Bottom Production Research Articles

Seasonal sea ice persisted through the Holocene Thermal Maximum at 80\xb0N

The cryospheric response to climatic warming responsible for recent Arctic sea ice decline can be elucidated using marine geological archives which offer an important long-term perspective. The Holocene Thermal Maximum, between 10 and 6 thousand years ago, provides an opportunity to investigate sea ice during a warmer-than-present interval. Here we use organic biomarkers and benthic foraminiferal stable isotope data from two sediment cores in the northernmost Barents Sea (>80 °N) to reconstruct seasonal sea ice between 11.7 and 9.1 thousand years ago. We identify the continued persistence of sea-ice biomarkers which suggest spring sea ice concentrations as high as 55%. During the same period, high foraminiferal oxygen stable isotopes and elevated phytoplankton biomarker concentrations indicate the influence of warm Atlantic-derived bottom water and peak biological productivity, respectively. We conclude that seasonal sea ice persisted in the northern Barents Sea during the Holocene Thermal Maximum, despite warmer-than-present conditions and Atlantic Water inflow.

QCD evolution of the gluon Sivers function in heavy flavor dijet production at the Electron-Ion Collider

Using Soft-Collinear Effective Theory, we develop the transverse-momentum-dependent factorization formalism for heavy flavor dijet production in polarized-proton-electron collisions. We consider heavy flavor mass corrections in the collinear-soft and jet functions, as well as the associated evolution equations. Using this formalism, we generate a prediction for the gluon Sivers asymmetry for charm and bottom dijet production at the future Electron-Ion Collider. Furthermore, we compare theoretical predictions with and without the inclusion of finite quark masses. We find that the heavy flavor mass effects can give sizable corrections to the predicted asymmetry.

Production of high octane gasoline by catalytic cracking of petroleum gasoil with palm’s triglyceride and oleic acid

The use of gasoline with appropriate octane number will affect directly to meet superfine engine performance and avoiding from knocking effect. Improvement of gasoline quality in fluid catalytic cracking process usually is achieved by replacement of new catalyst which needs higher production cost. This research work aimed to describe the alternative method for improving gasoline octane in catalytic cracking by means of feedstock modification using mixture of vacuum gasoil and few of palm’s triglyceride and oleic acid. The experimental work of cracking reaction was performed in a fluid-bed reactor of ACE unit using REY zeolite catalysts at temperature of 530 °C and catalyst-oil ratio of 5.5 g/g. The liquid product was analyzed by a gas chromatograph of simulated distillation to determine yields of gasoline, light cycle oil and bottom product continued by a gas chromatograph of detailed hydrocarbon analysis to obtain hydrocarbon composition and calculated research octane number of gasoline. Analysis of gaseous product was performed using a gas chromatograph of refinery gas analyzer to detect yields of dry gas and LPG, whereas coke deposited on spent catalyst was analyzed using the infra-red method. From the research work, it was found that feedstock prepared from vacuum gasoil added with 5 % refined bleached deodorized palm oil and oleic acid (9:1) had increased gasoline RON from 91.8 to 98.2. The improvement of gasoline octane was contributed by the presence of double-bond fatty acid that triggered promoting effect to aromatisation and hydrogen transfer reactions in the formation of more iso-paraffins, olefins and aromatics in gasoline.

Development of a restraining wall and screw-extractor discharge system for continuous jig separation of mixed plastics

Batch and continuous jig experiments were compared using plastic mixtures with different light and heavy particle ratios. The purity of bottom layer products of continuous jig was lower than those of batch jig because of light particle entrainment induced by the screw-type extractor. To minimize entrainment, a new discharge system consisting of a vertical restraining wall and a screw-type extractor was developed. The restraining wall was installed close to the “product-end” to separate the jig chamber into two and allow particles to transfer from one part to the other via the gap under the wall. The experimental results showed that this proposed discharge system could improve the purity of heavy particles in bottom layer products because of two reasons: (1) higher material mass ratio of heavy plastic close to product-end, and (2) changes in the flow of water and particles. Moreover, the purity of bottom layer products during continuous jig separation was influenced by the difference of material mass ratio in feed; that is, purity was higher when the ratio of heavy plastic was high. In addition, an estimation procedure based on multi-step treatment using separation curves is proposed to achieve the target purity of bottom layer products.

Forging Process Flow Development for Plate Production

Developed on the basis of the pilot and industrial work results, a process flow for the production of mono-block plates with 7600x7600x360 mm dimensions from a 290-ton ingot for subsequent 15H2NMFA steel bottom stamping, was carried out. A practical implementation of the developed procedure for the bottom production from mono-block large-sized plates was made. The basic technology for the mono-block plate production was applied in the conditions of Izhorskiye Zavody, OJSC and Atommash, OJSC, this technology provides for a minimum amount of reconstruction of the existing facilities of these enterprises.

