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621.
以粉煤灰为主要原料制备了免烧结粉煤灰陶粒,并将其作为曝气生物滤池(BAF)的填料用于深度处理乙烯化工厂二级生化出水。实验结果表明,在平均进水COD为54.62mg/L、平均SS为33.93mg/L、平均ρ(NH3-N)为1.33mg/L的条件下,自制免烧结粉煤灰陶粒BAF平均COD去除率为57.14%,平均SS去除率为68.64%,平均NH3-N去除率为74.89%,均略高于普通商业陶粒BAF。自制免烧结粉煤灰陶粒BAF最佳反冲洗周期为2d,并具有反冲洗耗水量小、反冲洗效果好的优势。 相似文献
622.
建立了气相色谱(氢火焰离子化检测器)检测乙二醇生产废水中乙二醇、二乙二醇、三乙二醇含量的新方法。该方法采用HP-FFAP型毛细管色谱柱,优化的色谱条件为:进样口温度230℃,初始柱温50℃,载气流量1.0mL/min,分流比1∶1。在质量浓度为1.0~150.0mg/L范围内,废水中各组分色谱峰面积与浓度呈良好的线性关系,相关系数均在0.9989~0.9996之间;相对标准偏差均小于2.0%;乙二醇、二乙二醇、三乙二醇的最低检出限分别为0.63,0.21,0.25mg/L,加标回收率为97.72%~103.52%。 相似文献
623.
624.
餐厨垃圾生产柴油中产生酸化油渣固废(AR)。采用红外光谱(FTIR)法对AR进行分析,认为AR具有较好的阻燃成炭性能。将AR与多聚磷酸铵/三聚氰胺/季戊四醇(APP/MEL/PER)膨胀阻燃体系(IFR)复配,协效阻燃环氧树脂(EP),用极限氧指数法(LOI)、垂直燃烧法(UL94)对其阻燃性能进行了检测,并通过对燃烧残渣的分析讨论了阻燃机理。结果表明,当APP/MEL/PER/AR质量分数为25%,其中AR的质量分数为2%~6%时,阻燃EP的LOI达到30%,具有良好的阻燃性能,并降低了阻燃剂及阻燃材料总体成本。研究成果对餐厨垃圾能源化起到积极推动作用。 相似文献
625.
Box-Behnken响应曲面法优化高聚复配絮凝剂制备条件 总被引:2,自引:0,他引:2
利用活性硅酸和聚合硫酸铁制备聚合硅酸硫酸铁,再采用二甲基二烯丙基氯化铵对其进行复配改性制备高聚复配絮凝剂。在单因素实验的基础上,以絮凝剂脱As性能为评价指标,采用Box-Behnken响应曲面法考察了Fe∶Si、改性剂量、改性温度对高聚复配絮凝剂制备的单独作用及交互影响作用,并建立了剩余c(As)的数学模型。结果显示,自变量对响应值的影响次序为:Fe∶Si改性温度改性剂量,改性剂量与改性温度及改性剂量与Fe∶Si交互影响显著;数学模型拟合度程度良好,模型显著,模型预测处理后最佳剩余c(As)=18.82μg/L,最佳工艺条件为Fe∶Si=2.1∶1,改性温度=79℃,改性剂量=0.56%(PFSS溶液质量),验证实验结果为剩余c(As)=19.21μg/L,预测值与测定值偏差率为2.07%。 相似文献
626.
