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81.
中国危险废物和医疗废物焚烧处置行业二(口恶)排放水平研究 总被引:1,自引:0,他引:1
通过调研全国危险废物和医疗废物焚烧处置设施,对包含二噁英排放水平的设施按处置对象、炉型和处理量分类,并作系统分析和研究.结果表明现有危险废物焚烧设施烟气中二噁英的浓度比医疗废物低,达标率为74.19%;危险废物选用回转窑处置效果较好,达标率为66.67%;而医疗废物选用回转窑或热解炉,要综合考虑处置规模、生产成本和二英排放总量等因素;危险废物介于10~30 t·d-1和医疗废物介于10~20 t·d-1的处置设施要尤其注意二噁英的排放问题;医疗废物焚烧飞灰中二噁英的均值浓度为危险废物6倍以上,仅有16.67%满足填埋要求.二者烟气中二英的浓度分布以1,2,3,4,6,7,8-HpCDF、2,3,7,8-TCDF和OCDD为主. 相似文献
82.
Comparison of quartz sand, anthracite, shale and biological ceramsite for adsorptive removal of phosphorus from aqueous solution 总被引:1,自引:0,他引:1
The choice of substrates with high phosphorus adsorption capacity is vital for sustainable phosphorus removal from waste water in constructed wetlands. In this study, four substrates were used: quartz sand, anthracite, shale and biological ceramsite. These substrate samples were characterized by X- ray diffractometry and scanning electron microscopy studies for their mineral components (chemical components) and surface characteristics. The dynamic experimental results revealed the following ranking order for total phosphorus (TP) removal efficiency: anthracite 〉 biological ceramsite 〉 shale 〉 quartz sand. The adsorptive removal capacities for TP using anthracite, biological ceramsite, shale and quartz sand were 85.87, 81.44, 59.65, and 55.98 mg/kg, respectively. Phosphorus desorption was also studied to analyze the substrates' adsorption efficiency in wastewater treatment as well as the substrates' ability to be reused for treatment. It was noted that the removal performance for the different forms of phosphorus was dependent on the nature of the substrate and the adsorption mechanism. A comparative analysis showed that the removal of particulate phosphorus was much easier using shale. Whereas anthracite had the highest soluble reactive phosphorus (SRP) adsorptive capacity, biological ceramsite had the highest dissolved organic phosphorus (DOP) removal capacity. Phosphorus removal by shale and biological ceramsite was mainly through chemical adsorption, precipitation or biological adsorption. On the other hand, phosphorus removal through physical adsorption (electrostatic attraction or ion exchange) was dominant in anthracite and quartz sand. 相似文献
83.
An organo-montmorillonite-supported nanoscale zero-valent iron material(M-NZVI) was synthesized to degrade decabromodiphenyl ether(BDE-209). The results showed that nanoscale zero-valent iron had good dispersion on organo-montmorillonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30–90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased. 相似文献
84.
Catalytic bubble-free hydrogenation reduction of azo dye by porous membranes loaded with palladium (Pd) nanoparticles was studied for the first time. The effects of Pd loading, dye concentration and reuse repetitions of membranes were investigated. In reduction, the dye concentration decreased whereas the pH rose gradually. An optimal Pd loading was found. The catalytic membranes were able to be reused more than 3 times. 相似文献
85.
Carbonyl emissions from heavy-duty diesel vehicle exhaust in China and the contribution to ozone formation potential 总被引:6,自引:0,他引:6
Fifteen heavy-duty diesel vehicles were tested on chassis dynamometer by using typical heavy duty driving cycle and fuel economy cycle. The air from the exhaust was sampled by 2,4- dinitrophenyhydrazine cartridge and 23 carbonyl compounds were analyzed by high performance liquid chromatography. The average emission factor of carbonyls was 97.2 mg/km, higher than that of light-duty diesel vehicles and gasoline-powered vehicles. Formaldehyde, acetaldehyde, acetone and propionaidehyde were the species with the highest emission factors. Main influencing factors for carbonyl emissions were vehicle type, average speed and regulated emission standard, and the impact of vehicle loading was not evident in this study. National emission of carbonyls from diesel vehicles exhaust was calculated for China, 2011, based on both vehicle miles traveled and fuel consumption. Carbonyl emission of diesel vehicle was estimated to be 45.8 Gg, and was comparable to gasolinepowered vehicles (58.4 Gg). The emissions of formaldehyde, acetaldehyde and acetone were 12.6, 6.9, 3.8 Gg, respectively. The ozone formation potential of carbonyls from diesel vehicles exhaust was 537 mg O3/km, higher than 497 mg O3/km of none-methane hydrocarbons emitted from diesel vehicles. 相似文献
86.