Thermodynamics of formation and evaporation of lead-tin alloys

Only a few works have been devoted to thermodynamic studies of the lead-tin system by methods including the volatile components evaporation process. When the binary system is separated into metals by distillation, the volatile component is removed from the alloy and the low-volatile component accumulates in the bottom products, that is, there are alloy composition changes over the entire concentration range. It is necessary to know the boundaries position of the melt and vapor coexistence fields on the state diagram, especially for solutions beneficiated with non-volatile metal to assess the quality of the vapor phase by the content of the low-volatile component. In this regard, the study has been completed with the purpose to clarify the values of the thermodynamic functions of the formation and evaporation of lead-tin melts required to calculate the boundaries of the liquid and vapor coexistence fields on the state diagram that enables us to judge the amount of a low-volatile component in the vapor phase under equilibrium conditions. The thermodynamic activity of lead was calculated, as well as the numerical integration of the Gibbs-Duhem equation using the substitution proposed by Darken is the thermodynamic activity and pressure of saturated tin vapor Based on the values of the saturated lead vapor pressure, determined by the boiling point method (isothermal version) for alloys predominantly of the lead edge of the phase diagram. The thermodynamic constants thus obtained will add to the base of physicochemical data and will be used to calculate the boundaries of the vapor-liquid equilibrium fields on the phase diagram, allowing to determine the possibility and completeness of the distillation separation of metals.

Evaluating the possibility of high-pressure desorption of CO2 via volatile co-solvent injection

This work evaluates the possibility of employing a volatile co-solvent injection for recovering CO2 from loaded monoethanolamine at 120 °C under pressures above those achievable through regular desorption processes. This co-solvent would be fed directly into the reboiler, percolating the column and delivering higher operational pressures without significatively affecting the chemical equilibrium between CO2 and the amine. Removal of this co-solvent would be required before the lean amine is recirculated to the absorber. A shortcut methodology for screening possible co-solvent candidates is presented, and MESH calculations of hypothetical stripping processes employing the high-pressure desorption approach are performed to illustrate the expected behavior of these systems. Pressures above 500 kPa are theoretically obtainable through the use of co-solvents which are less volatile than CO2 but that are still gases at 25 °C and 101.325 kPa, such as isobutane and dimethyl ether. These co-solvents will leave the desorber fractioned between the distillate and the bottom product, thus requiring two additional separation process for recovery. Less volatile solvents will concentrate at the bottom stages of the desorber, while more volatile solvents will flow straight through the column all the way up to the distillate without effectively delivering pressures as high as desired. In other words, this methodology results in a delicate optimization problem of finding ideal volatilities and operational conditions. Though no detailed energy analysis is performed in this preliminary assessment, we have identified a promising opportunity for CO2 production at higher pressures and enumerated the issues one should be concerned with when looking further into high-pressure desorption.

Applicability of multivariate calibrations in atomic emission spectrometry with arc discharge

Recent achievements in the field of instrumental analytical chemistry are associated with the development of devices that register a variety of analytical signals and use a variety of information processing methods. Hence, the use of advanced mathematical techniques for the treatment of a large amount of data obtained is required. Multivariate approaches are of the greatest interest for the Earth and Life sciences since most studies are based on measuring the chemical composition of complex natural organomineral substances and describing their compositions, on which their properties directly depend. Natural objects are multidimensional in their origin, so several analysis methods and one-dimensional processing techniques are traditionally used for their study and analytical control in order to achieve the required accuracy of the results. The special mathematical techniques for processing the analytical signals in emission spectra objectively reduces costs while improving accuracy. The authors in the current paper attempt to assess the need for the use of multivariate calibrations in atomic emission spectrometry with arc discharge while simultaneously analyzing different types of objects. Different variants of calibrations are considered for two techniques of direct atomic emission determination of F as well as Li, P, B, Mn, Ni, Co, V, Cr, W, Mo, Sn, Ga, Pb, Cu, Zn, Ag, Sb, As, Tl, Ge, Bi and Cd (22 elements) in powders of rocks, loose and bottom sediments, soils, ashes, gold-silver ores and products of their processing.

