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141.
环境规制对技术效率和生产力损失的影响分析 总被引:7,自引:1,他引:6
以中国工业为研究对象,以经济发展程度不同所分的东部、中部和西部地区兰个地区作为研究区域,采用非参数数据包络法(DEA)中的径自效率测量方法(radial efficiency measure)为主要研究方法,分析了在1998-2005年期间环境规制对中国工业的技术效率和生产力损失的影响.研究结果表明,在指定的研究期间,环境规制使得中国工业技术效率提高,但是对于生产力的发展却产生了负面的影响.三个地区之间受环境规制影响的差异较大,其中东部为环境规制所付出的成本最大,即东部为环境污染所付出的环境成本最高,这也是为何从九十年代开始,污染物从东部往中西部转移的原因;从受污染物影响的角度来看,因控制废水而引起的生产力损失大于因控制SO2而引起的生产力损失,即对于中国工业,废水的环境成本大于SO2的环境成本.另外,从研究结果中也可知,在中国现有的生产方式下,实施严格的环境规制有一定难度,所以改变旧的生产方式,实施可持续发展的生产方式是当务之急. 相似文献
142.
Wang Junsong He Canfei 《中国人口.资源与环境(英文版)》2009,7(2):44-49
China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity. 相似文献
143.
反渗透处理稀土氨氮废水试验研究 总被引:4,自引:2,他引:2
根据稀土冶炼厂排放的碳铵沉淀洗涤废水的水质情况,采用NH4Cl和 NaCl模拟废水进行了反渗透可行性对比实验。模拟实验发现,在相同条件下反渗透对NaCl 较NH4Cl 有着更高的去除率,而NH4Cl 相对NaCl则有着更高的产水速率。实际废水试验结果表明,在恒定操作压力范围内回收率为65%的条件下,NH4Cl浓度为2.85 g/L的碳铵沉淀洗涤废水经反渗透处理其NH4Cl去除率为77.3%,可作为氨氮废水的预处理。对该废水处理成本进行了分析,得出其约为2.7元/m3,比相近浓度氨氮废水的氨吹脱处理成本节省约26%。 相似文献
144.
Forest ecosystems may be actively managed toward heterogeneous stand structures to provide both economic (e.g., wood production
and carbon credits) and environmental benefits (e.g., invasive pest resistance). In order to facilitate wider adoption of
possibly more sustainable forest stand structures, defining growth expectations among alternative management scenarios is
crucial. To estimate the effect of tree size and spatial distributions on growth for forest structures commonly considered
in uneven-aged forest stand management, large (0.2 ha+) plots were established in 14 uneven-aged ponderosa pine stands in
eastern Montana. All study trees were stem-mapped and measured for diameter and 10-year sapwood and basal area increment.
A generalized growth model was developed to predict both total and merchantable 10-year basal area increment for nine hypothetical
stand structures [three diameter distributions (reverse-J, irregular, flat) × three spatial distributions (clumpy, partial
clumpy, uniform)]. Results indicate that the size and spatial distributions of individual trees have a considerable effect
on overall stand growth. The greatest total stand growth was in stands with reverse “J” shaped tree size distributions, while
the greatest merchantable stand growth was in stands with “flat” diameter distributions and uniform spatial distributions.
Through better comprehension of generalized uneven-aged stand growth dynamics, forest managers may better assess the effects
of alternative stand structures on stand growth while providing forest stand structures that may be more resilient in a changing
climate. 相似文献
145.
介绍了XZKP型高效空塔喷淋烟气脱硫装置的技术原理、技术特点、中试及工业化试验的情况。该技术通过改进工艺和结构,在提高脱硫效率和脱硫剂循环利用率两项技术上成效显著,用户可在不增加装置投资的前提下,获得更高的效率和更低的运行成本。 相似文献
146.
Qing Zhou Christine W. Chan Paitoon Tontiwachiwuthikul Raphael Idem Don Gelowitz 《International Journal of Greenhouse Gas Control》2009,3(5):535-544
Post combustion carbon dioxide (CO2) capture is one of the most commonly adopted technologies for reducing industrial CO2 emissions, which is now an important goal given the widespread concern over global warming. Research on amine-based CO2 capture has mainly focused on improving effectiveness and efficiency of the CO2 capture process. Our research work focuses on studying the relationships among the significant parameters influencing CO2 production because an enhanced understanding of the intricate relationships among the parameters involved in the process is critical for improving efficiency of the CO2 capture process. This paper presents a statistical study that explores the relationships among parameters involved in the amine-based post combustion CO2 capture process at the International Centre for CO2 Capture (ITC) located in Regina, Saskatchewan of Canada. A multiple regression technique has been applied for analysis of data collected at the CO2 capture pilot plant at ITC. The parameters have been carefully selected to avoid issues of multicollinearity, and four mathematical models among the key parameters identified have been developed. The models have been tested, and accuracy of the models is found to be satisfactory. The models developed in this study describe part of the CO2 capture process and can help to predict performance of the CO2 capture process at ITC under different conditions. Some results from a preliminary validation process will also be presented. 相似文献
147.
影响脱硫系统运行经济性的因素及改进措施 总被引:2,自引:1,他引:1
分析了原烟气成分、脱硫剂石灰石等对脱硫系统运行经济性的影响,探讨循环泵组合投运和工艺参数控制对运行经济性的影响规律,提出改进湿法脱硫系统运行经济性的措施,为脱硫装置的节能、经济运行提供参考。 相似文献
148.
旨在对同站台换乘站的客流行为和规律,以及对车站乘客疏散时的情况进行分析和研究。通过建立同站台换乘站的微观疏散仿真模型,利用微观仿真软件VISSIM对某即将建成使用的同站台换乘站的仿真模拟,直观地对客流的疏散过程和疏散人群分布状况进行动态观察,通过改变模型的参数设置,考察不同情况下换乘站的换乘效率,得出提高换乘效率的措施和建议,并最终为换乘站的设施设计和运营管理提供辅助设计与决策支持。 相似文献
149.
Stef Proost 《Integrated Assessment》2000,1(2):145-156
This paper surveys some recent studies on conventional air pollution and climate change in the transport sector in Europe.
Fuel efficiency standards, car emission standards and transport pricing instruments are analysed from an economic perspective
taking into account environmental and economic efficiency objectives.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
150.
Heavy metals in untreated/treated urban effluent and sludge from a biological wastewater treatment plant 总被引:1,自引:0,他引:1
Oliveira Ada S Bocio A Trevilato TM Takayanagui AM Domingo JL Segura-Muñoz SI 《Environmental science and pollution research international》2007,14(7):483-489