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181.
中国能源消费与温室气体排放预测分析   总被引:4,自引:0,他引:4  
构造了中国18个部门的能源—经济—环境投入产出模型,分析了能源消耗系数的变动规律,对2020年我国能源消费量与温室气体排放量进行了预测。结果表明:我国2020年的能源消费总量为29.5亿t(标准煤),等于1990年的299%,1995年的229%;煤炭消费最为26亿t,石油消费量为4.1亿t,天然气消费量为1420亿m~3,水电6400亿kW·h;能源消费弹性系数为0.43左右;CO_2排放量为17.50亿t(碳当量)。  相似文献   
182.
热泵蒸馏应用于橡胶助剂废水预处理的研究   总被引:7,自引:0,他引:7  
橡胶助剂废水属于难处理的工业废水,尤其是CBS(N-环己基-2-苯并噻唑次磺酰胺,英文名N-cyclohexy1-2-benzoth-iazole sulfonamide,简称Accelerator CBS)生产废水的COD达40000mg/L,并且含有杂环类有害化合物,难降解,难生化。经过絮凝沉淀、化学氧化、电化学法、吸附法等实验方法,处理效果都不是十分理想。采用热泵蒸馏技术对橡胶促进剂CBS的废水进行预处理实验,可使CBS废水的COD从40000mg/L降至1600mg/L,结果表明,该技术设备简单,投资少,操作方便,运行成本低,并能达到较理想的预处理效果。  相似文献   
183.
植树造林已普遍作为减缓全球变暖的主要对策之一,其主导思想是利用森林的光合作用吸收大气中的CO_2。目前很少人注意到缓解全球变暖的另一种途径,即从森林生物量中获取替代矿物燃料的生物能源。  相似文献   
184.
Access to affordable and efficient energy is a basic human right and an imperative for human development. The energy policies usually ponder technical, economic, environmental, and social aspects for successful procurement of energy and endowment of energy resources. The objectives of this paper are to analyze energy policies in Pakistan and assess their relationship with environmental security and development. An empirical and multi-criteria decision analysis was used to unfold the strong interactions of energy security with development and environment. The energy policies in Pakistan are more equipped with economic and technical aspects, fairly framed with social aspects and poorly pampered with environmental facets. The dearth of environmental aspects will not only results in environmental degradation but also lag the development and achievement of Sustainable Development Goals.  相似文献   
185.
Hydrothermal carbonization (HTC) is a thermal conversion technique that converts food wastes and associated packaging materials to a valuable, energy-rich resource. Food waste collected from local restaurants was carbonized over time at different temperatures (225, 250 and 275 °C) and solids concentrations to determine how process conditions influence carbonization product properties and composition. Experiments were also conducted to determine the influence of packaging material on food waste carbonization. Results indicate the majority of initial carbon remains integrated within the solid-phase at the solids concentrations and reaction temperatures evaluated. Initial solids concentration influences carbon distribution because of increased compound solubilization, while changes in reaction temperature imparted little change on carbon distribution. The presence of packaging materials significantly influences the energy content of the recovered solids. As the proportion of packaging materials increase, the energy content of recovered solids decreases because of the low energetic retention associated with the packaging materials. HTC results in net positive energy balances at all conditions, except at a 5% (dry wt.) solids concentration. Carbonization of food waste and associated packaging materials also results in net positive balances, but energy needs for solids post-processing are significant. Advantages associated with carbonization are not fully realized when only evaluating process energetics. A more detailed life cycle assessment is needed for a more complete comparison of processes.  相似文献   
186.
张琳  王禹  姜林  孙金华 《火灾科学》2016,25(3):132-139
以122mm钢制药筒装药为研究对象,开展了不同热通量下钢制药筒装药烤燃实验及数值模拟研究。以石膏粉替代发射药,通过烤燃实验研究了122mm钢制药筒内置石膏粉在不同热通量下的温升曲线、温升过程中的最高温度点及其达到发射药热点火温度的时间,并与数值模拟结果对比,得到一定程度上符合较好的结果。通过对数值模拟模型及结果的合理性分析,对122mm钢制药筒内置9/7发射药在不同热通量下的烤燃情况进行了数值模拟,得到不同热通量下钢制药筒装药的燃爆点、燃爆温度及燃爆时间,并得到燃爆温度及燃爆时间与环境热通量的关系,以其为参考,对弹药的日常储运安全及消防安全具有一定的指导意义。  相似文献   
187.
Abstract

The method of exergy analysis is presented for a SOFC power plant involving external steam reforming and fed by methane and ethanol. The optimal operation parameters of the integrated SOFC plant are specified after minimizing the existing energy and exergy losses. A comparison of methane and ethanol as appropriate fuels for a SOFC-based power plant is provided in terms of exergetic efficiency assuming the minimum allowable (for carbon-free operation) reforming factors for both cases. Then, a parametric analysis provides guidelines for practical design. It is concluded that the exergy calculations pinpoint the losses accurately and that the exergy analysis gives a better insight into the system's process.  相似文献   
188.
Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate groundwater use through direct state control, groundwater markets, energy pricing, and user self-regulation. We present and analyze these regulatory mechanisms and their outcomes in the field. We argue that the close interdependencies of these regulatory mechanisms have pre-empted the effectiveness of these policy instruments as well as that of other measures aimed at reducing groundwater use in order to advance towards sustainable exploitation levels.  相似文献   
189.
In the wake of the Fukushima nuclear accident, alternative energy paths have been discussed for Japan, but except for a few studies the assumption is usually made that Japan is too densely populated to be suited for a near-100% sustainable, indigenous energy provision. The studies emphasizing renewable energy have proposed the use of photovoltaic power as the main source of electricity supply, in combination with diurnal battery storage and supplemented by other renewable sources such as wind, hydro, and geothermal power. Here, an alternative approach is explored, with wind and derived hydrogen production as the main energy source, but still using solar energy, biofuels, and hydropower in a resilient combination allowing full satisfaction of demands in all sectors of the economy, i.e., for dedicated electricity, transportation energy as well as heat for processes and comfort. Furthermore, the possible advantage of establishing a regional energy system with energy interchange and coordinated management of the mix of renewable energy resources across a wider region is discussed. As the closest neighbor, the energy system of South Korea is considered, first regarding the possibility of a similar full renewable energy reliance, and then for possible synergetic effects of connecting the Korean and the Japanese energy systems, in order to be able to better cope with the intermittency of renewable energy source flows.  相似文献   
190.
Hydrofluorocarbons (HFCs) are synthetically produced compounds primarily used for cooling purposes and with strong global warming properties. In this paper, we analyze the global abatement costs for achieving the substantial reductions in HFC consumption agreed in the Kigali Amendment (KA) of the Montreal Protocol from October 2016. We estimate that compliance with the KA is expected to remove 39 Pg CO2eq or 61% of global baseline HFC emissions over the entire period 2018–2050. The marginal cost of meeting the KA targets is expected to remain below 60 €/t CO2eq throughout the period in all world regions except for developed regions where legislation to control HFC emissions has already been in place since a few years. For the latter regions, the required HFC consumption reduction is expected to come at a marginal cost increasing steadily to between 90 and 118 €/t CO2eq in 2050. Depending on the expected rate of technological development and the extent to which envisaged electricity savings can be realized, compliance with KA is estimated attainable at a global cost ranging from a net cost-saving of 240 billion € to a net cost of 350 billion € over the entire period 2018 to 2050 and with future global electricity-savings estimated at between 0.2% and 0.7% of expected future electricity consumption.  相似文献   
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