Material Balance Calculations Research Articles

Flowsheets of multicomponent multiphase systems separation and material balance calculation features

The applicability of a method for determining the number of free variables required to solve the balance task for flowsheets with a Florentine vessel or decanter during the separation of multicomponent mixtures has been considered. The rule and algorithm that allows one to determine the number of the free variables schemes with recycles have been formulated and proposed.

Applicability of the shape-factor concept for naturally fractured reservoirs and an alternative approach

After 60 years of worldwide scientific efforts, the authors do not see a chance of formulating the matrix-fracture mass transfer rate, as it happens in naturally fractured hydrocarbon reservoirs, in one, generally applicable expression. Numerous approaches for it have been presented, but none of them considered all possible conditions and for none of them experimental evidence was presented. Therefore, the only consistent approach is a numerical calculation on a fine scale single matrix block (SMB) model. Heinemann (2004) suggested using the recovery curves resulting from SMB calculation directly in any dual continuum formulation. Mittermeir (2015) did so in material balance calculation. It is proved that this approach has the potential for being generally applicable.

Material Balance And Reaction Kinetics Modeling For Penex Isomerization Process In Daura Refinery

Penex Deisohexanizer isomerization of light straight run naphtha is a significant process for petroleum refining and proved to be effective technology to produce gasoline components with a high octane number. Modeling of the chemical kinetic reactions is an important tool because it is a better tool for optimization of the experimental data into parameters used for industrial reactors. The present study deals on the isomerization process in Daura refinery. Material balance calculations were done mathematically on the unit for the kinetics prediction purpose. A kinetic mathematical model was derived for the prediction rate constants K 1 and K 2 and activation energy Ea at operating temperatures range 120-180°C. According to the model, the results show that with increasing of temperature leads to increased K 1 directly, where the K 2 values proportional inversely. The activation energy results show that Ea 1 (nC6) 1(C5) 1 (CH) , and for Ea 2 (iC5) 2 (2,2-DMB) 2 (2,3-DMB) 2 (MCP)..

Work plan for improving the DARWIN2.3 depleted material balance calculation of nuclides of interest for the fuel cycle

DARWIN2.3 is the reference package used for fuel cycle applications in France. It solves the Boltzmann and Bateman equations in a coupling way, with the European JEFF-3.1.1 nuclear data library, to compute the fuel cycle values of interest. It includes both deterministic transport codes APOLLO2 (for light water reactors) and ERANOS2 (for fast reactors), and the DARWIN/PEPIN2 depletion code, each of them being developed by CEA/DEN with the support of its industrial partners. The DARWIN2.3 package has been experimentally validated for pressurized and boiling water reactors, as well as for sodium fast reactors; this experimental validation relies on the analysis of post-irradiation experiments (PIE). The DARWIN2.3 experimental validation work points out some isotopes for which the depleted concentration calculation can be improved. Some other nuclides have no available experimental validation, and their concentration calculation uncertainty is provided by the propagation of a priori nuclear data uncertainties. This paper describes the work plan of studies initiated this year to improve the accuracy of the DARWIN2.3 depleted material balance calculation concerning some nuclides of interest for the fuel cycle.

A Petrophysical Dual-Porosity Model for Evaluation of Secondary Mineralization and Tortuosity in Naturally Fractured Reservoirs

