Search for: steam
0.006 seconds
Total 105 records

    Retrofitting a steam power cycle by using water from the interstage feed water pump as reheat spray

    , Article ASME Power Conference 2008, Lake Buena Vista, FL, 22 July 2008 through 24 July 2008 ; July , 2008 , Pages 23-30 ; 9780791848326 (ISBN) Saeedi, M. H ; Irani Rahaghi, A ; Mousavi, M. S ; Power Division, ASME ; Sharif University of Technology
    Various methods are used in thermal power plants to adjust the superheated or reheated steam temperature to a pre-determined set point, including flue gas recirculation, using tilting burners and spray of water from discharge of feed water pump, etc. In this paper, an innovative method is presented to control the reheater temperature by tapping water from an interstage of the feed water pump to control reheater temperature at the Bisotoun Power Plant (a steam cycle based power plant in the western Iran). The spray water for the superheaters is secured from the discharge of feed water pump, but interstage water, instead of gas recirculation or using tilting burner, is used to control the... 

    The applicability of expanding solvent steam-assisted gravity drainage (ES-SAGD) in fractured systems

    , Article Petroleum Science and Technology ; Volume 28, Issue 18 , Oct , 2010 , Pages 1906-1918 ; 10916466 (ISSN) Fatemi, S. M ; Sharif University of Technology
    The aim of this contribution is to evaluate the performance of an expanding solvent steam assisted gravity drainage (ES-SAGD) process in naturally fractured systems. Steam-assisted gravity drainage (SAGD) and ES-SAGD processes have been investigated in both conventional and fractured reservoir models and the effect of networked fractures on the recovery mechanism and performance of ES-SAGD has been investigated. Operational parameters such as steam quality, vertical distances between wells, and steam injection temperature have been also evaluated. Finally, to study the effect of a well's horizontal offset, a staggered ES-SAGD well configuration has been compared to a stacked ES-SAGD  

    The effect of geometrical properties of reservoir shale barriers on the performance of Steam-assisted Gravity Drainage (SAGD)

    , Article Energy Sources, Part A: Recovery, Utilization and Environmental Effects ; Volume 34, Issue 23 , 2012 , Pages 2178-2191 ; 15567036 (ISSN) Fatemi, S. M ; Sharif University of Technology
    Many bitumen reservoirs contain shale layers of varying thickness, lateral extent, and frequency. These shale layers, depending on their size, vertical and horizontal locations, and continuity throughout the reservoir, may act as a flow barrier and severely reduce vertical permeability of the pay zone and slow down the steam-assisted gravity drainage steam chamber development. Therefore, to improve productivity in these reservoirs, understanding of the effects of reservoir heterogeneities has become necessary. This work presents numerical investigation of the effects of shale barriers on steam-assisted gravity drainage performance when applied to produce mobile heavy oil. The most concern of... 

    Thermodynamic optimization of design variables and heat exchangers layout in HRSGs for CCGT, using genetic algorithm

    , Article Applied Thermal Engineering ; Volume 29, Issue 2-3 , 2009 , Pages 290-299 ; 13594311 (ISSN) Mohagheghi, M ; Shayegan, J ; Sharif University of Technology
    The heat recovery steam generator (HRSG) is one of the few equipments that are custom made for combined cycle power plants, and any change in its design affects all performance parameters of a steam cycle directly. Thus providing an optimization tool to optimize its design parameters and the layout of its heat exchangers is of great importance. A new method is introduced for modeling a steam cycle in advanced combined cycles by organizing non-linear equations and their simultaneous solutions by use of the hybrid Newton methods in this article. Thereafter, optimal thermodynamic performance conditions for HRSGs are calculated with the help of the genetic algorithm. In the conclusion, the... 

    Neural Network Meta-Modeling of Steam Assisted Gravity Drainage Oil recovery processes

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 29, Issue 3 , Summer , 2010 , Pages 109-122 ; 10219986 (ISSN) Najeh, A ; Pishvaie, M. R ; Vahid, T ; Sharif University of Technology
    Production of highly viscous tar sand bitumen using Steam Assisted Gravity Drainage (SAGD) with a pair of horizontal wells has advantages over conventional steam flooding. This paper explores the use of Artificial Neural Networks (ANNs) as an alternative to the traditional SAGD simulation approach. Feed forward, multi-layered neural network meta-models are trained through the Back-Error-Propagation (BEP) learning algorithm to provide a versatile SAGD forecasting and analysis framework. The constructed neural network architectures are capable of estimating the recovery factors of the SAGD production as an enhanced oil recovery method satisfactorily. Rigorous studies regarding the hybrid... 

