海藻类生物质减排CO2的分析

CO2减排已经成为全球热点问题,而生物CO2固定技术被认为是符合自然界循环和节省能源的理想方式。海藻作为一种不占用耕地的生物质,其种类繁多,生长周期短,相比陆上生物质能真正实现短时期内的CO2零排放。通过对海藻类生物质一年周期生物固碳的计算,看出其减排CO2的潜力巨大,进而可考虑海藻培养与CO2排放行业实现共建,为我们提供CO2减排一种新思路。     

关于固体替代燃料燃烧CO2排放量的测算

本文通过对固体替代燃料的定义、标准、性质、指标的研究,用类比的方式得出其燃烧CO₂排放量的测算公式,再以某项目的样品为实例,通过样品间的横向对比,不同种类燃料间的纵向对比,研究固体替代燃料燃烧CO₂排放问题,可为今后企业制定减碳方案提供与借鉴。     

集成小型堆和可再生能源的超临界CO2循环发电系统

  [目的]  小型模块化压水堆(小型堆)核电站由于温度参数低,其发电效率不到30%,为了提高小型堆的核能利用效率,可将小型堆与可再生能源组合,并以先进的超临界CO₂循环作为热能转换为电能的装置。  [方法]  基于简单回热模式的超临界CO₂循环,并在此基础上增加一次间冷和一次再热,将小型堆与太阳能、生物质能热源集成为新型混合发电系统,对其发电效率进行了分析。  [结果]  结果表明:对于高压透平入口温度390 ℃的系统,发电效率34.13%,对于高压透平入口温度550 ℃的系统,发电效率41.22%。此外,对系统的安全性分析表明:CO₂本身是具备核安全属性的工质,并且超临界CO₂循环还可以作为反应堆的非能动余热排出系统,确保在严重事故工况下,反应堆持续排出衰变热。  [结论]  集成小型堆和可再生能源的超临界CO₂循环发电系统具备良好的发电效率和核安全性。     

基于碳捕集与液态CO2储能的综合能源系统优化调度

针对综合能源系统在新能源消纳方面的不足,提出一种基于碳捕集与液态CO₂储能的综合能源系统。首先,分析了液态CO₂储能实际运行特点以及碳捕集装置综合灵活运行方式的“削峰填谷”特性;其次,建立考虑液态CO₂储能与碳捕集装置不同运行方式的综合能源系统;最后,以系统总运行成本最小为目标函数建立优化调度模型,并通过负荷率、能源利用率等评价指标衡量调度结果。算例分析表明,该优化模型可提高能源利用率,缓解系统调峰压力,实现系统运行的经济性和低碳性。     

O2/CO2气氛下石灰石脱硫特性的研究

在沉降炉中进行了石灰石的脱硫特性研究.表明用20%O2+80%CO2的混合气体作助燃气时比用空气作助燃气时有较好的脱硫效果,并能减少NOx的排放,是一种新的能同时控制CO2,SO2和NOx三种污染物的好方法.图8参8     

高值化CO2利用现状及减碳效果分析

通过资源利用化的方式将CO₂转化为具有工业利用价值的产品,是实现碳中和目标的主要方式之一,结合上海“双碳”工作前景以及节能减排目标的实施,基于燃煤电厂CO₂捕集、利用商业模式和推广政策研究,通过对CO₂材料利用的现状进行评述,分析项目的经济效益和减碳效果,对高值化CO₂利用项目提供策略建议,有利于实现燃煤火电厂CO₂的减排和资源化利用,为上海碳中和专项工作提供支撑。     

江西省CO2排放现状及减排对策分析

2010年,国家首次把单位GDP CO2排放下降17%作为约束性目标纳入"十二五"国民经济与社会发展规划,并提出合理控制能源消费总量的设想,这预示着未来国家在节能和减缓碳排放方面,将采取力度更大的措施。江西目前正处在工业化和城市化加快发展的关键时期,"十二五"社会经济发展对能源需求将保持在一个较高的水平,这必然导致CO2排放量持续增加,从而使碳减排工作面临巨大挑战。因此,深入探讨CO2排放发展趋势特征及影响变化的重要因素,对于制定我省各种能源政策、抑制CO2排放量、控制CO2排放强度具有十分重要的现实意义。     

O2/CO2/H2O气氛下CO燃烧机理的分子动力学模拟研究

采用反应分子动力学(ReaxFF MD)模拟方法研究了O₂/CO₂/H₂O气氛下CO的燃烧。结果表明：根据化学平衡原理,高浓度CO₂抑制CO的氧化,同时CO₂在高温下参与反应CO₂+H—→CO+OH,进一步抑制CO氧化。在较低温度条件下,较高浓度H₂O的三体效应显著,抑制了CO氧化。另一方面,在较高温度条件下,H₂O参与的H₂O+H—→H₂+OH和H₂O+O—→OH+OH反应占据其化学作用的主导地位,进而促进CO氧化。随着O₂浓度的增加,CO的氧化速度加快。     

