紫外-生物过滤联合工艺处理VOCs的研究

挥发性有机物引起的环境污染问题已日益严重,高浓度、难降解挥发性有机物的处理是当前亟待解决的问题。单一的生物过滤技术对挥发性有机物的去除效果并不理想,在传统生物过滤工艺前增加紫外预处理单元,构建了紫外-生物过滤联合工艺。紫外-生物过滤联合工艺是处理高浓度、难降解挥发性有机物的一个有效途径,也是挥发性有机物控制技术研究的前沿领域。文章系统介绍了紫外-生物过滤联合工艺的研究背景和在国内外的研究进展,并阐述了紫外-生物过滤联合工艺对挥发性有机物的去除性能、紫外-生物过滤联合工艺组合优势、紫外预处理对生物过滤单元影响机理研究和紫外-生物过滤联合工艺模拟模型,最后对紫外-生物过滤联合工艺的工程应用前景进行了展望。     

荥阳地震台背景干扰及处理

利用荥阳地震台形变资料,对自然因素、人为影响、停电以及其他仪器故障等各种干扰事件进行了总结,分析了其影响幅度及机理,为利用形变资料识别并消除干扰、准确捕捉地震短临异常提供了可借鉴的依据。     

地级市域工业VOCs排放源产排特性及其控制技术应用现状:以秦皇岛市为例

对秦皇岛市609家工业企业VOCs的源排放和污染控制技术做了调研.结果表明,VOCs排放源排放的气体流量以石油加工、炼焦和核燃料加工业最高(105m3·h-1).其余行业主要集中在103~105m3·h-1之间.各行业源排放的VOCs浓度均小于1 000 mg·m-3,各行业的VOCs排放速率差异性较大,介于50~10 000 g·h-1之间.其中交通运输设备制造业、石油加工、炼焦和核燃料加工业、机械设备制造业、印刷和记录媒介复制业及化学原料和化学制品制造业的排放浓度和排放速率均较高.和国内之前的调查研究相比,秦皇岛市工业企业VOCs的排放水平相对较低.此次调研的609家工业企业中拥有VOCs处理设施的案例共109个.吸附技术应用的占比最大(69%).其次为吸收技术(19%).     

华北地区沙尘天气垂直气溶胶直接辐射强迫

利用CALIOP数据和SBDART（Santa Barbara DISORT Atmospheric Radiative Transfer）辐射传输模式研究了2013~2016年华北地区8d沙尘天气气溶胶及其直接辐射强迫垂直分布特征,分析了气溶胶垂直分布和光学特性对直接辐射强迫的影响.结果表明,气溶胶集中分布在地表及以上3km范围,其中纯净沙尘型和污染沙尘型气溶胶位于上层,污染大陆型气溶胶和烟雾位于下层.大气层顶、地表和大气层的日均气溶胶直接辐射强迫分别是-38.41~-88.44,-74.03~-225.86,9.06~137.42W/m².0~8km高度范围气溶胶直接辐射强迫是负值,且随着高度的增加绝对值逐渐减小.气溶胶垂直分布对大气层顶、地表和大气层的直接辐射强迫影响较小,但对直接辐射强迫垂直分布影响较大,由气溶胶廓线差异造成的同一高度层气溶胶直接辐射强迫最大差值能达到31.18W/m².气溶胶光学厚度和单次散射反照率对直接辐射强迫影响明显.消光能力相同时,吸收性气溶胶对短波太阳光的衰减作用大于散射性气溶胶,后向散射比例大的气溶胶大于后向散射比例小的气溶胶.     

中国实施清洁发展机制的潜力分析

建立了一个全球碳排放贸易局部均衡模型(TRCW),用于分析中国实施清洁发展机制(CDM)的市场潜力和市场结构.模型结合相关国际协议的规定,考虑了美国的退出、碳汇项目、热空气规模、交易成本、适应性基金、垄断供给等现实因素.结果表明,在马拉喀什协议下,中国的CDM市场规模大大缩小,仅为61MtC/a,利润收入约1.5亿$/a,其中重工业和电力分别约占41%和20%左右;如果俄罗斯不出售其拥有的热空气,中国的CDM规模将提高67%;在CDM市场上中国几乎不存在垄断力量.     