    Comparing different scenarios for thermal enhanced oil recovery in fractured reservoirs using hybrid solar-gas steam generators, a simulation study

    , Article Society of Petroleum Engineers - SPE Europec Featured at 78th EAGE Conference and Exhibition, 30 May 2016 through 2 June 2016 ; 2016 ; 9781613994573 (ISBN) Mirzaie Yegane, M ; Bashtani, F ; Tahmasebi, A ; Ayatollahi, S ; Al Wahaibi, Y. M ; Sharif University of Technology
    Society of Petroleum Engineers  2016
    The application of the renewable energy sources, especially solar energy, for thermal enhanced oil recovery methods as an economical and environmental valuable technique has received many attractions recently. Concentrated Solar Power systems are capable of producing substantial quantities of steam by means of focused sunlight as the heat source for steam generation. This paper aims to investigate viability of using this innovative technology in fractured reservoirs to generate steam instead of using conventional steam generators. A synthetic fractured reservoir with properties similar to those of giant carbonate oil reserves in the Middle East was designed by using commercial thermal... 

    Robust controller design for governing steam turbine power generators

    , Article Proceedings - The 12th International Conference on Electrical Machines and Systems, ICEMS 2009, 15 November 2009 through 18 November 2009, Tokyo ; 2009 ; 9784886860675 (ISBN) Nademi, H ; Tahami, F ; Sharif University of Technology
    The turbine control system is one of the key control loops in the dynamic performance of steam power generation units. In this paper a multivariable PID controller is designed for the governing system of steam turbine power generators. The necessary and sufficient conditions for existence of a strong robust H ∞ dynamic compensator are established in terms of linear matrix inequality (LMI) approach. This controller is designed in succeeding to the existing proportional controller in a power plant. To reach to this goal, the complete dynamic model of an actual turbine-generator including the governor, turbine and generator, are derived. Simulation results show that proposed controller has good... 

    Renewable hydrogen production by ethylene glycol steam reforming over Al2O3 supported Ni-Pt bimetallic nano-catalysts

    , Article Renewable Energy ; Volume 128 , 2018 , Pages 188-199 ; 09601481 (ISSN) Larimi, A ; Khorasheh, F ; Sharif University of Technology
    The steam reforming of ethylene glycol, a simple model compound for biomass-derived liquids, is considered to be an environmentally green process for producing renewable hydrogen. Both Pt and Ni species are known for their catalytic activity under steam reforming reaction conditions. In this investigation, alumina supported Ni-Pt bimetallic catalysts (X wt% Ni-Y wt% Pt/Al2O3 named XNi-YPt) were employed for steam reforming of ethylene glycol. The prepared catalysts were characterized by XRD, BET, H2-TPR, H₂-Chemisorption, and TEM. It was observed that Ni/Pt ratio strongly affected the redox behavior, BET surface area, and particle size of the samples that in turn affected their catalytic... 

    Compartment model for steam reforming of methane in a membrane-assisted bubbling fluidized-bed reactor

    , Article International Journal of Hydrogen Energy ; Volume 34, Issue 3 , 2009 , Pages 1275-1291 ; 03603199 (ISSN) Dehkordi, A.M ; Memari, M ; Sharif University of Technology
    A compartment model was developed to describe the flow pattern of gas within the dense zone of a membrane-assisted fluidized-bed reactor (MAFBR), in the bubbling mode of operation for steam reforming of methane both with (adiabatic) and without (isothermal) entering oxygen. Considering such a flow pattern and using the experimental data reported elsewhere [Roy S, Pruden BB, Adris AM, Grace JR, Lim CJ. Fluidized-bed steam methane reforming with oxygen input. Chem Eng Sci 1999; 54:2095-2102.], the parameters of the developed model (i.e., number of compartments for the bubble and emulsion phases) were determined and fair agreements were obtained between model predictions and experimental data.... 

    Comparing the performance and recovery mechanisms for steam flooding in heavy and light oil reservoirs

    , Article Society of Petroleum Engineers- SPE Heavy Oil Conference ; Volume 1 , 2012 , Pages 28-36 ; 9781622761111 (ISBN) Bagheripour Haghighi, M ; Ayatollahi, S ; Shabaninejad, M ; Sharif University of Technology
    SPE  2012
    The concern over fossil energy shortage for the next decade leads to the extensive research activities in the area of enhanced oil recovery. Steam injection as one of well known EOR process has been used for about five decades to improve the oil production rate and recovery efficiency. Steam flooding is applied to heavy and extra-heavy oil reservoirs; however it could be used in light oil reservoirs in which water injection do not work effectively. Regardless of different performances, this method is an efficient EOR process for both heavy and light oil reservoirs. In this work, two separate numerical models were prepared to investigate steam flooding performance for the recovery of light... 

