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A facile strategy was proposed to realize the precise control of zeolitic acidity by selective cracking of a silane with an acid site. Modified ZSM-5 with controllable acidity brought about a highly adjustable propene/ethene (P/E) ratio in the 1-butene cracking. [ABSTRACT FROM AUTHOR]

Fluid catalytic cracking (FCC) catalysts play a central role in the chemical conversion of crude oil fractions. Using scanning transmission X-ray microscopy (STXM) we investigate the chemistry of one fresh and two industrially deactivated (ECAT) FCC catalysts at the single zeolite domain level. Spectro-microscopic data at the Fe L3, La M5, and Al K X-ray absorption edges reveal differing levels of deposited Fe on the ECAT catalysts corresponding with an overall loss in tetrahedral Al within the zeolite domains. Using La as a localization marker, we have developed a novel methodology to map the changing Al distribution of single zeolite domains within real-life FCC catalysts. It was found that significant changes in the zeolite domain size distributions as well as the loss of Al from the zeolite framework occur. Furthermore, inter- and intraparticle heterogeneities in the dealumination process were observed, revealing the complex interplay between metal-mediated pore accessibility loss and zeolite dealumination. [ABSTRACT FROM AUTHOR]

The paper presents an advanced methodology for calculating deflections of statically indeterminate reinforced concrete curved beams with allowance for discrete cracking. The theoretical approach based on the basic principles of nonlinear deformation model and takes into account nonlinear concrete and reinforcement behavior. The methodology for calculating deflections of statically indeterminate curved reinforced concrete beams introduced as a computational algorithm worked out based on “MathCAD-15” computer system. The numerical modelling of indeterminate curved reinforced concrete beams exposed to short duration uniform loading shown as a finite element model in PC “LIRA-SAPR 2014”. Taking into account the results of their theoretical research the authors compare calculation data based on the existing domestic and foreign specification documents with the numerical experiment based upon the authors’ own method. The suggested method can be successfully used for calculation of deflections both of statically indeterminate reinforced curved structures made of ultra-high strength concrete (HSC and HPC types) and of normal or over-reinforced structures. [ABSTRACT FROM AUTHOR]

ABSTRACT Nonreactive and reactive computational fluid dynamic simulations were applied to optimize the design of a laboratory scale jet stirred reactor for measuring intrinsic kinetics of gas-phase and gas-solid reactions, i.e. kinetics determined by chemical steps only and not by heat or mass transfer. In the past these reactors were designed and tested based on empirical design criteria and residence time distribution experiments. This work shows that these do not always capture important local effects that are vital for kinetic studies. First the degree of macro-mixing was evaluated for three different geometries (down case, 45° case and 90° case) by performing in silico residence time distribution experiments at 900 K, showing that with these type of experiments only minor differences are observed. However, the ethane steam cracking simulations revealed major differences, with the 45° case being the most uniform in terms of temperature and the 90° case being by far the worst. The species nonuniformity in all geometries was acceptable and was in some cases even partly masked by important shortcut streams such as those observed in the 90° case. The existing gradients on the substrate surface are sufficiently small to be neglected in modeling efforts. As temperature is the major parameter determining the rate of the surface reactions, the 45° case is suggested as the best geometry for measuring intrinsic kinetics. [ABSTRACT FROM AUTHOR]

A cracking furnace, which is the major unit involved in ethylene production, produces various petrochemical products ranging from ethylene to pitch and determines the production yield of an ethylene plant. It is essential to consider the operational performances of the cracking furnaces and to incorporate them into the whole plant's planning problem. Facing this challenge, this paper developed an optimization model, which integrates the scheduling problem of upstream cracking furnaces and the operational planning of the downstream units under a synchronized global time scale. Moreover, a modified Lagrangian decomposition algorithm is proposed for solving the large-scale mixed integer nonlinear optimization problem. An industrial case study demonstrates the feasibility of the integrated model and the effectiveness of the solution algorithm. [ABSTRACT FROM AUTHOR]

Through analyzing the integrated oil and gas production process, a multi-objective optimization model for the integrated oil and gas production process is established through considering nonlinear reservoir behaviour, multiphase flow in wells, and constraints from the surface facilities. In order to reduce the influence of model parameter uncertainty in the oil and gas production process, an error compensation method based on the Gaussian mixture model (GMM) is proposed to compensate the model. Non- dominated sorting genetic algorithm-II (NSGA-II) is used as the optimization algorithm. Moreover, an operational strategy using post- optimization is applied to solve the optimization model, so as to ensure the feasibility of the obtained optimal set-point. Finally, a novel optimization approach for the oil and gas production process considering model parameter uncertainty is proposed. Simulation results indicate that the proposed optimization method is feasible and effective. [ABSTRACT FROM AUTHOR]

