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Coker kero stream is obtained from delayed coking which contains saturates with alpha olefins and PNA compounds which was physicochemical characterised. The fractions present in coker kero may be used further for value added products such as alkyl benzene and naphthalene etc. The study described potential of coker kero via aromatics and non-aromatics separation by using liquid-liquid extraction (LLE) with N-methyl pyrrolidone (NMP), acetonitrile and methanol as solvents of different polarity. Methanol imparts best colour improvement as per ASTM D-1500. Beside this, adsorption study on coker kero was performed using fuller’s earth, chalk powder, red ochre and wood-stick’s ash as adsorbents. The adsorption study suggested that fuller’s earth not only separate aromatics and non-aromatics form coker kero, but also acts as a better adsorbent than graphitic carbon (activated charcoal) and is found suitable for colour improvement comparatively. This study inferred the separation of polar components, improvement in the colour, odour and established the stable fuel. FT-IR study suggested that N-methyl Pyrrolidone gives better results comparatively other solvents. HC22 type analysis of coker kero raffinate and extract phase confirm the sharp extraction of coker kero feed using N-Methyl pyrrolidone as it is a good solvent for extraction of aromatics. GCMS and HRMS compositional analysis successfully performed for the coker kero and it is separated aromatic and non-aromatic fractions.

PurposeDelays in projects execution due to improper structural design lead to substantial losses to the owners. Little guidelines are available in practice that deals with structural design of Delayed Coker Units (DCUs). This work describes effective structural criteria for design of DCU used in hydrocarbon industry. Economical procedures are described for steel and concrete design. Design of pump houses supporting DCU is also described.Design/methodology/approachNumerical procedures are developed to model pipelines and mechanical equipment loadings. Soil restraints are simulated using horizontal and vertical springs along the pile embedded length. Concrete pile-caps are integrated with steel structure in the analysis model.FindingsThe proposed design approach is cost effective to use in practice. The paper offers economical footprint for design of DCUs that can be used for multiple projects.Practical implicationsThe paper provides useful guidelines that can be utilized by engineers for design of coker heater and coker fractionation stacks, steel modules, coke pump house, deluge building, etc.Originality/valueCurrently, there are no guidelines in practice that deal with structural design of DCU. The present work bridges this gap and describes novel strategies that can be utilized for industrial projects.

The organosulfur compounds of mixed raw materials—vacuum gas oil in a mixture with heavy coking gas oil reactions group kinetic were investigated during hydrotreating at a hydrogen pressure of 5 MPa at various temperatures (360, 390, 420 °C) and LHSV of 0.5, 1.0, 2.0 and 4.0 h−1 in the presence of Ni6–MonW12-n/γ-Al2O3 sulfide catalysts, prepared on the base of phosphoromolybdenum and phosphorotungstenheteropolyacids. The total sulfur content was determined in feed and hydrogenates. A kinetic model describes the process of hydrodesulfurization of vacuum gas oil in hydrotreating on Ni6–MonW12-n/γ-Al2O3 catalysts based on phosphomolybdenum and phosphotungsten heteropolyacides (HPAs) has been selected. The adequacy of the kinetic model of the 2nd order was verified by means of the coefficient of determination and based on the values of the Fisher criterion. The optimal modes of the vacuum distillate hydrotreating process may be selected on the base of obtained data on the kinetics of hydrodesulfurization (HDS) reactions. The kinetic characteristics of the HDS and hydrodearomatization (HDA) reactions of the mixed feed compounds on Ni6–MonW12-n/γ-Al2O3 catalysts based on phosphor–molybdenum and phosphotungsten HPA were determined with the usage of chosen model. The Ni6PMo12/γ-Al2O3 catalyst was most active one in the HDS reaction. The activity of catalyst samples in hydrogenation reactions was investigated. It was shown that the most active sample is Ni6PMo4W8/γ-Al2O3.