采用3种电子受体(硝氮、亚硝氮、氧),在SBR反应器中分别驯化了具有稳定除磷能力的聚磷污泥。对比研究了不同聚磷污泥胞外聚合物(EPS)的组分与含量,结合三维荧光光谱对EPS中有机物质进行分析。研究表明,以硝氮、亚硝氮为电子受体的聚磷污泥EPS平均浓度较为接近,分别为115.6mg/gVSS、133.5 mg/gVSS,由厌氧段至缺氧段,EPS总浓度有所下降。以氧为电子受体聚磷污泥的EPS平均浓度相对较高,为194.5 mg/gVSS,由厌氧段至好氧段,EPS总浓度略有升高。不同聚磷污泥的EPS组分均以胞外蛋白为主,占EPS总量的53%~65%,多糖与核酸占EPS总量28%~34%、5%~7%。三维荧光光谱显示3种聚磷污泥EPS均具有芳香结构蛋白质、可溶性代谢物的荧光峰,另外,以硝氮为电子受体的聚磷污泥还具有明显的腐殖酸类物质的荧光峰。研究结果表明电子受体对聚磷污泥EPS的组分、浓度、有机质类别有一定的影响。 相似文献
87.
以乌鲁木齐市某集中供热锅炉污染物减排方案为例,通过建立脱硫除尘设施综合评价指标体系,运用层次分析法确定指标权重,利用模糊综合评判法分别对两种除尘设施情况下的环境效益、经济效益以及设施能耗、物耗等指标着手,进行综合评价,最终评选出较优实施方案.评选结果表明:袋式除尘+石灰石-石膏法脱硫除尘设施方案运用于该集中供热站综合效益较好,可有效实现污染物减排,为今后燃煤锅炉环保设施的评选提供一定的参考作用. 相似文献
88.
建立了高效液相色谱法测定水中六种邻苯二甲酸酯(邻苯二甲酸二甲酯、邻笨二甲酸二乙酯、邻苯二甲酸二丁酯、邻苯二甲酸二(2-乙基己基)酯、邻苯二甲酸二辛酯、邻苯二甲酸丁基苄酯)的检测方法.对水样中邻苯二甲酸酯的萃取条件和高效液相色谱分析条件进行优化,采用正己烷二次萃取,浓缩定容后分析,以乙腈-水为流动相梯度洗脱,紫外检测波长226 nm,16 min可将六种邻苯二甲酸酯分离出.方法的检出限为0.13μg/L ~0.37 μg/L,加标回收率为78.6%~118.5%,相对标准偏差为0.82%~2.17%,是一种理想的测定水中六种邻苯二甲酸酯的方法. 相似文献
89.
伊犁地区位于我国新疆地区西北部,为天山山脉环绕。区内降水自西向东递增,而温
度则由于海拔高度的抬升而逐渐降低。上述地理环境有利于分析和探讨温度和降水与黄土沉积
物中次生细粒强磁性颗粒数量之间关系。本研究在伊犁河谷西部地区,对不同海拔高度黄土表
层沉积物进行样品采集。环境磁学分析结果显示:黄土沉积物中次生细粒强磁性矿物含量与降
水量之间存在很好的正相关关系,而与温度之间存在反相关关系。结合黄土高原的研究结果可
以发现:温度对黄土沉积物中次生细粒强磁性矿物的数量影响微弱,降水是控制其含量的主要
因素;即:在黄土古气候研究中,次生细粒强磁性矿物的磁化率可以作为古降水量的代用指标,
但对温度变化不敏感。 相似文献
90.