With the current base course material in Western Australia, namely hydrated cement treated crushed rock base (HCTCRB), roads using HCTCRB require excessive maintenance causing from its uncertainties. This study aims to determine specific strength properties of a potential replacement material of a clay-cement stabilized crushed rock. The findings showed that a crushed rock material with a newly developed 3% clay-cement binder, possessed unconfined compressive strengths and resilient moduli significantly greater than that of HCTCRB. The developed stress dependent equation also purports that this material admixture is still exhibiting unbound performance characteristics. A material's ability to acquire the accompanying strength advantages of a 3% clay-cement binder, whilst still potentially resisting common failure methods such as shrinkage cracking, suggests that b a s e d o n its potential performance as a base course layer in a pavement structure, clay-cement stabilized crushed rock base is considerable to be a viable base course material for Western Australia. [ABSTRACT FROM AUTHOR]

This paper presents the research results aimed at the assessment of the impact of the group composition of Kazakhstan and West Siberian heavy vacuum distillate on the yield and composition of the catalytic cracking products. The laboratory research was performed to determine the physical and chemical characteristics and group composition of two samples of the heavy vacuum distillate of Kazakhstan and West Siberian oil. The patterns of changing yield of wet gas, light and heavy gas oil, coke, and gasoline depending on the composition of the feedstock were established using mathematical model of catalytic cracking. [ABSTRACT FROM AUTHOR]

A computational constitutive model is presented to predict matrix cracking evolution in laminates under in-plane loading. Transverse cracks are treated as separate discontinuities in the micro-model that provides damage parameters for the macro-model. Both micro- and macro-models are implemented using finite element analysis, specifically, ANSYS, to avoid limitation of analytical micro-modeling. The computational cost of the micro-model is limited to constructing a database of micro-model predictions a priori. The macro-model is simply a finite element analysis discretization of the structure using plane stress or shell elements in ANSYS. The macro-model queries the database, which effectively becomes a constitutive model. The damage surfaces in the database are obtained from the results of large number of finite element micro-scale (unit-cell) analyses. The proposed procedure is implemented in ANSYS as a usermaterial subroutine for transverse crack initiation and propagation in symmetric cross-ply and [0r/(θ / −θ)s/0n]s laminates under in-plane loads. This method is also examined to study matrix crack evolution in tensile specimen with open hole, and the results found to be in good agreement with available experimental data. [ABSTRACT FROM AUTHOR]

A variety of materials are used in the Oil & Gas industry ranging from carbon steel, stainless steel to nickel alloys, etc. including non-metallic materials as well. Amongst these, carbon steel is the industry favorite because of many of its desirable attributes like machinability, weldability, availability, and cost. Wide use of carbon steel in the industry is also due to the presence of required properties for the specific application. In spite of carbon steel's wide uses, poor workmanship, improper heat treatment, or negligent manufacturing processes can reduce its service life and also can lead to unexpected failures. One such failure case involves carbon steel plate meant for construction of a tank that failed by cracking immediately after the welding operation. A detailed investigation was carried out by means of visual examination, metallographic and chemical analysis, SEM, and EDAX analysis. Microstructure revealed banded pearlitic structure along with a number of inclusions, a few of which were elongated. In conclusion, stresses due to weld joint restraint, elongated inclusions, and high transverse direction stresses after welding resulted in lamellar tearing which propagated in the linear direction along the weld line. [ABSTRACT FROM AUTHOR]

Hydraulic slotting, an efficient technique for underground enhanced coal bed methane (ECBM) recovery, has been widely used in China. However, its pressure relief mechanism is unclear. Thus far, only limited research has been conducted on the relationships among the mechanical properties, flaw parameters, and crack propagation patterns of coal after hydraulic slotting. In addition, because of the limitations of test methods, an in-depth information is not available for this purpose. In this work, numerical models of specimens containing combined flaws are established based on particle flow code method. Our results provide insights into the effects of flaw inclination angle on the mechanical properties, crack propagation patterns, and temporal and spatial evolution rules of stress field in specimens containing combined flaws during the loading process. Besides, based on the initiation position and underlying mechanism, three types of crack initiation modes are identified from the failure processes of specimens. Finally, the crack propagation pattern is quantitatively described by the fractal dimension, which is found to be inversely proportional to the uniaxial compressive strength and elastic modulus of the specimen. To verify the rationality of the numerical simulation results, laboratory tests were conducted and their results match well with those obtained from the numerical simulation. [ABSTRACT FROM AUTHOR]

