Chemical coupling between ammonia, acid gases, and fine particles

The concentrations of inorganic aerosol components in the fine particulate matter (PM(fine)< or =2.5 microm) consisted of primarily ammonium, sodium, sulfate, nitrate, and chloride are related to the transfer time scale between gas to particle phase, which is a function of the ambient temperature, relative humidity, and their gas phase constituent concentrations in the atmosphere. This study involved understanding the magnitude of major ammonia sources; and an up-wind and down-wind (receptor) ammonia, acid gases, and fine particulate measurements; with a view to accretion gas-to-particle conversion (GTPS) process in an agricultural/rural environment. The observational based analysis of ammonia, acid gases, and fine particles by annular denuder system (ADS) coupled with a Gaussian dispersion model provided the mean pseudo-first-order k(S-1) between NH(3) and H(2)SO(4) aerosol approximately 5.00 (+/-3.77)x10(-3) s(-1). The rate constant was found to increase as ambient temperature, wind speed, and solar radiation increases, and decreases with increasing relative humidity. The observed [NH(3)][HNO(3)] products exceeded values predicted by theoretical equilibrium constants, due to a local excess of ammonia concentration.     

臭氧与TiO2/UV协同降解对氯苯酚

利用O3／UV、TiO2／UV和O3／TiO2／UV降解对氯苯酚表明，臭氧与TiO2／UV具有明显的协同作用，如在本实验条件下降解5min后，上述3者对对氯苯酚的去除率分别为55％、10％和77%。O3／TiO2／UV协同作用的本质是由于臭氧能带走二氧化钛光致电子空穴对中的电子，从而产生了更多的羟基自由基，加速了有机物的降解。     

Removal of NOx from flue gas with iron filings reduction following complex absorption in ferrous chelates aqueous solutions

A novel process for removal of nitrogen oxides (NOx) from flue gases with iron filings reduction following complex absorption in iron-ethylenediaminetetraacetic acid aqueous solution is proposed. The reaction mechanism involved in the process is discussed briefly. The parameters influencing the process, including the concentration of ferrous chelates, initial pH, amount of iron filings, temperature, flow rate of the flue gas, and inlet nitric oxide concentration and oxygen content of the flue gas, are researched in detail. The optimal NOx removal conditions are established. The regeneration and circular utilization of the absorption solution also is studied.     

醋酸乙烯生产过程废触媒的资源化回收

采用正交实验研究了微波、超声波条件对废触媒解吸效果的影响,对比实验结果表明,1次微波2次超声波联用技术锌的洗脱率较高,回收的活性炭超过了林业局粉状活性炭二级品指标.用洗脱的醋酸锌溶液制备的磷酸锌符合防锈颜料要求.最终的废液采用电石废渣中和后达到国家废水处理三级排放标准.实现了废触媒的综合回收利用.     

Comparison of quantitation of polychlorinated dibenzodioxins and polychlorinated dibenzofurans in complex environmental samples by high resolution gas chromatography with flame ionization, electron capture and mass spectrometric detection

A complete separation of PDDD and PCDF from a complex sample matrix by a two-step HPLC clean-up procedure shows the feasibility of analysis of PCDD and PCDF using less expensive instruments. This is demonstrated by a comparison of quantitative results of PCDD and PCDF in a complex flyash sample analyzed using GC/FID, GC/ECD, and GC/MSD.     

喷流塔脱硫除尘技术研究

基于强化喷淋装置传质过程,开发了一种结构简单、压降小、效率高、生产能力大的脱硫除尘装置——喷流塔。实验表明,液气比L/G=15L/m3时,除尘效率≥994%,流化层压降≤300Pa;采用CaCa双碱法脱硫工艺,pH=7～8、L/G=10～12L/m3时,脱硫效率≥92%,流化层压降≤450Pa。在脱硫操作条件下可同时脱除996%以上的烟尘,适于脱硫除尘一体化操作。     

Characteristics of MnO2 catalytic ozonation of sulfosalicylic acid and propionic acid in water

The characteristics of different types of MnO₂ catalytic ozonation of sulfosalicylic acid (SSal) and propionic acid (PPA) have been investigated in this paper. The experimental results show the dependence of catalytic activity of MnO₂ on organic compounds and the pH of solutions, but it is independent on the type of MnO₂. For example, three types of MnO₂ have not any catalytic activity when ozonation of PPA under the condition of this experiment. All MnO₂ catalytic ozonation of SSal at pH=1.0 have a greater total organic carbon removal than ozonation alone has, however, at pH=6.8 and 8.5, catalytic efficiency is not observed. Furthermore, the batch experimental results indicate that there are no direct relationship between the activity of metal oxide catalytic decomposition of ozone and that of its catalytic degradation of organic compounds.     

上海地区经济能源与温室效应

本文分析了上海及近邻地区经济发展与温室效应的关系，提出以煤为主的能源消费结构以及不合理的经济结构是加剧温室效应的主要原因并探讨了削弱温室效应的措施。     

Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing

Agricultural activity is one of the most important sources of aerosol particles. To understand the mass distribution and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing, particle samples were collected using a microorifice uniform deposit impactor (MOUDI) in the summer of 2004 in a suburb vegetable field. The distribution of the particles and their inorganic water-soluble ions in the diameter range of 0.18–18 μm were measured. The dominant fine particle ions were SO₄ ^2?, NO₃ ^?, and NH₄ ⁺. The association of day-to-day variation of the concentration of these ions with temperature, humidity, and solar radiation suggested that they are formed by the reaction of NH₃ released from the vegetable field with the acid species produced from photochemical reactions. Fine particle K⁺ is likely from vegetation emission and biomass burning. Coarse particles like Ca²⁺, Mg²⁺, NO₃ ^?, and SO₄ ^2? are suggested to come from the mechanical process by which the soil particle entered the atmosphere, and from the reaction of the acid species at the surface of the soil particle. The results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields, and vegetable fields in suburban Beijing contribute significantly to the aerosol particle.     

污水深度处理中3种过滤法的技术性能研究

以城市污水回用为目的，研究了污水深度处理中的过滤技术，结果陶瓷－石英砂双层滤料的滤柱，在滤速为５．２ｍ／ｈ时，通过直接过滤即可将污水处理厂二级出水中的悬浮物几乎全部去除，且过滤周期可达６１．２－７２．１ｈ。