The theory of Markov Chain is used scientifically to describe the transfer/transformation of phenanthrene in Lanzhou Reach of Yellow River. In Markov Model (MM), the states of phenanthrene in Lanzhou Reach are divided into six different states, namely being degraded, leaving the system with the addvective flow, being in air, being in water, being adsorbed on suspending substances (SS), and being in bottom sediment (BS). The MM is simulated by using Matlab6.5 to reveal the temporal changes and environmental fate of phenanthrene in Lanzhou Reach. It is shown that the environmental system will be steady in 30,000-35,000 h, the final distributions of phenanthrene in air, water, SS, and BS are 23,033 kg, 1961 kg, 800 kg, and 2824 kg respectively, with the corresponding percent of 80%, 7%, 3%, and 10%.The results of MM are approximate to the results of Fugacity Model (FM), so Markov Chain can be used to evaluate the environmental fate of pollutants in multimedia environment. The outputs of MM include the following aspects: (1) The residual time of pollutant in different environmental media and the transiting time of pollutant between different environmental media; (2) The response time of the environmental system; (3) The total mass of pollutant transferred or degraded during a given time interval; (4) The time needed for the environmental system to be steady and the final steady distributions of pollutant in the environmental system. 相似文献
627.
Photocatalytic degradation of methyl orange in aqueous suspension of mesoporous titania nanoparticles 总被引:2,自引:0,他引:2
The photodegradation of methyl orange (MO) was investigated in aqueous suspension containing titania nanoparticles with mesostructures (m-TiO(2)) under UV irradiation. The experimental results show that 98% MO can be mineralized in the 1.0 g l(-1) m-TiO(2) suspension (pH 2.0) after 45 min illumination. Particular attention was devoted to the identification and the transformation of the fragments retaining the chromophoric group. The photodegradation mechanism of the quinonoid MO mainly involves three intermedial processes: demethylation, methylation and hydroxylation. Among those processes, demethylation is more favorable than the hydroxylation, but the hydroxylation results in the largest number of intermediates. The degradation pathway of quinonoid MO under the optimal conditions is also proposed. 相似文献
628.
Removal of phenolic estrogen pollutants from different sources of water using molecularly imprinted polymeric microspheres 总被引:4,自引:0,他引:4
Lin Y Shi Y Jiang M Jin Y Peng Y Lu B Dai K 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):483-491
The efficiency and effects of using Bisphenol A-molecularly imprinted polymeric microspheres (MIPMs) to remove phenolic estrogens from different sources of water were evaluated. MIPMs prepared by precipitation polymerization removed a group of phenolic estrogens from different kinds of water selectively and effectively. The highest removal efficiency was observed at pH=5. Fifty millimoles per litre ions or 10mg/L humid acid improved removal efficiency. MIPMs were more suitable to remove trace estrogens in large volume than high concentration of estrogens in small volume. The removal efficiency of spiked tap water, lake water and river water were better than that of distilled water. Hundred milligrams of MIPMs had higher removal selectivity and efficiency than those of 100mg or 300mg activated carbons. Moreover, MIPMs can be re-used for at least 30 times without losing any removal efficiency. MIPMs provided a selective, simple, reliable and practicable solution to remove trace phenolic estrogens from different sources of water. 相似文献
629.
630.
Overexpressing GSH1 and AsPCS1 simultaneously increases the tolerance and accumulation of cadmium and arsenic in Arabidopsis thaliana 总被引:1,自引:0,他引:1
The goal of this study was to develop transgenic plants with increased tolerance for and accumulation of heavy metals and metalloids from soil by simultaneous overexpression of AsPCS1 and GSH1 (derived from garlic and baker's yeast) in Arabidopsis thaliana. Phytochelatins (PCs) and glutathione (GSH) are the main binding peptides involved in chelating heavy metal ions in plants and other living organisms. Single-gene transgenic lines had higher tolerance to and accumulated more Cd and As than wild-type. Compared to single-gene transgenic lines, dual-gene transformants exhibited significantly higher tolerance to and accumulated more Cd and As. One of the dual-gene transgenic lines, PG1, accumulated twice the amount of Cd as single-gene transgenic lines. Simultaneous overexpression of AsPCS1 and GSH1 led to elevated total PC production in transgenic Arabidopsis. These results indicate that such a stacking of modified genes is capable of increasing Cd and As tolerance and accumulation in transgenic lines, and represents a highly promising new tool for use in phytoremediation efforts. 相似文献