The family Saprolegniaceae includes 17 genera, viz., Achlya Nees von Esenbeck, Aphanodictyon Huneycutt ex Dick, Aphanomyces deBary, Aplanopsis Hohnk, Brevilegnia Coker & Couch, Calyptralegnia Coker, Couchia W.W. Martin, Dictyuchus Leitgeb, Geolegnia Coker, Leptolegnia deBary, Phragmosporangium Seymour, Plectospira Drechsler, Protoachlya Coker, Pythiopsis deBary, Saprolegnia Nees von Esenbeck, Sommerstorffia Arnaudow and Thraustotheca Humphrey. The eighteenth genus with its type species named—Girishia indica Prabhuji has been added to this list and has been critically discussed. Girishia indica Prabhuji has been found to be a connecting-link between family Pythiaceae and Saprolegniaceae. The morphological variability of reproductive structures (vegetative, asexual and sexual) in all eighteen members of Saprolegniaceae has been described and their significance has been discussed and reviewed.

Pisolithus tinctorius (Pers.) Coker is an ectomycorrhizal fungus that forms an abundant wealth of biomass in the forest ecosystem, with an untapped treasure of bioactive compounds and secondary metabolites having multifaceted use in health and agrochemical industries. The hidden potential of this fungus is tapped in the current study by using MTP1 isolate of P. tinctorius. The secondary metabolites of P. tinctorius were extracted and tested for their inhibitory efficacy against major soil-borne plant pathogens viz., Fusarium oxysporum f. sp. lycopersici (Sacc.) Synder and Hansen; Macrophomina phaseolina (Goid); Rhizoctonia solani (Kuhn) and Sclerotium rolfsii (Sacc). The cell-free culture (CFC) filtrate of P.tinctorius showed the maximum mycelial inhibition of F. o. f. sp. lycopersici (52.00 %); R. solani (51.92%) and M. phaseolina (48.23%). However, the CFC filtrate mixture did not inhibit the growth of S. rolfsii. The GC-MS analysis of biomolecules composite of ethyl acetate fraction of CFC filtrate indicated the presence of compounds belonging to the nature of fatty acids, aromatic alcohol, and flavonoids. The reduction in the growth of the test pathogens with the increase in the concentration of CFC filtrate and the presence of several unknown compounds in P. tinctorius warrants further study with the purified form of antifungal biomolecules in reducing root rots and wilts incited by the soil-borne phytopathogens.

Elemental sulfur is used to cross-link heavy coker gas oil (HKGO) with only 0.44 wt% olefinic hydrogen content in the absence of solvent; subsequent pyrolysis yields sulfur-doped porous carbon with Brunauer–Emmett–Tell (BET) surface area (s.a.) around 1714–1785 m2 g−1. The heavy coker gas oil does not need demetallation or hydrotreating to enable this. The usual problems (residue metal and sulfur/nitrogen) in HKGO became an opportunity in product carbon to anchor CO2 resulting in high sorption capacity.

A natural hydrogen donor, i.e., a subfraction of the coker gas oil, was used in thermal upgrading of the Venezuela extra-heavy oil. The role of hydrogen donor was quantitatively studied by a combin...

The shocking defamiliarization of the everyday that took place during World War II created a crisis in modernist aesthetics. This crisis emerges both in Eliot’s anguished meditation on time, space, and infinity in “East Coker,” and in Powell and Pressburger’s playful satire about an aging soldier. The curious parallels between these two works are articulated through the figure of the failing human body; in both poem and film, flesh becomes the avatar of a modernist sensorium that struggles to conjoin the perceiving subject with a fugitive and unreliable object world. Specifically, the medicalized body becomes the metaphorical locus of a profound epistemological unease, and the interventionist apparatuses of medicine and of cinema become folded into a more general problematic of style. Whereas Eliot’s poem repeatedly breaks the frame of classical rhyme, meter, and structure in order to express disquiet with the mechanics of the corporeal, Powell’s camera insists that we look steadily at the bodies of his lead actors—one aging before our eyes, one remaining eternally and impossibly the same—as they are worked on by the trickery of cinema, and to marvel at (rather than being repulsed by) the persistence of their intransigent materiality. A new poetics permits the consolation of aesthetic mediation, between the inaccessible metaphysical ideal and the baffling entanglements of human time.