The physical interpretation of the J integral (i.e., J integral) is clear. J integral is the energy release rate associated with crack extension (i.e., translation of the crack in the x direction). However, the physical interpretation of the J integral remains unclear. In this study, different crack translations in the x direction were selected and tested by calculating the energy release rates associated with the crack translations and comparing them with the theoretical value of the J integral. [ABSTRACT FROM AUTHOR]

Uniform distribution of liquid feed on fluidzed bed increase yield on valuable of products and improves operability in the process of fluid coking, and it is of crucial improtance to optimize the contact between the injected liquid and the bed solids. The moisture in fluidized bed is divided into three groups: (a) free moisture, (b) microagglomerates, and (c) macroagglomerates. The goal of this study was to develop a rapid and reliable experimental technique to assess the liquid-solid contact efficiency resulting from the injection of gas-atomized liquid feed. Immediately after the injection of liquid through an atomization nozzle, the triboelectric charges accumulated on the particles migrated to a grounded electrode through the paths offered by the conductive liquid. The methods based on the in situ measurements of the bed conductance varies with time, therefore, use to detect the liquid distribution on different agglomerates, and the air-liquid ratio effect of nozzle is also presented. [ABSTRACT FROM AUTHOR]

HY zeolite catalysts on montmorillonite, pillared with aluminum hydroxo complexes in different concentrations, have been tested in the cracking of heavy vacuum gas oil (VGO) from the Shymkent refinery (Kazakhstan). It has been shown that the VGO cracking activity of the catalysts is directly related to the textural and acid properties of the samples. The hydrocarbon group and fractional compositions of cracked gas-oline have been determined. [ABSTRACT FROM AUTHOR]

Kinetic predictions for complex reaction systems of hydrocarbons are theoretically and technologically crucial to the petrochemical industry. Among several proposed kinetic models, a lumping kinetic model is a comparatively simple and developed method wherein a complex system is lumped into several pseudo-components. To acquire more accurate mechanistic information, kinetic models at the mechanistic level are developed, such as single-event kinetic and structure-oriented models. However, the number of kinetic parameters increases exponentially in these methods. Lumping kinetic methods are then reexamined, and kinetic models, such as relumping single-event kinetic methods, bimolecular methods, and special pseudo-component methods, are proposed to simplify the reaction system. Many mathematical methods, such as annealing algorithm or artificial neural networks, have also been developed to solve these complex reaction problems. Although a number of complex intrinsic reaction studies have been introduced, the combination of excellent prediction performances and practical industrial applicability remains a central challenge facing this field. This situation motivated this study, to review the recent development of reaction prediction models and their application in industrial processes. Furthermore, the practical applications of these possible pathways of kinetic predictions for mechanistic studies are addressed. [ABSTRACT FROM AUTHOR]

The paper presents the use of selected non-destructive testing methods for the purpose of specifying information on weathering and cracking of surface layers of granite rock massif in the medieval Jeroným Mine (the Czech Republic). This mine has been declared the National Heritage Site of the Czech Republic and its opening as a mining museum to the public is gradually prepared. Geological and geomechanical evaluation documents the possibility to find all kinds of weathering grades of rock massif in this mine. Two non-destructive methods have been tested, namely the measurement of ultrasonic pulse velocity and the measurement of Schmidt hammer rebound value. Field measurements were performed in two selected galleries to verify the application of such methods in specific conditions of underground spaces. Used mining method is one of the parameters later influencing cracking of rock massif. In selected galleries, two different mining methods were used which means that a part of a gallery profile was mined out by hand tools in the Middle Ages and another part of the profile was later mined out by blasting. Measurements in these galleries have enabled to analyse the influence of used mining methods on cracking of rock massif in the impaired zone, and, consequently, on ongoing weathering processes in those zones. [ABSTRACT FROM AUTHOR]