O2/CO2气氛下生物质混煤燃烧SO2排放特性的实验研究

在水平管式炉上通过在线烟气分析仪研究了O2/CO2气氛下生物质混合比例、温度、燃烧气氛及氧浓度对生物质混煤SO2排放特性的影响规律。结果表明,O2/CO2气氛下,随着生物质混合比例的增大,生物质混煤SO2释放峰值减小,SO2排放完毕的时间减少,SO2的排放量降低;随着温度的升高,生物质混煤SO2的排放量增加。O2/CO2和O2/N2气氛下随着氧浓度的增大,生物质混煤SO2的排放量均增加。相同氧浓度时,O2/CO2气氛下生物质混煤SO2的排放量略小于O2/N2气氛下的情况,其降低幅度约为5%左右。     

神华煤粉在CO2和N2高温气氛下SOx生成释放规律的研究

通过在固定反应床实验系统上,进行了不同燃烧气氛、不同氧气体积浓度、不同燃烧环境温度及不同颗粒粒径下神华煤粉的燃烧实验,在实验过程中对气体污染物SOx生成释放规律进行了研究。发现了CO2气氛下SOx呈现双峰现象,即在煤粉燃烧过程中,S元素转化成SOx的过程分为挥发分释放阶段和焦炭燃烧阶段。SOx释放过程中第一个峰的积分值占总积分值的百分比随着燃烧环境温度的升高而降低,即在较高的燃烧环境温度下SOx主要来源于无机硫化合物。在煤粉燃烧过程中,SOx生成释放曲线的2个峰值随着氧气浓度的升高而增加,SOx总生成量也略为增加;单位氧气消耗量生成的SOx(记为YSOx)随着燃烧环境温度的升高而升高;煤粉颗粒粒径对YSOx的影响规律不明显。高温1 600℃下,煤粉自固硫特性的作用下SOx的生成量与1 000℃时相当。     

中国农村生物质能消费的CO_2排放量估算

借助国际通用的CO2排放鼍计算方法,利用1996～2006年中国农村可再生能源统计资料,对中同农村生物质能消费的CO2排放情况及其空间分布进行分析探讨.结果表明,中国农村生物质能消费的CO2排放总量达到7.25×108t,约占农村生活能源消费CO22排放量的65%,占全国温窜气体总排放量的11.2%,其中秸秆、薪柴等传统生物质能利用方式贡献较大,可达98.64%～99.74%;中国农村生物质能消费CO2排放量的空间分布不均,四川、广西等省CO2排放量大,属超重排放区域,北京、天津、上海、西藏、青海等省(市、区)排放量小,属轻排放区域:区域生物质资源条件和经济社会水平是影响农村生物质能消费CO22排放的主要因素.     

Scenario analysis of bioenergy resources and CO2 emissions with a global land use and energy model

The purpose of the present study is to evaluate bioenergy supply potentials, land use changes, and CO₂ emissions in the world, using a global land use and energy model (GLUE) including land use competitions and overall biomass flows. Through a set of simulations, the following results were obtained: (1) Supply potentials of energy crops produced from surplus arable lands will be strongly affected by food supply and demand parameters in the future, such as animal food demand per capita. (2) The policy option, i.e. the world, large-scale introduction of modern fuelwood by felling and planting in existing forest, will cause drastic reduction of the mature forest area but will cause little reduction of the accumulated CO₂ emissions coming from both energy and forest sectors. One reason for this is that the additional CO₂ emissions owing to the land use conversion from the mature forest to the growing forest will partly cancel out the CO₂ reduction owing to the fuel substitution from fossil fuels to fuelwood. (3) When energy recovery of paper scrap is given priority to material recycling, bioenergy will substitute partly for fossil fuels; however the decrease in recycled paper scrap will cause an increase in roundwood felling demand. Hence, the results will be similar to those of (2).     

A decomposition analysis of CO2 emissions from energy use: Turkish case

Environmental problems, especially “climate change” due to significant increase in anthropogenic greenhouse gases, have been on the agenda since 1980s. Among the greenhouse gases, carbon dioxide (CO₂) is the most important one and is responsible for more than 60% of the greenhouse effect. The objective of this study is to identify the factors that contribute to changes in CO₂ emissions for the Turkish economy by utilizing Log Mean Divisia Index (LMDI) method developed by Ang (2005) [Ang, B.W., 2005. The LMDI approach to decomposition analysis: a practical guide. Energy Policy 33, 867–871]. Turkish economy is divided into three aggregated sectors, namely agriculture, industry and services, and energy sources used by these sectors are aggregated into four groups: solid fuels, petroleum, natural gas and electricity. This study covers the period 1970–2006, which enables us to investigate the effects of different macroeconomic policies on carbon dioxide emissions through changes in shares of industries and use of different energy sources. Our analysis shows that the main component that determines the changes in CO₂ emissions of the Turkish economy is the economic activity. Even though important changes in the structure of the economy during 1970–2006 period are observed, structure effect is not a significant factor in changes in CO₂ emissions, however intensity effect is.     