Summary Quantification of secondary mineralization or cementation within natural fractures has not been considered in previous petrophysical dual-porosity models. This is, however, of paramount importance because morphology of the fractures indicates that they can be open or partially or completely mineralized. If cementation with secondary minerals is complete, the recovery of hydrocarbons will be generally very small because hydrocarbons will not have any way to move from matrix to natural fracture and then to the wellbore. However, if secondary mineralization is partial, production rates and recoveries could be quite significant because the secondary minerals would play the role of natural proppant agents helping to maintain the fractures open as the reservoir is depleted. If the fractures are initially open, production rates and recoveries could be large or small depending on the relative orientation of the natural fractures with respect to in-situ stresses. These observations lead to the key objective of this paper: to develop an analytical dual-porosity model using resistance networks for quantifying petrophysical fracture parameters such as degree of cementation (β), formation factor (F), dual-porosity exponent (m), and tortuosity (τ) for different degrees of mineralization (cementation) within the fractures. The method further allows estimating matrix and fracture porosities and fracture compressibility on the basis of the amount of secondary mineralization. Use of the new dual-porosity model is explained with two core data sets drawn from tight gas formations in the United States and Canada. A comparison is made with results of current dual-porosity models that do not take into account secondary mineralization within the natural fractures and tortuosity. The conclusion is reached that the proposed dual-porosity model provides a valuable new quantitative tool for petrophysical and reservoir-engineering evaluations of naturally fractured reservoirs. This is illustrated with two numerical examples that show determination of original petroleum in place and recovery. One example is volumetric, and the other one is based on the material-balance calculations.

Process modeling of direct coal-biomass to liquids (CBTL) plants with shale gas utilization and CO2 capture and storage (CCS)

Direct coal liquefaction (DCL) technologies have been commercially demonstrated for producing transportation fuels from non-petroleum sources. However, significant amount of hydrogen is required in the DCL process due to the low H/C ratio in coal. As a result, DCL processes are usually associated with a high level CO2 emission from hydrogen production units. Hence, direct coal biomass to liquids (CBTL) processes with CO2 capture and storage (CCS) and shale gas utilization are proposed in this work as an option for reducing CO2 emission. In this study, the focus is on process simulation and calculation of material and energy balances of novel direct CBTL plants, which can be used as a basis for further studies, such as optimization, techno-economic analysis and life-cycle analysis. In this process, coal with moderate amount of biomass is converted into syncrude through reaction with H-donor solvent and gaseous hydrogen in a catalytic two-stage liquefaction unit. Hydrogen required for the liquefaction and product upgrading unit is produced from the liquefaction residue partial oxidation unit and the shale gas steam reforming unit or from the coal/biomass/residue co-gasification unit. Different CCS technologies are evaluated to achieve 90% overall carbon capture if high extent of CO2 capture is considered. Results of individual plant sections are validated with the existing data, if available. Sensitivity studies have been conducted to analyze the effects of key operating parameters and design parameters, such as the sources of hydrogen, CCS technologies, extent of CCS, and biomass/coal ratio. Key measures studied in this work include the fuel yield, thermal efficiency, CCS penalty and CO2 emission.

The multivariate calculation of material balances of flowsheets for separating ternary mixtures of different physical-chemical nature

An approach to the determination of free variables required for calculating the material balance of the flowsheet of ternary mixtures separation is presented. Phase diagrams of the considered ternary systems are characterized by the presence of a two-phase splitting area and by the presence of different amounts of azeotropes (classes 3.1.0, 3.1.1, 3.2.1 and 3.3.1). For all the systems flowsheets containing three rectification columns and a florentine vessel for separation were suggested. The multivariance of the solution of the balance problem was shown. The approach was illustrated by the example of real ternary systems characterized by different phase diagrams (methanol - chloroform - water, butyl alcohol - water - toluene, nitromethane - hexane - water). The parameters of the rectification columns were presented.

Transboundary transport of anthropogenic sulfur in PM2.5 at a coastal site in the Sea of Japan as studied by sulfur isotopic ratio measurement

Sulfur isotopic ratios (δ34S) in size separated aerosol particles (PM2.5 and coarse particles) were measured at Niigata-Maki facing the Sea of Japan. Non-sea salt δ34S (δ34Snss) in PM2.5 showed seasonal variations with relatively high values in winter (1.0–3.9‰ in spring, 2.8–4.5‰ in summer, 1.3–4.5‰ in autumn, 3.7–5.7‰ in winter). Taking into consideration air mass transport routes, δ34Snss in the air masses which originated in the Asian continent and were transported over the Sea of Japan to the monitoring sites were higher than those values for air masses which were transported over the Japanese islands after leaving the Asian continent for each season. Considering that the δ34Snss in sulfuric acid derived from domestic emissions in Japan are lower than those of δ34Snss in coal, the lower δ34Snss for the air mass transported over the Japanese islands suggest that sulfuric acid in PM2.5 modified the δ34Snss due to aerosol mixing with sulfuric acid in Japan. Material balance calculations suggested that the relative contribution of transboundary transport in winter was also higher than for other seasons (40–75% in spring, 51–63% in summer, 45–73% in autumn, and 53–81% in winter). In particular, the contribution to the air masses which were transported directly from the Asian continent was relatively large (75% in spring, 59% in autumn, 78% in winter) in comparison with that for the air masses which were transported over Japan.