The electromagnetic heating for oil recovery is based on the transformation of electric energy into thermal energy. It happens through a direct interaction between the electromagnetic field and the electrically sensitive particles of the medium. There are different types of electromagnetic heating and the choice of the heating type depends on factors such as reservoir depth, geological heterogeneities, and electrical characteristics of the reservoir constituents. This study was based on reservoirs with characteristics similar to those found in the sedimentary basins of the Brazilian Northeast. The purpose of this work is to analyze the influence of the cracking reactions using electromagnetic heating and the influence of the fractures geometries in the reservoir model proposed. [ABSTRACT FROM PUBLISHER]

The Sichuan Basin is a prime gas-producing basin in China. Besides the giant Neoproterozoic Weiyuan gas field discovered in the central paleo-uplift, an extra giant gas reservoir in the Cambrian in this area has been confirmed in recent years. Although the lower Paleozoic in the southwest (Weiyuan area) is normally pressured, it is overpressured in the central area (Moxi-Gaoshiti area). Combined with the seal distribution, five pressure systems, including three overpressure systems, can be divided based on drill-stem test, mud weight, and sonic transit time data. Overpressures appear at depth interval of 1500 to 4900 m (4921 to 16,076 ft), approximately. Benefiting from the good sealing capacity of the gypsum in the Upper and Middle Triassic, high overpressure (pressure coefficient [r] > 2.0) has been preserved in the Lower Triassic, and the Upper Triassic and Cambrian are moderately overpressured (1.3 < r < 1.7). Mechanisms for various overpressure systems are different. Abnormally high sonic transit time in the Permian indicates disequilibrium compaction overpressure. The analyses of sonic transit time-effective stress suggest that disequilibrium compaction is the primary mechanism for the overpressure in the Upper Triassic Xujiahe Formation, but the Cambrian overpressure system is predominantly associated with fluid expansion, which mainly resulted from gas generation. Furthermore, we consider that the late thermal cracking of oil to gas is a key factor for gas and overpressure preservation in old strata. The high overpressure in the Lower Triassic marine carbonate rocks was caused by oil cracking and gypsum dehydration mechanisms. Combining the origin analysis with the burial and hydrocarbon generation histories, we constructed the Cambrian pore pressure evolution model, which is characterized by roughly normal pressure before 200 Ma, overpressuring from 200 to 90 Ma, and overpressure releasing since 90 Ma. [ABSTRACT FROM AUTHOR]

The results of modeling of thermal cracking of oil sludge activated by electromagnetic radiation are reported. An experimental-statistical model of dependence of wide gas oil fraction yield on radiation frequency, electromagnetic radiation power, and oil sludge activation time is obtained to optimize the cracking process conditions. [ABSTRACT FROM AUTHOR]

The problem of prompt speed and density profile mapping based on mathematical modeling of particle motion in the acceleration section of catalyst pneumotransport lines is discussed. An algorithm is developed to calculate the distribution of these parameters along the longitudinal coordinate of reactor-lifts to improve ergonomic efficiency of operation of reaction-regeneration systems used in oil refining and petrochemical industries. [ABSTRACT FROM AUTHOR]

The characteristics of gas fuels for power plants produced by the partial oxidation at high pressure or by oxidative cracking at ∼750 °C of wet natural gas and associated gas are presented. The introduction of an additional stage of preliminary oxidative conversion (pre-reforming) in a flow reactor at initial oxygen concentrations of 5–8%, pressures of 25–40 bar, and temperatures of 450–600 °C or the oxidative cracking stage at atmospheric pressure and ∼750 °C makes it possible to selectively oxidize “heavy” low-octane components of complex hydrocarbon mixtures and to produce fuel gas mixtures for power plants with a high methane number and a required lower heating value. The preferable oxidation agent is atmospheric air rather than oxygen-enriched air or technical oxygen. The introduction of another additional stage of catalytic carbonylation makes it possible to synthesize a number of valuable GTL products, which can compensate expenses to costs of the proposed refinement of wet natural gas and associated gas. [ABSTRACT FROM AUTHOR]

Calculations are performed to determine ionization potentials and wave parameters for different types of bonds, which allows the minimum time of activation of hydrocarbons containing those bonds to be calculated as well. Results are presented from a study of the effect of the parameters of electromagnetic radiation on the yields of products in the thermal cracking of non-hydrofined oil sludge. The results were used to construct the first mathematical models that make it possible to both interpolate and extrapolate the parameters of the sludge-cracking operation. [ABSTRACT FROM AUTHOR]

