页岩气开发对生态环境影响评价模型

针对页岩气特殊的开发方式及环评难度比常规气大的特点,运用"压力-状态-响应"框架模型,建立了页岩气开发对生态环境影响的评价指标体系。引入曲线投影的方式,并将投影寻踪方法和动态聚类方法相结合,提出了曲线投影寻踪动态聚类的定量评价方法;基于样本各指标的曲线投影和动态聚类方法寻找最佳投影方向,并建立相应的生态环境影响评价优化模型。结合全局最优经验指导和信息素交流,采用改进的蚁群算法对优化模型进行求解。该算法维持蚁群的多样性,且收敛性较好,同时也避免出现局部最优。对四川省威远页岩气区块进行了实例分析,结果表明:2010年、2011年和2014年的环评属于差类(4级),2012年和2013年的环评属于中类(3级),其中植被覆盖率、空气质量优良率、地表水质达标率、废水排放量、公众对环境的满意度、二氧化硫排放量和废水排放量达标率等指标对生态环境评价的影响较大。在页岩气开发初期,由于开发技术落后,再加上环保投资不高,环保意识不强,造成生态环境问题较为严重。随着学习借鉴美国的经验,及页岩气的开发技术进一步提高,加上国家对生态环境保护的重视,威远页岩气区块生态环境恶化得到有效的遏制。但开发时间越长,开采难度越大,将会产生更多更大的生态环境问题。分析结果与威远页岩气开发区域的实际情况相符,为页岩气气田生态环境影响评价奠定了科学基础。投影寻踪动态聚类方法具有无需设定参数、操作简单、客观等优点,是页岩气开发对生态环境影响评价的一种新方法。     

The impact of ISO 14001 on corporate environmental performance: a study of Swedish manufacturing firms

The debate concerning the environmental effectiveness of environmental management systems (EMS) based on ISO 14001 is still open and scholars have called for further studies that can explain the contrasting evidence in previous research. As a response, this study aims to contribute knowledge about the effects of ISO 14001-based EMS by presenting fact-based environmental data. The study focuses on changes in performance over a period of 12 years and includes both firms with an EMS (66 firms) and firms without one (50 firms). Consideration is given to the improvement efforts in the firms before EMS adoption making it possible to neutralize any selection effects where better environmental performance precedes ISO 14001 adoption. Analysis has been carried out using statistical methods for six different environmental areas. No statistically significant differences between certified and non-certified firms concerning the change in the rate of improvement could be found in any of the six areas. However, it can be suspected that EMS adoption has positive effects on energy use and waste production whereas the non-adopting firms seem to perform better concerning air emissions. These mixed results mirrors previous research, which is rather worrying considering the worldwide popularity of EMS based on ISO 14001 in industry.     

环境试验数据管理系统的应用

介绍了环境试验数据管理系统的功能及组成,阐述了系统建设的目的和达成的目标,并对其在企业内部的应用效果进行了分析。     

Comparative study on performances of a heat-pipe PV/T system and a heat-pipe solar water heating system

The heat-pipe solar water heating (HP-SWH) system and the heat-pipe photovoltaic/thermal (HP-PV/T) system are two practical solar systems, both of which use heat pipes to transfer heat. By selecting appropriate working fluid of the heat-pipes, these systems can be used in the cold region without being frozen. However, performances of these two solar systems are different because the HP-PV/T system can simultaneously provide electricity and heat, whereas the HP-SWH system provides heat only. In order to understand these two systems, this work presents a mathematical model for each system to study their one-day and annual performances. One-day simulation results showed that the HP-SWH system obtained more thermal energy and total energy than the HP-PV/T system while the HP-PV/T system achieved higher exergy efficiency than the HP-SWH system. Annual simulation results indicated that the HP-SWH system can heat the water to the available temperature (45°C) solely by solar energy for more than 121 days per year in typical climate regions of China, Hong Kong, Lhasa, and Beijing, while the HP-PV/T system can only work for not more than 102 days. The HP-PV/T system, however, can provide an additional electricity output of 73.019 kWh/m², 129.472 kWh/m², and 90.309 kWh/m² per unit collector area in the three regions, respectively.     

The determination and matching analysis of pinch point temperature difference in evaporator and condenser of organic rankine cycle for mixed working fluid

Exergo-economic analysis of the pinch point temperature difference (PPTD) in both evaporator and condenser of sub-critical organic Rankine cycle system (ORCs) are performed based on the first and second laws of thermodynamics. Taking mixture R13I1/R601a as a working fluid and the annual total cost per net output power Z as exergo-economic performance evaluation criterion, the effects of PPTD in evaporator ΔT_e, and the PPTD ratio of condenser to evaporator y, on the exergo-economic performance of ORCs are analyzed. Moreover, how some other parameters influence the optimal PPTD in evaporator ΔT_e,opt and the optimal PPTD ratio of condenser to evaporator y_opt are also discussed. It has been found that the exergo-economic performance of ORCs is remarkably influenced by ΔT_e and y, and there exists ΔT_e,opt and y_opt. In addition, ΔT_e,opt and y_opt are affected by heat transfer coefficient ratio of condenser to evaporator ß, the temperature of working fluid at dew point in condenser T_1a, and composition of R13I1/R601a: larger ß and T_1a lead to lower ΔT_e,opt and y_opt; by contraries, larger mass fraction of R13I1 makes ΔT_e,opt and y_opt increase, and y_opt increases linearly. The effects of the temperature of working fluid at bubble point in evaporator T_3a, mass flow rate of exhaust flue gas m_g, and inlet temperature of exhaust flue gas T_gi on ΔT_e,opt and y_opt are very slight. For comparison, three additional working fluids, namely R601a, R245fa, and 0.32R245fa/0.68R601a, are also taken into account.     

