黄土高原能源富集区水—能源—粮食纽带系统安全时空耦合协调关系分析——以榆阳区为例

黄土高原能源富集区是我国重要的能源基地和粮食主产区,其水资源匮乏使区域水—能源—粮食纽带系统可持续发展面临严峻挑战。为研究黄土高原能源富集区能源、粮食与水资源之间协调发展状况,本研究以水—能源—粮食纽带系统安全为核心,通过构建水—能源—粮食纽带系统安全评价指标体系,采用TOPSIS模型和耦合协调度模型,分析了典型案例地榆林市及榆阳区水—能源—粮食纽带系统安全水平及其耦合协调关联特征。结果表明：从水—能源—粮食纽带系统耦合协调关系来看,榆林市各区县水—能源—粮食纽带系统耦合度整体较高且近年来呈现缓慢下降趋势,耦合协调度呈现“北高南低”格局且近年来表现出轻微下降趋势。从榆阳区层面来看,榆阳区水—能源—粮食纽带系统耦合度较高,耦合协调度呈现由中度协调向优质协调发展态势,水资源系统制约水—能源—粮食纽带系统安全发展,能源子系统波动性较强。为协调能源富集区水—能源—粮食纽带系统可持续发展,政府应健全跨部门协调机制,因地制宜、合理规划产业布局,同时构建节约高效的资源管理体系,提升资源使用效率。     

重庆市废润滑油的污染状况及改善策略的研究

针对重庆市2005年3～9月的半年时间里,仅嘉陵江主城流域内即出现四起重大油污染事故的现象,开展了对重庆市各类废润滑油年均产生量及处理现状的跟踪调研,结果表明:重庆市废润滑油的不当处理,在造成约5.5万t/a宝贵资源大量浪费的同时,还形成了对长江水系的严重污染。为推动重庆市经济的可持续发展和有效的保护环境,对目前在废油处理中存在的问题,进行了深层次原因的分析,并提出解决这些问题的有效措施:完善废油回收处理机制及体系,统一建立一个年处理能力在10万t以上的废油专业再生厂,通过废油再生的产业化实现对资源的最大化利用和对环境污染的最小化。     

水葫芦厌氧发酵工程化应用研究

在实验室进行了接种率、破碎程度和温度等对水葫芦厌氧发酵产气率的影响研究.结果表明:水葫芦在中温35℃下,水葫芦和接种污泥的最佳接种率为1:1(总固体物质比),经简单切分后产气率最高,原料产气率为0.540 m3/d(以每千克固体含量计,下同);高温消化与中温消化相比,产气率无明显优势.在实验室研究基础上,对中国农村地区原有的沼气发酵工艺进行适当的改进,设计构建了5 m3 15 m3(酸化池 产气池)两级反应池,该反应池在夏季常温条件下运行良好,80 d的平均原料产气率达0.305 m3/d.     

生物质废弃物快速热解制取富氢气体的实验研究

采用管式炉对红松锯屑快速热解制取富氢气体进行了实验研究,分析了反应器温度、物料粒径和催化剂对热解产物组成的影响.结果表明高温能加快生物质快速热解进程,减少炭和焦油生成量,利于富氢气体的生成,800℃时气态产物比例可达56.9 wt.%,气态产物中H2体积分数由4.3%(500℃下)上升至17.2%,H2 CO体积分数达68.3%.小粒径能增大热解气态产物的比例,但对气态产物组成的影响很小,这可能与红松锯屑本身质地疏松有关.以与生物质直接混合方式添加的煅烧白云石能使热解产物中H2含量增加,但造成产气过程变缓,炭生成量增多,富氢气体总产量未能得到提高.     

蒽醌化合物的光解动力学及定量结构-性质关系

以高压汞灯为光源, 测定了15 种蒽醌化合物(ATQs)的光解速率常数(k), 讨论了取代基位置、数目及种类对ATQs 光解速率的影响.另外,选取9 种氨基蒽醌, 应用偏最小二乘(PLS)算法, 建立了关于k的定量结构-性质关系(QSPR)模型. 根据该模型, 决定k值大小的主要因素包括:分子生成热、H 原子所带最大正电荷、C 原子所带最大负电荷,以及分子最低未占据轨道与最高占据轨道能量差.     

