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101.
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在以焦炭为填料的生物滴滤塔对挥发性脂肪酸臭气的处理研究中考察了空床停留时间、臭气浓度、体积负荷以及进气温度等参数对净化效果的影响。结果表明,空床停留时间较长时对臭气降解有利。在停留时间超过97 s时,能实现完全降解;此外,净化率随臭气浓度和体积负荷的不断增加呈先增加后降低的趋势。当臭气浓度为24.29 mg/m3即臭气的体积负荷为3 g/(m3·h)时,去除率约为96%;当臭气浓度增至1 345.74 mg/m3即体积负荷增至18 g/(m3·h),去除率达100%;然而,当臭气浓度增至4 934.38 mg/m3即体积负荷增至66 g/(m3·h)时,去除率降至73.1%。另外,进气温度对净化率也有一定程度影响。当进气温度较低时,净化效率相对较高。 相似文献
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诺氟沙星作为一种抗生素广泛应用于人类日常生活,并大量进入水体环境,给水环境质量和生态系统安全带来隐患。研究了由3种不同填料组成的水平流和复合垂直流生物活性滤床对诺氟沙星的去除效果,结果表明,在水力负荷为0.1m^3/(m^2·d)、进水诺氟沙星浓度为392.11—686.17μg/L(平均浓度为500.97μg/L)条件下,复合垂直流滤床对诺氟沙星去除效果普遍好于水平潜流滤床,以沸石为填料的复合垂直流生物活性滤床对诺氟沙星的去除效果最好,平均去除率为80.61%,说明选择合适填料和合适类型的生物活性滤床可以作为去除诺氟沙星的一种有效方法。 相似文献
106.
Wastewater management in small and medium-sized enterprises representing the chemical and food industries was investigated.
The results showed that wastewater discharged from an ink-production factory was highly contaminated with organic pollutants.
Anaerobic biological treatment followed by chemical coagulation using ferric chloride aided with lime proved to be very effective
and produced an effluent that complied with national regulatory standard for wastewater discharge into public sewage network.
Also, management of wastewater from a confectionery factory representing the food sector was carried out. Aerobic biological
treatment using plastic-packed trickling filter proved to be an effective treatment method. However, application of in-plant
control measures alleviated the requirement for the construction of a wastewater treatment plant. The applied pollution prevention
and cleaner production measures involved good housekeeping, recovery of spent chocolate, modification of floor cleaning and
installation of suction devices for the removal of sugar and starch powders. All improvement measures were documented by cost/benefit
analysis. 相似文献
107.
Solute transport in fractured rocks is of major interest in many applications, from the petroleum industry to ground water management. This work focuses on the dispersion process in a transparent replica of a real single fracture. The fracture exhibits strong changes in heterogeneity, with the first half very heterogeneous and the second half fairly homogeneous. Three models have been used to interpret the tracer experiments: the classical advection-dispersion equation (ADE), the continuous time random walk (CTRW), and the stratified model. The main goals were to test these models and to study possible correlations between fitting parameters and heterogeneities. As expected, the solution derived from the ADE equation appears to be unable to model long-time tailing behavior. On the other hand, the results confirm the CTRW robustness and the coefficient beta seems well correlated to heterogeneities. Finally, the stratified model is also able to describe non-Fickian dispersion. The parameters defined by this model are correlated to the heterogeneities of the fracture. 相似文献
108.
采用气体实验法对PPS滤料在SO2气体中腐蚀失效的过程进行了研究.通过实验前后PPS滤料的机械特性、微观特征和化学结构的分析,认为PPS对SO2气体具有良好的耐腐蚀性.但是,随着SO2气体温度的升高,时间的延长及气体体积比提高,PPS 针刺毡滤料的性能有所下降,尤其是高温能加快腐蚀效果.为了延长使用寿命,应使其工作参数在限定的范围内: 在SO2体积比高于700 mL/m3时,应对烟气进行预处理使其体积比低于实验值,或者使烟气的温度控制在170 ℃以下; 如果烟气中SO2体积比超过预定值,烟气温度又高于170 ℃,则PPS针刺毡滤料连续使用时间应不超过96 h. 相似文献
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Karline SoetaertMarilaure Gregoire 《Ecological modelling》2011,222(12):1929-1942
Oxygen (O2), nitrate (NO3), dissolved inorganic carbon (DIC) or pCO2, and pH or total alkalinity (TA), are useful indices of marine chemical, physical and biological processes operating on varying time-scales. Although these properties are increasingly being monitored at high frequency, they have not been extensively used for studying ecosystem dynamics. We test whether we can estimate time-evolving biogeochemical rates (e.g. primary production, respiration, calcification and carbonate dissolution, and nitrification) from synthetic high frequency time-series of O2, NO3, DIC, pCO2, TA or pH. More specifically, a Kalman filter has been implemented in a very simplified biogeochemical model describing the dynamics of O2, NO3, DIC and TA and linking the concentration data to biogeochemical fluxes. Different sets of concentration data are assimilated and biogeochemical rates are estimated. The frequency of assimilation required to get acceptable results is investigated and is compared with the frequency of sampling in the field or in controlled experimental settings.Smoothing of the data to remove data noise before assimilation improves the estimation of the biogeochemical rates. The best estimated rates are obtained when assimilating O2, NO3 and TA although the assimilation of DIC instead of TA also gives satisfactory results. In case pH or pCO2 is assimilated rather than DIC or TA, the linearization of the (now nonlinear) observation equation introduces perturbations and the Kalman filter behaves suboptimal. We conclude that, given the resolution of data required, the tool has potential to estimate biogeochemical rates of the carbonate system under controlled settings. 相似文献