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Propane catalytic cracking on pretreated La-ZSM-5 zeolite during calcination for light olefins production

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Journal of Rare Earths 2017年第6期35卷 542-550页

作者： Roya pouria Leyla Vafi Ramin Karimzadeh Department of Chemical Engineering Tarbiat Modares University Jalal AlAhmad Highway P.O. Box 14155-4838 Tehran Iran

The purpose of this study was to increase light olefins yield and selectivity in catalytic cracking of propane. Pretreatment of ZSM-5 zeolite was performed during calcination. First, lanthanum was loaded on the catalyst by wet impregnation method and then the effect of parameters, such as temperature（400–800 oC）, time（120–480 min） and type of stream, on La-ZSM-5 zeolite was examined during calcination using central composite design（CCD） method. Based on the proposed models, the optimized condition for maximizing selectivity of light olefins for air stream was 680 oC and 310 min and for the nitrogen stream was 735 oC and 173 min that under these conditions, selectivity amount increased 24% for nitrogen stream and 19% for air stream as compared with H-ZSM-5 catalyst. The synthesized catalysts were characterized by X-ray diffraction（XRD） and temperature-programmed desorption（TPD） techniques. According to the results of NH3-TPD, as the temperature increased, the number of strong acid sites（specially Bronsted acid sites） reduced and resulted in increased production of light olefins as well as catalyst stability. Accordingly, stability of the samples calcined with nitrogen stream was higher than the samples calcined with the air stream.

关键词： calcination cracking selectivity zeolite calcined impregnation programmed lanthanum loaded propane

Design aspect of a novel L-shaped pulsed column for liquid–liquid extraction applications: Energy consumption and the characteristics velocity concept

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Chinese Journal of Chemical Engineering 2018年第4期26卷 723-730页

作者： pouria Amani Elham Mohammadi Sahar Akhgar School of Chemical Engineering College of Engineering University of Tehran Chemical Engineering Department Tarbiat Modares University

This article deals with the evaluation of the consumption of energy for a steady state solvent extraction in a novel L-shaped pulsed sieve-plate column, which is highly required for design and optimization of the periodic flow processes for industrial applications. In this regard, a comprehensive evaluation on the energy consumption in case of a pulsed flow for three different chemical systems is conducted and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and the plate free area is investigated as well. Moreover, the concept of characteristic velocity models at flooding points is evaluated with respect to the variation of pressure drop along the column at different operational conditions.

关键词： Solvent extraction Pulsed plate column Pressure drop Energy consumption Pulsed flow Characteristic velocity

Experimental study of a heavy fuel oil atomization by pressure-swirl injector in the application of entrained flow gasifier

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Chinese Journal of Chemical Engineering 2019年第4期27卷 765-771页

作者： pouria Mikaniki Seyed Mohammad Ali Najafi Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology

The available SMD(Sauter mean diameter) correlations on pressure-swirl injectors predict droplet sizing very different from each other, especially for heavy fuels. Also there was a lack in the literature for comparing available correlations. So an experimental study was conducted on a heavy fuel oil(HFO) spray, Mazut 380. A pressure swirl injector was designed and fabricated. The experiments for Mazut at 40℃ and 80℃ were compared with the results for water, including spray half cone angle, breakup length and mean droplet diameter,at different injection pressures. Lower spray angle, higher breakup length and larger droplets were observed for lower injection pressures and higher liquid viscosity. SMD was about 75 μm for water and about 87 μm for Mazut at 80℃. The results for droplet mean diameter were also compared with correlations from previous studies on pressure swirl atomizers. The SMD results show that for water spray, LISA method was in good agreement,also Babu and Ballester correlations were successful when high viscosity fluid was injected.

关键词： Atomization Pressure-swirl injector Mazut Size distribution Fuel Viscosity

Microscopic and macroscopic atomization characteristics of a pressure-swirl atomizer, injecting a viscous fuel oil

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Chinese Journal of Chemical Engineering 2020年第1期28卷 9-22页

作者： Seyed Mohammad Ali Najafi pouria Mikaniki Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology(IUST)P.O.B.16765-163TehranIran