The authors aimed to determine the functional properties of binders and asphalt-mixtures modified with a liquid nano-organosilane additive. Hence, conventional and rheological tests of bitumen, Fourier transform infrared spectroscopy, and resilient modulus using indirect tensile test were applied. The results indicated that although this silane-based additive creates a hydrophobic layer over the surface of aggregates, which significantly improve the resistance of asphalt-mixtures against water damage; it has inconsiderable effect on rutting, fatigue, and elastic-response properties of both binders and asphalt mixtures. Furthermore, effect of it on low-temperature cracking of binders is still open for discussion. [ABSTRACT FROM AUTHOR]

In this research, the catalytic effect of four types of clays on crude oil low-temperature oxidation was analyzed in depth via static oxidation tube experiments and DTG-DTA tests. Results show that the LTO reactions are positively brought to a deeper degree by clays through lowering the energy requirement for the oxidation/cracking reactions, accelerating reaction rates, and depositing more coke-like fuel. All samples exhibit endothermic oxidation behavior and their energy requirements are proportional to mass loss rates. Based on catalytic study on the oxidation and thermokinetic behaviors of crude oil, a high degree of consistency is discovered between the two types of thermal analysis methods. [ABSTRACT FROM AUTHOR]

In surrogate modelling, a simple functional approximation of a complex system model is always constructed to reduce the computational expense, and the selection of a suitable surrogate model and a sampling method are key to obtaining a surrogate model for a complex system. To construct an appropriate surrogate model, three methods of adaptive surrogate modelling that use artificial neural networks (ANN) are developed by incorporating a new mechanism for automatically determining the number of hidden nodes and/or a new prediction error-based mixed adaptive sampling method. In the automatic determination, the number of hidden nodes can adaptively change according to the effective rate of parameters in the ANN during the adaptive surrogate modelling process. As a result, an improper number of hidden nodes determined by the empirical method can be avoided. The prediction error-based mixed adaptive sampling method is capable of finding the strong nonlinear behaviour of the underlying system, which is easily missed by the traditional prediction variance-based sampling method. The three methods and the previous method for adaptive surrogate modelling that use ANN are tested and compared in terms of replicating the behaviours of three types of challenge functions to determine the efficacy of the developed methods. Furthermore, these methods are used in an engineering problem of surrogate modelling for a cracking reaction simulator to validate the efficacy of the developed methods. [ABSTRACT FROM AUTHOR]

The physicochemical properties of liquid products from pyrolysis of wood biomass alone and its blend with residual fuel oil are compared. The characteristics of the liquid pyrolysis products with residual fuel oil in the mixed feedstock show a tendency to vary. Thermal conversion of combined sawdust and residual fuel oil in a 1:3 ratio provides the maximum yield and the best physicochemical properties of the liquid bioproduct. The possibility of utilizing the middle-distillate fractions of the pyrolysis products as diesel fuel components is examined. [ABSTRACT FROM AUTHOR]

The hydrocracking of thermal cracking waxes obtained from pyrolysis of polyolefin at 360°C for 120 min has been studied using Ni-loaded molecular sieves catalysts. According to XRD, TPR, and BET data, the presence of nickel oxide did not seem to damage the crystalline framework of the catalytic supports. Hydrocracking experiments were carried out in a stirred autoclave reactor at 300°C for 120 min under 2.0 MPa of hydrogen. The results suggested the existence of a balance between the acid and metal function over bifunctional catalysts, which affects hydrogenation and hydroisomerization of thermal cracking waxes. Hydrocracking reactions took place extensively over mixture of Ni/HBeta and ZSM-5, leading toward higher fractions of gases (30.2%) and diesel (23.5%). The higher fractions of gasoline (33.5%) and lube base oil (19.0%) were obtained over mixture of Ni/HSAPO-11 and ZSM-5. In contrast, hydrocracking reaction occurred in a lower extent over mixture of Ni/NMCM-41 and ZSM-5, which produces lube base oil with lower pour point (–10°C), gasoline and diesel with lower bromine numbers (1.1 and 0.8 g Br2/100 g sample). The viscosity index of lube base oil was in the range of 131–171 over all three mixed catalysts. [ABSTRACT FROM AUTHOR]

The maximizing iso-paraffins (MIP) process, a family craft of fluid catalytic cracking process, is designed to reduce olefin content and increase isoparaffin and aromatic content in gasoline. The authors propose a method used to predict the gasoline yield of MIP process. The prediction model with 17 input variables is based on generalized regression neural network and adaptive boosting (adaboost) algorithm. The mean square error between predictive gasoline yield and actual yield is 2.46. [ABSTRACT FROM PUBLISHER]

