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31.
A European scale network was established in 2006 as part of the NitroEurope Integrated Project to infer reactive nitrogen (Nr) dry deposition fluxes, based on low-cost sampling of gaseous and aerosol species and inferential modelling. The network provides monthly measurements of NH3, NH4+, HNO3 and NO3, as well as SO2, SO42−, HCl, Cl and base cations at 58 sites. Measurements are made with an established low-cost denuder methodology (DELTA) as a basis to: (1) examine temporal trends and spatial patterns across Europe, (2) improve and calibrate inferential modelling techniques to estimate exchange of Nr species, (3) provide best estimates of atmospheric dry N deposition, and (4) permit an analysis of net GHG exchange in relation to atmospheric and agricultural N inputs at the European scale. Responsibility for measurements is shared among seven European laboratories. An inter-comparison of the DELTA implementation by 6 laboratories at 4 test sites (Montelibretti, Italy; Braunschweig, Germany; Paterna, Spain and Auchencorth, UK) from July to October 2006 provided training for the laboratories and showed that good agreement was achieved in different climatic conditions (87% of laboratory site-means within 20% of the inter-laboratory median). Results obtained from the first year of measurements show substantial spatial variability in atmospheric Nr concentrations, illustrating the major local (NH3) and regional (HNO3, NO3, and NH4+) differences in Nr concentrations. These results provide the basis to develop future estimates of site-based Nr dry deposition fluxes across Europe, and highlight the role of NH3, largely of agricultural origin, which was the largest single constituent and will dominate dry Nr fluxes at most sites.  相似文献   
32.
A literature search and survey of Virginia, USA, campgrounds with RV pump-out stations were used to determine whether boat holding-tank deodorant chemicals would have deleterious effects on marina septic systems or package treatment plants. Laboratory studies reported in the literature indicate that these chemical additives could affect septic system function in three ways: (1) active ingredients in the additives can impair sewage degradation in septic tanks, causing sludge buildup and overflow of solids into the drainfield, (2) additive chemicals might enter the drainfield and, in high enough concentrations, reduce the drainfield's ability to degrade waste, or (3) toxic additive chemicals might migrate from the drainfield to ground or surface water. Laboratory studies also show that some ingredients added to holding tanks interfere with functioning of activated sludge treatment process. Experience in the field and in other laboratory studies suggests that factors such as dilution of treated waste with untreated waste and the characteristics of the sewage to be treated can reduce the possibility of damage to septic and activated sludge systems. The campground owners surveyed indicated that they have few problems with their septic systems in spite of the presence of chemical additives in the RV waste. However, most of them practice good septic system maintenance and have devised other means of ensuring that their systems function efficiently. In addition, the survey indicates that most Virginia campgrounds get only seasonal use (as would marinas in Virginia), allowing their systems to recover between peak seasons.  相似文献   
33.
探讨了服装干洗业氯代烃使用情况及污染状况,并分析了目前广泛采用的服装干洗工艺.结果表明,目前服装干洗业全部采用四氯乙烯做干洗剂,沈阳市每年的消耗量在300t左右,干洗过程中约98%的四氯乙烯通过挥发进入大气,2%通过蒸馏残渣排放进入土壤及水体.  相似文献   
34.
北方城市垃圾的回收和利用   总被引:1,自引:0,他引:1  
随着城市垃圾的迅速增长,垃圾污染问题异常尖锐突出,特别是北方城市尤为严重。本文围绕北方城市如何选择合适的垃圾处理技术进行探讨。提出现阶段在大中城市开展综合处理。在小城市采取以卫生填埋为主、堆肥为辅的处理技术,是解决城市垃圾问题的有效途径。  相似文献   
35.
Daily averaged atmospheric concentrations and dry deposition fluxes of particulate metals were measured seasonally at six urban sites and one non-urban coastal site in the Los Angeles region using a conventional total suspended particulate matter (TSP) filter, surrogate surface deposition plates, and a Noll Rotary Impactor (NRI), which provides information about particle size distribution in four size ranges above 6 μm. With the exception of the non-urban site, particulate metal concentrations and deposition fluxes were remarkably uniform spatially and temporally. At all sites there were significant metal concentrations on particles greater than 10 μm, a commonly used upper limit for many air quality monitoring studies, and these large particles were estimated to be responsible for most of the deposited mass of metals. Annual averaged values of deposition rates measured with a surrogate surface were in good agreement with values estimated using theoretical deposition velocities in conjunction with measured size-segregated particle concentrations. Image analysis of particles deposited on NRI stage A, which collects all particles greater than 6 μm, indicated nighttime metal concentrations and deposition at the non-urban coastal site was higher than in the day time due to offshore advection of urban air associated with the diurnal land breeze. Measured enrichments of crustal elements and metals were correlated, indicating efficient mixing of natural and anthropogenic material from different sources, hypothesized to be the result of cyclical resuspension and deposition of dust by moving vehicles and wind.  相似文献   
36.
Kurt B. Carlsson 《Chemosphere》1989,18(9-10):1731-1736
The graph below shows the emitted dioxin - equivalents (Eadon) in grams per year in flue gas from municipal solid waste incinerators with various air pollution control methods for plants of capacity of 200 000 ton municipal solid waste (MSW) per year.

