Several series of cracking tests in a comprehensive study were conducted on separate occasions involving all or parts of ten Canadian vacuum gas oils (VGOs) and two catalysts with bottoms-cracking or octane-barrel ca...Several series of cracking tests in a comprehensive study were conducted on separate occasions involving all or parts of ten Canadian vacuum gas oils (VGOs) and two catalysts with bottoms-cracking or octane-barrel capability. VGOs were cracked in fixed- and/or fluid-bed microactivity test (MAT) units, in an Advanced Cracking Evaluation (ACE) unit, and in a modified ARCO riser reactor. Individual yields of gas, liquid, and coke from the MATs at 55, 65, 70, and 81 wt% conversion levels were compared with their respective pilot plant data. Good linear correlations could be established between MAT and riser yields except for liquefied petroleum gas (LPG) and light cycle oil (LCO). At a given conversion, correlations existed among the fixed- and fluid-bed MAT units and the ACE for each product yield. Liquid products from the fixed or fluid-bed MAT were analyzed for hydrocarbon types, sulfur, nitrogen and density, most of which showed good agreement with those obtained from the riser study. When cracking Canadian oil-sands-derived VGOs, the bottoms-cracking catalyst containing a large-pore active matrix was found to be more suitable than the octane-barrel catalyst with smaller pores to produce higher yields of valuable distillates, but with less superior qualities (in terms of sulfur and nitrogen contents). The advantages of hydrotreating some poor feeds to improve product yields and qualities were demonstrated and discussed.展开更多
A novel control method for a general class of nonlinear systems using fuzzy logic systems （FLSs） is presertted. Indirect and direct methods are combined to design the adaptive fuzzy output feedback controller and a ...A novel control method for a general class of nonlinear systems using fuzzy logic systems （FLSs） is presertted. Indirect and direct methods are combined to design the adaptive fuzzy output feedback controller and a high-gain observer is used to estimate the derivatives of the system output. The closed-loop system is proven to be semiglobally uniformly ultimately bounded. In addition, it is shown that if the approximation accuracy of the fuzzy logic system is high enough and the observer gain is chosen sufficiently large, an arbitrarily small tracking error can be achieved. Simulation results verify the effectiveness of the newly designed scheme and the theoretical discussion.展开更多
Designing high-gain observers(HGOs)for the state estimation of an electric vehicle’s electrohydraulic brake(EHB)system is challenging.This type of observer is applicable to model nonlinearities and constant feature g...Designing high-gain observers(HGOs)for the state estimation of an electric vehicle’s electrohydraulic brake(EHB)system is challenging.This type of observer is applicable to model nonlinearities and constant feature gains.However,they are very sensitive to measurement noise,which is unavoidable in EHB.The first novelty of this study is that it compensates for the measurement noise using a filtered high-gain observer(FHGO)to ensure EHB state estimation.The proposed FHGO provides an estimate of the master cylinder pressure,motor current,and rotor speed from measurements of the rotor position.The second novelty is the design of an extremum-seeking(ES)optimization loop to adjust the FHGO gains online.The performance of the developed FHGO with ES-based online gain optimization was highlighted in the presence of model uncertainties and output measurement noise using a Matlab/Simulink simulation.The superiority of the FHGO(even with a fixed gain)over a standard high gain observer(SHGO)was also demonstrated.展开更多
The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressur...The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, H/O ratio and LHSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the HDS and HDN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of HDN and HDS over Com, Hom1 and Hom2 show that homemade catalysts exhibit higher activities in HDN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.展开更多
This study set out to gain a deeper understanding of a fluid catalytic cracking(FCC)coprocessing approach using canola oil mixed with bitumen-derived heavy gas oil(HGO),for the production of partially-renewable gasoli...This study set out to gain a deeper understanding of a fluid catalytic cracking(FCC)coprocessing approach using canola oil mixed with bitumen-derived heavy gas oil(HGO),for the production of partially-renewable gasoline,with respect to its composition and quality.The FCC coprocessing approach may provide an alternative solution to reducing the carbon footprint and to meet government regulatory demands for renewable transportation fuels.In this study,a mixture of 15 v%canola oil in HGO was catalytically cracked with a commercial equilibrium catalyst under typical FCC conditions.Cracking experiments were performed using a bench-scale Advanced Cracking Evaluation(ACE)unit at a fixed weight hourly space velocity of 8 h^(à1),490–530C,and catalyst/oil ratios of 4–12 g/g.The total liquid product samples were injected via an automatic sampler and a prefractionator(to removet254C)into a gas chromatographic system containing a series of columns,traps,and valves designed to separate each of the hydrocarbon types.The analyzer gives detailed hydrocarbon types of à200C gasoline,classified into paraffins,iso-paraffins,olefins,naphthenes,and aromatics by carbon number up to C_(11)(C_(10)for aromatics).For a feed cracked at a given temperature,the gasoline aromatics show the highest selectivity in terms of weight percent conversion,followed by saturated iso-paraffins,saturated naphthenes,unsaturated iso-paraffins,unsaturated naphthenes,unsaturated normal paraffins,and saturated normal paraffins.As conversion increases,both aromatics and saturated iso-paraffins increase monotonically at the expense of other components.Hydrocarbon type analysis and octane numbers with variation in feed type,process severity(temperature and catalyst/oil ratio),and conversion are also presented and discussed.展开更多