PVT correlations for Pakistani crude oils using artificial neural network

Reservoir fluid properties such as bubble point pressure, oil formation volume factor and viscosity are very important in reservoir and petroleum production engineering computations such as outflow–inflow well performance, material balance calculations, well test analysis, reserve estimates, and numerical reservoir simulations. Ideally, these properties should be obtained from actual measurements. Quite often, however, these measurements are either not available or very costly to obtain. In such cases, empirically derived correlations are used to predict the needed properties using the known properties such as temperature, specific gravity of oil and gas, and gas–oil ratio. Therefore, all computations depend on the accuracy of the correlations used for predicting the fluid properties. Almost all of these previous correlations were developed with linear or nonlinear multiple regression or graphical techniques. Artificial neural networks, once successfully trained, offer an alternative way to obtain reliable and more accurate results for the determination of crude oil PVT properties, because it can capture highly nonlinear behavior and relationship between the input and output data as compared to linear and nonlinear regression techniques. In this study, we present neural network-based models for the prediction of PVT properties of crude oils from Pakistan. The data on which the networks were trained and tested contain 166 data sets from 22 different crude oil samples and used in developing PVT models for Pakistan crude oils. The developed neural network models are able to predict the bubble point pressure, oil formation volume factor and viscosity as a function of the solution gas–oil ratio, gas specific gravity, oil specific gravity, and temperature. A detailed comparison between the results predicted by the neural network models and those predicted by other previously published correlations shows that the developed neural network models outperform most other existing correlations by giving significantly lower values of average absolute relative error for the bubble point, oil formation volume factor at bubble point, and gas-saturated oil viscosity.

Obtaining a fish minced feed by the method of cryoextrusion from frozen fish raw materials

Developed the technology of obtaining a fish minced feed (cryo minced fish feed) by the method of cryoextrusion using by the utility model extrusion of a piston-type cold working bodies for grinding the fish raw material in a frozen state. Justified the possibility of replacement in the standard technology of production the feed from the minced fish such technological operations as the defrosting and subsequent grinding of raw materials to the operation like a cold extrusion or cryoextrusion. Used the shape of the holes of the die for forcing the raw material in the form of “hourglass” with a diameter of 7 mm, the length of the process of pushing – 40 seconds. Determine the actual losses of raw material in the milling process meth of cryoextrusion ranging from 1% to 2.5%, including the losses when cutting block for the preparation of raw materials to piercing. It is established that the finished product – cryo minced fish feed, has a homogeneous grinding, juicy, crumbly texture, the temperature in the thickness of the product is not changed and equal to the temperature of raw materials before processing, that is minus 18 °C. Developed the principal technological scheme of obtaining the cryo minced fish feed by the method of cryoextrusion. The calculation of material balance in the production of beef has shown that the use of the new method will allow to increase the product yield up to 99%. Based on the studies of the chemical composition of fish and feed of mince obtained by traditional and developed methods established that the protein content in the cryo minced fish feed remains unchanged. Developed draft technical specifications for the production of cryo minced fish feed and technological instructions for the production of cryo minced fish feed for fodder purposes, and also prepared the application for the patent named “Obtaining cryo minced fish feed from the frozen fish by the method of cryoextrusion”.

