di-methyl-ether; HC: Hydrocarbon; NO_x: Oxides of nitrogen.