Methods For Treating Vacuum Gas Oil (Vgo) And Apparatuses For The Same (United States Patent Application 20150184088 – UOP)

CATEGORY: VACUUM GAS OIL
Methods For Treating Vacuum Gas Oil (Vgo) And Apparatuses For The Same (United States Patent Application 20150184088 – UOP)
July 2, 2015
Abstract
Embodiments of apparatuses and methods for treating a vacuum gas oil (VGO) hydrotreating feed are provided. In one example, a method comprises contacting the VGO hydrotreating feed with a first hydrotreating catalyst in the presence of hydrogen at first hydroprocessing conditions effective to form a first hydrotreated effluent. The first hydrotreated effluent is separated to form a hydrotreated VGO-containing stream and a hydrotreated diesel-containing stream. The hydrotreated VGO-containing stream is stripped and fractionated to form a VGO product stream. The hydrotreated diesel-containing stream is combined with a hydrotreated diesel-, naphtha-containing stream to form a combined stream. The combined stream is stripped to form a diesel product stream.
more particularly relates to methods and apparatuses for hydrotreating a VGO hydrotreating feed that contains VGO and diesel range hydrocarbons and further treatment of the hydrotreated effluent to recover a VGO product and a relatively high cetane number diesel product.
BACKGROUND
[0002] Vacuum gas oil (VGO) is a hydrocarbon stream recovered from one or more petrochemical refinery unit operations typically as a side cut from a vacuum column, a crude column and/or a coker column and contains sulfur, nitrogen, and other impurities. VGO can include, for example, light vacuum gas oil, heavy vacuum gas oil, heavy coker gas oil, light coker gas oil, and/or heavy atmospheric gas oil. Prior to treating to upgrade the oil, VGO comprises a range of various hydrocarbons (e.g., paraffins, olefins, naphthenes, aromatics with various molecular weights) with different boiling points at atmospheric pressure including a VGO range hydrocarbon fraction and a diesel range hydrocarbon fraction. For example, untreated VGO (e.g., VGO feedstock for treating) can have an initial boiling point (IBP) of from 270 to 350.degree. C. and a final boiling point (FBP) of from 500 to 580.degree. C. in which the VGO range hydrocarbon fraction has an IBP of from 330 to 360.degree. C. and a FBP of from 500 to 580.degree. C. and the diesel range hydrocarbon fraction has an IBP of from 270 to 300.degree. C. and a FBP of from 360 to 400.degree. C.
[0003] To remove sulfur, nitrogen and the other impurities and to generally upgrade the oil, VGO is hydrotreated and fractionated to form various hydrotreated effluent product streams that include a VGO product draw stream and a diesel product draw stream. The hydrotreated effluent product stream(s) can then be further treated downstream, for example, by a catalytic cracking process to convert and/or further upgrade the stream(s) to higher value refinery products. Unfortunately, the diesel product draw stream from hydrotreating and fractionating is a relatively low value diesel product having a corresponding relatively low cetane number(s). In particular, a cetane number is a measure of the combustible quality of diesel fuel during compression ignition. Higher cetane numbers (e.g., 52 or greater) correspond to higher value diesel products than diesel products having lower cetane numbers. Additionally, during catalytic cracking process of hydrotreated VGO, the resulting diesel range hydrocarbons typically known as light cycle oil (LCO) are still of relatively low value.
[0004] Accordingly, it is desirable to provide apparatuses and methods for treating a VGO feed that comprises primarily VGO and diesel range hydrocarbons to recover a VGO product and a relatively high cetane number diesel product. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.
BRIEF SUMMARY
[0005] Apparatuses and methods for treating a vacuum gas oil (VGO) hydrotreating feed that comprises primarily VGO and diesel range hydrocarbons are provided herein. In accordance with an exemplary embodiment, a method for treating a VGO hydrotreating feed comprises the steps of contacting the VGO hydrotreating feed with a first hydrotreating catalyst in the presence of hydrogen at first hydroprocessing conditions effective to form a first hydrotreated effluent. The first hydrotreated effluent is separated to form a hydrotreated VGO-containing stream and a hydrotreated diesel-containing stream. The hydrotreated VGO-containing stream is stripped and fractionated to form a VGO product stream. The hydrotreated diesel-containing stream is combined with a hydrotreated diesel-, naphtha-containing stream to form a combined stream. The combined stream is stripped to form a diesel product stream.
