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711.
A method, based on spatial analysis of the different criteria to be taken into consideration for building scenarios of CO2 capture and storage (CCS), has been developed and applied to real case studies in the Hebei province. Totally 88 point sources (42 from power sector, 9 from iron and steel, 18 from cement, 16 from ammonia, and 3 from oil refinery) are estimated and their total emission amounts to 231.7 MtCO2/year with power, iron and steel, cement, ammonia and oil refinery sharing 59.13%, 25.03%, 11.44%, 3.5%, and 0.91%, respectively. Storage opportunities can be found in Hebei province, characterised by a strong tectonic subsidence during the Tertiary, with several kilometres of accumulated clastic sediments. Carbon storage potential for 25 hydrocarbon fields selected from the Huabei complex is estimated as 215 MtCO2 with optimistic assumption that all recovered hydrocarbon could be replaced by an equivalent volume of CO2 at reservoir conditions. Storage potential for aquifers in the Miocene Guantao formation is estimated as 747 MtCO2 if closed aquifer assumed or 371 MtCO2 if open aquifer and single highly permeable horizon assumed. Due to poor knowledge on deep hydrogeology and to pressure increase in aquifer, injecting very high rates requested by the major CO2 sources (>10 MtCO2/year) is the main challenge, therefore piezometry and discharge must be carefully controlled. A source sink matching model using ArcGIS software is designed to find the least-cost pathway and to estimate transport route and cost accounting for the additional costs of pipeline construction due to landform and land use. Source sink matching results show that only 15–25% of the emissions estimated for the 88 sources can be sequestrated into the hydrocarbon fields and the aquifers if assuming sinks should be able to accommodate at least 15 years of the emissions of a given source.  相似文献   
712.
Yang F  Jin S  Meng D  Xu Y 《Chemosphere》2010,81(8):1000-1005
A solid phase extraction (SPE) method using pyrenebutyric acid-bonded silica (PYB) as sorbent was developed to determine 23 polychlorinated biphenyls (PCBs) in sewage water by gas chromatography-mass spectrometry (GC-MS). Factors were optimized in SPE procedures including elution solvent, pH, and cartridge burden. The recoveries of 23 PCB congeners were 69.44-111.91% under optimized conditions. Comparisons were also conducted among PYB-SPE, C(18)-SPE and United States Environmental Protection Agency 608 (USEPA608) methods in the analysis of PCBs in sewage water samples. The results showed that the performance of PYB-SPE method was similar with USEPA608 method and better than C(18)-SPE method. Both PYB-SPE and USEPA608 methods were then employed to analyze PCBs in real spiked sewage water samples. The recoveries of PCB congeners determined by PYB-SPE method ranged from 70.6% to 92.4% in real spiked sewage water samples which were identified to be in accordance with USEPA608 method. Limits of detection (LOD) were in the range of 0.06-0.22ngL(-1) for PCB congeners. The optimized PYB-SPE method was successfully applied to the determination of PCBs in sewage water samples.  相似文献   
713.
A set of toxic metals, i.e. As, Hg, Pb, Cd, Cu, Zn, Ni and Cr, in urban and suburban SDSs were investigated comparatively in the biggest metropolitan area of China, Shanghai. Results showed that all of the metals except As were accumulated greatly, much higher than background values. Geo-accumulation index indicated that metal contamination in urban SDSs was generally heavier than that in suburban SDSs. Potential ecological risk index demonstrated that overall risks caused by metals were considerable. Cd contributed 52% to the overall risk. Multivariate statistical analysis revealed that in urban SDSs, Zn, Ni, Cd, Pb, Cu and Cr were related to traffic and industry; coal combustion led to elevated levels of Hg; soil parent materials controlled As contents. In suburban SDSs, Pb, Cu, As and Cd largely originated from traffic pollution; Zn, Ni and Cr were associated with industrial contaminants; Hg was mainly from domestic solid waste.  相似文献   
714.

Background, aim, and scope  

Current Australian legislation permits the beneficial application of grease trap waste (GTW) to agricultural soil, viewing it as a beneficial source of organic matter and soil conditioner containing no/low amounts of metals or pathogenic organisms. However, little is known about the influence of GTW on soil bacterial community. A field experiment was established at Menangle in south western Sydney in Australia to quantitatively assess the impacts of different types (GTW CO and GTW CL) and amounts of GTW application on the soil bacterial community and diversity. Furthermore, a municipal solid waste (MSW) compost was simultaneously examined to compare against the other organic wastes. Knowledge about the shifts in microbial community structure and diversity following the applications of organic wastes could help to evaluate the ecological consequences on the soil and thus to develop sound regulatory guidelines for the beneficial reuse of organic wastes in agricultural lands.  相似文献   
715.