Advances in airborne microorganisms detection using biosensors: A critical review

• Airborne microorganism detection methods are summarized. • Biosensors play an important role in detecting airborne microorganisms. • The principle of biosensor detection of airborne microorganisms is introduced. • The application and progress of biosensor in recent years is summarized. • The future perspectives of biosensor are identified. Humanity has been facing the threat of a variety of infectious diseases. Airborne microorganisms can cause airborne infectious diseases, which spread rapidly and extensively, causing huge losses to human society on a global scale. In recent years, the detection technology for airborne microorganisms has developed rapidly; it can be roughly divided into biochemical, immune, and molecular technologies. However, these technologies still have some shortcomings; they are time-consuming and have low sensitivity and poor stability. Most of them need to be used in the ideal environment of a laboratory, which limits their applications. A biosensor is a device that converts biological signals into detectable signals. As an interdisciplinary field, biosensors have successfully introduced a variety of technologies for bio-detection. Given their fast analysis speed, high sensitivity, good portability, strong specificity, and low cost, biosensors have been widely used in environmental monitoring, medical research, food and agricultural safety, military medicine and other fields. In recent years, the performance of biosensors has greatly improved, becoming a promising technology for airborne microorganism detection. This review introduces the detection principle of biosensors from the three aspects of component identification, energy conversion principle, and signal amplification. It also summarizes its research and application in airborne microorganism detection. The new progress and future development trend of the biosensor detection of airborne microorganisms are analyzed.     

Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on activated carbon fibers coated TiO

TiO₂ supported on active carbon fiber (TiO₂/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO₂/ACF were studied, and then, the purification capability of TiO₂/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO₂/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH = 30% is the optimal condition for purifying toluene in our experimental system.     

北京市2005年夏季大气颗粒物污染特征及影响因素

对2005年7～8月北京市不同功能区8个采样点PM10和PM2.5的浓度水平、空间分布、PM10/PM2.5比值进行了分析,并讨论了PM10和PM2.5的日变化特征及影响因素.结果表明,北京市夏季PM10和PM2.5日均浓度为155.37 μg/m3和87.70 μg/m3,分别为国家二级标准和美国PM2.5标准的1.04倍和1.35倍;PM2.5、PM10浓度在不同功能区存在一定差异;PM2.5和PM10的日变化以白天高,夜间低为主,且不同功能区的最高值对应于城市居民活动的不同高峰期;在湿度较高的情况下,PM2.5、PM10与湿度呈一定正相关性,且湿度对PM2.5的影响更大;降水前后PM2.5、PM10浓度变化情况表明降水的主要作用是清除粗粒子,对PM2.5的影响则较小.     

中国城市污水处理厂资源配置效率的比较

采用平均生产函数模型、边界生产函数以及数据包络分析(DEA)模型3种方法,对中国81个污水处理厂的样本观测数据,从不同角度进行了比较研究,分别得出上述3种模型对产出弹性、技术效率和规模经济性等主要指标的模拟结果.研究发现,资本对我国城市污水处理厂的产出弹性最大(0.507),其次是运营电耗(0.415),再次为劳动力;我国污水厂普遍处于规模报酬率递增阶段,样本总体的规模报酬率为1.11;根据DEA的分析结果,列出了81个样本污水厂的效率排序清单,这将有助于制定行业绩效标准.     

SO_2和NO_x基准线排放因子的计算研究

根据清洁发展机制(CDM)执行理事会(EB)公布的电力系统排放因子计算工具,结合文献调研数据,计算了全国7个电网的SO2和NOx基准线排放因子,比较了不同电网CDM项目的污染物减排效益以及不同类型CDM项目的减排效益.结果表明,华中电网的CDM项目单位供电量的SO2减排效益最高,东北电网的最低;而对于项目单位供电量的NOx减排效益,最高的是东北电网,最低的是南方电网和海南电网.目前,CDM项目在各电网的分布与其单位供电量的污染物减排效益存在着不平衡的状况.如南方电网开发CDM项目较多,其项目单位供电量的污染物减排效益并不高.对于不同类型的CDM项目,风电及太阳能发电项目的污染物减排效益相对较高.