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91.
Experimental research on emission and removal of dioxins in flue gas from a co-combustion of MSW and coal incinerator 总被引:1,自引:0,他引:1
This paper describes the experimental study of dioxins removal from flue gas from a co-combustion municipal solid waste and coal incinerator by means of a fluidized absorption tower and a fabric filter. A test rig has been set up. The flow rate of flue gas of the test rig is 150-2000 m3/h. The system was composed of a humidification and cooling system, an absorption tower, a demister, a slurry make-up tank, a desilter, a fabric filter and a measurement system. The total height of the absorption tower was 6.5m, and the diameter of the reactor pool was 1.2 m. When the absorbent was 1% limestone slurry, the recirculation ratio was 3, the jet rate was 5-15 m/s and the submerged depth of the bubbling pipe under the slurry was 0.14 m, the removal efficiency for dioxins was 99.35%. The concentration of dioxins in the treated flue gas was 0.1573 x 10(-13)kg/Nm3 and the concentration of oxygen was 11%. This concentration is comparable to the emission standards of other developed countries. 相似文献
92.
93.
复合污染状态下尾矿区有害化学品的迁移研究 总被引:4,自引:0,他引:4
用混合尾矿浆及尾矿渣淋溶柱,研究选矿药剂在尾矿渣及尾矿废水中的静态分布及其淋溶作用,结果表明:①选矿药剂对整个尾矿区都污染,即使是水溶性好的药剂,它们在尾矿渣中的静态分布也占有相当的比例,油溶性好的药剂多存在于尾矿渣中,尾矿污染为多种药剂的复合污染,各种药剂在尾矿渣及尾矿废水中的总浓度成倍加大;②用尾矿渣淋溶柱测得单一药剂的淋溶值:25号黑药>MIBC> CN->二号油>乙基黄药>丁基黄药>Y-89黄药.但多种药剂复合污染时,药剂的淋溶距离明显加大,其中CN-和Y-89黄药加大近一倍.复合药剂污染加大药剂的残留期,也加大它们向地下水及其它水源迁移的几率. 相似文献
94.
流动注射-氢化物发生-原子荧光光谱法测定土壤中铅 总被引:1,自引:0,他引:1
采用流动注射-氢化物发生-原子荧光光谱法测定土壤中的铅,工作曲线线性关系良好,检出限为0.25 mg/kg,相对标准偏差<3.5%,加标回收率为93.0%~105%.该方法简便快速,测定结果准确可靠. 相似文献
95.
黄土高原能源富集区是我国重要的能源基地和粮食主产区,其水资源匮乏使区域水—能源—粮食纽带系统可持续发展面临严峻挑战。为研究黄土高原能源富集区能源、粮食与水资源之间协调发展状况,本研究以水—能源—粮食纽带系统安全为核心,通过构建水—能源—粮食纽带系统安全评价指标体系,采用TOPSIS模型和耦合协调度模型,分析了典型案例地榆林市及榆阳区水—能源—粮食纽带系统安全水平及其耦合协调关联特征。结果表明:从水—能源—粮食纽带系统耦合协调关系来看,榆林市各区县水—能源—粮食纽带系统耦合度整体较高且近年来呈现缓慢下降趋势,耦合协调度呈现“北高南低”格局且近年来表现出轻微下降趋势。从榆阳区层面来看,榆阳区水—能源—粮食纽带系统耦合度较高,耦合协调度呈现由中度协调向优质协调发展态势,水资源系统制约水—能源—粮食纽带系统安全发展,能源子系统波动性较强。为协调能源富集区水—能源—粮食纽带系统可持续发展,政府应健全跨部门协调机制,因地制宜、合理规划产业布局,同时构建节约高效的资源管理体系,提升资源使用效率。 相似文献
96.