Background, aim, and scope  

Persistent organic pollutants and heavy metals can cause diseases in women, however, the relationships of these pollutants and uterine leiomyomas (UL), which are non-cancerous tumors of the uterus, are unclear. This study focused on the quantification of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), and heavy metals in subcutaneous and visceral fat obtained from patients with UL and in subcutaneous fat of a control group of women without UL to determine if there were any correlations between concentrations of persistent organic pollutants (POPs) and heavy metals and the incidence of UL.  相似文献   
716.
Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC = 8.7 ± 4.5 μg/m3, EC = 2.5 ± 1.9 μg/m3) among the three sites, and Jianfeng Mountains in Hainan Island (OC = 5.8 ± 2.6 μg/m3, EC = 0.8 ± 0.4 μg/m3) and Tengchong mountain over the east edge of the Tibetan Plateau (OC = 4.8 ± 4.0 μg/m3, EC = 0.5 ± 0.4 μg/m3) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.  相似文献   
717.

Purpose

The environmental issues caused by the municipal solid waste disposal are becoming a worldwide concern.

Methods

We studied the situations both domestically and abroad by the strategic environmental assessment (SEA) approach and also conducted comprehensive evaluations of garbage disposal in Changchun City.

Results

On the basis of this study, we found that SEA is of great importance in the municipal solid waste disposal. Moreover, with the rapid socioeconomic development of Changchun City, municipal solid waste production increases on an annual basis, and thus, good waste management planning is of great significance.

Conclusions

Considering the situation of the economic development of Changchun City, garbage disposal was handled mainly in the major sanitary landfills with appropriate use of incineration technology. This plan is environmentally friendly at a relatively high degree and has met the requirements of minimum investment. It also takes into account the requirements of the development of incineration technology. Regarding environmental pollution in terms of groundwater pollution and atmospheric pollution, this plan is a feasible one by meeting various requirements with low environmental impact among the three plans discussed in this study.  相似文献   
718.
将预先经酸处理的铝钛硅(ATS)多相陶瓷片先后负载Al0.2Ti0.6Zr0.2O1.9复合氧化物与CeO2活性组分,制得新型CeO2/Al0.2Ti0.6Zr0.2O1.9/ATS复合脱硝催化剂。运用X射线衍射(XRD)、扫描电镜(SEM)手段对该催化剂进行表征,研究催化剂的晶相、微观形貌。评价了催化剂的脱硝活性,研究了H2O和SO2对其脱硝活性的影响。实验结果表明,CeO2/Al0.2Ti0.6Zr0.2O1.9/ATS具有良好的脱硝活性,高活性温度窗口在100~350℃,当反应温度为250℃时,NO的转化率达98.49%。SO2和H2O在一定程度抑制该催化剂的低温脱硝活性,但随着温度的升高,其脱硝活性逐渐恢复。催化剂中活性组分CeO2具有储硫作用,当有SO2存在时,活性温度窗口向高温区偏移了100℃,在250~400℃时,H2O的存在反而提高了催化剂的脱硝活性。  相似文献   
719.
采用浸渍法制备了CuO/BiVO4光催化剂,通过X射线衍射(XRD)、热重/差示扫描量热(TG/DSC)和傅立叶红外光谱(FTIR)对其进行了表征,并在可见光照射下考察了其光催化氧化亚甲基蓝(MB)的动力学特性。结果表明,Cu的掺杂并未改变BiVO4的晶型结构;Cu(NO3)2/BiVO4在热处理(30~300℃)过程中,NO3-已经完全分解,Cu最终以CuO的形式存在于CuO/BiVO4光催化剂体系中;掺杂不同量Cu的CuO/BiVO4中的Cu2+/Bi+(摩尔比)实测值与理论值相近,该系列光催化剂的合成过程具有较高的可信度;在可见光照射下,CuO/BiVO4光催化降解MB反应符合表观一级反应动力学特征;当Cu2+/Bi+为0.050时,反应动力学速率常数(k)达到最高值(0.4334h-1),此时的k比单体BiVO4作用下的提高了1.04倍;由于异质结的存在,CuO/BiVO4与单体BiVO4相比,电子和空穴的利用率大大增加,使得CuO/BiVO4的光催化活性较单体BiVO4有了大幅度提高。  相似文献   
720.
中性红在柚子皮上的吸附机制研究   总被引:2,自引:0,他引:2  
采用柚子皮作为生物吸附材料吸附去除中性红。研究了中性红的初始浓度、吸附时间及反应温度对吸附效果的影响。结果表明,当中性红溶液从100 mg/L升高到250 mg/L时,反应95 min后,柚子皮对中性红的吸附量从16.80 mg/g增加到40.00mg/g。中性红在柚子皮上的吸附在60 min内基本上可以达到平衡,且柚子皮对中性红的吸附过程为放热过程;二级吸附动力学方程能更好地描述中性红在柚子皮上的吸附行为;中性红在柚子皮孔隙中的扩散不是唯一的吸附速率控制步骤,这个吸附过程可能受多个步骤共同控制;柚子皮对中性红的吸附是自发吸附,Langmuir、Freundlich和Temkin吸附等温式能很好地拟合柚子皮对中性红的吸附过程,拟合相关系数分别达到了0.991 8、0.993 4、0.989 0。  相似文献   
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