600MW机组脱硫GGH技改措施及节能优化

针对山西阳城电厂2×600 MW机组脱硫系统烟气换热器（简称GGH）在运行中频繁堵塞、差压大、增压风机运行电流偏大、影响机组带负荷及脱硫系统安全稳定性下降等问题进行了分析,提出了GGH改造方案及运行优化措施,确保了机组及脱硫系统的安全、稳定运行.     

The SEAP in the city of Girona,a crossroads between boldness and pragmatism

The Covenant of Mayors has secured the commitments of over 5400 European Cities (as of December 2013) to achieving the European Union 20-20-20 climate change mitigation targets by 2020 through action at the local level. Due to the youth of the initiative, few experiences have been reported in the academic literature. We study the development of the Sustainable Energy Action Plan (SEAP) in the city of Girona (Catalonia, Spain) to analyse the opportunities and challenges this process may present in a small- to medium-sized, compact Mediterranean city. This knowledge can provide information to local authorities in similar municipalities, technical teams and decision-makers at the European level interested in enhancing the performance of such plans in the future. In this article, we explain how the SEAP was developed in Girona, the main results and proposed actions, and discuss the main setbacks. We conclude that an overarching European oversight organism is advisable to coordinate and aid local efforts.     

Toward a CO2 zero emissions energy system in the Middle East region

Climate change and energy security are global challenges requiring concerted attention and action by all of the world’s countries. Under these conditions, energy supplier and exporter countries in the Middle East region are experiencing further challenges, such as increasing domestic energy demand while energy exports have to concurrently be kept at high levels. Middle East countries process the largest proven oil and gas reserves in the world and contribute a large fraction of the world’s CO₂ emissions from the use of these as fuels both domestically and internationally. This paper addresses different policies that could dramatically change the future course of the Middle East region toward a zero CO₂ emission energy system. To this aim, an integrated energy supply–demand model has been developed to analyze required commitments including renewable energy and energy efficiency targets and the potential of nuclear power, all of which should need to be considered in order to reduce CO₂ emissions by 2100. The results indicate that nearly 43% of the global energy of the Middle East region can be supplied from non-fossil fuel resources in 2100.     

Effects of investment on energy intensity: evidence from China

This article explores the effects of investment upon energy intensity by applying a unique panel data of China’s 27 provinces between 2004 and 2013. In addition, it also particularly studies other factors, such as energy price, economic structure, and urbanization. The results, based on four econometric regression model results, suggest that in general, the indigenous investment on research and development is a more powerful tool to decrease China’s energy intensity regardless of region disparity. The foreign direct investment (FDI) has a prominent but not persistent effect on energy intensity. However, the outward direct investment has not shown its significant impact on energy intensity. At the level of an aggregate economy and China’s eastern region, the results demonstrate that FDI improves energy efficiency significantly. For the central and western provinces, FDI does not support the similar conclusion. Based on these analyses, we present the corresponding regional policies for policymakers.     

MTBE in California's Drinking Water: A Comparison of Groundwater Versus Surface Water Sources

During the last decade, the fuel oxygenate methyl tertiary butyl ether (MTBE) has received widespread attention as a potential threat to water quality, primarily due to leaking underground gasoline storage tanks and watercraft with two-stroke engines. In this article, we examine the annual detection frequency, number of new source detections, and concentration of MTBE detected in California's public drinking water groundwater and surface water sources from 1995 to 2002. This work builds on our previous evaluations of California's water quality monitoring database. However, it is unique in that it includes separate evaluations for groundwater and surface water sources that are of greatest concern to regulators, and which are likely being used for current public consumption. Our evaluations also include full-year data for 2002 (which have not been published previously) and an analysis of how the sampling and reported detections of MTBE vary by geographic location. We find that MTBE was generally detected (at any level) in approximately 0.5-0.9% and 0.2-0.4% of all groundwater sources assuming a one-detection and two-detection criterion, respectively. The overall detection frequency for MTBE in surface water sources is significantly higher than for groundwater sources, although these surface water detections appear to have substantially declined since 1996 (e.g., 7-9% for all surface water sources during 1996 to 1999 and 4% for all surface water sources during 2000 to 2002, assuming a one-detection criterion). The detection frequency of MTBE concentrations at or above the state drinking water standards in all drinking water sources (both groundwater and surface water sources) and the subset of drinking water sources that are likely to currently be delivered to consumers is markedly lower (and often zero). Despite the significant increase in water sampling over time, the number of new drinking water sources found to contain MTBE in California has not increased at the same rate and appears to have remained relatively stable or to have decreased since 1998. The data also show that nearly all of the 58 counties in California have routinely sampled at least some of their groundwater and surface water sources for MTBE over the last 8 years. Geographical evaluations show that MTBE has been detected (at least once) in groundwater sources in 34 counties and in surface water sources in 18 counties but has only been detected routinely (i.e., for 3 or more years) in 16 and 7 counties, respectively. Detected concentrations of MTBE are also generally below state drinking water standards, particularly for surface water sources. In short: (1) MTBE is rarely found in California groundwater or surface water sources that are of greatest concern to regulators or the public, and (2) drinking water detections of MTBE are expected to decline in the future due to the pending phase-out of MTBE and recent regulatory programs aimed at controlling gasoline releases from underground storage tanks and two-stroke-engine watercraft.     

