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51.
《能源学会志》2020,93(2):474-481
Removal of SO2 and NO emissions from coal-fired power plants have always been the focus in coal's utilization industries for which traditional wet desulfurization system hold the potential to achieve simultaneous removal of SO2/NOx. In this work, a novel liquid catalyst (tributyl phosphate, TBP) was investigated for the simultaneous removal of SO2 and NOx in a NO pre-oxidation (ozone oxidation) assisted process. The absorption process and reaction mechanism of SO2 and NO2 were studied in a small-scale experimental system, and the removal efficiency of pollutant and the key parameters were examined in a pilot-scale system. The results show that the removal efficiency of NO2 in traditional wet desulfurization system is only 20–40%; however greatly increases to >90% when TBP is added. Moreover, TBP can enhance the NO2 removal performance in the presence of SO2 due to the formation of TBP–NO2–SO32− complex. Considering the oily nature of TBP that can be easily separated, such addition strategy hold great potential for industrial SO2/NOx simultaneously removal. 相似文献
52.
Kaili Xu Yantong Wang Ruiqing Shen Qingsheng Wang 《International Journal of Hydrogen Energy》2018,43(31):14859-14865
For treatment of aluminum dust, a wet dust removal system has been used worldwide. During treatment, aluminum dust is inhaled into a water tank of the dust collector. As hydrogen production reactions are likely to take place in the water tank, there exists a great risk of fire or explosion accidents associated with the wet dust removal system. Based on field research and laboratory experiments, Hydrogen Inhibition Method (HIM) by using CeCl3 solutions was proved capable of inhibiting reactions between aluminum dust and water. When the concentration of CeCl3 solutions reached 6.02 g/L, there was basically no hydrogen gas produced. SEM, EDS and XPS characterizations were used to assess the aluminum particles before and after being reacted with water or CeCl3 solutions, respectively. Shrinking core model was utilized to identify the corresponding chemical reaction kinetics. Additionally, a physicochemical mechanism was established to explain these phenomena. 相似文献
53.
Kunho Lee Juhyun Kang Jaeseok Lee Sanghun Lee Joongmyeon Bae 《International Journal of Hydrogen Energy》2018,43(7):3786-3796
The objective of this study is to evaluate metal-supported solid oxide fuel cells fabricated at low temperatures (~1000 °C) in oxidizing environments using wet chemical coating processes and a catalyst impregnation method. Typically, applying general wet chemical coating processes and heat treatment at low temperature is desirable for fabricating metal-supported solid oxide fuel cells when considering manufacturing productivity and efficiency. However, in the case of conventional anodes, a well-organized structure for high performance is rarely formed by sintering at low temperatures when using general fabrication processes. For this reason, a catalyst-impregnated anode is designed and applied to overcome the above issue. First, to evaluate the electrochemical performance of the designed anode, the area-specific resistances of half-cells are investigated. Then, the newly designed anode is applied to a single cell, and microstructural analysis and electrochemical performance measurements are performed. These results confirm that the catalysts are well distributed, that the electrolyte is fully dense and that the electrochemical performances are reasonable. Additionally, the high durability is also verified through a long-term test over 1000 h. Finally, the metal-supported solid oxide fuel cell with a catalyst-impregnated anode fabricated at low temperature is completely validated through the evaluation of a large-size single cell. 相似文献
54.
Ariana de Souza Soares Afonso Mota Ramos Érica Nascif Rufino Vieira Ellen Silva Lago Vanzela Patrícia Martins de Oliveira Daniele de Almeida Paula 《International Journal of Food Science & Technology》2018,53(9):2229-2238
The goal of this research was to evaluate the use of vacuum impregnation (VI) and soaking techniques (ST) in the application of edible coatings of chitosan and chitosan + lauric acid to minimally processed pumpkins (MPP). The vacuum impregnation method led to greater component incorporation (5.9% and 1.75%, respectively) in the pumpkins when compared to soaking and consequently the formation of more uniform, thicker coatings (25.6 and 22.3 μm, respectively). However, VI caused greater changes in pH, acidity, colour and firmness. Relating to water content and carotenoid content, noncoated pumpkins presented greater losses during the storage period, regardless of impregnation method. The pumpkins with edible coatings, regardless of method, presented lower numbers of psychrotrophic micro‐organisms and coliforms during the storage period. Therefore, soaking was considered the best method for the application of chitosan‐based edible coatings to minimally processed pumpkins, as it led to smaller changes in the properties of the product. 相似文献
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This paper mainly focuses on the development of pressure tracking control logic of electro-hydraulic actuators for vehicle application. This is done to improve and ensure the performance of a precise lower-level controller for evolving modern shift control logic. The required performance is obtained by hysteresis model-based feed-forward control and additional feedback control. The hysteresis and the time delay, which adversely affect pressure control, are well known nonlinear behaviors in electro-hydraulic actuators. In order to cope with the hysteresis, a novel hysteresis model is proposed based on a physical phenomenon. A mathematical model based on a characteristic curve obtained in preliminary experiments is presented using only one tuning parameter, and this model can be inverted easily to construct a feed-forward controller. In addition, a feedback controller is designed considering the stability margin of a time delay system. The feedback control inputs ensure compensation of the feed-forward errors caused by model error and uncertainty. The proposed controller is designed to lower computational cost considering applicability for production vehicles. As a result, the developed pressure controller is applied to a transmission control unit of a production vehicle and verified experimentally for various driving scenarios. 相似文献
57.
《Advanced Powder Technology》2019,30(12):2997-3009
During screening, a liquid stream, besides the vibration, can be applied for the acceleration of the separation. The discrete element method coupled with the smoothed particle hydrodynamics (DEM-SPH) is used to numerically analyse wet continuous screening here. Within the applied DEM-SPH a new simple model for the representation of the screening surface is suggested in this study. In this model, the influence of the screening surface on the fluid is represented using external forces, which act on the SPH particles in close vicinity of the screen. A required validation of the DEM-SPH method for the analysis of a vibrated particle-laden system is performed by comparing obtained DEM-SPH results with the results derived using the DEM coupled with finite volume method. The performed simulations of dry and wet continuous screening demonstrate that flowing water, in most simulated cases, accelerates the separation of particles. The presented study demonstrates the potential of the coupled DEM-SPH method for the analysis of wet screening processes. To our best knowledge, the simulation of wet screening using a two-way coupled numerical DEM-SPH approach not resolving the flow around individual particles is demonstrated in the scientific literature for the first time. 相似文献
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