Field released transgenic papaya effect on soil microbial communities and enzyme activities 总被引:5,自引:1,他引:4
WEI Xiang-dong ZOU Hui-ling CHU Lee-min LIAO Bin YE Chang-min LAN Chong-yu 《环境科学学报(英文版)》2006,18(4):734-740
Soil properties, microbial communities and enzyme activities were studied in soil amended with replicase (RP)-transgenic or non-transgenic papaya under field conditions. Compared with non-transgenic papaya, significant differences (P〈0.05) were observed in total nitrogen in soils grown with transgenic papaya. There were also significant differences (P〈0.05) in the total number of colony forming units (CFUs) of bacteria, actinomycetes and fungi between soils amended with RP-transgenic plants and non-transgenic plants. Compared with non-transgenic papaya, the total CFUs of bacteria, actinomycetes and fungi in soil with transgenic papaya increased by 0.43-1.1, 0.21-0.80 and 0.46-0.73 times respectively. Significantly higher (P〈0.05) CFUs of bacteria, actinomycetes and fungi resistant to kanamycin (Km) were obtained in soils with RP-transgenic papaya than those with non-transgenic papaya in all concentrations of Km. Higher resistance quotients for Km' (kanamycin resistant) bacteria, actinomycetes and fungi were found in soil planted with RP-transgenic papaya, and the resistance quotients for Km' bacteria, actinomycetes and fungi in soils with transgenic papaya increased 1.6-4.46, 0.63-2.5 and 0.75-2.30 times. RP-transgenic papaya and non-transgenic papaya produced significantly different enzyme activities in arylsulfatase (5.4-5.9x), polyphenol oxidase (0.7-1.4x), invertase (0.5-0.79x), cellulase (0.23-0.35x) and phosphodiesterase (0.16-0.2x). The former three soil enzymes appeared to be more sensitive to the transgenic papaya than the others, and could be useful parameters in assessing the effects of transgenic papaya. Transgenic papaya could alter soil chemical properties, enzyme activities and microbial communities. 相似文献
97.
绿色技术创新作为区域技术创新体系的重要组成部分,是维持区域发展可持续性、增强区域竞争优势的重要驱动力.基于区域一体化的研究视角,通过采集长三角绿色技术专利合作及绿色技术转移数据,运用Gephi复杂网络分析方法,对长三角绿色技术创新网络进行结构分析.结果 表明:(1)长三角绿色技术创新网络发育程度较低,大量城市在绿色技术创新网络中较边缘化;(2)绿色技术创新依赖创新主体间知识互动,地理邻近促进了创新合作行为的产生和知识的扩散;(3)长三角绿色技术创新网络"强-强联系"与"核心-边缘"结构特征明显,绿色技术专利合作网络呈现"一超多强"的多中心格局,绿色技术转让网络呈现单中心格局;(4)区域一体化下,长三角绿色技术创新网络兼具邻近性和等级性特征,不同类型城市参与创新网络应有差异;进而,提出长三角绿色技术创新网络优化策略.创新点在于:建立了区域一体化与技术创新网络的关联,探讨了绿色技术创新的空间组织形式,强调了地理邻近对于绿色技术创新网络的重要性. 相似文献
98.
99.
Cuong Van Hoang Tuyen Quang Tran Yen Hai Thi Nguyen Lan Thanh Nguyen 《Natural resources forum》2020,44(4):311-333
Using secondary data from a socio-economic quantitative household survey of the North Central region of Vietnam, the main aim of our study is to analyze the causal effect of forest resources on household income and poverty. Based on the observed characteristics of a forest-based livelihood and forest-related activities, we use a propensity score matching (PSM) method to control for potential bias arising from self-selection. The PSM results indicate that households with a forest-based livelihood had a higher level of income and lower poverty rates than did those without. Interestingly, our findings confirm that a forest-based livelihood offers much higher income than any other type of livelihood adopted by local households. Also, the poverty rate among households with a forest-based livelihood is lower than those earning non-labor income or engaged in wage/crop and crop livelihoods. Among households and provinces, we find varying opportunities deriving from forest resources, suggesting that there are potential barriers hindering local households from pursuing a forest livelihood or participating in some forest activities. Therefore, government policy and regulations on forest management should focus on improving the access of households to forest resources, while enhancing the sustainability of these resources. 相似文献
100.
以废铅酸蓄电池中铅膏为研究对象,开展了用NH_4HCO_3为脱硫剂对铅膏进行脱硫转化的实验研究。通过分析反应过程中PbSO_4转化率随时间的变化关系,考察了搅拌速度、反应温度及NH_4HCO_3浓度对铅膏脱硫转化的影响;利用固液多相反应的收缩核模型,分析了反应的动力学过程,并计算了反应的表观活化能及表观反应级数。结果表明:在实验选取的条件范围内,提高反应温度、增大NH_4HCO_3浓度及加快搅拌速度均可以促进铅膏的脱硫转化;表观活化能为9.7 kJ·mol~(-1),表观反应级数为0.71,反应过程受内扩散步骤控制。研究结果可为铅膏铵法预脱硫技术能高效、低耗的应用提供参考。 相似文献