Combustion of heavy fuels is one of the main sources of greenhouse gases, particulate emissions, ashes, NOxand SOx. Gasification is an advanced and environmentally friendly process that generates combustible and clean gas products such as hydrogen. Some entrained flow gasifiers operate with Heavy Fuel Oil(HFO) feedstock. In this application, HFO atomization is very important in determining the performance and efficiency of the *** atomization characteristics of HFO(Mazut) discharging from a pressure-swirl atomizer(PSA) are studied for different pressures difference(Δp) and temperatures in the atmospheric ambient. The investigated parameters include atomizer mass flow rate( _m), discharge coefficient(CD), spray cone angle(θ), breakup length(Lb), the unstable wavelength of undulations on the liquid sheet(λs), global and local SMD(sauter mean diameter) and size distribution of droplets. The characteristics of Mazut sheet breakup are deduced from the shadowgraph technique. The experiments on Mazut film breakup were compared with the predictions obtained from the liquid film breakup model. Validity of the theory for predicting maximum unstable wavelength was investigated for HFO(as a highly viscous liquid). A modification on the formulation of maximum unstable wavelength was presented for HFO. SMD decreases by getting far from the atomizer. The measurement for SMD and θ were compared with the available correlations. The comparisons of the available correlations with the measurements of SMD andθ show a good agreement for Ballester and Varde correlations, respectively. The results show that the experimental sizing data could be presented by Rosin-Rammler distributions very well at different pressure difference and temperatures.

关键词： Gasifier Heavy fuel oil Atomization Pressure-swirl atomizer Mazut Size distribution Wavelength Viscosity

LOCAL GAUSSIAN-COLLOCATION SCHEME TO APPROXIMATE THE SOLUTION OF NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS USING VOLTERRA INTEGRAL EQUATIONS

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Journal of Computational Mathematics 2021年第2期39卷 261-282页

作者： pouria Assari Fatemeh Asadi-Mehregan Mehdi Dehghan Department of Mathematics Faculty of SciencesBu-Ali Sina UniversityHamedan 65178Iran Department of Applied Mathematics Faculty of Mathematics and Computer SciencesAmirkabir University of TechnologyNo.424Hafez Ave.Tehran 15914Iran

This work describes an accurate and effective method for numerically solving a class of nonlinear fractional differential *** start the method,we equivalently convert these types of differential equations to nonlinear fractional Volterra integral equations of the second kind by integrating from both sides of ***,the solution of the mentioned Volterra integral equations can be estimated using the collocation method based on locally supported Gaussian *** local Gaussian-collocation scheme estimates the unknown function utilizing a small set of data instead of all points in the solution domain,so the proposed method uses much less computer memory and volume computing in comparison with global *** apply the composite non-uniform Gauss-Legendre quadrature formula to estimate singular-fractional integrals in the *** of the fact that the proposed scheme requires no cell structures on the domain,it is a meshless ***,we obtain the error analysis of the proposed method and demon-strate that the convergence rate of the approach is arbitrarily *** examples clearly show the reliability and efficiency of the new technique and confirm the theoretical error estimates.

关键词： Nonlinear fractional differential equation Volterra integral equation Gaussian-collocation method Meshless method Error analysis

Determination of safe mud window considering time-dependent variations of temperature and pore pressure:Analytical and numerical approaches

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第5期9卷 900-911页

作者： Alireza Gholilou pouria Behnoud far Stephanie Vialle Mahyar Madadi Western Australian School of Mines Curtin University Department of Petroleum Engineering Amirkabir University of Technology

Wellbore stability is a key to have a successful drilling *** stresses are the main factors affecting wellbore instability and associated problems in drilling *** stresses are significantly impacted by pore pressure variation and thermal stresses in the *** order to address wellbore instability problems,it is important to investigate the mechanisms of rockefluid interaction with respect to thermal and mechanical *** order to understand the induced stresses,different mathematical models have been *** this study,the field equations governing the problem have been derived based on the thermo-poroelastic theory and solved analytically in Laplace *** results are transferred to time domain using Fourier inverse *** difference method is also utilized to validate the *** pressure and temperature distributions around the wellbore have been focused and ***,induced radial and tangential stresses for different cases of cooling and heating of formation are *** addition,the differences between thermo-poroelastic and poroelastic models in situation of permeable and impermeable wellbores are *** is observed that cooling and pore pressure distribution reinforce the induced radial *** cooling can be a tool to control and reduce tangential stress induced due to invasion of drilling *** the next step,safe mud window is obtained using Mohr-Coulomb,Mogi-Coulomb,and modified Lade failure criteria for different *** and pore pressure distributions do not change the minimum allowable wellbore pressure ***,upper limit of mud window is sensitive to induced stresses and it seems vital to consider changes in temperature and pore pressure to avoid any *** widest and narrowest mud windows are proposed by modified Lade and Mohr-Coulomb failure criteria,respectively.