[0006] In accordance with another exemplary embodiment, a method for treating a VGO hydrotreating feed that comprises primarily VGO and diesel range hydrocarbons is provided. The method comprises the steps of contacting the VGO hydrotreating feed with a first hydrotreating catalyst in the presence of hydrogen in a first hydrotreating reactor that is operating at first hydroprocessing conditions effective to form a first hydrotreated effluent. The first hydrotreated effluent is advanced to a hot separator to form a first gas stream that comprises H.sub.2, H.sub.2S, NH.sub.3, and C.sub.1-C.sub.4 hydrocarbons and a first liquid stream that comprises VGO and diesel range hydrocarbons. The first liquid stream is introduced to a hot flash drum to form a hydrotreated VGO-containing stream and a second gas stream that comprises diesel range hydrocarbons. The hydrotreated VGO-containing stream is stripped in a stripper to form a stripped hydrotreated VGO-containing stream. The stripped hydrotreated VGO-containing stream is fractionated in a fractionator to form a VGO product stream. The second gas stream is cooled and introduced to a cold flash drum to form a hydrotreated diesel-containing stream. The hydrotreated diesel-containing stream is advanced to a diesel hydrotreating and separation zone and combined with a hydrotreated diesel-, naphtha-containing stream to form a combined stream. The combined stream is stripped in the diesel hydrotreating and separation zone to form a diesel product stream.
[0007] In accordance with another exemplary embodiment, an apparatus for treating a VGO hydrotreating feed that comprises primarily VGO and diesel range hydrocarbons is provided. The apparatus comprises a VGO hydrotreating and separation zone that is configured to receive the VGO hydrotreating feed. The VGO hydrotreating and separation zone comprises a first hydrotreating reactor that is configured for contacting the VGO hydrotreating feed with a first hydrotreating catalyst in the presence of hydrogen effective to form a first hydrotreated effluent. A hot separator is in fluid communication with the first hydrotreating reactor and is configured to separate the first hydrotreated effluent into a first gas stream that comprises H.sub.2, H.sub.2S, NH.sub.3, and C.sub.1-C.sub.4 hydrocarbons and a first liquid stream that comprises VGO and diesel range hydrocarbons. A hot flash drum is in fluid communication with the hot separator and is configured to separate the first liquid stream into a hydrotreated VGO-containing stream and a second gas stream that comprises diesel range hydrocarbons. A first stripper is in fluid communication with the hot flash drum and is configured to strip the hydrotreated VGO-containing stream to form a stripped hydrotreated VGO-containing stream. A fractionator is in fluid communication with the first stripper and is configured to fractionate the stripped hydrotreated VGO-containing stream to form a VGO product stream. A cooler and a cold flash drum are in fluid communication with the hot flash drum and are cooperatively configured to cool and remove water from the second gas stream and to form a hydrotreated diesel-containing stream. A diesel hydrotreating and separation zone is in fluid communication with the VGO hydrotreating and separation zone and is configured to receive the hydrotreated diesel-containing stream and a diesel hydrotreating feed that comprises diesel and naphtha range hydrocarbons. The diesel hydrotreating and separation zone comprises a second hydrotreating reactor that is configured for contacting the diesel hydrotreating feed with a second hydrotreating catalyst in the presence of hydrogen effective to form a second hydrotreated effluent. A high pressure separator is in fluid communication with the second hydrotreating reactor and is configured to separate the second hydrotreated effluent into a third gas stream that comprises H.sub.2, H.sub.2S, and NH.sub.3 and a hydrotreated diesel-, naphtha-containing stream. The diesel hydrotreating and separation zone is further configured to combine the hydrotreated diesel-, naphtha-containing stream with the hydrotreated diesel-containing stream to form a combined stream. A second stripper is configured to receive and strip the combined stream to form a diesel product stream.
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Vacuum gas oil hydrocracking performance of bifunctional Mo/Y zeolite catalysts in a semi-batch reactor