文摘Several series of cracking tests in a comprehensive study were conducted on separate occasions involving all or parts of ten Canadian vacuum gas oils (VGOs) and two catalysts with bottoms-cracking or octane-barrel capability. VGOs were cracked in fixed- and/or fluid-bed microactivity test (MAT) units, in an Advanced Cracking Evaluation (ACE) unit, and in a modified ARCO riser reactor. Individual yields of gas, liquid, and coke from the MATs at 55, 65, 70, and 81 wt% conversion levels were compared with their respective pilot plant data. Good linear correlations could be established between MAT and riser yields except for liquefied petroleum gas (LPG) and light cycle oil (LCO). At a given conversion, correlations existed among the fixed- and fluid-bed MAT units and the ACE for each product yield. Liquid products from the fixed or fluid-bed MAT were analyzed for hydrocarbon types, sulfur, nitrogen and density, most of which showed good agreement with those obtained from the riser study. When cracking Canadian oil-sands-derived VGOs, the bottoms-cracking catalyst containing a large-pore active matrix was found to be more suitable than the octane-barrel catalyst with smaller pores to produce higher yields of valuable distillates, but with less superior qualities (in terms of sulfur and nitrogen contents). The advantages of hydrotreating some poor feeds to improve product yields and qualities were demonstrated and discussed.
基金This project was supported by the National Natural Science Foundation of China (90405011).
文摘A novel control method for a general class of nonlinear systems using fuzzy logic systems （FLSs） is presertted. Indirect and direct methods are combined to design the adaptive fuzzy output feedback controller and a high-gain observer is used to estimate the derivatives of the system output. The closed-loop system is proven to be semiglobally uniformly ultimately bounded. In addition, it is shown that if the approximation accuracy of the fuzzy logic system is high enough and the observer gain is chosen sufficiently large, an arbitrarily small tracking error can be achieved. Simulation results verify the effectiveness of the newly designed scheme and the theoretical discussion.
文摘Designing high-gain observers(HGOs)for the state estimation of an electric vehicle’s electrohydraulic brake(EHB)system is challenging.This type of observer is applicable to model nonlinearities and constant feature gains.However,they are very sensitive to measurement noise,which is unavoidable in EHB.The first novelty of this study is that it compensates for the measurement noise using a filtered high-gain observer(FHGO)to ensure EHB state estimation.The proposed FHGO provides an estimate of the master cylinder pressure,motor current,and rotor speed from measurements of the rotor position.The second novelty is the design of an extremum-seeking(ES)optimization loop to adjust the FHGO gains online.The performance of the developed FHGO with ES-based online gain optimization was highlighted in the presence of model uncertainties and output measurement noise using a Matlab/Simulink simulation.The superiority of the FHGO(even with a fixed gain)over a standard high gain observer(SHGO)was also demonstrated.
基金National Natural Science Foundation of China(20406012) and CNPC program(04A5050102 and 05E7019).
文摘The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, H/O ratio and LHSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the HDS and HDN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of HDN and HDS over Com, Hom1 and Hom2 show that homemade catalysts exhibit higher activities in HDN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.
基金Natural Resources Canada and government of Canada's interdepartmental Program of Energy Research and Development (PERD)
文摘This study set out to gain a deeper understanding of a fluid catalytic cracking(FCC)coprocessing approach using canola oil mixed with bitumen-derived heavy gas oil(HGO),for the production of partially-renewable gasoline,with respect to its composition and quality.The FCC coprocessing approach may provide an alternative solution to reducing the carbon footprint and to meet government regulatory demands for renewable transportation fuels.In this study,a mixture of 15 v%canola oil in HGO was catalytically cracked with a commercial equilibrium catalyst under typical FCC conditions.Cracking experiments were performed using a bench-scale Advanced Cracking Evaluation(ACE)unit at a fixed weight hourly space velocity of 8 h^(à1),490–530C,and catalyst/oil ratios of 4–12 g/g.The total liquid product samples were injected via an automatic sampler and a prefractionator(to removet254C)into a gas chromatographic system containing a series of columns,traps,and valves designed to separate each of the hydrocarbon types.The analyzer gives detailed hydrocarbon types of à200C gasoline,classified into paraffins,iso-paraffins,olefins,naphthenes,and aromatics by carbon number up to C_(11)(C_(10)for aromatics).For a feed cracked at a given temperature,the gasoline aromatics show the highest selectivity in terms of weight percent conversion,followed by saturated iso-paraffins,saturated naphthenes,unsaturated iso-paraffins,unsaturated naphthenes,unsaturated normal paraffins,and saturated normal paraffins.As conversion increases,both aromatics and saturated iso-paraffins increase monotonically at the expense of other components.Hydrocarbon type analysis and octane numbers with variation in feed type,process severity(temperature and catalyst/oil ratio),and conversion are also presented and discussed.