Refineries’ production plan modeling with simple planning models such as the fixed yield planning models fail to reflect the operating conditions of the processing units. In this work, an integrated optimization strategy including production planning optimization, search of operating parameters and the operation optimization of fluidized catalytic cracking (FCC) units was proposed. The solution of optimal integration was validated by case studies of a monthly plan for a whole refinery, which included three FCC units. The results indicated that the optimization strategy was efficient in determining a practically executed optimal plan and corresponding operating conditions of FCC units. The integrated refinery planning model predicted higher profit and could provide the feasible or optimal FCC operation conditions. [ABSTRACT FROM PUBLISHER]

Fluid catalytic cracking (FCC) is an essential process for the conversion of gas oil to gasoline. This study is an effort to model the phenomenon numerically using commercial computational fluid dynamics (CFD) software, heavy density catalyst and 4-lump kinetic model. Geometry, boundary conditions and dimensions of industrial riser for catalytic cracking unit are conferred for 2D simulation using commercial CFD code FLUENT 6.3. Continuity, momentum, energy and species transport equations, applicable to two phase solid and gas flow, are used to simulate the physical phenomenon as efficient as possible. This study implements and predicts the use of the granular Eulerian multiphase model with species transport. Time accurate transient problem is solved with the prediction of mass fraction profiles of gas oil, gasoline, light gas and coke. The output curves demonstrate the breaking of heavy hydrocarbon in the presence of catalyst. An approach proposed in this study shows good agreement with the experimental and numerical data available in the literature. [ABSTRACT FROM AUTHOR]

Products of thermal cracking of kerogen of Lower-Middle Cambrian oil shale are studied by modern instrumental analytical methods (FTIR, gas chromatography, mass spectrometry, etc.). The analyses demonstrate that the geopolymer kerogen matrix inherited fragments of lipids synthesized by living organisms, including aliphatic fat acids, both free or bounded into glycerol esters, i.e., animal or vegetable fats. It is shown that vegetable pigments (carotenes and xanthophylls) play a crucial role in the formation of monocyclic structures (including molecular alkylbenzene, alkylphenol, and phenylalkane fragments) in kerogen. Since the studied kerogen is rich in esters, it is worth performing alkaline hydrolysis of its macromolecules (ester saponification) before their thermolysis, which inevitably distorts the initial structure of molecular skeletons. [ABSTRACT FROM AUTHOR]

A discrete six-lump kinetic model for the thermal cracking of vacuum residue in the visbreaking process has been developed, and the time-dependent behavior of each individual lump has been determined. A combination of the heuristic method and gradient-based method (hybrid method) has been taken into account to optimize the parameters of the model. A new concept of objective functions has been presented and applied for optimization, so more acceptable results have been obtained. Such an approach has not been presented before. A number of 60 parameters was considered primarily, which has been reduced to 36 with the aim of flash calculation information, and optimized. The obtained results are in good agreement with experimental data. The analysis of the estimated rate constants showed that the cracking of vacuum residue to lighter products was the more dominant reaction pathway during the visbreaking process over the temperature range of 400-430 °C. [ABSTRACT FROM AUTHOR]

Upstream oil and gas project is an example of multiyear investment that has many uncertainties in the whole of project life time (started from exploration, field development and production). Regarding those uncertainties, the executive management is often driven to make a new decision or strategy which may be totally different from previous taken decision. The Discounted Cash Flow (DCF) method is a most widely used quantitative method to appraise oil and gas field value. Unfortunately DCF method doesn't produce a complete figure of strategy which may address uncertainties appropriately. In contrary, Real Option method is a method that already captured those uncertainties through probability and volatility metrics. Real Option provides a complete figure of strategy for the whole life time, therefore Real Option method delivers more flexibility to the executive management in decision making process. [ABSTRACT FROM AUTHOR]