CATEGORY: VACUUM GAS OIL 
Vacuum gas oil hydrocracking performance of bifunctional Mo/Y zeolite catalysts in a semi-batch reactor

Type	Journal Article
Author	Reynald Henry
Author	Melaz Tayakout-Fayolle
URL	http://www.sciencedirect.com/science/article/pii/S0920586113003222
Series	International Symposium on Advances in Hydroprocessing of Oil Fractions (ISAHOF 2013)
Volume	220–222
Pages	159-167
Publication	Catalysis Today
Date	March 2014
Abstract	Describes a novel approach to characterize bifunctional catalysts in a complex matrix of hydrotreated vacuum gas oil using a batch reactor test. Researchers conducted triphasic reactions in a reactor equipped with a stationary basket, hydrogen injection and products sampling systems. Bifunctional catalysts containing various relative amounts of alumina-supported NiMo sulfide and zeolite were tested at 400 °C under 120 bars over a number of reaction times. They determined the limiting step defining the total conversion to be the scission of the hydrocarbon chains on acid sites of the zeolite. The increase of the molybdenum to zeolite ratio provided an improvement of middle distillate selectivity.

Modified HZSM-5 as FCC additive for enhancing light olefins yield from catalytic cracking of VGO

CATEGORY: VGO – VACUUM GAS OIL 
Modified HZSM-5 as FCC additive for enhancing light olefins yield from catalytic cracking of VGO

Type	Journal Article
Author	O. Awayssa
Author	N. Al-Yassir
Author	Saudi Arabia Center of Research Excellence in Petroleum Refining & Petrochemicals, King Fahd University of Petroleum & Minerals
URL	http://www.sciencedirect.com/science/article/pii/S0926860X14001744
Volume	477
Pages	172-183
Publication	Applied Catalysis A: General
Date	May 5, 2014
Abstract	Reports a study in which researchers modified HZSM-5 with varying Si/Al2 ratios with Mn and alkaline treatment. They studied them as FCC catalyst additives to enhance the yield of light olefins from catalytic cracking of hydrotreated Arab Light vacuum gas oil (VGO). They assessed the performance of the Mn/HZSM-5 and alkaline treated HZSM-5 additives using a commercial equilibrium USY FCC catalyst (E-Cat) in a fixed-bed micro-activity test unit at 550 °C and various catalyst/oil ratios. They observed that the yield of light olefins over E-Cat containing parent HZSM-5 increased to 18.1, 25.4 and 27.4 wt% for Si/Al2 of 30, 80 and 280, respectively, compared with 15.4 wt% over E-Cat. They obtained further increase in light olefins yield by employing Mn modified HZSM-5 as an additive. The highest light olefins yield of 29.2 wt% was obtained over E-Cat-Mn/HZSM-5. The enhanced production of light olefins over the Mn/HZSM-5 additive is mainly attributed to the decrease in the acid density and the amount of strong acid sites, and (possibly) the partial narrowing of ZSM-5 micropore. Alkaline treated HZSM-5 also exhibited high light olefins yield compared with parent HZSM-5, due to the formation of hierarchical micro-meso topology. The highest light olefins yield of ∼28.3 wt% was obtained over E-Cat-containing alkaline treated HZSM-5.