Building off of the work of Kervaire and Milnor, and Hill, Hopkins, and Ravenel, Xu and Wang showed that the only odd dimensions n for which S^n has a unique differentiable structure are 1, 3, 5, and 61. We show that the only even dimensions below 140 for which S^n has a unique differentiable structure are 2, 6, 12, 56, and perhaps 4., Comment: 52 pages. Revised version includes some additional recommendations of referee

This paper presents the results of testing a catalyst system developed for the demetallization and desulfurization of vacuum gas oil and heavy coker gas oil mixture at a pressure of 6 MPa, a temperature of 360-370°C, and a feed volumetric rate of 1 h-1 for obtaining a product having a sulfur content of 0.05 wt.%. The composition of RMB 30 marine fuel is developed with the application of a distillate fraction obtained from secondary processes and a depressant-dispersant additive in order to bring the pour point to the requirements of GOST32510-2013.

This book is a vivid account of an Iraqi intelligence operation led by al-Suquor (‘the Falcons’), an ‘elite’ Iraqi intelligence cell, and an Islamic State of Iraq and Syria (ISIS) counterintelligen...

Demetallization of a mixture of vacuum gas oil with heavy coker gas oil on CoMo/γ-Al2O3 catalysts with different pore structures was studied, and the influence of the catalyst pore structure on the process results was demonstrated. For the demetallization catalysts to be effective, their pore size should be restricted not only from below but also from above. When using samples with broad pores, effects of the hydrodesulfurization and hydrodemetallization inhibition can arise owing to adsorption of supramolecular structures of heavy residues, in particular, of asphaltenes.

Behavior of the CoMo/Al2O3 catalyst was experimentally studied in the course of hydrotreating of a straight-run gas oil with high content of sulfur (>2 wt %) and its mixture (up to 30 wt %) with light coker gas oil in the temperature range 335–365°C and liquid hour space velocity of feedstock deliver of 0.8–2.5 h−1. It was shown that addition of gas oil to the straight-run gas oil in hydrotreating under the conditions corresponding to the working conditions of the existing domestic hydrotreating installations [L-24-5, L-24-6, L(Ch)-24-7] has oppositely directed effects, depending on temperature and feedstock delivery rate. For example, the additives lead in the temperature range 335–350°C to an increase in the content of sulfur in hydrotreating products. At a temperature of 365°C, better sulfur-related parameters are reached in processing of feedstocks containing light coker gas oil. The observed dependences are accounted for as follows: the dilution of the straight-run gas oil by addition of light coker gas oil leads to a decrease in the content of difficulty converted sulfur-containing compounds, but makes larger the content of nitrogen-containing compounds inhibitors of the hydrodesulfurization reaction, the influence of which on the reaction rate becomes weaker with increasing temperature.

Quantitative trait loci (QTLs) qMi-C11 and qMi-C14 impart a high level of resistance to Meloidogyne incognita in cotton. Breeders had previously backcrossed both QTLs into the susceptible Coker 201 to create the highly resistant M-120 RNR, and we crossed Coker 201 and M-120 RNR to create near-isogenic lines with either qMi-C11 or qMi-C14. Previous work suggests different modes of action for qMi-C11 and qMi-C14. To document individual and combined effects of the QTLs on nematode development and reproduction, Coker 201 (neither QTL), M-120 RNR (both QTLs), CH11 near isoline (qMi-C11), and CH14 near isoline (qMi-C14) were inoculated with M. incognita. At 4, 8, 12, 16, 20, 25, and 30 days after inoculation (DAI), roots were stained to observe nematode developmental stages (second-stage juvenile [J2], swollen second-stage juvenile [SJ2], third-stage juvenile [J3], fourth-stage juvenile [J4], and female), and the number of galls was counted. At 20, 25, 30, and 40 DAI, M. incognita eggs were harvested and counted. At 30 DAI, 80% of the nematodes on Coker 201 were female compared with 50, 40, and 33% females on CH14, CH11, and M-120 RNR, respectively, and greater proportions of nematodes remained in J2 in M-120 RNR (41%), CH11 (58%), and CH14 (27%) than in Coker 201 (9%). More nematodes progressed to J3 or J4 on Coker 201 and CH14 than on CH11 or M-120 RNR. Coker 201 and CH14 had more galls than M-120 RNR. Coker 201 had more eggs than the other genotypes at 30 DAI. Nematode development beyond J2 or SJ2 was significantly reduced by qMi-C11, and development beyond J3 or J4 was significantly reduced by qMi-C14. This study confirms that qMi-C11 and qMi-C14 act at different times and have different effects on the development of M. incognita, and therefore, they have different modes of action.