Salem Revisited: Updating the MTBE Controversy

I am wronged. It is a shameful thing that you should mind these folks that are out of their wits.* *Statement of Martha Carrier (excerpt), hanged as a witch on 19 August, 1692 in Salem, Massachusetts. In all, 20 innocent persons were executed in 1692 as a result of the hysteria attending the Salem witch trials. After the executions, the court was prohibited from "reliance on spectral and intangible evidence". No prosecutions were successful thereafter. See generally, The Salem Witch Trials 1692: A Chronology of Events , at www.salemweb.com/memorial This article provides background information regarding the emerging controversies involving methyl tert -butyl ether (MTBE) and litigation involving leaking underground storage tanks (USTs) in general. It examines (1) the administrative, legislative and litigation history of MTBE in the context of the Clear Air Act and state environmental statues; (2) the importance of applicable RCRA (Resource Conservation and Recovery Act) deadlines regarding UST compliance in these cases; (3) the question of MTBE toxicity for personal injury claims; and (4) the scope of damages available in cases filed by plaintiffs who are not physically impacted by contamination. The authors conclude that the MTBE controversy does not appear to be a legitimate public health or environmental crisis, but rather is yet another speculative product of the American legal industry.     

Characterisation of prompt and delayed atmospheric radioactivity releases from underground nuclear tests at Nevada as a function of release time

A database with information on about 500 cases of atmospheric radioactivity releases from underground nuclear tests is analysed. The data are statistically evaluated and systematically aggregated in order to characterise prompt uncontrolled as well as delayed operational releases of radioactivity into the atmosphere. The focus is put on the latter. The reported data compare well with theoretically derived xenon activities for reasonable nuclear test scenarios. Conclusions are drawn on the main features of releases that can be expected from underground nuclear tests as a function of release time. These findings are relevant for developing and validating methods to be applied in global monitoring of atmospheric radioactivity with respect to indications of an underground nuclear explosion.     

Occurrence of polycyclic aromatic hydrocarbons in surface sediments of a highly urbanized river system with special reference to energy consumption patterns

Sediment samples collected from downstream of the Dongjiang River, a highly urbanized river network within the Pearl River Delta of South China, were analyzed for 28 polycyclic aromatic hydrocarbons (PAHs). Total concentrations of 28 PAHs, 16 priority PAHs designated by the United States Environmental Protection Agency (USEPA) and the seven carcinogenic PAHs classified by the USEPA ranged from 480 to 4600, 100 to 3400 and 10 to 1700 ng/g dry weight, respectively. Principal component analysis-based stepwise multivariate linear regression showed that sediment PAHs were predominantly derived from coal combustion, refined fossil fuel combustion and oil spills, accounting for 37%, 32% and 23%, respectively, of the total loading. The levels of sediment PAHs remained steady from 2002 to 2008, during which fossil fuel consumption had doubled, probably reflecting efforts to control PAH emissions from fossil fuel combustion. Finally, use of natural gas and liquefied petroleum gas in automobiles should be encouraged to improve environmental quality.     

Electrocatalytic biofilm reactor for effective and energy-efficient azo dye degradation: the synergistic effect of MnOx/Ti flow-through anode and biofilm on the cathode

● MnO _x /Ti flow-through anode was coupled with the biofilm-attached cathode in ECBR. ● ECBR was able to enhance the azo dye removal and reduce the energy consumption. ● Mn^IV=O generated on the electrified MnO _x /Ti anode catalyzed the azo dye oxidation. ● Aerobic heterotrophic bacteria on the cathode degraded azo dye intermediate products. ● Biodegradation of intermediate products was stimulated under the electric field. Dyeing wastewater treatment remains a challenge. Although effective, the in-series process using electrochemical oxidation as the pre- or post-treatment of biodegradation is long. This study proposes a compact dual-chamber electrocatalytic biofilm reactor (ECBR) to complete azo dye decolorization and mineralization in a single unit via anodic oxidation on a MnO_x/Ti flow-through anode followed by cathodic biodegradation on carbon felts. Compared with the electrocatalytic reactor with a stainless-steel cathode (ECR-SS) and the biofilm reactor (BR), the ECBR increased the chemical oxygen demand (COD) removal efficiency by 24 % and 31 % (600 mg/L Acid Orange 7 as the feed, current of 6 mA), respectively. The COD removal efficiency of the ECBR was even higher than the sum of those of ECR-SS and BR. The ECBR also reduced the energy consumption (3.07 kWh/kg COD) by approximately half compared with ECR-SS. The advantages of the ECBR in azo dye removal were attributed to the synergistic effect of the MnO_x/Ti flow-through anode and cathodic biofilms. Catalyzed by Mn^IV=O generated on the MnO_x/Ti anode under a low applied current, azo dyes were oxidized and decolored. The intermediate products with improved biodegradability were further mineralized by the cathodic aerobic heterotrophic bacteria (non-electrochemically active) under the stimulation of the applied current. Taking advantage of the mutual interactions among the electricity, anode, and bacteria, this study provides a novel and compact process for the effective and energy-efficient treatment of azo dye wastewater.     

厌氧发酵系统温度的选择和热量平衡

本文分析了厌氧发酵温度的选择和厌氧系统中热量平衡的关系。并运用此关系对薯干酒糟过滤液在冬季最低温度为0℃,夏季最高温度为35℃的地区进行中温和高温厌氧发酵处理中的热量平衡关系分别进行了讨论,证明了对温度为50℃,COD浓度为23g/L的废液进行中温发酵能得到更大的经济效益,但也必须使用所产生的沼气作为能源加热或冷却废液。所需的热量和气温的关系为:Q_t=4.73×105to-3.73×106 (KJ/d)。