Initial cracking pressure and locations are important parameters in conducting cross-measure hydraulic fracturing to enhance coal seam permeability in underground coalmines, which are significantly influenced by in-situ stress and occurrence of coal seam. In this study, stress state around cross-measure fracturing boreholes was analyzed using in-situ stress coordinate transformation, then a mathematical model was developed to evaluate initial cracking parameters of borehole assuming the maximum tensile stress criterion. Subsequently, the influences of in-situ stress and occurrence of coal seams on initial cracking pressure and locations in underground coalmines were analyzed using the proposed model. Finally, the proposed model was verified with field test data. The results suggest that the initial cracking pressure increases with the depth cover and coal seam dip angle. However, it decreases with the increase in azimuth of major principle stress. The results also indicate that the initial cracking locations concentrated in the second and fourth quadrant in polar coordinate, and shifted direction to the strike of coal seam as coal seam dip angle and azimuth of maximum principle stress increase. Field investigation revealed consistent rule with the developed model that the initial cracking pressure increases with the coal seam dip angle. Therefore, the proposed mathematical model provides theoretical insight to analyze the initial cracking parameters during cross-measure hydraulic fracturing for underground coalmines. [ABSTRACT FROM AUTHOR]

A novel polygeneration process is presented in this paper that co-produces olefins, methanol, dimethyl ether, and electricity from conventional pipeline natural gas and different kinds of shale gases. Technical analyses of many variants of the process are performed, considering differences in power generation strategy and gas type. The technical analysis results show that the efficiency of the plant varies between 22%–57% (HHV) depending on the product portfolio. The efficiency is higher than a traditional methanol-to-olefin process, which enables it to be competitive with traditional naphtha cracking plants. [ABSTRACT FROM AUTHOR]

In this paper, techno-economic analyses of a polygeneration system for the production of olefins, transportation fuels and electricity are performed, considering various process options. Derivative-free optimization algorithms were coupled with Aspen Plus simulation models to determine the optimum product portfolio as a function of a wide variety of market prices. The optimization results show that the proposed plant is capable of producing olefins with the same production costs as traditional petrochemical routes while having effectively zero process CO2 emissions (including the utilities). This provides an economic and more sustainable alternative to traditional naphtha cracking. [ABSTRACT FROM AUTHOR]

Jatropha oil was cracked over micoporous catalysts, such as HY, HZSM-5, and HMordenite, at the optimized conditions obtained over Hβ towards cracking of jatropha oil. The synthesized catalysts were characterized by X-ray diffraction, Brunauer-Emmett-Teller surface area analyzer, inductively coupled plasma, and temperature programmed desorption techniques. Among the microporous materials, HZSM-5 catalyst was found to be the best in terms of conversion (62%), selectivity towards green gasoline (50%), and less coke formation (0.8%) in the cracking of jatropha oil. Cracking of other oils, such as castor, neem, and pongamia, under the optimized conditions resulted in 82% conversion of castor oil; however, higher selectivity towards green gasoline (49%) was obtained in the cracking of pongamia oil. [ABSTRACT FROM PUBLISHER]

Few previous studies have focused on solid bitumen distribution and its effect on gas reservoir quality during oil cracking. Solid bitumen is commonly found in both gas and nongas reservoirs of the Triassic Feixianguan Formation (T1f) in the Jiannan gas field. The T1f natural gases are mainly secondary cracking gases of oil generated from source rock of the Permian Wujiaping Formation (P2w), and the reservoir experienced temperatures above 150°C (302°F) for about 35 m. y. A relatively narrow range of ln(C1/C2) values and a wide range of ln(C2/C3) values and widespread solid bitumen indicate that oil cracking took place in the gas field. Low concentrations of H2S (commonly <0.81%) suggest that high-reflectance (2.57%-3.07%) solid bitumens are pyrobitumens, which would have been mainly derived from oil cracking. Gases preferentially occupy larger pore spaces, and oil is displaced into small pores and throats by overpressure during oil cracking. In this way, pyrobitumens can reduce the magnitude of porosity in relatively tight reservoirs. Moderate-quality oil reservoirs (paleoporosity 2.2%-8.0%) are between or adjacent to high-quality oil reservoirs and are probably poor-quality or non-gas reservoirs after oil cracking. Carbonate reservoirs (paleoporosity >8.0%) can be high-quality gas reservoirs after oil cracking and should be favorable targets for future gas exploration in the northeastern Sichuan Basin and adjacent areas. [ABSTRACT FROM AUTHOR]

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A kinetic model of steam-cracking in industrial-scale steam crackers was developed by a combination of mechanistic and empirical approach. Kinetic parameters of the model were optimized using the data of process experiments, carried out in full-scale industrial crackers, the product yields being determined by hot-gas sampling for the usual types of feedstock, including ethane, liquefied petroleum gas, gasoline, atmospheric gas oil, and hydrocracked vacuum distillate. Experimental and simulated results were compared for a wide range of feedstock and reaction conditions. Data on cracker control parameters and feedstock composition were collected by monitoring the whole production unit consisting of ten crackers and simulation results of total production compared to those of process balance. [ABSTRACT FROM AUTHOR]

