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711.
Kazunori Fujita Gouki Sasaki Kazuki Kobayashi 《Journal of Material Cycles and Waste Management》1999,1(1):48-52
We have investigated a fabric-filter-supported catalyst for removing harmful solid and gaseous compounds simultaneously from
municipal incinerator exhaust gas. We studied the ways in which the efficiency of NO
x
removal is influenced by filter temperature, gas flow rate, and catalyst content. The reduction of the catalyst content by
mechanical reverse washing was investigated, and the state of the catalyst supported in the fabric filter was also observed
using a scanning electron microscope. The catalyst supported by the fabric filter showed a removal efficiency above 75% when
the filter temperature was 200°C, the gas flow rate was 1 m/min, and the catalyst content of the fabric filter was above 300 g/m2. The catalyst was supported uniformly on the fibers of the fabric filter, and fine catalyst particles remained on the fibers
after mechanical reverse washing.
Received: October 15, 1997 / Accepted: March 19, 1999 相似文献
712.
介绍了利用锅炉炉渣有效去除灰水中灰粒的试验方法,试验发现,炉渣直径和灰水流速直接影响去除效率。 相似文献
713.
用液膜分离技术处理含铅废水 总被引:14,自引:0,他引:14
探讨了水中Pb^2+在以P507为流动载体、LMS-2为表面活性剂的煤油-柠檬酸乳状液液膜体系的传输过程。考察了外相酸度,内水相酸度和浓度,膜相载体浓度,膜相表面活性剂肖度以及乳水比等因素对铅去除率的影响,找到了乳状液液膜体系最佳组成。采用这种分离技术对含Pb^2+100mg/L的水样进行处理,铅去除率可达94%。 相似文献
714.
Louis A. Heifrich Mark Zimmerman Diana L. Weigmann 《Journal of the American Water Resources Association》1995,31(2):307-316
ABSTRACT: Filtering efficiency of the fathead minnow (Pimephales promelas), gizzard shad (Dorosoma cepedianum), carp (Cyprinus carpio), and a freshwater mussel (Elliptio coinpianata) was measured in field and laboratory trials to assess the ability of each species to control phytoplankton and suspended solid densities. All fish species tested were ineffective filterers and generally increased, rather than suppressed, algal and suspended solid concentrations. Filtering efficiencies of fish varied between -354 and 84 percent, depending on the size, shape, abundance, palatability, composition, and resistance to digestion of the particles. Because of poor filtering abilities, unpredictable feeding habits, and sensitivity to stress, the fish species examined are not effective biological controls in waste lagoons. In contrast, the freshwater mussel Elliptio was a highly effective control organism, averaging 66 percent filtering efficiency over a wide size range of algal and suspended particles. Filtration efficiency was positively correlated with mussel density. Elliptio was efficient at filtering small particles, which are particularly difficult to remove. Mean filtration rates ranged from 53 to 134 ml/mussel/h depending on the algal species consumed and algal densities (range 50–180,000 cells/ml) and 3 mg/L/mussel/h on suspended solids (range 14 to 112 mg/L). Water clarification was facilitated by both direct consumption and pseudofeces deposition. Elliptio and probably other mussel species can effectively control algae and suspended solids in wastewater lagoons and eutrophic lakes, if environmental conditions, especially dissolved oxygen levels, are suitable (>5 mg/L) for their survival. 相似文献
715.
Yun-Sheng Yu Manoutchehr Heidari Wang Guang-Te 《Journal of the American Water Resources Association》1989,25(2):295-300
ABSTRACT: Finite element and finite difference representations of the convective-dispersive equation have been widely used in determining contaminant transport in ground water. Due to inherent uncertainties of the transport process, those representations are inexact and contain errors. Errors in field measurements are unavoidable. By combining a numerical model, a measurement equation, and the Kalman filter, optimal estimates of the state variable (contaminant concentration) can be obtained. This paper describes the algorithm and gives a numerical example of contaminant transport in a two-dimensional ground water flow. The results show significant improvement in the estimated concentration distribution by using the filtering technique. 相似文献
716.