Conversion of low density polyethylene into fuel through co-processing with vacuum gas oil in a fluid catalytic cracking riser reactor

CATEGORY: FLUID CATALYTIC CRACKING
Fuel Processing Technology, Volume 113, September 2013, Pages 130–140
Conversion of low density polyethylene into fuel through co-processing with vacuum gas oil in a fluid catalytic cracking riser reactor
Andrew O. Odjo (a), Angela N. García (b), Antonio Marcilla (b)
a Proxion Process UK Ltd., London SW1X 0DH, UK
b Research Institute of Chemical Process Engineering, University of Alicante, 03080 Alicante, P. Box 99, Spain
Abstract
Researchers pyrolytically co-processed mixtures of vacuum gas oil and low density polyethylene, a major component of common industrial and consumer household plastics, in a fluid catalytic cracking (FCC) riser reactor as a viable alternative for the energy and petrochemical revalorization of plastic waste into valuable petrochemical feedstocks and fuel within an existing industrial technology.
They employed equilibrium FCC catalyst to catalytically crack the oil–polymer blends at different processing conditions of temperatures between 773 K and 973 K and catalyst feed ratios of 5:1, 7:1 and 10:1. They examined influence of each processing parameter on the cracking gas and liquid yield patterns. They also analyzed the various compositional distributions of the resulting liquids and gaseous products. Results revealed that with relatively minor modifications to existing process superstructure, yields and compositional distributions of products from the fluid catalytic cracking of the oil–polymer blend were in many cases quite similar to those of the processed oil feedstock, indicating the viability of the feedstock co-processing without significant detriment to FCC product yields and quality.
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Hydrocracking of Vacuum Gas Oil: Conversion, Product Yields, and Product Quality over an Industrial Hydrocracking Catalyst System

CATEGORY: VGO - VACUUM GAS OIL
Petroleum Science and Technology, Volume 31, Issue 6, 2013, pages 551-562, DOI:10.1080/10916466.2010.516296
Hydrocracking of Vacuum Gas Oil: Conversion, Product Yields, and Product Quality over an Industrial Hydrocracking Catalyst System
G. Valavarasua & B. Sairamb
a R&D Centre, Hindustan Petroleum Corporation Limited, Whitefield, Bangalore, India
b R&D Centre, Chennai Petroleum Corporation Limited, Manali, Chennai, India
Abstract
Vacuum gas oil fraction obtained from a refinery crude distillation unit was employed to conduct pilot plant experiments were conducted over an industrial hydrotreating/hydrocracking catalyst system. Researchers generated extensive pilot plant data on the performance of industrial hydrocracking catalyst system with respect to conversion, product yields, and product quality at various operating conditions. They conducted the pilot plant experiments in a dual-reactor hydrotreating pilot plant system with downflow mode of operation.
The temperature varied from 360 to 400°C and liquid hourly space velocity varied from 0.8 to 2.4 hr⁻¹, keeping a constant pressure of 170 kg/cm² and H₂/HC feed ratio of 845 L/L. The hydrocracked total liquid product was distilled in a true boiling point distillation unit to obtain yields and qualities of different fractions such as naphtha, kerosene, diesel, and unconverted oil. Authors provide a detailed description of the effect of operating conditions on the performance of the hydrocracking catalyst system.
Full Text Source (Subscription or Fee): http://www.tandfonline.com/doi/abs/10.1080/10916466.2010.516296

