Rapid decolorization of Acid Orange II aqueous solution by amorphous zero-valent iron

Some problems including low treatment capacity, agglomeration and clogging phenomena, and short working life, limit the application of pre-treatment methods involving zero-valent iron (ZVI). In this article, ZVI was frozen in an amorphous state through a melt-spinning technique, and the decolorization effect of amorphous ZVI on Acid Orange II solution was investigated under varied conditions of experimental variables such as reaction temperature, ribbon dosage, and initial pH. Batch experiments suggested that the decolorization rate was enhanced with the increase of reaction temperature and ribbon dosage, but decreased with increasing initial solution pH. Kinetic analyses indicated that the decolorization process followed a first order exponential kinetic model, and the surface-normalized decolorization rate could reach 2.09 L/(m². min) at room temperature, which was about ten times larger than any previously reported under similar conditions. Recycling experiments also proved that the ribbons could be reused at least four times without obvious decay of decolorization rate and efficiency. This study suggests a tremendous application potential for amorphous ZVI in remediation of groundwater or wastewater contaminated with azo dyes.     

一种新型生物絮凝剂FM-2絮凝特性及稳定性考察

文章对絮凝剂FM-1的储存稳定性以及絮凝活性分布进行了考察,发现其絮凝活性物质主要分布于上清液之中,加之储存稳定性较差的特点,为絮凝剂FM-2的制备提供了前提。絮凝剂FM-2的最佳絮凝率高达99.21%,其储存时间较长,30 d内其絮凝率可保持在90%以上;而且还具有较好的热稳定性,当加热温度从70℃升高到100℃,其絮凝率均保持在95%以上。     

城市轨道交通浮置式减振措施的减振降噪效果

从分析轨道交通地下隧道振动传播特征出发,说明了地下振动的传播规律,并给出了不同埋深条件下地下振动影响范围的经验公式;结合地下振动激发频率特征的分析,对减振措施的减振效果的合理评价量进行了分析,指出采用Z计权减振效果评价量将获得与实际应用效果一致的降噪效果。结合两种浮置式减振措施减振降噪效果的实测,指出浮置板道床的减振效果应采用安装减振垫浮置板道床前后桥面的Z振级差来评价,而不宜采用轨面与桥梁直接的振级落差来评价。对橡胶减振垫以及钢弹簧浮置板的实测减振降噪效果进行了介绍。     

高速铁路车轮减振降噪优化方法

高速铁路车轮的振动辐射噪声在轮轨滚动辐射噪声中占有很大的比重,而且在1500Hz以上的频段内占主导,对列车车轮进行优化设计,通过改变车轮的形状,可以达到较好的减振降噪效果。本文对高速铁路车轮优化方法进行详细的分析评论,并提出相应的问题和改进的方向。     

我国钢铁生产企业氮氧化物减排形势研究

针对国家"十二五"氮氧化物减排的紧迫形势,介绍了我国钢铁企业排放氮氧化物污染现状,提出烧结工序烟气氮氧化物控制是钢铁生产企业氮氧化物减排的重点,在对相关技术优缺点进行分析的基础上,总结了存在的主要问题、困难和发展趋势,提出了钢铁行业氮氧化物减排的对策和建议,为我国氮氧化物污染控制提供支撑。     

BAF去除氨氮关键影响因素研究

为探讨曝气生物滤池去除氨氮的关键因素,选取沈阳仙女河污水处理厂(40万t/d)现场进行实地研究。通过测定不同条件下(pH、进水COD浓度、溶解氧、温度、水力负荷)的氨氮去除率,并进行主成分分析结果显示,影响BAF工艺脱氮的关键因素是温度、溶解氧和水力负荷。当温度在14~30℃之间时,氨氮的去除率一直维持较高,当温度低于14℃时,氨氮的去除率较低;随着溶解氧浓度的增大,氨氮的去除率也随之升高,当溶解氧增加到5.6 mg/L时,氨氮的去除率达到80%~90%,接近饱和状态;在水力负荷为3.08~4.15 m3/(m.2h)之间时,氨氮的去除率上升,超过该值,则氨氮去除率下降。     

放射源在线监控系统设计与应用

为了防止在使用放射源时发生脱落、丢失、超标使用、私自转移等情况,最大限度避免辐射安全事故,有必要设计建立放射源在线监控系统,对放射源放射性指标(辐射剂量率)及所处位置(经纬度)实行连续的自动监测。并通过各级监管平台设置放射源超标、异动等报警程序,全面提升放射源科学监管水平。     

Absorption characteristics of new solvent based on a blend of AMP and 1,8-diamino-p-menthane for CO2 absorption

Aqueous 1,8-diamino-p-menthane (KIER-C3) and commercially available amine solutions were tested for CO₂ absorption. A 2-amino- 2-methyl-1-propanol (AMP) solution with an addition of KIER-C3 showed 9.3% and 31.6% higher absorption rate for CO₂ than the AMP solution with an addition of monoethanolamine (MEA) and ammonia (NH₃), respectively. The reaction rate constant for CO₂ absorption by the AMP/KIER-C3 solution was determined by the following equation: k_2,AMP/C3 = 7.702×10⁶ exp (-2248.03/T). A CO₂ loading ratio of the AMP/KIER-C3 solution was also 2 and 3.4-times higher than that of the AMP/NH3 solution and the AMP/MEA solution, respectively. Based on the experimental results, KIER-C3 may be used as an excellent additive to increase CO₂ absorption capability of AMP.     

零价铁还原和吸附去除水中污染物的研究进展

近年来,零价铁以其低毒、廉价、易操作且对环境不会产生二次污染等优点,在水污染治理中受到重视。文章介绍了零价铁处理污水的机理,对利用零价铁的还原和吸附作用去除污水中的氯代有机物、硝基芳香族化合物、偶氮染料、重金属、高氯酸盐、硝酸盐等的研究情况进行了综述,指出了零价铁废水处理技术的研究方向。     

生物质发电项目碳排放计算方法应用研究

生物质发电是将废弃生物质变成可再生能源得以充分利用,这些工程将减少来自于生物质自然腐烂和无控燃烧产生的温室效应,这不仅节约了煤炭的同时也减少了二氧化碳的排放。本文中以某生物质项目发电为例,根据CDM方法学ACM0006计算了该项目的减排量。结果表明,该项目10年间共减少了二氧化碳排放量2,075,140 t,给我国带来了可观的经济效益和环境效益。