关键词： Mud window Thermo-poroelastic theory Time-dependence Fourier series Induced stresses

Atlas of heating:Identifying regional climate-dependent heat demands in residential buildings of Iran

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Building Simulation 2021年第3期14卷 857-869页

作者： pouria Orouji Ramin Hajian Mojgan Moradi Saeed Mohaghegh Kamran Keynejad Mostafa Sefidgar Energy Department Asiawatt Engineering CompanyTehranIran Niroo Research Institute TehranIran Fouman Faculty of Engineering College of EngineeringUniversity of TehranGilanIran Pardis Islamic Azad University TehranIran

Due to different latitudes and variation of altitude in geographical areas in Iran,the climatic conditions of Iran are such that the variations of the heating degree-days(HDD)are in a broad range of 60 to 3000 for residential buildings in different climatic *** addition,in many cases,the building design and construction processes follow patterns which do not necessarily meet national energy requirements and *** on these two reasons,it is essential to identify the current status of energy consumption indicators in residential *** way,it gets more convenient to adopt new strategies to improve the current state of energy consumption of *** this study,heating energy consumption indices of residential buildings is *** the combination of the results of statistical data analysis,questionnaires,filled in for 500 buildings,and a reference building simulation in different climates of Iran,the heating atlas of residential buildings was *** to the results,the average heating energy index(HE1)of buildings in Iran can be less than 1 to more than 41.3(m^(3)(N.G)/(m^(2)-yr))depending on climatic conditions and building design and construction ***,in the coldest center of province,the average of this index is 26.3(m^(3)(N.G)/(m^(2)-yr))in the hottest one that is equal *** variations of the thermal base load(supply of hot water)varied from less than 13.12 to more than 378.84(m^(3)(N.G)/(person-yr)).In provincial capitals,the lowest thermal base load index(TBLI)of buildings is 24.78 and the highest is 226.49(m^(3)(N.G)/(person-yr)).In this paper,beside charts and tables,results of heating energy consumption indices are also presented in the form of graphical atlases,*** contour plots,to deliver a better picture of the whole country.

关键词： heating atlas reference building heating energy index thermal base load index residential building

Computationally aware systems:Recommended features through a review of 188 definitions and its relevance to advanced simulation

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第1期12卷 112-141页

作者： Reza Irani pouria Sharifian Monfared Mohammad Kazemifard Tuncer Oren Department of Computer Engineering University of Razi KermanshahIran School of Electrical Engineering and Computer Science University of Ottawa OttawaONCanada

In this paper,188 definitions of aware,awareness,conscious,and consciousness,classified in different categories including cognitive science,computation,medicine,neurology,and philosophy,are *** on this systematic review,desirable features of computationally aware systems(CASs)are gleaned and reported.A discussion about the relevance of computational awareness to advanced simulation is also outlined.

关键词： Computational awareness computationally aware systems awareness consciousness computational understanding simulation

An approach for wellbore failure analysis using rock cavings and image processing

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 865-878页

作者： Christopher Skea Alireza Rezagholilou pouria Behnoud Far Raoof Gholami Mohammad Sarmadivleh Department of Petroleum Engineering Curtin University Department of Petroleum Engineering Amirkabir University of Technology

There have been interests to link different cuttings/cavings to various wellbore failure types during drilling. This concept is essential when caliper and image logs are not available. Identification ofwellbore failure during drilling gives more chance of immediate actions before wireline logging program. In this paper, an approach was presented based on the image processing of ditch cuttings. This approach uses the sphericity and roundness of cuttings as input data to classify caving types and subsequently deter- mine the dominant failure type. Likewise, common definitions of cavings were discussed initially before a new criterion is suggested. This quantitative criterion was examined by observations from caliper and acoustic image logs as well. The proposed approach and criterion were implemented on ditch cuttings taken from a well in Western Australia. Results indicate that the primary failure is shear failure （breakout） due to high levels of angular cavings. However, another failure due to the fluid invasion into pre-existing fractures was also recorded by blocky cavings.

关键词： Caving shape Cuttings Drilling Image analysis Wellbore failures Roundness Sphericity