Modeling A Vacuum Gas Oil Hydrocracking Reactor Using Axialdispersion

CATEGORY: VGO – VACUUM GAS OIL
Petroleum & Coal 55 (3) 156-168, 2013
Modeling A Vacuum Gas Oil Hydrocracking Reactor Using Axialdispersion
Lumped Kinetics
Sepehr Sadighi
sadighis@ripi.ir
Research Institute of Petroleum Industry (RIPI), Catalysis and Nanotechnology Research Division, West Blvd. Azadi Sport Complex, P.O. Box 14665-137, Tehran, Iran.
Abstract
Hydrocracking of vacuum gas oil (VGO) is used in refinery to produce precious products such as diesel, kerosene and naphtha. In this research, a pilot scale reactor has been used to study the hydrocracking behavior of VGO under the conditions recommended by the catalyst vendor and literature in terms lumping of feed and products. A five lumped kinetic model including thirteen parameters is proposed to predict the yield of the products. The lumping scheme is based on the most added values, i.e. gas, naphtha, kerosene, diesel and the unconverted VGO. At first, the hydrocracking reactor was modeled as an ideal plug flow and its kinetic parameters were estimated by a weighted least square function. The average absolute deviation (AAD%) of the yield prediction by using this strategy is 11.86%, 2.66% lower than the conventional ones. Then, a better agreement between the model outputs and the experimental information, with the AAD% of 10.4% is obtained when selective axial-dispersion coefficients were entered in the model.
Introduction
The present study has focused on developing a network, according to a five-lump approach to predict the most added value products including gas (lights and LPG), naphtha, kerosene and diesel in a pilot scale hydrocracking reactor, which its feed is heavy Iranian VGO. The advantages of this work are: I) by separating kerosene and diesel, the evaluation of the catalyst can be done better because each of these desired products has different worth, usage and finishing process II) by using a weighted least square expression for estimating the kinetic parameters, the average absolute deviation (AAD) of the model is decreased III) for the reason of indispensable non-idealities, an axial-dispersion kinetic model is applied to increase the accuracy of the model in comparison to an ideal flow assumption. The nobility of this work is to consider selective axial-dispersion coefficients in the model, integrated to lumped components, to predict the product yields of a hydrocracking reactor more accurately.
Free Full Text Source: http://www.vurup.sk/sites/vurup.sk/files/downloads/pc_3_2013_sadighi_216.pdf 

Application of Discrete Lumped Kinetic Modeling on Vacuum Gas Oil Hydrocracking

CATEGORY: VGO – VACUUM GAS OIL
China Petroleum Processing and Petrochemical Technology,  2013, Vol. 15, No. 2, pp 67-73
Application of Discrete Lumped Kinetic Modeling on Vacuum Gas Oil Hydrocracking
Han Longnian (1); Fang Xiangchen (2); Peng Chong (2); Zhao Tao (1)
1. Liaoning Shihua University, Fushun, Liaoning 113001;
2. SINOPEC Fushun Research Institute of Petroleum and Petrochemicals)
Abstract:
The kinetic model of vacuum gas oil (VGO) hydrocracking based on discrete lumped approach was investigated, and some improvement was put forward at the same time in this article. A parallel reaction scheme to describe the conversion of VGO into products (gases, gasoline, and diesel) proposed by Orochko was used. The different experimental data were analyzed statistically and then the product distribution and kinetic parameters were simulated by available data. Furthermore, the kinetic parameters were correlated based on the feed property, reaction temperature, and catalyst activity. An optimization code in Matlab 2011b was written to fine-tune these parameters. The model had a favorable ability to predict the product distribution and there was a good agreement between the model predictions and experiment data. Hence, the kinetic parameters indeed had something to do with feed properties, reaction temperature and catalyst activity.
Introduction
Faced with a growing demand for middle distillate and an increasing production of heavy crude oils, the hydrocracking process has become one of the most important secondary petroleum refining processes. This process is versatile, flexible and can be strongly adapted to inferior feed oil with a strong capability to convert the heavy, high-boiling, and high EBP (end boiling point) feedstock to smaller, lower-boiling ones like qualified jet fuel, diesel, lubrication base oil, and naphtha for chemical use.
Hydrocracking takes place over a dual-functional catalyst in a hydrogen-rich, high temperature atmosphere, with other reactions, including hydrodesulfurization, hydrodenitrogenation and other hydrotreating reactions, occurring simultaneously. Despite the successful application of hydrocracking technology in commercial scale, the research on its reaction mechanism and reaction kinetics still lags behind the customer needs.
There are various kinetic models for the VGO hydrocracking reported in the literature, and the lumped model and detailed molecular model are regarded as two main approaches being studied for a long time. Moreover, all of the hydrocracking kinetic models could be included in the two approaches. Among them, the lumped models incorporate the fixed lumped models, discrete lumped models and continuous mixtures involved lumped models. For the hydrocracking models based on the lumping technique, these physical properties such as true boiling point (TBP), carbon number (CN), and molecular weight are usually adopted to divide discrete pseudocomponents (lumps). For the fixed lumped model and discrete lumped model, the major disadvantage is that a change in the cutting scheme of the hydrocracker products or in the number of products requires reformulating the model parameters to refit the data. The so-called continuous lumped model is a general case developed from the discrete lumped model, which allows for prediction of the entire distillation curve, but the dependency of model parameters on feed properties still exists. Furthermore, the distillation curves of heavy oils are not accurate when the feedstock is a mixed oil consisting of VGO, CGO, DAO and other fractions. Detailed approaches include the structure oriented lumped models and the single event models, which express the chemical transformations in terms of typical molecular structures and elementary steps of cation chemistry, respectively. For a relatively large number of pseudo-components the analytical information and experimental data are required, which impose restrictions on their applications to hydrocracking of real feedstocks.
The complexity of real feedstocks suggests that lumped model will continue to be used for the research on VGO hydrocracking kinetics. However, detailed approaches need to be studied more precisely in order to obtain a better understanding of hydrocracking kinetics and provide an idea to optimize lumped model for prediction of hydrocracking product properties. A good kinetic model is a useful tool for reactor design, simulation, and optimization of oil refining processes.
To have a better understanding of the VGO hydrocracking, in this work we conducted some experiments in a pilot plant equipped with two downflow fixed-bed reactors and developed a discrete lumped kinetic model, which will be presented in further papers.
Free Full Text Source: http://www.chinarefining.com/CN/article/downloadArticleFile.do?attachType=PDF&id=180  