Two NiMo sulfide catalysts, supported on Al2O3 and silica–alumina, respectively, were compared in the hydrotreatment of a mixture of straight-run and coker gas oil. Experiments were conducted in a ...

Coking technological improvements are required to effectively upgrade/refine extra-heavy oil residues. The influence of types and blending ratios of coker-derived liquids on the coking performance ...

To convert Light cycle oil (LCO) with low hydrogen content into more light fraction such as low-carbon olefins and gasoline during the catalytic cracking reaction, it is necessary to replen...

The search applied the evaluation and risk assessment of H2S gas at Suez Oil Processing Company (Coker complex units). Different samples were measured for the Hazard H2S in many places around the Coker units in 2012. TiO2 was prepared by hydrothermal approach in presence of oleic acid. TiO2 was characterized by XRD and SEM. Treatment of the produced H2S was carried out by photocatalysis using (TiO2) phcatalyst and UV light source. The removing efficiency of H2S reaches 98% using UV lamp. The stability and the capacity of the removing were also studied. The degradation reaches 97% 96% after catalyst poisoning through three cycles.

The field trial was conducted at Qwshtapa district , Grdmala village, which is 30 km far from center of Erbil city to compare between nine genotypes of cotton (Gossipum hirsutum L) during the growing season 2016, the genotypes were (Coker 310, Lachata ‘Iraqi genotypes ’ Cafko, Dunn 1047, Montana, Stone Ville ‘ USA genotypes ‘, Bakhtegon, Khdorda , Vanamin Iranian genotypes ) using randomized complete block design (RCBD)with three replicates. any fertilizers were not added to the field during the research and Irrigation was done using Statistical analysis of the traits shown significant differences among genotypes , Coker 310 obtained the highest value for number of fruiting brunches, number of Bolls plant-1،Boll weight )g(, seed yield plant-1, ginning% and oil% with values of (8.93 ,29.27,4.23, ,77.67, 39.87 and 28.33 ) respectively. Lashata genotype recorded highest value of protein and linoleic acid % which were (34.82 and 63.68) % respectively. Depending on growth stage, agronomic characteristics and their quality the genotypes were discerning to three main clusters, the first one included (Lachata and Stone Ville) genotypes, while the second clusters indicated only Cafko genotype and the third cluster included (Coker 310, Dunn 1047and, Montana, Bakhtegon , Khdorda and Vanamin) genotypes.

Fanny Coker is the focus of this chapter by Christine Eickelmann. She represents a group of women whose stories have been mostly lost to British history—plantation-born domestic servants. Eickelmann outlines what we know of Fanny’s timeline: Born on the Mountravers sugar plantation on Nevis to an enslaved black woman and, likely, the white plantation manager, Fanny spent her adult life in England working for the family of Mountravers’ owner, John Pinney who freed and educated her. Settling in Bristol with the Pinneys, Fanny was separated from family and the plantation community and left to navigate a new country and employer dynamics on her own. Choosing to stay with the Pinneys her whole life, Eickelman describes how she maintained connections to family in the West Indies through letters, gifts and one extended visit, and was part of a larger network of information and economic exchange across the Atlantic. Operating under the strictures of her employer as a lady’s maid under annual contract, she managed to be baptized in the Baptist church, build financial security through investments and an inheritance and, unlike most of her plantation counterparts, realize some agency over shaping her life. Learning about Coker’s life, says Eickelmann, is an important window into the stories of black servants, especially women, in Georgian England.