An efficient linear Kalman filter has been combined with a coupled atmospheric transport and soil–air exchange model to determine organochlorine pesticides emissions on the regional scale. In this study, results of -HCH emissions from the Great Lakes–St. Lawrence ecosystem, estimated from the coupled model, are presented and discussed. A source receptor technique is used to identify a priori the locations of emission sources of -HCH, the emissions are then updated through a Kalman filtering procedure which minimizes the weighted difference between the predicted mixing ratios from the coupled model and the measured concentrations over the Great Lakes–St. Lawrence river region. Two experiments using the inverse algorithm are carried out. In the first experiment, the coupled atmospheric transport and soil–air exchange model is implemented to predict -HCH air and soil concentrations. Emissions are then updated every 12 days using the updated soil concentrations and emission factors. However, the updated emissions are not input into the coupled atmospheric transport and soil–air exchange model. On the other hand, in the second experiment the updated emissions are fed back to the coupled model, so that the model is reinitialized in each 12 days. The results from the inverse technique for the year 1995 have been compared with grided -HCH emission inventory in Canada, generated by emission factors. It is shown that the estimated emissions of -HCH are consistent with the measured emissions. It is found that the St. Lawrence valley has larger emissions of -HCH than the Great Lakes region, indicating an opposite distribution to the emission usage inventory, but in agreement with the measured -HCH concentration. 相似文献
717.
Operational and Design Considerations of a Trickling Filter for Ammonia Removal from Potable Water 总被引:1,自引:0,他引:1
We studied the steady-state behavior of a mathematical model of a nitrifying trickling filter. In particular, we studied the effect of the operating conditions of the filter on the complete and safe nitrification. We presented the results with the help of the operating diagram of the system and we determined the range of operating conditions resulting in optimal operation. We also computed biofilm thickness along the filter depth and concentration profiles inside the biofilm, and compared them with experimental results found in the literature. The comparison shows very good qualitative agreement between model predictions and experimental data. 相似文献
718.
An ion selective electrode (ISE) for determining Cr(VI) using supported liquid membranes (SLMs) containing trioctylphosphine oxide (TOPO) was investigated in this study. TOPO, as a carrier, had a high selectivity for Cr(VI) against interfering ions such as sulfate, nitrate, nitrite, and chloride. The composition of the SLM was optimized as 0.193 g TOPO/1 mL NPOE (o-nitrophenyl octyl ether)/0.5 g poly (vinyl chloride) for detection of Cr(VI). The Cr(VI) concentration was measured in the range of1 × 10-3 to 1 × 10-6 M with the SLM prepared in the study. It seemed that Cr(VI) was transported in the SLM as a triply charged ion indicated by the slope of the emf response. Selectivity coefficients and detection limits of Cr(VI) in the presence of interfering ions were determined experimentally using the fixed interference method. 相似文献
719.
高效液膜分离富集测定微量铜 总被引:1,自引:0,他引:1
应用高效乳状液膜技术分离、富集水和土壤样品中微量铜(Ⅱ).研究了流动载体(P204)、表面活性剂(SPan80)、膜的增强剂(液体石蜡)、膜溶剂(煤油)和内相解吸剂(2.5mol/LH2SO4)等液膜体系,对分离富集微量铜(Ⅱ)的影响.确定了Span80—P204─液体石蜡─煤油─H2SO4高效液膜体系的最佳组成和最适宜的实验条件.富集后的溶液用1-(2-吡啶偶氮)-2-萘酚(PAN)分光光度法测定铜(Ⅱ).用本法富集水和土壤中微铜(Ⅱ).回收率在99%以上。应用于测定水和土壤中的微量铜.相对标准偏差为1.2%~4.5%。 相似文献
720.
The united membrane biological reactor(UMBR) was studied for the treatment of some simulate and municipal wastewater. The removal efficiency for COD and turbidity are greater than 80% and 99% respectively. Effluent COD is less than 100 mg/L while turbidity less than 5. The removal of LAS in bath wastewater is greater than 70%. In treatment of dinning-hall wastewater, removal of fatty oil is greater than 90%, and its concentration in effluent is less than 5 mg/L. The match of biological reactor and the membrane separation component were calculated. The stable performance of wastewater treatment can be maintained by the optimization of operation conditions and the eleanout of membranes. 相似文献