    Steam reforming of methane in a tapered membrane - Assisted fluidized - Bed reactor: Modeling and simulation

    , Article International Journal of Hydrogen Energy ; Volume 36, Issue 1 , 2011 , Pages 490-504 ; 03603199 (ISSN) Dehkordi, A. M ; Savari, C ; Ghasemi, M ; Sharif University of Technology
    A compartment model was developed to describe the flow pattern of gas within the dense zone of a tapered membrane-assisted fluidized-bed reactor (TMAFBR), in the bubbling mode of operation for steam reforming of methane under wall heat flux. The parameters of the developed model (i.e., number of compartments for the bubble and emulsion phases) were determined using the experimental data reported elsewhere [Adris AM, Lim CJ, Grace JR. The fluidized bed membrane reactor system: a pilot scale experimental study. Chem Eng Sci 1994; 49:5833-43.] and good agreements were obtained between model predictions and corresponding experimental data. The developed model was then utilized to predict the... 

    A non-linear controller design for the evaporator of a heat recovery steam generator

    , Article Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy ; Volume 223, Issue 5 , 2009 , Pages 535-541 ; 09576509 (ISSN) Tahami, F ; Nademi, H ; Sharif University of Technology
    This article addresses a combined approach of sliding mode control (SMC) with generalized predictive control (GPC) to achieve fluid temperature control in the evaporator of a heat recovery steam generator. The evaporator is modelled as a first-order plus dead time process. The model is developed using the experimental data obtained at an actual power plant. An output error identification algorithm is used to minimize the error between the model and the experiments in different operating conditions. A GPC method is exploited to optimize the sliding surface and the coefficients of the switching functions used in SMC. The proposed control schemes are evaluated by thorough simulation for... 

    Design and Manufacture of Steam Jet Propulsion System

    , M.Sc. Thesis Sharif University of Technology Khani Sinige, Mahmood (Author) ; Seif, Mohammad Saeed (Supervisor)
    Nowadays, there is a focus on developing a propulsion system with higher efficiency and performance in comparison to conventional systems. Many diverse systems have been designed for the vessel propulsion and everyday, utilizing new ideas, their performance and energy consumption are being improved. Direct use of steam energy is a noble and new idea. In this research, the steam jet propulsion system has been explained and current worldwide research on the topic has been investigated. Considering the shortage of primary data in the field and the novelty of subject, required information for the manufacturing of a sample model of this special propulsion system has been gathered and a design for... 

    Gas Turbine Performance Enhancement through Steam Injection

    , M.Sc. Thesis Sharif University of Technology Abedinnejad, Shahriyar (Author) ; Ghorbanian, Kaveh (Supervisor)
    The present research deals with the effect of steam injection to gas turbine engines. First, a comparison is made across the possible positions in the gas turbine for steam injection. Commercial software is used to investigate the pros and cons. Second, the investigation is focused on an industrial 4 MW gas turbine engine. Classical cycle and sensitivity analysis are performed and the operating envelope of the gas turbine engine with steam injection at various operating states as well as different environmental conditions is determined. Finally, a simulator based on Matlab Simulink is developed to examine the impact of different design and thermodynamic conditions of steam injection to the... 

    Exergoeconomic optimization of a trigeneration system for heating, cooling and power production purpose based on TRR method and using evolutionary algorithm

    , Article Applied Thermal Engineering ; Volume 36, Issue 1 , 2012 , Pages 113-125 ; 13594311 (ISSN) Ghaebi, H ; Saidi, M. H ; Ahmadi, P ; Sharif University of Technology
    In the present study, exergoeconomic optimization of a trigeneration system for cooling, heating and power purposes has been carried out. The system is made up of air compressor, combustion chamber, gas turbine, dual pressure heat recovery steam generator and absorption chiller in order to produce cooling, heating and power. The design parameters of this study are selected as: air compressor pressure ratio, gas turbine inlet temperature, pinch point temperatures in dual pressure heat recovery steam generator, pressure of steam that enters the generator of absorption chiller, process steam pressure and evaporator of the absorption chiller chilled water outlet temperature. The economic model... 