A Radioactive Particle Tracking (RPT) technique was used to study the effects of the internal baffles in the stripping section of the Fluid Coker™, called sheds, have on the behavior of wet agglomerates that are formed when residual oil is injected into the Coker. Vapor emitted by reacting wet agglomerates below the sheds rises and causes shed fouling. The release of vapor from agglomerates can be estimated by combining the RPT results with a coking reaction model. The study found that the sheds reduce the time agglomerates spend in the shed zone, which in turn reduces the amount of organic vapor that reaches the sheds, but at the same time increase the wetness of the agglomerates that exit to the recirculation line, which results in the loss of valuable liquid. The research also found that the best type of shed, from the point of view of agglomerate motion, is the mesh-shed. Finally, experimental data indicate that reducing the cross sectional area of the sheds from 50% to 30% increases the time that the agglomerates spend above the shed zone, and thus reduces the flow of vapor emitted below the sheds.

The coking behavior of serial petroleum residues derived from deep-vacuum distillation of Venezuela extra-heavy oil has been systematically investigated in laboratory-scale coking appliances from the perspectives of distribution and properties of coking products. The usage of residue with deeper distilling cut would favor the decreasing of low-value products, i.e., coke and coking gas. The hydrogen circumstance of coking feedstock indicated by 1H NMR analysis, implies residue with ultra-deep distilling cut as a valid hydrogen evolution potential. By comparison with the de-metallization rate in the hydrodemetallization process (Ni, 61.2%; V, 80.8%) (Zhang et al., 2006), the performance in the study seems more promising. Evidently, the stripping of VGO would notably change the morphological characteristics of resultant coke. However, no secondary assembled or clustered shot coke was observed in the coker, which made the decoking quite easy. A valid linear agreement between the area of green region quantitatively assessing the process flexibility and the metal content has been established. The extrapolation (dot line) of the trend suggests that shot coke formation cannot be avoided in any circumstance of the study if the metal content of coking feedstock is over 1516 μg g−1.

Delayed coking is one of the most widely used residue upgradation process in crude oil refining where vacuum residue is thermally cracked and converted into distillates and petroleum coke. During heating of vacuum residue in coker furnace, coke is continuously deposited in furnace tubes which is removed at regular intervals by one of the three methods namely (i) pigging, (ii) steam air decoking or (iii) online spalling (OLS). OLS is one of the preferred methods of coke removal from coker furnace tubes. We have noticed very effective as well as “not so effective” OLS in a commercial delayed coker furnace. In present article, the changes in composition and properties of furnace coke during effective and ineffective OLS were systematically analyzed by various analytical tools such as Dilatometer, TGA, HRSEM, SEM-EDX and XRD. Based on these analyses, it was found that inorganic deposits such as iron sulphides and tube metal corrosion products play a major role in failure of OLS. Higher total acid number (TAN) of vacuum residue may be promoting the formation of iron sulfide deposits in furnace tube.

Inferior coker gas oil (ICGO) derived from Venezuelan vacuum residue delayed coking is difficult to process using fluid catalytic cracking (FCC) or hydrocracking (HDC). The high content of nitrogen and condensed aromatics leads to major coking and readily deactivates the acid catalyst. In this work, a sequence of hydrotreating (HDT) and FCC processing is used to effectively convert ICGO to a high-value light oil product. The results show a higher overall conversion and a significant increase in the yield of gasoline compared to FCC processing. Molecular level characterization of the nitrogen compounds and condensed aromatics before and after HDT confirms that the nitrogen content and the 2+-ring aromatic content decreased, whereas the single-ring aromatics increased. The nitrogen compounds were mainly N1, N1O1, N1O2, and N1S1 class species in basic nitrogen and N1, N1O1, N1O2, N2, and N2O1 class species in non-basic nitrogen. Moreover, the double bond equivalent of these species shifted to lower values. T...

