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871.
Chenghang Zheng Zhongyang Zhao Yishan Guo Haitao Zhao Weiguo Weng Weihang Zhu 《Journal of the Air & Waste Management Association (1995)》2020,70(7):708-720
ABSTRACT
Electrostatic precipitators (ESP) have been considered as the main particulate matter (PM) removal facility in the energy industry. This paper presents a real-time optimization method for a one-chamber industrial ESP in an ultra-low emission power plant with an intelligent optimization system (IOS). The IOS seeks to optimize the energy consumption of ESP subject to the outlet concentration requirement in real-time. A coordination control logic is designed to regulate the optimized operation set points with varying operation conditions. The operation optimized by the IOS is compared with the operations under PID (proportion-integral-derivative) and manual control. The results show that the IOS improves the emission compliance rate from 95% of manual control to 100% and the medium concentration is tuned to be 46.6% closer to the emission target. Furthermore, a good balance between emission and energy consumption is achieved, with 35.50% energy conservation for the same emission upper limit of 30 mg/m3. These results prove that the IOS significantly contributes to the efficient operation and economic PM removal by ESP for the energy industry. 相似文献
872.
873.
The photocatalytic oxidation of pyrene preadsorbed on TiO2 is examined in aqueous suspension under UV irradiation. Chemical oxygen demand measurements, UV-VIS spectrophotometer, infrared spectrometer and GC-MS analytical techniques were used to monitor the formed intermediates. During the oxidation processes, the ring-open reaction, hydroxylation and ketolysis occurred to produce some intermediate products (4-oxapyrene-5-one, 1,6- or 1,8-pyrenediones, 4,5-phenanthrenedialdehyde, cyclopenta[def]phenanthrene). Some factors affecting the photodegradation rate were also studied. The results were different from other studies: The pH of the dispersion, ratio of Py/TiO2:water had little effect on the photooxidation rate of pyrene catalyzed by TiO2, while the surface coverage, addition of Fe3+ affected it greatly. 相似文献
874.
Li HY Qu JH Zhao X Liu HJ 《Journal of environmental science and health. Part. B》2004,39(5-6):791-803
The effects of Fe(II), Mn(III) and humic substances on the catalyzed ozonation of alachlor, an endocrine disruptor were investigated. Results revealed that small amounts of Fe(II), Mn(II), and humic substances could enhance the ozonation of alachlor, but larger amounts of them would retard the oxidation. These results were successfully identified by an electron paramagnetic resonance (EPR) spectroscopy spin-trapping method that could quantify hydroxyl radicals. The production of hydroxyl radicals was obviously increased with the increasing of Fe(II) concentration, which contributed to enhance ozonation at low concentrations. But the excess Fe(II) consumed some of the radicals when it was added at a higher concentration (1.5 mg/L). However, no obvious radicals were observed when a different amount of Mn(II) was used, and the catalytic ozonation of alachlor by Mn(II) mainly followed the mechanism of "active sites created on the surface of MnO2." The radical pathway was followed when alachlor was ozonated with different concentrations of humic substances because of its radical initiating, promoting, and inhibiting effects. 相似文献
875.
US/UV联用降解荧光增白剂CBW的研究 总被引:2,自引:0,他引:2
对超声波、紫外联用技术降解荧光增白剂的反应进行研究,考察了辐射时间、超声功率、pH、H2O2投加量等因素对降解效率的影响。结果表明:荧光增白剂的降解效率受辐射时间影响较大,降解过程符合拟一级反应I提高超声波的功率可提高荧光增白剂的降解率;H2O2的添加,可使溶液中的氢氧自由基的浓度增加,从而提高了荧光增白剂的降解率。在初始浓度为40mg/L,超声功率为500w、pH为9、H2O2的添加量为30mL/L、反应120min的条件下,荧光增白剂的降解率可达95%。 相似文献
876.
877.
878.
879.
矿化垃圾生物反应床处理NOX废气的研究 总被引:2,自引:0,他引:2
矿化垃圾(稳定化垃圾)是一种良好的生物介质,可作为生物反应床的填料处理NOX废气.实验室研究表明,稳定化垃圾反应床可有效地处理NOX气体,其硝化能力(以N计)可达0.83
g/(kg·d)(干重).NOX去除率受停留时间的影响显著,NOX去除率随着停留时间的缩短而降低.当空床停留时间为1.5
min时,NOX气体的平均去除率为76.7%;空床停留时间为15 min时,NOX气体的平均去除率为91.0%.在NOX进气负荷低于110
mmol/(m3·h)时,NOX消除能力随进气负荷的增加而线性增加.当进气流量一定时,NOX去除能力随着进气NOX浓度的增加而线性增加. 相似文献
880.
采用SBR反应器(厌氧/缺氧/好氧工艺),分别研究了乙酸盐及硝酸盐浓度变化对反硝化除磷的影响特性.试验结果表明,当进水COD浓度>230 mg/L时,乙酸盐浓度的变化对释磷、除磷速率等影响并不显著.在硝酸盐浓度<30 mg/L时,硝酸盐浓度越高,缺氧段除磷速率也就越高.在C/P>23,C/N>5条件下,SBR系统对磷、氮去除率在90%以上. 相似文献