New PVT Correlations Based on Libyan Crudes for Predicting Fluid Physical Properties

PVT properties are very important in reservoir and production engineering analyses such as material balance calculations, well testing, reserve estimation, inflow performance, production operations and design of surface facilities. New empirical PVT correlations have been developed for Libyan crudes with reliable degree of accuracy. These include; bubble point pressure (Pb), oil formation volume factor (Bo), gas solubility (Rs), stock tank oil molecular weight (Mwt), dead oil viscosity (μod), saturated oil viscosity (μob), under-saturated oil viscosity (μo), and oil compressibility (Co). Around 300 PVT samples collected exclusively from Libya, mainly Sirte, Ghadames and Murzuq basins, were used in our study to develop the above PVT correlations and covered wide range of API gravity (26 to 51°API) and reservoir temperature (100 to 313°F) normally found in Libyan reservoirs. Minitab regression tool was extensively used in our study to develop the PVT correlations and to statistically appraise them against the industry published correlations. The new proposed PVT correlations have demonstrated much better performance compared to the industry published correlations when tested for Libyan crudes. Also, Artificial Neural Network (ANN) models have been developed for Libyan PVT properties predictions. The models show acceptable accuracy and generally are more accurate than the empirical correlations.

Dynamic Material Balance Study of Gas Reservoir Using Production Data: A Case Study of New Gas Sand of Kailashtila Gas Field

The material balance is one of the fundamental practice in reservoir engineering and is considered as a reliable estimation of hydrocarbons-in-place. A good knowledge of average reservoir pressure is essential to determine original gas-in-place. To have such reservoir pressure, the well needs to be shut-in for few days to months, resulting in loss of production. In the current economic environment, this production loss is often unexpected. In a previous study, Matter and McNeil showed that material balance calculation could be done without shut-in well, which uses flowing well pressure instead of static pressure and constant flow rates. However, a constant production rate for an extended period of time is very challenging production criterion for the majority gas fields. The dynamic material balance is an extension of the flowing material balance that allows either constant or variable flow rate. This study describes the practical application of a method known as Dynamic Material Balance for average reservoir pressure determination using flowing pressures and variable production rates and thus to estimate the original gas-in-place of new gas sand of Kailashtila Gas Field. The main purpose of this study is to apply the method in field cases and to make a comparison with other standard methods of reserve estimation such as volumetric, type curve analysis to see the result and validate the efficiency of its application. These comparisons show a fairly good agreement in gas in place obtained from the dynamic material balance method and that of type curve analysis in this field.

포트 재배에 의한 화약물질 오염토양 정화용 내오염성 식물 선정

ABSTRACT Nine plant species were selected through vegetation survey at three military shooting ranges at northern Gyeonggi Province.Plants were germinated in normal soil and three seedlings were transplanted to a bottom sealed pot containing sandy loamsoils contaminated with either RDX (291 mg/kg) or TNT (207 mg/kg). Planted, blank (without plant), and control (withoutexplosive compound) pots were grown in triplicate at a green house for 134 days. During cultivation, transplanted plantsexhibited chlorosis and necrosis in flower and leaf by explosive toxicity and stress. Only three plants, Wild soybean, Amursilver grass, Reed canary grass, survived in TNT treated pot, while seven plant species except for field penny cress andjimson weed, thrived in RDX treated pot. Appreciable amount of TNT (61.6~241.2 mg/g-D.W.) was detected only in plantroots. Up to 763.3 mg/g-D.W. along with 4-amino-2,6-dinitrotoluene, an intermediate of TNT, accumulated in the root ofwild soybean. In addition, azoxy compounds, abiotic intermediates of TNT, were detected in TNT treated soils. RDXabsorbed average 1,839.95 mg/kg in shoot and 204.83 mg/kg in root. Most of TNT in plant was accumulated in undergroundpart whereas RDX was localized in aerial part. Material balance calculation showed that more than 95% of the initial TNTwas removed in the planted pots whereas only 60% was removed in the blank pot. The amount of RDX removed fromsoil was in the order of Amur Silver Grass (51%) > Chickweed (43%) > Evening primrose (38%). Based on the results ofpot cultures, Amur silver grass and Reed canary grass are selected as tolerant remedial plants for explosive toxicity.Key words : Pot culture, Phytoremediation, RDX, TNT, Toxicity