With optimized combustion and an effective air pollution control system the emissions of dioxins can be kept very low (concentrations below 0.1 ng/m3n).

With a very effective air pollution control system the total emission from all Swedish MSW-incinerators burning approximately 1.5 Mton/year will by 1990 be below 2 g/year - a drastic reduction from approximately 15 g today. As the total dioxin - equivalent emission to the environment in Sweden in the year 1987 was almost 500 g we see that municipal waste incineration really is on the way to solve their dioxin problem.  相似文献   

37.
高效干法脱硫剂的研究与开发   总被引:2,自引:0,他引:2  
研究高效干法烟气脱硫剂是提高干法脱硫效率的一种途径,通过分析和探讨CaO和FA的配比、添加剂的种类及加入量、反应温度对脱硫剂脱硫性能的影响,研究了高效干法脱硫剂的制备方法和工艺。  相似文献   
38.
秦芳  张和清 《交通环保》1999,20(5):39-40
在分析港口所属职工食堂及附近饭店的食品、餐具卫生状况及特点的基础上,根据港口及附近餐饮单位个人承包多,卫生经费投入少,食品卫生淡化的现状,对改善卫生状况提出意见和建议。  相似文献   
39.
餐厨泔水去向已经影响到人们切身利益,文中通过对其去向:1、集中后加工处理;2、用来喂猪;3、提取食用油酯(必须取缔)分析,根据相关法规,提出针对“集中后加工处理”应有政策倾斜、降低成本、提高服务质量及“用来喂猪”时要加强泔水分类、加热喂食等相关注意事项的执行力度等相关对策。  相似文献   
40.
This paper describes the development of a detailed dry deposition model for routine computation of dry deposition velocities of SO2, O3, HNO3 and fine particle SO42− across much of North America. Four different dry deposition/surface exchange sub-models have been combined with the current Canadian weather forecast model (Global Environmental Multiscale model) with a 3 h time resolution and a horizontal spatial resolution of 35 km. The present model uses the US Geological Survey North American Land Cover Characteristics data to obtain fourteen different land use and five seasonal categories. The four sub-models used are a multi-layer model for gaseous species over taller canopy land-use types, a big-leaf model for gaseous species over lower canopies (including bare soil and water) and for HNO3 under all surface types and, two different models for SO42−, one for tall canopies and the other for short canopies. All necessary parameters for each sub-model, chemical species, land-use and seasonal categories have been selected from available data libraries or from the values reported in the literature. The purpose for developing this model (referred to as the Routine Deposition Model (RDM)), when coupled with air concentration data, is to provide estimates of seasonal dry deposition, which can be combined with wet deposition to produce total deposition estimates. Model theory is discussed in this paper and model sensitivity tests and results will be presented in a companion paper.  相似文献   
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