Correlation between structure and performanceof vacuum gas oil hydrocracking catalysts in a batch reactor

CATEGORY: HYDROCRACKING
MACS VI, Satillieu : France (2013)
Correlation between structure and performanceof vacuum gas oil hydrocracking catalysts in a batch reactor
R. HENRY  (1), M. Tayakout-Fayolle  (1), P. Afanasiev  (1), C. Lorentz  (1), Gregory Lapisardi, Gerhard Pirngruber
1 Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), CNRS : UMR5256 – Université Claude Bernard - Lyon I
Abstract
To produce the innovative hydrocracking catalysts the refining industry requires for increasingly heavy crudes, the behavior of these catalysts must to be better understood. Researchers present a novel approach for studying and modeling complex reaction kinetics with a batch reactor test.
They built a batch reactor apparatus for this purpose. Triphasic reactions took place in a laboratory-scale reactor equipped with a Robinson-Mahoney stationary basket, a hydrogen injection system and liquid/vapor sampling system. Feedstock was a hydrotreated vacuum gas oil. Reaction conditions were 400°C and 120 bars. Various bifunctional catalysts were characterized and tested over 3 hour and 6 hour-reactions. Gas and liquid samples were then analyzed by one and two-dimensional gas chromatography, in order to obtain precise composition of each phase during the reaction. The lack of mass transfer limitations at vapor-liquid interface and at liquid-solid interface was confirmed by modifying the stirring speed and the size of the catalyst pellets. The method allows access to intrinsic kinetic properties of the catalysts. A follow-up experiment was conducted, with the purpose of testing catalysts containing different amounts of molybdenum and zeolite.
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New innovative HPNA management process to achieve virtually total conversion in a hydrocracker