CDM Project Activities in China＇s Iron and Steel Industry：Current Status,Barriers and Development Strategies

China is now facing huge pressure from both the domestic concern of energy security and the global community's call for emission reduction commitment. As one of the major energy consumers and greenhouse gas emitters, China's iron and steel industry has a huge clean development mechanism (CDM) potential. This article both quantitatively and qualitatively analyzes the current status of CDM project activities in the iron and steel industry in China, including characteristics of approved project types, applicable methodologies, and potential technology fields. From the perspective of project implementation, the article summarizes development barriers such as high investment risk, difficulty in project identification, strict requirements on PPDs, long registration waiting time, and etc. Policy suggestions are also put forwarded to help better promote the development of CDM projects in the iron and steel industry.     

中国水泥行业节能减排的潜力与成本分析

全球水泥的温室气体排放约占人类活动排放的5%,其中中国的水泥产量就占到世界总量的50%,连续25年居世界第一位,2010年中国水泥总产量达到18.8亿t。水泥行业是我国排放和耗能的大户,其产业特点是总体产量高,企业平均规模小、技术水平低和产品结构落后,因而,水泥行业节能减排行动是我国应对气候变化的重要措施和基本内容,也是实现我国水泥工业可持续发展的重要保证。本文通过大量的实地调研和数据收集,在识别了18种水泥行业节能减排的典型技术基础上,以日产5 000 t的生产线作为基准,通过边际减排成本的测算,定量分析了我国水泥行业节能减排技术的减排潜力和成本,并最终得到这些技术的边际减排成本曲线,按照减排成本由低到高的排序,主要的减排技术分为能源利用效率、替代能源、混合水泥和CCS技术。最后通过分析我国水泥行业节能减排的技术现状及相关的政策障碍,给出了相应的应对措施和政策建议。     

滇池流域水资源综合平衡管理研究

随着滇池治理的进展,在今后一个时期内,恢复滇池饮用水环境功能,成为滇池治理的首要目标和任务。围绕滇池流域水资源供求平衡,采用水资源全要素配置框架下的三次平衡分析理论,从整体上分析了滇池流域水资源供求平衡关系及存在的主要问题,提出了以需求为导向,建立滇池流域水资源综合平衡管理目标和措施。分析表明：在滇池治理的基础上,通过建立滇池流域水资源综合平衡管理体系,落实管理措施,从总量平衡的理论上能够充分发挥引水工程的作用,恢复滇池饮用水环境功能,实现水量、水质供求的综合平衡。建议进一步开展量化分析和模拟实验研究,为在滇池流域实施综合平衡管理提供可靠依据和建议     

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.     

Copper and Zinc in a paddy field and their potential ecological impacts affected by wastewater from a lead/zinc mine, P. R. China

As well known, at normal levels, copper and zinc are essential micronutrients for plants, animals, and humans. However, excessive Cu and Zn are toxic and disturb a wide range of biochemical and physiological processes. Using Atomic Absorption Spectrophotometer (AAS; Perkin-Elmer 3030, USA), soil and rice plant (Oryza sativa L.) samples collected from a paddy field in Lechang lead-zinc mine area, Guangdong Province, China were analyzed and their potential ecological impacts to local human and livestock were evaluated. The results showed that the paddy soils were contaminated with Cu and Zn. Both metals in soils had low bio-available fractions for paddy plants, animal and human by three chemically analytical techniques. Generally, were concentrations of copper and zinc root > straw > stalk > grain with hull > grain without hull (i.e. unpolished rice) and in the normal ranges indicating no ecological risk for local livestock and residents. All positive correlation coefficients, however, between heavy metals in rice plant and total, exchangeable (step 1 in Tessier's method established in 1979) and DTPA-extractable fractions in soils were found in this study indicating that elevated heavy metal in soils would increase long-term exposition and possible consequence of ecological hazard through food chains.