This work presents a model for UOP Coker Complex Hydrotreating Process using Aspen HYSYS Petroleum Refining module. The model depends on routinely taken industrial data of process streams during normal operating conditions. Acquired data sets have been tested and screened in order to ensure data validity for building the model and avoiding erroneous results. A detailed kinetic model of hydrotreating reactions in the reactor has been applied. The trickle bed reactor (TBR) model has been validated using 3 months of industrial plant data. In addition, rigorous tray-by-tray simulations for hydrogen sulfide absorption tower and TBR effluent fractionation tower have been utilized to match the performance of the plant’s towers. The model has been used then for studying the effects of different process variables on the plant performance. In addition, the model has been used in optimizing the operating conditions of the process. This optimization showed a potential for notable savings of fuel and energy consumption in the process, while increasing the process productivity.

The influence of the introduction of V2O5 into NiMo/Al2O3 catalysts on their activity in hydrodesulfurization (HDS) and hydrogenation reactions of the components of petroleum fractions has been studied. The activity of the synthesized catalysts has been determined in the straight-run diesel and light coker gas oil hydrotreating processes in a flow-through unit under hydrogen pressure. The most active catalyst for HDS and hydrogenation of polycyclic aromatic hydrocarbons has been synthesized using VMo12 heteropoly compounds: the activity increases by 6–10 and 11–13 wt % in HDS and PAH hydrogenation, respectively, at different temperatures. It has been shown that the activity of the regenerated catalyst further impregnated with the vanadium compound in HDS and PAH hydrogenation increases by 2–5 rel. %, as compared to the regenerated catalyst.

Naphtha reforming processes are widely used for high-octane gasoline production. These processes require high reaction temperature and high pressure of expensive hydrogen. Also, olefins and aromatics are produced for achieving high octane number, which could cause severe environmental issues. Here, we report a novel method of non-thermal plasma assisted catalytic reforming of naphtha at near ambient conditions. Conventionally used hydrogen has been replaced by cheaper methane in this study. Non-thermal plasma could effectively convert methane and naphtha to high-quality fuel at near room temperature and atmospheric pressure. A high-quality fuel with high content of iso-paraffin and low content of olefin and aromatic is produced over optimized Ga/mix-ZSM-5 with non-thermal plasma applied. The produced liquid product has a notably higher iso-paraffin content (increased from 21.5%–40.5%) than raw naphtha while the coke deposition (17.4 %) and the content of olefins (decreased from 13.5%–7.8%) and aromatics (dropped from 18.1%–5.9%) are well controlled. The partial desulfurization of fed coker naphtha by close to 60 % is also successfully achieved. A systematic model compounds study is conducted to investigate the involved mechanism of non-thermal plasma assisted catalytic naphtha reforming and coke deposition. Based on the studies of C6-C16 model compounds (including paraffins, olefins, dienes, cyclo-paraffins, cyclo-olefins and aromatics), a hypothetic reaction mechanism is proposed. A series of control experiments is also carried out to reveal the synergistic effect between non-thermal plasma, catalyst, and methane participation. This research thus pioneers a cost-effective and environmental-friendly route for naphtha reforming at mild conditions.

In fluidized bed reactors such as Fluid CokersTM, liquid injections are used. Good contact between liquid and bed solids is required to maximize product yields and quality, and gas-atomized nozzles are, therefore, used in all these processes. The spray nozzle technology is known to affect the liquid distribution. Therefore, the objective of this study is to assess the effect on liquid distribution of a draft tube located downstream of the spray nozzle, inside the fluidized bed. Experiments were conducted at a relevant scale, using a commercial-scale nozzle with a liquid flow rate of about 100 L/min in a large-scale pilot fluid bed containing about 7 tonnes of silica sand. Liquid injected into a fluidized bed either forms liquid-solid agglomerates or free moisture, consisting of individual particles coated with a thin layer of liquid. Several electrodes were used to map the free moisture distribution throughout the bed. A draft tube greatly improves the contact efficiency throughout the bed. It also increases the penetration of the gas-liquid jet formed by spray inside the fluidized bed. This article is protected by copyright. All rights reserved

Activated carbon injection has been proven to be an effective control technology of mercury emission from coal-fired power plants. Petroleum coke is a waste by-product of petroleum refining with large quantities readily available around the world. Due to its high inherent sulfur content, petroleum coke is an attractive raw material for developing mercury capture sorbent, converting a waste material to a value-added product of important environmental applications. In this study, petroleum coke was brominated by chemical-mechanical bromination. The brominated petroleum coke was characterized for thermal stability, mercury capture capacity, and potential mercury and bromine leaching hazards. Bromine loaded on the petroleum coke was found to be stable up to 200°C. Even after treating the brominated petroleum coke for 30min at 600°C, 1/3 bromine remained on the solid. The sorbent from bromination of sulfur-containing petroleum coke was shown to be a promising alternative to commercial brominated activated carbon for capture of elemental mercury from coal combustion flue gases.