Analyzing variable-rate flow in volumetric oil reservoirs

Abstract Estimating average-reservoir pressure ( p av ) and its evolution with time is critical to analyzing and optimizing reservoir performance. Normally, selected wells are shut in periodically for buildup tests to determine p av over time. Unfortunately, shutting-in wells leads to loss of production. Today, however, real-time surveillance—the continuous measurement of flowing pressures and rate data from the oil and gas wells—offers an attractive alternative technique to obtain average-reservoir pressure while avoiding loss of revenue. A direct method for estimating p av from flowing pressures and rate data is available. However, the method is for an idealized case that assumes constant production rate during pseudosteady-state (PSS) flow, which is generally untrue for real wells. This paper extends that approach so that it can be used to analyze field data with variable rates/variable pressures during boundary-dominated flow (BDF). This approach is based on a combination of rate-normalized pressure and superposition-time function. The mathematical basis is presented in support of this approach, and the method is validated with synthetic examples and verified with field data. This modified approach is used to estimate average-reservoir pressure that uses flowing pressures and production rates during BDF, allowing the classical material balance calculations to be performed. These calculations, in turn help determine the reserves, recovery factor, and reservoir drive mechanisms, allowing the reservoir performance and management to be properly evaluated. Furthermore, this method can be used to calculate both connected oil volume and reservoir drainage area as a function of time. Finally, this approach provides a reasonable estimation of the reservoir's shape factor.

Rapid method for the determination of solution gas-oil ratios of petroleum reservoir fluids

Accurate determination of pressure-volume-temperature (PVT) properties of petroleum reservoirs is essential in material balance calculations, inflow performance, well-test analysis, reservoir simulation, etc. Ideally, those data should be obtained experimentally; however, experimental measurements require accurate and enough sampling, and are time consuming, expensive and tedious. Therefore, seeking for a simple, reliable and accurate model for prediction of PVT properties of petroleum systems is of a vital importance. In this communication, a large PVT data bank, covering a wide range of thermodynamic conditions was collected from variety of geographical locations around the world. Afterward, gene expression programming (GEP) was employed to develop a universal model for solution gas: oil ratio. The proposed model is a function of bubble point pressure, gas specific gravity, and oil API gravity, and has a very simple format with only one tuning parameter. The proposed model was compared to both explicit and implicit models available in literature for prediction of solution gas: oil ratio, using statistical and graphical error analyses. The results of this study indicate that the proposed model is more accurate, reliable and efficient compared to all other published correlations.

Report on the Evaluation of Ugua J2 and J3 Reservoir Performance

Globally, there are different techniques applied in the industry such as analog, volumetric, decline curve, material balance and simulation methods to estimate hydrocarbon reserves which depends upon the volume and quality of available data with some levels of uncertainties. The analogy method is applied by comparing factors for the current fields or wells while the volumetric method implies the determination of the extent of the reservoir, pore volume of the reservoir rock and the content of fluid within the reservoir pore volume when production and pressure data from field become available, decline curve analysis and material balance calculations become the predominant methods of calculating reserves since the hydrocarbon reserve estimates is a continuous process for a field that is producing. This study presents a report on the material analysis of Ugua J2 and J3 reservoirs with MBAL prior to the field’s dynamic reservoir simulation. The available data were validated and the analytical plot of pressure and production data indicated that J2 and J3 reservoirs are communicating. Hence multi-tank material balance analysis approach linked with transmissibility was adopted to model the reservoirs. The Hurst-Van Everdingen radial aquifer model was selected as the most likely case. The oil initially in place value obtained for J2 and J3 are 125.006 and 80.689 MMstb.

