Destruction of PCDD/Fs by SCR from flue gases of municipal waste incinerator and metal smelting plant

Partitioning of PCDD/F congeners between vapor/solid phases and removal and destruction efficiencies achieved with selective catalytic reduction (SCR) system for PCDD/Fs at an existing municipal waste incinerator (MWI) and metal smelting plant (MSP) in Taiwan are evaluated via stack sampling and analysis. The MWI investigated is equipped with electrostatic precipitators (EP, operating temperature: 230 degrees C), wet scrubbers (WS, operating temperature: 70 degrees C) and SCR (operating temperature: 220 degrees C) as major air pollution control devices (APCDs). PCDD/F concentration measured at stack gas of the MWI investigated is 0.728 ng-TEQ/Nm(3). The removal efficiency of WS+SCR system for PCDD/Fs reaches 93% in the MWI investigated. The MSP investigated is equipped with EP (operating temperature: 240 degrees C) and SCR (operating temperature: 290 degrees C) as APCDs. The flue gas sampling results also indicate that PCDD/F concentration treated with SCR is 1.35 ng-TEQ/Nm(3). The SCR system adopted in MSP can remove 52.3% PCDD/Fs from flue gases (SCR operating temperature: 290 degrees C, Gas flow rate: 660 kN m(3)/h). In addition, the distributions of PCDD/F congeners observed in the flue gases of the MWI and MSP investigated are significantly different. This study also indicates that the PCDD/F congeners measured in the flue gases of those two facilities are mostly distributed in vapor phase prior to the SCR system and shift to solid phase (vapor-phase PCDD/Fs are effectively decomposed) after being treated with catalyst. Besides, the results also indicate that with SCR highly chlorinated PCDD/F congeners can be transformed to lowly chlorinated PCDD/F congeners probably by dechlorination, while the removal efficiencies of vapor-phase PCDD/Fs increase with increasing chlorination.     

大气污染物扩散模式的应用研究综述

应用大气污染物扩散模式可以模拟不同尺度、气象、地形条件下工业污染物在大气中的输送与扩散特征,为大气监测、城市环境规划和空气质量预报等工作提供科学依据.归纳了目前广泛应用于模拟工业污染物扩散的模式,着重介绍了近年来国内外对这些模式的主要应用研究进展,比较了各模式在应用上的优缺点,并对大气污染物扩散模式的应用研究前景进行了讨论.     

噪声损害鉴定方法和程序探讨

目前噪声污染问题正成为人民群众日益关心的突出问题,对于解决噪声污染引起的各种纠纷和诉讼,开展损害鉴定是重要手段,而目前国家并未出台噪声损害鉴定的相关技术导则,文章结合噪声相关法律法规、技术标准及实践经验,总结开展噪声损害鉴定的方法和程序及注意事项,为相关从业人员提供参考.     

五氯酚在表面微层水与表层水间的分配行为

利用玻璃板采样器采工分析市南排污河下游至渤变入口处水体表面微层（ＳＭ）中五氯酚（ＰＣＰ）的富体系数,然后在实验室中进行了微宇宙模拟实验,初步探讨了富集原因,现场测结果表明：ＰＣＰ在水体表面微层中有一定程度的富集一般富集系数在１．１６～４．１１之间;其富集可能与悬浮颗粒物在ＳＭ中的富集、盐度、大气沉降过程等有关,与ＴＯＣ无关。实验室研究结果表明：ＰＣＰ在水体表面微层中富集倍数随悬浮颗粒物浓度和盐度增     

Gasoline prices and traffic safety in Mississippi

Problem

Limited literature suggests that gasoline prices have substantial effects on reducing fatal crashes. However, the literature focuses only on fatal crashes and does not examine the effects on all traffic crashes.

Methods

Mississippi traffic crash data from April 2004–December 2008 from the Mississippi Highway Patrol and regular-grade unleaded gasoline price data from the Energy Information Administration of the U.S. Department of Energy were used to investigate the effects of gasoline prices on traffic safety by age, gender, and race.

Results

Gasoline prices have both short-term and intermediate-term effects on reducing total traffic crashes and crashes of females, whites, and blacks. The intermediate-term effects are generally stronger than the short-term effects. Gasoline prices also have short-term effects on reducing crashes of younger drivers and intermediate-term effects on older drivers and male drivers.

Impact on Industry

Higher gasoline taxes reduce traffic crashes and may result in additional societal benefits.     

关注地下蕴藏的“大热源”

<正>伴随着经济的高速发展,电荒、水荒、油荒接踵而至,拉闸限电、煤炭紧缺、油价上涨,一个接着一个,让人无可奈何,"能源危机"已成为人们心头挥之不去的阴霾。而来自能源专家的建议却令人为之一振。2009年8月30—31日召开的全     

自然资源价值论及其在环境影响评价中的应用

对自然资源价值理论进行了论述,运用环境经济学方法分析了现行环境影响评价之不足,提出应用自然资源价值对环境损益进行定量分析,是提高环境影响评价有效性的必然途径.最后介绍了自然资源的价值评价方法.     

提高钠离子交换器工作交换容量浅析

分析了钠离子交换器影响工作交换容量的因素,研究了交换剂在交换器中工作情况的层状特性,低盐耗条件下再生程度,浓度与工作交换容量关系,再生液流速根据交换剂反应的特性一般控制在4-8 m/h范围时合适,防止交换剂污染也是保证提高钠离子交换器工作交换容量的关键.     

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium phosphate residue

In China, safe disposal of hazardous waste is more and more a necessity, urged by rapid economic development. The pyrolysis and combustion characteristics of a residue from producing monopotassium phosphate (monopotassium phosphate residue), considered as a hazardous waste, were studied using a thermogravimetric, coupled with Fourier transform infrared analyzer (TG-FTIR). Both pyrolysis and combustion runs can be subdivided into three stages: drying, thermal decomposition, and final devolatilization. The average weight loss rate during fast thermal decomposition stage in pyrolysis is higher than combustion. Acetic acid, methane, pentane, (acetyl) cyclopropane, 2,4,6-trichlorophenol, CO, and CO₂ were distinguished in the pyrolysis process, while CO₂ was the dominant combustion product.     

脱硫脱硝用煤质颗粒活性炭及试验方法国家标准解读

本文介绍了GB/T 30201-2013《脱硫脱硝用煤质颗粒活性炭》及GB/T 30202.1--5-2013《脱硫脱硝用煤质颗粒活性炭试验方法》的编制背景、主要内容、试验验证情况等,本系列标准于2014年发布实施,它对规范我国脱硫脱硝用煤质颗粒活性炭的科研、生产、应用以及推动干法脱硫脱硝减少二氧化硫、氮氧化物的排放将起到重要作用。