Two narrow fractions distilled from Liaohe coker gas oil were used for the research. The distribution of basic nitrogen compounds in feedstocks and their liquid products were characterized by ESI FT-ICR MS. The results showed that N1 class species were the most predominant in both feedstocks and products. The catalytic cracking progress reduced the relative abundance of all class species, except for the N1 and N1S1 class species. Although the N1 class species had longer side chains and higher condensation in the heavier feedstock, the distribution of N1 class species became similar in the two liquid products.

Multi-lump kinetic models for model compounds representative of various sulfur (S) and nitrogen (N) compounds in coker gas oil (CGO) were developed to describe CGO hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) processes, respectively. Model parameters were obtained from fitting of operating data. Validation results revealed that models could predict contents of S and N in products accurately, and hydrogen consumption of HDS and HDN can be estimated. The effects of the temperature, hydrogen/oil ratio, and pressure on the reaction performance were also investigated.

Refineries process a number of gas oils such as straight run gas oil (SRGO), light cycle gas oil, coker gas oil and visbreaker gas oil for producing a common gas oil pool to be used as a transportation fuel. Considering stringent sulfur standards, new strategies and design modifications are being evaluated for desulfurization of these gas oils with minimum loss of oil during the desulfurization process. In this review, developments in solvent extractive desulfurization of gas oil have been discussed from both fundamental and applied point of views. Various performance indicators used for solvent evaluation/screening in computational and experimental studies are discussed. Particular emphasis has been given on latest developments in performance evaluation of organic and ionic liquid solvents for desulfurization of SRGO and other gas oils. Various possible designs of solvent recovery section to remove solvent from raffinate and extract phases for solvent recycling have been reviewed. Various potential optio...

The skirts of four coke drums of a delayed coker plant in an oil refinery became severely cracked as result of the service and a poor design. The cracks were located in the circumference just below the welded joint of the skirt with the pressure vessel of the coke drums. Since the cracks grew up to one hundred percent of the circumference, the drums were free to move both laterally and vertically. The present paper describes the results of the measurement of these displacements, as well as other non destructive test, done in order to analyze by finite element the mechanical behavior of the skirt and the drum-skirt system. The results showed that the greatest risk of failure was the plastic collapse of the skirt due to an uneven distribution of the vertical loads resulting from the lateral and vertical displacements of the drum. The analysis is used then to propose a unique reinforcement of the skirt that allows to fully rehabilitate the coker drums without re-welding the fractured skirts.

The objective of the present study is to develop a better hydrodesulfurization (HDS) kinetic model on the basis of a fundamental and comprehensive understanding of the different HDS reactivities of various sulfur compounds in middle distillates and the inhibition effects of the coexisting nitrogen and aromatic compounds. Five middle distillates blended from straight run gas oil, heavy gas oil, and coker gas oil were hydrodesulfurized over a commercial catalyst at 300 °C, 4.0 MPa H2 pressure, a H2/oil volume ratio of 200, and different liquid hourly space velocities. Identification and quantification of sulfur compounds in the feedstocks and their hydrodesulfurized products were conducted by using GC-PFPD to classify the sulfur compounds into four groups according to their molecular structures and reactivities. It was found that the HDS of each sulfur group follows pseudo-first-order kinetics. Correlation of the obtained first-order rate constants with both the nitrogen concentration and the feedstock dens...

Bibliography: Shah, Nisha: Christopher Coker, Can War Be Eliminated?, ERIS, 2-2016, pp. 111-114. https://doi.org/10.3224/eris.v3i2.12