Development modes of Triassic Yanchang Formation Chang 7 Member tight oil in Ordos Basin, NW China

Abstract The Triassic Yanchang Formation Chang7 Member tight oil reservoir in Ordos Basin, featuring complex pore-throat structures, low porosity, low permeability, rich micro-fractures and low pressure coefficient, is difficult to produce by advanced water-flooding from cluster vertical wells with low individual-well producing rate. With Block A as an example, the material balance calculation, numerical simulation and field practical analysis showed that the horizontal well production would increase significantly using volumetric fracturing. But the well pattern of water injection in vertical wells and oil production in horizontal wells has high risk of injection water breakthrough in horizontal wells, and the proportion of water breakthrough wells reached 65%. In contrast, the formation energy decreased in depletion development with horizontal wells, in which the oil production kept stable in early period, but decreased quickly after 12 months, the cumulative decline of oil rate in 4 months amounted to 50.3%. Therefore, a development scheme of depletion production from volumetric fracturing horizontal wells at first and then water-flooding huff and puff after producing energy is deficient was proposed. Following this scheme, the daily oil rate of single well increased by 78.3% after the first cycle of water huff-and-puff than before the treatment, marking the initial success of the measure.

Investigation of the well performance in shared gas fields

The evaluation of well deliverability and gas migration is one of the most prominent challenges of shared fields. These fields are under production by two or more countries, in which normally only data of internal (domestic) part is available and there is a lack of data availability for production of external (foreign) part. Moreover, the basic assumption under most of the well performance models is constant drainage area, which, in fact, is not the actual case. Therefore, this study was aimed at presenting an analytical well performance method, accounting for the non-volumetric effects in the internal region of a shared reservoir. Consequently, the proposed method was used to estimate gas migration, production profile of external region and material balance calculation in shared reservoirs. In so doing, a new dynamic material balance equation was introduced to calculate the average field pressure through evaluating internal wells deliverability. It was noted that data of the external region is not needed in this study. The results of this analytical approach were compared against numerical modeling, and it was found that both models are in close agreement and as a result, proved the accuracy of the method within the typical ranges of rock and fluid parameters of gas reservoirs. • Variable common boundary is observed in shared fields. • The amount of gas migration is calculated through wells deliverability of internal region. • New pseudo-time and dynamic material balance models are performed. • Having a relationship between both regions is required for performance analysis.

PROCESS DESIGN FEATURES OF A 5 TONNES/DAY MULTI – STAGE, INTERMITTENT DRAINAGE, CONTINUOUS FULL IMMERSION, VEGETABLE OIL SOLVENT EXTRACTION PLANT

In this work, the process design features of a seven stage pilot extraction plant for use in vegetable oil extraction are presented. Three local oils were used in the study. They were Palm oil, Palm Kernel oil and Soy-bean oil. However PKO was used as a case study in the design because it is a simple oil with properties falling between those of palm oil and Soyabean oil. Material and Energy balance calculations were established for the oil as a base of mechanical design of part II. Nhexane was used as a leaching solvent. The efficiency of the plant was found to be 0.70. Process design calculations gave 23.17Kj as the energy requirement of the extractor based on a capacity of approximately 1 Kg of oil extract. The diffusivity of the oils in the solvent averaged 4.0 x 10 m/s, while the rate of mass transfer into the solvent was 6.47 x 10 Kmole/m. s, resulting in a mass transfer coefficient of 3.2 x 10Kmole/m. s. ----------------------------------------------------------------------***-------------------------------------------------------------------

Influence of Gas-Gas Heater on Wet Flue Gas Desulfuration

Material balance calculation was adopted to a wet flue gas desulfurization (WFGD) system for exploring impacts of gas-gas heater (GGH). Effects of GGH on flue and water consumption were analyzed. Results showed that inlet flue temperature of desulfurization tower reduced by 3.4 °C at 100% load after installation of GGH. Exhausted gas temperature of system increased by 34.9°C. The heat release of original flue in desulfurization tower reduced by 43.72%. Plume rise height was significantly improved. Water evaporation in desulfurization tower declined by 42.07%.Amount of addendum water reduced by 39.06%, and water vapor carried by flue decreased by 19.78% at the outlet of WFGD. Therefore, operation condition of flue emission is improved and water consumption decreases with GGH.