Steam cracking belongs to the most important processes in petrochemical industry. Steam cracking is accompanied always by formation of coke deposits on inner walls of steam cracking tubes and of TLE. Coke formation significantly and negatively influences economic and energetic balance of the process. Different ways to minimize the coke deposition in steam cracking units are searched together with detailed understanding of coke formation mechanisms. The amount and character of created coke depends on operating parameters, feedstock type, on the reactor and TLE material, their surface modifications and also on addition of inhibitors. Summary of information about coke formation during steam cracking and of coke inhibition methods is given. [ABSTRACT FROM AUTHOR]

A novel process design for a more cost-effective, greener process for making chemicals from shale gas and bioethanol is presented. The oxidative coupling of methane and cocracking technologies are considered for converting methane and light natural gas liquids, into value-added chemicals. Overall, the process includes four process areas: gas treatment, gas to chemicals, methane-to-ethylene, and bioethanol-to-ethylene. A simulation-optimization method based on the NSGA-II algorithm for the life cycle optimization of the process modeled in the Aspen HYSYS is developed. An energy integration model is also fluidly nested using the mixed-integer linear programming. The results show that for a 'good choice' optimal design, the minimum ethylene selling price is $655.1/ton and the unit global-warming potential of ethylene is 0.030 kg CO2-eq/kg in the low carbon shale gas scenario, and $877.2/ton and 0.360 kg CO2-eq/kg in the high carbon shale gas scenario. © 2014 American Institute of Chemical Engineers AIChE J, 61: 1209-1232, 2015 [ABSTRACT FROM AUTHOR]

This paper investigates how small entrepreneurial firms in two peripheral regions developed by entering the oil and gas industry. The paper draws on previous studies related to the establishment of strategic alliances and emerging clusters and contributes to these research streams by examining the disadvantages of peripheral localization and small firm size. We use a longitudinal case study based on primary data consisting of 54 in-depth interviews conducted between 2007 and 2012 to illustrate that when large-scale oil and gas projects enter a peripheral region, oil companies can moderate local firms' disadvantages related to peripheral localization by actively facilitating relationships with established national firms. By facilitating such relationships and maintaining an active moderating role, strategic alliances and emerging cluster structures can arise. A cross-case analysis illustrates that the oil company had a decisive role in one of the two cases in two dimensions: its role as intermediary between local firms and national firms and its role in fostering the development of an emerging cluster structure by stimulating the establishment of new firms through the oil and gas project. In the second case, the oil company was unable to facilitate regional development. [ABSTRACT FROM AUTHOR]

This study aimed to prepare KF/CaO catalyst with high catalytic activity that can be applied to produce bio-fuel from Cornus wisoniana oil. The KF/CaO catalyst was characterized by Brunauer-Emmett-Teller surface area (BET), XRD, scanning electron microscopy (SEM), and temperature programmed desorption (TPD). The chemical compositions of C. wisoniana oil and bio-fuel oil were analyzed by GC-MS. The effect of the catalyst preparation conditions on catalytic activity was investigated. The optimal process conditions for the KF/CaO preparation were KF loading rate of 40%, calcination temperature of 600°C, and 4 h calcination time. Under the optimum process conditions, the bio-fuel yield reached 82.7 and 65% bio-fuel yield was obtained after being reused nine times. The bio-fuel oil obtained by catalytic cracking has similar chemical compositions to petroleum-based diesel, which exhibited good fuel properties. KF/CaO was used as a catalyst for the production of bio-fuel from cracking of Cornus wisoniana oil. [ABSTRACT FROM AUTHOR]

The ethylene production plant is one of the most important units in petrochemical industry, and the ethylene cracking furnace is the heart of the plant. The ethylene cracking furnace is a multivariable, strong coupling, and nonlinear process, and therefore, it is difficult to be manipulated by traditional proportional–integral–derivative controls. This paper reports a real application of advanced process control in five 470-kton/year SC-I tubular reactors. The advanced process control deployed includes cracking outlet temperature control and feed volume control. This control system has been operating since 2012. The variation of cracking outlet temperature has been reduced from ±5 to ±1 °C with a setting time less than a few minutes even under a large-scale disturbance. The variation of feed volume has been controlled within ±1%. As a result, the advanced process control system has achieved a total production increase by 0.3%. [ABSTRACT FROM PUBLISHER]