Two-echelon closed-loop supply chain deterministic inventory models in a batch production environment

This paper considers a two-echelon closed-loop supply chain consisting of a manufacturer and a remanufacturer at the upper echelon and a retailer at the lower echelon. The retailer faces a constant demand from customers, which is satisfied through recovered and new products received from the remanufacturer and the manufacturer, respectively. The manufacturer produces the product with finite rate, whereas the recovery of returned product is instantaneous at the remanufacturer. We develop three models to determine the optimal production-inventory policy of the players for minimizing the joint total cost of the system. In the first model, the retailer receives the product in batches from the manufacturer and the remanufacture simultaneously, whereas in the second and third models, the batches are received alternatively. In the third model, however, the procurement of raw material at the manufacturer is also considered. Numerical illustration is presented to examine the impact of certain key parameters.     

The key elements analysis of Guangdong & Shenzhen ETS & tips for China national ETS construction

The only joint effort area of provincial and municipal governments resides in Guangdong Province and Shenzhen City in China’s carbon emission trading system (ETS) pilots, which characterize the national carbon ETS plots. The present study on the operating experience from this area has important reference value for the national carbon ETS. Analysis and comparison of the key elements show many differences in coverage, total allowance, allowance allocation, and MRV mechanism between Guangdong and Shenzhen carbon ETS. The present study provides the following explanation: (1) the design characteristics of carbon ETS (e.g. coverage, total quotas, the allocation, and MRV mechanism) depend on the local geographical conditions and policy goals. The differences of economic structure in Guangdong Province and Shenzhen City result in different coverage, which then result in differences in other management elements. (2) The operating state of the carbon market is affected by overall design of carbon ETS: in the case of tighter total allowance, lower proportion of China Certified Emission Reductions, and harsher punishment, the carbon market is relatively active, which intends to produce carbon financial market. Based on deep analysis of operation characteristics of carbon ETS in Guangdong and Shenzhen, the present study suggests that (1) the allowance should be allocated freely at the beginning stage and then gradually transited to the voluntary paid auction; (2) the allowances assigned to companies shall be linked up with their energy-saving objectives; (3) the output fluctuations and economic influence on the allowance allocation should be properly handled to maintain the fairness and consistence of allowance allocation standards; (4) stable public expectation is one of the key elements to maintain the regular operation of carbon ETS; (5) constrained carbon emission behavior outside ETS can contribute to social justice; and (6) the improvement of professional skills of relevant personnel in the enterprise and independent third party can enhance carbon emissions data reliability.     

土地利用生态服务价值指标体系评估结果比较研究

生态系统服务价值评估越来越受到学术界关注。针对当前生态服务价值评估方法、指标体系和评估效果较多的实践,通过文献归纳,对国内外土地利用生态服务价值评价方法、指标体系及其系数进行了梳理、分类和评价,将指标体系分为Costanza和谢高地两大类,并将谢高地指标体系分为价值当量、价值系数和区域修正。以辽宁省2005、2010年土地利用数据为案例,运用Costanza价值系数、谢高地两个版本价值当量、两个版本价值系数的区域修正,分别核算了案例区生态系统服务价值及变化,并比较评价结果。研究得出Costanza价值系数应用于中国实践时评估结果显得偏低,谢高地2002版的价值当量和2002版的价值系数区域修正结果最接近平均值,相对较为可取,2007版的价值系数区域修正评估结果也较为接近均值但略低,2007版的价值当量评估结果总体偏高。研究结果有利于指导土地利用生态服务价值评估指标体系选取。     

The role of satellite and decentralized strategies in water resources management

Existing and projected water shortages and related factors have helped focus attention on the need for water reuse. With recent technological advances in wastewater treatment, it is now possible to produce reclaimed water of any quality. Thus, the use of reclaimed water will depend on the reuse opportunities and the cost of the required infrastructure. Historically, centralized wastewater treatment facilities have served the needs of organized societies since the mid 1800s. However, as there are limited options for expansion of most existing centralized facilities, the use of satellite and decentralized wastewater management systems offers significant advantages including being close both to the source of wastewater generation and to potential water reuse applications. The comparative advantages of satellite and decentralized wastewater management systems for a number of water reuse applications are presented and discussed in this paper. Selected case studies are presented to demonstrate the utility of satellite and decentralized wastewater management. Specific issues associated with the application of such systems in existing and in new developments are examined and discussed.     

Landfill site selection using spatial information technologies and AHP: A case study in Beijing,China

Site selection is an important and necessary issue for waste management in fast-growing regions. Because of the complexity of waste management systems, the selection of the appropriate solid waste landfill site requires consideration of multiple alternative solutions and evaluation criteria. Based on actual conditions of the study area, we considered economic factors, calculated criteria weights using the analytical hierarchy process (AHP), and built a hierarchy model for solving the solid waste landfill site-selection problem in Beijing, China. A geographic information system (GIS) was used to manipulate and present spatial data. All maps are graded from 1 (lowest suitability) to 5 (highest suitability) using spatial information technologies. The candidate sites were determined by aggregation based on the criteria weights. The candidate sites are divided by ‘best’, ‘good’ and ‘unsuitable’ landfill areas. Best landfill areas represent optimal sites; good landfill areas can be used as back-up candidate sites. Our work offers a siting methodology and provides essential support for decision-makers in the assessment of waste management problems in Beijing and other rapidly developing cities in developing countries.