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1.
燃煤电厂海水烟气脱硫工艺原理初探   总被引:12,自引:1,他引:11  
董学德  李绍箕 《环境工程》1997,15(4):23-26,56
海水烟气脱硫工艺是利用天然的纯海水(燃煤电厂可直接利用电厂的冷却循环水)作为烟气中SO2的吸收剂,无需其它任何添加剂,也不产生任何废弃物,具有技术成熟、工艺简单、系统运行可靠、脱硫效率高(理论脱硫效率可达98%)和投资运行费用低等特点,目前在一些国家和地区已得到日益广泛的应用。本文是在部分模拟试验的基础上,对海水烟气脱硫工艺进行了简单的阐述。  相似文献   
2.
论土地持续利用   总被引:33,自引:0,他引:33  
在世界上有两种可持续发展思路,一种是西方发达国家的重保护的可持续发展思路;一种是以发展为前提,保护自然资源的可持续发展思路。土地持续利用的思想是在可持续发展的进程中不断发展的。我国要保证土地持续利用,满足未来对食粮和建设的需求,应建立起同土地持续利用相适应的土地持续利用制度和土地持续利用机制  相似文献   
3.
Environment, Development and Sustainability - The ecological compensation mechanism is regarded as the direction for the future management of the ecological environment of the river basin, which...  相似文献   
4.
Environment, Development and Sustainability - Ecological welfare performance is a measure of the relationship between input ecological resources and output welfare, and it reflects the sustainable...  相似文献   
5.
Carbon–silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal environment.The physicochemical properties of the materials were characterized by nitrogen physical adsorption(BET),scanning electron microscopy(SEM),and thermogravimetric(TG),and the adsorption properties of various organic waste gases were investigated.The results showed that microporous carbon materials were introduced successfully into the silica gel channels,thus showing the high adsorption capacity of activated carbon in high humidity organic waste gas,and the high stability and mechanical strength of the silica gel.The dynamic adsorption behavior confirmed that the carbon–silica material had excellent adsorption capacity for different volatile organic compounds(VOCs).Furthermore,the carbon–silica material exhibited excellent desorption characteristics:adsorbed toluene was completely desorbed at 150℃,thereby showing superior regeneration characteristics.Both features were attributed to the formation of hierarchical pores.  相似文献   
6.
Ground-level ozone (O3) has become a critical pollutant impeding air quality improvement in Yangtze River Delta region of China. In this study, we present O3 pollution characteristics based on one-year online measurements during 2016 at an urban site in Nanjing, Jiangsu Province. Then, the sensitivity of O3 to its precursors during 2 O3 pollution episodes in August was analyzed using a box model based on observation (OBM). The relative incremental reactivity (RIR) of hydrocarbons was larger than other precursors, suggesting that hydrocarbons played the dominant role in O3 formation. The RIR values for NOX ranged from –0.41%/% to 0.19%/%. The O3 sensitivity was also analyzed based on relationship of simulated O3 production rates with reductions of VOC and NOX derived from scenario analyses. Simulation results illustrate that O3 formation was between VOCs-limited and transition regime. Xylenes and light alkenes were found to be key species in O3 formation according to RIR values, and their sources were determined using the Positive Matrix Factorization (PMF) model. Paints and solvent use was the largest contributor to xylenes (54%), while petrochemical industry was the most important source to propene (82%). Discussions on VOCs and NOX reduction schemes suggest that the 5% O3 control goal can be achieved by reducing VOCs by 20%. To obtain 10% O3 control goal, VOCs need to be reduced by 30% with VOCs/NOX larger than 3:1.  相似文献   
7.
Molecular level characterization of dissolved organic sulfur (DOS) by electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) is necessary for further understanding of the role of DOS in the environment. Here, ESI spray solvent, a key parameter for ion production during ESI process, was investigated for its effect on the molecular characterization of DOS by ESI-FTICR MS. 100% MeOH as spray solvent was found for the first time to remarkably enhance the ionization efficiency of the majority of CHOS-molecules in NOM, which facilitated a total of 1473 CHOS-molecular formulas with one sulfur atom to be detected. The number of CHOS-molecular formulas obtained using 100%MeOH as spray solvent increased notably over 740 in comparison with those using 50% MeOH aqueous solution (731) or 50% ACN aqueous solution (653). Moreover, due to the enhancement of ionization efficiency of DOS during ESI processes, the tandem mass spectra of the NOM CHOS-molecules could be easily obtained using 100% MeOH as spray solvent, which were hardly obtained using 50% MeOH aqueous solution as spray solvent. The results of the tandem mass spectra suggested the first discovery of organosulfates or sulfonic acids in Suwannee River NOM sample. A simple method based on 100% MeOH as ESI spray solvent for advanced molecular characterization of DOS by ESI-FTICR MS was proposed and applied, and the results revealed more molecular information of DOS in sea DOM samples.  相似文献   
8.
三江源植被碳利用率动态变化及其对气候响应   总被引:2,自引:0,他引:2  
本文基于MODIS GPP/NPP数据估算了三江源植被碳利用率(CUE),结合气象数据和高程数据采用一元线性回归和相关分析法,探讨了2001~2017年三江源植被CUE的时空变化特征及植被CUE对气温、降水量和蒸散量变化的响应.结果表明:(1)三江源植被CUE年内3~10月表现为先增加后降低的变化趋势,其中6月植被CUE最高.(2)三江源年植被碳利用率位于0.73~1,平均水平为0.85;植被CUE空间上呈现北高南低,西高东低的分布特征.(3)整体上,三江源4~10月植被碳利用率与同期气温、降水量和蒸散量分别呈现正相关、负相关和负相关关系,降水量是影响三江源植被CUE变化的主要影响因素,气温为次要因素,蒸散量影响程度最小.  相似文献   
9.
为了解烟花爆竹燃放对保定市大气污染物和PM2.5中水溶性离子及有机碳(OC)、元素碳(EC)浓度的影响,对保定市春节期间大气污染物和颗粒物组分的浓度特征进行了分析,并评估了烟花爆竹的贡献.结果表明: 2019年春节期间烟花爆竹集中燃放期PM2.5、PM10、SO2、NO2、CO平均浓度比非集中燃放期分别增加了1.3、1.0、1.1、0.4、0.02倍;保定市春节期间禁燃措施施行后,除夕、初一2d污染物平均浓度、最高浓度和高浓度持续时间均明显下降,集中燃放期烟花爆竹燃放对PM2.5、PM10和SO2浓度贡献量从50%左右(2018年、2017年)下降至30%左右(2019年),其中SO2贡献量下降幅度超过PM2.5和PM10;组分分析表明,接待中心站点(主城区)、涿州站点(区县建成区)烟花爆竹燃放期K+、Mg2+、Cl-浓度在水溶性离子中的总占比分别为39.3%、51.1%,比非燃放期的占比显著上升;烟花爆竹燃放对PM2.5中K+、Mg2+、Cl-浓度贡献率在50%以上,其中对K+贡献占比高达89.0%,涿州站点SO42-、K+、Mg2+、Cl-的贡献量分别是接待中心站点的2.2、2.1、1.9、1.8倍,燃放期硫氧化率(SOR)、氮氧化率(NOR)相比于非燃放期均有一定程度的升高;集中燃放期OC、EC浓度较非集中燃放期分别升高了2.5、2.1倍,烟花爆竹燃放对OC影响大于EC.  相似文献   
10.
Mitigation and Adaptation Strategies for Global Change - Electric vehicles (EVs) play a crucial role in addressing climate change and urban air quality concerns. China has emerged as the global...  相似文献   
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