CATEGORY: HYDROCRACKING
JoP - The Journal of Petrotech, Vol. VIII Issue 8 January - March 2013
New innovative HPNA management process to achieve virtually total conversion in a hydrocracker
Raju Chopra, Mike Hunter, Raj Patel, Sylvain Verdier
Haldor Topsoe India Pvt. Ltd.
Abstract
Hydrocracking is well suited for selective middle distillate production from heavy vacuum gas oils and operation with recycle of unconverted oil for maximizing the conversion to middle distillate products is highly desirable. However, certain undesired side reactions that are characteristic of all catalytic hydrocracking processes result in the production of small quantities of highly condensed aromatic ring structures commonly referred to as Heavy Poly-Nuclear Aromatics or HPNA’s. Unless purged from the system the HPNA’s will build up to unacceptable levels. The undesired formation of HPNA therefore represents a practical limitation on the total conversion achievable in almost all hydrocracking processes. The new innovative and simple HPNA management process reduces the unconverted oil bleed requirement from a hydrocracker and thereby increases the total conversion to distillate products that can be practically achieved.
The new process can deliver substantial economic benefits depending on the relative value of distillate product over the value of purged oil. This benefit is realized by concentrating heavy poly-nuclear aromatics so that the steady state purge requirement can be lowered by 50 to 80%. The process equipment requirements are minimal and can be retrofit to existing units with a low cost modular approach to give a very high return on capital investment.
Introduction
Certain undesired side reactions that are characteristic of all catalytic hydrocracking processes result in the production of small quantities of highly condensed aromatic ring structures commonly referred to as Heavy Poly-Nuclear Aromatics or HPNA’s. Once they are formed, HPNA’s are very difficult to convert catalytically in the process and will build up in the unconverted recycle oil stream unless physically removed from the system most commonly by purging a small quantity of the unconverted oil from the hydrocracker. This bleed stream can represent as little as one percent to as much as 10 percent of the feed and is commonly in the range of two to five percent in many middle distillate hydrocrackers. The undesired formation of HPNA therefore represents a practical limitation on the total conversion achievable in almost all hydrocracking processes. The conversion of this incremental purge to diesel and lighter products can deliver substantial economic benefits depending on the relative value of distillate products over the value of the purged oil. Topsoe’s HPNA Trim™ process is a unique, compact and highly cost effective design to control HPNAs while achieving virtual total conversion in a hydrocracking unit.
Free Full Text Source: http://www.petrotechsociety.org/wp-content/uploads/2013/05/PET081_Journal_final2.pdf#page=45   

Comparison of Kinetic-based and Artificial Neural Network Modeling Methods for a Pilot Scale Vacuum Gas Oil Hydrocracking Reactor

CATEGORY: HYDROCRACKING
Bulletin of Chemical Reaction Engineering & Catalysis, Article In Press 2013
Comparison of Kinetic-based and Artificial Neural Network Modeling Methods for a Pilot Scale Vacuum Gas Oil Hydrocracking Reactor
Sepehr Sadighi
Research Institute of Petroleum Industry (RIPI), Catalysis and Nanotechnology Research Division, West Blvd., Azadi Sport complex, P.O. Box 14665137, Tehran, Islamic Republic Of Iran
Gholam Reza Zahedi
Catalysis and Nanotechnology Research Division, Project Management, Process Systems Engineering Centre (PROSPECT), Faculty of Chemical Engineering, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor Bahru, Johor, Malaysia
Abstract
Authors describe an artificial neural network (ANN) and kinetic-based models for a pilot scale vacuum gas oil (VGO) hydrocracking plant. Experimental data reported in the literature were used to develop, train and check the models. The models are able to predict the yield of all main hydrocracking products including dry gas, light naphtha, heavy naphtha, kerosene, diesel, and unconverted VGO (residue).
Results revealed that kinetic-based and artificial neural models have the specific ability to predict yield of hydrocracking products. The former is able to accurately predict the yield of lighter products i.e., light naphtha, heavy naphtha and kerosene. On the other hand, the ANN model is capable of predicting yields of diesel and residue with higher precision. The comparison shows that the ANN model is superior to the kinetic-base models.
Full Text Source (Subscription or Fee): http://www.ejournal.undip.ac.id/index.php/bcrec/article/view/4722