The impact of CHP generation on CO2 emissions

The combined generation of heat and power (cogeneration) is praised by many as a technique for reducing the emissions of CO₂ in industrialized nations. This is generally true but not always. In this article we discuss the impact of some major variables on the CO₂ emission reduction capacity of cogeneration. Two sets of variables are predominant: the characteristics of the CHP process and the composition of the electricity generation sector. We highlight the interaction between the two sets of variables with the help of diagrams.     

Energy demand and CO2 emissions reduction options in Nigeria

This paper presents policy options for reducing CO₂ emissions in Nigeria. The policies were formulated based on a thorough analysis of Nigeria's current energy consumption patterns and the projected evolution of key parameters that drive Nigeria's energy demand — primarily the rate of industrialization, the demand for transportation services, and the expansion of Nigeria's population. The study shows that the most promising options for reducing CO₂ emissions in Nigeria are improving energy efficiency and increasing the use of natural gas and renewable energy sources.     

Industrial CO2 emissions from energy use in Korea: A structural decomposition analysis

This paper attempts to quantify energy consumption and CO₂ emissions in the industrial sectors of Korea. The sources of the changes in CO₂ emissions for the years 1990–2003 are investigated, in terms of a total of eight factors, through input–output structural decomposition analysis: changes in emission coefficient (caused by shifts in energy intensity and carbon intensity); changes in economic growth; and structural changes (in terms of shifts in domestic final demand, exports, imports of final and intermediate goods, and production technology). The results show that the rate of growth of industrial CO₂ emissions has drastically decreased since the 1998 financial crisis in Korea. The effect on emission reductions due to changes in energy intensity and domestic final demand surged in the second period (1995–2000), while the impact of exports steeply rose in the third period (2000–2003). Of all the individual factors, economic growth accounted for the largest increase in CO₂ emissions. The results of this analysis can be used to infer the potential for emission-reduction in Korea.     

The role of energy efficiency in reducing Scottish and UK CO2 emissions

In 2003, the UK government launched its long-anticipated White Paper on energy, the centrepieces of which were ambitious targets for the production of electricity from renewable technologies and the long-term aspiration of a 60% reduction in UK greenhouse gas emissions by 2050. In the White Paper it was recognised that such a dramatic reduction in emissions will require significant changes in the way in which energy is produced and used. However there has been a general failure to recognise the fact that in order to meet emissions targets, the UK will have to significantly reduce its energy consumption; this is not helped by the general misconception in the UK that reductions in CO₂ emissions will occur simply by increasing the production of electricity from renewable sources.

Specifically, this paper highlights the current trends in renewables deployment and energy demand, with a specific focus on Scotland, where the authorities have set more ambitious renewables targets than the rest of the UK. As will be demonstrated in this paper, without energy demand reduction, the deployment of renewables alone will not be sufficient to curtail growth in UK CO₂ emissions. This is illustrated using a case study of the Scottish housing sector; whilst this case study is necessarily local in scope, the results have global relevance. The paper will also address the magnitude of energy savings required to bring about a reduction in emissions and assesses the status of the policies and technologies that could help bring such reductions about.     

Energy and CO2 emissions in Korea: Long-term scenarios and related policies

Korea will require increasingly higher energy inputs in coming years to further its economic development process. While due to the inconvenience of coal use and its negative impacts on the environment, Korea's reliance on its most carbon-intensive energy source will drop over the next few decades, the overall growth of energy demand (and particularly the rising consumption of oil) will translate into substantially higher emissions of energy-related CO₂. This paper presents the results of two long-term scenarios for Korea for the year 2025 in order to investigate the possibilities of constraining the future growth of energy and emissions. The results indicate that by improving energy efficiency through technological progress, fuel switching and related policies, Korea can begin to make the necessary transition to a less carbon-intensive future.     

CO2 emissions embodied in international trade: evidence for Spain

The objective of this paper is to analyse the sectoral impacts that Spanish international trade relations have on present levels of atmospheric pollution using an input–output model. We try to evaluate the exports and imports of the Spanish economy in terms of the direct and indirect CO₂ emissions (CO₂ embodied) generated in Spain and abroad. The results show a slightly exporting behaviour in the Spanish economy which, nevertheless, hides important pollution interchanges. Moreover, the sectors transport material, mining and energy, non-metallic industries, chemical and metals are the most relevant CO₂ exporters and other services, construction, transport material and food the biggest CO₂ importers, and those whose final demands also embody more than 70% of the CO₂ emissions.     

Driving forces of residential CO2 emissions in urban and rural China: An index decomposition analysis

There exist many differences between urban and rural China among which residential CO₂ emissions arising from energy consumption is a major one. In this paper, we estimate and compare the energy related CO₂ emissions from urban and rural residential energy consumption from 1991 to 2004. The logarithmic mean Divisia index decomposition analysis is then applied to investigate the factors that may affect the changes of the CO₂ emissions. It is found that energy intensity and the income effects, respectively, contributed most to the decline and the increase of residential CO₂ emissions for both urban and rural China. In urban China, the population effect was found to contribute to the increase of residential CO₂ emissions with a rising tendency. However, in rural China, the population effect for residential CO₂ emissions kept decreasing since 1998.