    Second law based analysis of supplementary firing effects on the Heat Recovery Steam Generator in a combined cycle power plant

    , Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010, Istanbul ; Volume 1 , 2010 , Pages 201-209 ; 9780791849156 (ISBN) Karrabi, H ; Rasoulipour, S ; Sharif University of Technology
    The supplementary firing is one of the techniques which are used to increase the output power of the combined cycle power plants (CCPP). The low construction cost per generated power encourages designers to consider it in the new CCPP. In this paper the thermal and exergy analyses of HRSG for various operating conditions in variation of loads and variation of ambient temperature carried out. They are based on the performance test data at different operating conditions. The objective of these analyses is to present the effects of supplementary firing on gross power output, combined cycle efficiency and the exergy loss in Heat Recovery Steam Generator (HRSG) devices at different ambient... 

    Conceptual design and techno-economic assessment of integrated solar combined cycle system with DSG technology

    , Article Solar Energy ; Volume 84, Issue 9 , September , 2010 , Pages 1696-1705 ; 0038092X (ISSN) Nezammahalleh, H ; Farhadi, F ; Tanhaemami, M ; Sharif University of Technology
    Direct steam generation (DSG) in parabolic trough collectors causes an increase to competitiveness of solar thermal power plants (STPP) by substitution of oil with direct steam generation that results in lower investment and operating costs. In this study the integrated solar combined cycle system with DSG technology is introduced and techno-economic assessment of this plant is reported compared with two conventional cases. Three considered cases are: an integrated solar combined cycle system with DSG technology (ISCCS-DSG), a solar electric generating system (SEGS), and an integrated solar combined cycle system with HTF (heat transfer fluid) technology (ISCCS-HTF).This study shows that... 

    A new semi-analytical modeling of steam-assisted gravity drainage in heavy oil reservoirs

    , Article Journal of Petroleum Science and Engineering ; Volume 69, Issue 3-4 , 2009 , Pages 261-270 ; 09204105 (ISSN) Alali, N ; Pishvaie, M. R ; Jabbari, H ; Sharif University of Technology
    Thermal recovery by steam injection has proven to be an effective means of recovering heavy oil. Forecasts of reservoir response to the application of steam are necessary before starting a steam drive project. Thermal numerical models are available to provide forecasts. However, these models are expensive and consume a great deal of computer time. An alternative to numerical modeling is to use a semi-analytical model. The objective of the current study was to investigate thermal applications of horizontal wells for displacement and gravity drainage processes using analytical modeling as well as reservoir simulation. The main novelties presented in the paper are: a) the transient temperature... 

    Simulation study of Steam Assisted Gravity Drainage (SAGD) in fractured systems

    , Article Oil and Gas Science and Technology ; Volume 64, Issue 4 , 2009 , Pages 477-487 ; 12944475 (ISSN) Fatemi, S. M ; Sharif University of Technology
    The Steam Assisted Gravity Drainage (SAGD) process, a developed Enhanced Oil Recovery (EOR) process to recover oil and bitumen, has been studied theoretically and experimentally in conventional reservoirs and models and is found a promising EOR method for certain heavy oil reservoirs. In this work simulation studies of the SAGD process were made on different fractured models consisting of fractures in both Near Well Region (NWR) and Above Well Region (AWR) and even in the presence of networked fractures. At early stage of the SAGD process in fractured system, steam moves through the fractures first and then the matrix blocks are heated primarily by conduction and possibly some steam... 

    Application of fast-SAGD in naturally fractured heavy oil reservoirs: A case study

    , Article SPE Middle East Oil and Gas Show and Conference, MEOS, Proceedings, Manama ; Volume 3 , March , 2013 , Pages 1946-1953 ; 9781627482851 (ISBN) Hemmati Sarapardeh, A ; Hashemi Kiasari, H ; Alizadeh, N ; Mighani, S ; Kamari, A ; Baker Hughes ; Sharif University of Technology
    Steam injection process has been considered for a long time as an effective method to exploit heavy oil resources. Over the last decades, Steam Assisted Gravity Drainage (SAGD) has been proved as one of the best steam injection methods for recovery of unconventional oil resources. Recently, Fast-SAGD, a modification of the SAGD process, makes use of additional single horizontal wells alongside the SAGD well pair to expand the steam chamber laterally. This method uses fewer wells and reduces the operational cost compared to a SAGD operation requiring paired parallel wells one above the other. The efficiency of this new method in naturally fractured reservoir is not well understood....