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601.
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Temporal variability of iron concentrations and fractions in wetland waters in
Sanjiang Plain, Northeast China 总被引:1,自引:0,他引:1
Chemical forms, reactivities and transformation of iron fractions in marshy waters were investigated with cross-flow filtration technique to study the iron environmental behavior. Iron fractions were divided into four parts: acid-labile iron (pre-acidification of unfiltered marshy water samples, 0.7 μm), high-molecular-weight iron (0.7-0.05 μm), medium-molecular-weight iron (0.05-0.01 μm), and low-molecular-weight iron ( 0.01 μm). The cross-flow filtration suggested that iron primarily exist in both the 0.7 μm and 0.01 μm size fractions in marshy waters. Rainfall is the key for rain-fed wetland to determine fate of iron by changing the aquatic biochemical conditions. By monitoring the variation of iron concentrations and fractions over three years, it was found that dissolved iron and acid-labile iron concentrations exhibit a large variation extent under different annual rainfalls from 2006 to 2008. The seasonal variation for iron species proved that the surface temperature could control some conversion reactions of iron in marshy waters. Low- molecular-weight iron would convert to acid-labile iron gradually with temperature decreasing. The photochemical reactions of iron fractions, especially low-molecular-weight iron had occurred under solar irradiation. The relative proportion of low-molecular-weight in total dissolved iron ranging from 28.3% to 43.2% were found during the day time, which proved that the observed decreasing concentration of acid lability iron was caused by its degradation to low molecular weight iron. 相似文献
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潘新元 《安全.健康和环境》2007,7(10):22-24
介绍了NID脱硫技术在410 t/h燃煤锅炉与气动脱硫技术在220 t/h水煤浆锅炉上的应用情况,比较分析了两种脱硫装置的运行成本,并提出成本控制建议. 相似文献
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载镁活化天然沸石处理高氟水实验研究 总被引:1,自引:1,他引:0
为了提高沸石对氟的吸附能力,采用氯化镁对活化天然沸石进行改性,分析了除氟剂的性能,确定了除氟剂改性的最佳条件:10%氯化镁溶液,固液比1∶4,pH=7.0,室温以300 r/min的速度振荡改性3h。最佳除氟条件:pH=7.0,室温以300 r/min的速度搅拌反应1.5 h。吸附剂对F-的吸附过程符合Langmuir及Freundlich等温线方程,由D-R模型拟合可知,除氟剂对氟的吸附为物理吸附过程。在最佳反应条件下,水样中氟浓度由2 mg/L降低到0.78 mg/L,符合GB5949-2006《生活饮用水卫生标准》(≤1 mg/L)。 相似文献
608.
Removal of antimony from antimony mine flotation wastewater by
electrocoagulation with aluminum electrodes 总被引:3,自引:0,他引:3
Antimony (Sb) has received increasing environmental concerns due to its potential toxic and carcinogenic properties. In the present
work, the electrocoagulation technique was used to treat the flotation wastewater from a heavy antimony polluted area, and the
mechanism of removing Sb was also investigated. The study focused on the effect of operation parameters such as current density,
initial pH and standing time on the Sb removal efficiency. Antimony concentration of below 1 mg/L in the treated wastewater was
achieved, which meets the emission standards established by State Department of Environmental Protection and State Administration
of China for Quality Supervision and Inspection and Quarantine of China. 相似文献
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本文拟通过对公路建设所造成的对生态环境的影响分析,以进一步提出生态恢复的方法和手段,从而在最大限度上降低因公路建设造成的对内蒙古地区的生态影响。 相似文献