Study on low-temperature plasma γ-Al2O3 catalytic viscosity reduction of polyacrylamide solution

The wide use of polyacrylamide (PAM) in enhanced oil recovery generates a large amount of polymer-bearing wastewater featuring high viscosity and difficult viscosity reduction, making the treatment of wastewater increasingly difficult. In this paper, the experimental study on reducing the viscosity of wastewater containing polyacrylamide by using the plasma generated by dielectric barrier discharge (DBD) and the synergistic effect of catalyst γ-Al₂O₃ is carried out. The law of plasma reducing the viscosity of wastewater containing polyacrylamide is studied under the different conditions of amounts of γ-Al₂O₃ catalyst, discharge voltages, and initial concentrations of polyacrylamide-containing wastewater. The mechanism of viscosity reduction of polyacrylamide is studied through environmental scanning electron microscope (ESEM), Fourier transform infrared (FTIR) spectrometer, and X-ray photoelectron spectroscopy (XPS). The results show that the catalytic viscosity reduction is the best when the discharge voltage is 18 kV and the discharge time is 15 min. With the increase in the input of the γ-Al₂O₃ catalyst, the viscosity of the PAM solution decreases gradually. When the amount of γ-Al₂O₃ is 375 mg, the shear rate changes from 0.5 1/sec to 28 1/sec, and the viscosity of the solution containing polyacrylamide changes from 434.5 mPa·s to 40.2 mPa·s. The viscosity reduction rate of the PAM solution is 90.7%. After the catalytic viscosity reduction, the functional groups of polyacrylamide do not change much. The elemental composition of the catalyst has not changed, which is still Al, C, and O.

     

The combined effect of titanium dioxide nanoparticles and cypermethrin on male reproductive toxicity in rats

Environmental Science and Pollution Research - Titanium nanoparticles and pyrethroid pesticides are now being widely used in industrial, agriculture, and biomedical applications. In recent years,...     

我国汽车排气污染现状与发展

从汽车保有量,油口消耗、污染物排放和城市大气环境质量等方面分析了我国汽车污染现状及２０００年和２０１０年２个时段的发展趋势,从节能,净化和管理的角度初步分析了削减汽车污染物排放的综合对策。     

三元缔合物抑制分光光度法测定痕量氟

利用氟离子对锆－水杨基荧光酮－溴化十六烷基三甲基铵三元缔合物形成的竞争抑制作用,建立了测定痕量氟的抑制分光光度法,确定了测定的最佳条件为：「ＳＡＦ」＝６．０×１０＾－５ｍｏｌ．Ｌ＾－１「ＣＴＭＡＢ」＝８．０×１０＾－４ｍｏｌ．Ｌ＾－１,「Ｚｒ（ＩＶ）」＝１．０μｇ．ｍｌ＾－１,「ＨＣｌ」＝０．０８ｍｏＬ．Ｌ＾－１,２５℃。     

线源扩散的快速模拟

提出了一种计算风向与线源成任意角时任意长地面线源大气扩散的简化模式。通过与数值积分方法计算结果的比较表明,模式的最大相对误差在风向与线源平行时最大,但不超过18％。随风向与线源夹角的增大,相对误差迅速减小,当夹角大于5°时,已小于2％。为城镇公路网大气扩散的快速、准确模拟提供了新手段。     

地理信息系统在环境领域中的应用

简要介绍了地理信息系统在环境领域中的应用,它将成为社会可持续发展的有效辅助决策的支持工具。     

Dynamic Changes of Sandy Land in Northwest of Beijing, China

The area northwest of Beijing is one of the most important regions where many organizations invest and pay most attention. The environmental problems in this region affect not only Beijing but also the surrounding area. Based on observation of the characteristics of the change in sandy land, this study classified four types of dynamic change of sandy land, including extended sandy land, the reversely changed sandy land, the potential sandy land and no change in sandy land. Then the process and the trend of changes in sandy land and their environmental impact on the area northwest of Beijing were analyzed. The results show that the area of sandy land has increased in this region in the period of 1991 to 2002. Change between sandy land and grassland was the dominant change. It is found that the monitoring zones of Hunshandake sandy land and north of Yin Shan are regions with high ratio of extended sandy land, and are connected with widespread potential change of sandy land. This implies that these two regions have a high probability of increase in sandy land in the future. On the other hand, in the monitoring zone of Horqin sandy land and Ba Shang Plateau and its surrounding area, desertification had been controlled and the area of sandy land is expected to decrease. This indicates that the direction of the sandstorm to Beijing is expected to gradually move to the northwest. Furthermore, the decreases in sandy land and the reversing change from arable land to grassland and forests in the study region will affect the land quality and atmosphere. And the logistic multiple regression (LMR) model was employed to better understand the complexity and processes of increases in sandy land. This model predicts that there is a high probability of increases in sandy land in north of Siziwang Banner, Zhengxiangbai Banner and Zhenglan Banner. Finally, suggestions to the ecological construction of the study area have been proposed.     

天然气净化厂放空废气对环境的影响及控制措施

天然气净化厂除正常生产有工艺废气排放外,传统装置检修开停产过程、供电或设备异常情况下,会有大量酸气、原料气通过放空火炬燃烧后排放。文章主要分析了天然气净化装置放空废气排放情况及其对周边环境的影响,阐述了异常放空、检修开停产过程原料气和酸气放空的控制措施及其环境效益。     

钻井废物综合治理技术的应用

针对急需解决的钻井废水、废气治理问题,以钻井作业大功率柴油机废气余热回收利用为出发点,研制了钻井废水废气综合治理设备。通过现场试验对钻井废水、废气治理效果及噪声影响的分析,试验结果表明,日处理钻井废水可达11～13m3/d,柴油机废气中污染物排放有一定程度的降低,柴油机高频噪声得到较明显降低,并有利于增加柴油机扭距。     

关于推动青海省环境会计工作的若干思考

随着人口的剧增和社会需求的臌胀,环境问题日渐引起各国政府普遍关注。进入20世纪90年代,越来越多的西方国家把环境损益核算纳入会计研究的领域,逐步出现和形成了环境会计。环境会计制度也是近年来国内会计学界热议的话题。文章在把握我国环境会计概念的基础上,对环境会计在推动青海省环境保护的必要性进行了阐述,提出了建立环境会计促进青海省社会经济可持续发展的几点建议。