Soft-sensor design for vacuum distillation bottom product penetration classification

Petroleum oil refineries are complex systems that convert crude into subproducts of value. The profit of the refinery depends on the quality of the resultant subproducts, which are usually determined by a laboratory analysis called “Needle penetration”. Normally, this laboratory analysis is costly and time-consuming since entails around four hours for its accomplishment. In order to solve this limitation, this paper proposes a novel soft-sensor design for online vacuum distillation bottom product penetration classification. The design of the soft-sensor is based on a new approach, the two-stage methodology, that considers the joint effect of both Normalization and Supervised Filter Feature Weighting methods to transform the features. This methodology stands on the analysis of the real impact of applying normalization methods on the contribution of each feature, providing results that significantly differ from the traditional premises of the state-of-the-art. The analysis includes the impact of normalization on distance metrics such as the Euclidean. Also, a new adaptation of Pearson correlation for the estimation of the feature weights respect to categorical labels is proposed in this work. Once the features are transformed, five well-known Machine Learning (ML) algorithms (K-means, K-NN, RFc, SVC and MLP) are considered for the design of the soft-sensor. The final soft-sensor design is selected based on the feature space transformation strategy and the ML algorithm that achieves the best results in terms of: accuracy, precision, generalization and explicability. In order to validate the proposal, real monitored data from a petroleum refinery plant sited in The Basque Country is employed. Results show that the proposed two-stage methodology improves the results obtained by the Normalization methods.

A port-stream based equation oriented modelling of complex distillation column: A dividing wall column case study

Dividing wall column (DWC) offers higher degree of freedom in comparison with the conventional column. Furthermore, the different sections configurations within the column are highly interacting with several recycle loops. Facing with such complex unit operation, describing its behaviour encourages the focal point on the resolution of ideal modelling approaches. Equation oriented (EO) modelling of DWC has been studied by several researchers involving complex algorithm and methodology. In this work, a new approach for modelling of DWC is presented. The modelling methodology involves variables connectivity based on ports and streams that is admissible to equation-oriented flow sheet. To verify the functionality of the proposed method, the modelled DWC is validated with two case studies depicted from experimental literature data to separate alcohol mixture and fatty acid fractionation. The model development was performed in MOSAIC, a web-based modelling tool and run in gPROMS. The model shows good convergence and has less than 10% error when compared to the above mentioned case studies. To furthermore extend the model capability, relative gain array (RGA) analysis was conducted for the fatty acid fractionation to determine the best control configuration in DWC. Result shows that L-S-V and L-S-B configurations are the best control configurations. Our analysis also shows that reflux flowrate, side flowrate and vapor boilup are best to control distillate product, side product and bottom product, respectively.

Parametric Sensitivity Analysis of the Separation Process for N-Butanol Production

n-butanol and iso-butanol are commonly produced by the hydrogenation of n-butyraldehyde and iso-butyraldehyde employing the patented copper catalyst accommodated in the reactors in series. The main cause of the lower n-butanol and iso-butanol yield was due to the catalyst blockage rendering a pressure build-up that could lead to a plant shut down. Bypassing the last reactor from the series could be a potential solution to continue running the plant until the next shutdown plan to replace catalyst. The study adopted simulation approach using Aspen Plus V10 to investigate the effect of bypassing the last reactor in the series to the product purity of the downstream separation processes. The iso-butanol and n-butanol with the desired purity were produced from the distillate and bottom product when the column was operated at the RR of 8.03 and DF of 0.328. The reaction conversion of R-102 was varied from 0.1-0.995 but the variation did not significantly change the composition of the main product. Hence, the present study affirmed that the bypassing of third reactor from the reactor train would not affect the product purity of the main product, n-butanol.

Kinetics study and process simulation of reactive distillation for the synthesis of ε‐caprolactone

AbstractA novel three‐stage catalytic reactive distillation (RD) column integrated chemical reaction and distillation process for the continuous synthesis of ε‐caprolactone (ε‐CL) was proposed to overcome the disadvantages of previous batch processes. Reaction kinetics according to the two‐step indirect oxidation method was studied firstly, which was essential in reactor design and process optimization as well as lacking in the current literature. Kinetics models obtained by data fitting were tested by residual distribution and model statistics. And then, according to the thermodynamic characteristics and reaction kinetics of this process, a steady‐state simulation of RD column was carried out with the process simulator Aspen Plus. The influence of operation parameters was investigated on process performance. Under the optimal operating conditions, the conversion of cyclohexanone was 97%, and the mass fraction of ε‐CL in the bottom products was 62.31%. The simulation showed that RD column worked with excellent results in respect to conversion and product purity because of integrating the processes of chemical reaction and distillation.

Rate Decline Analysis of Horizontal Wells with Multiple Variable Conductivity and Uneven Distributed Fractures

In this paper, a new rate decline analysis model of horizontal wells with variable conductivity and uneven distribution of multiple fractures is proposed. By Laplace transformation, point source integration, and superposition principle, solutions of multiple infinite conductivity fractures in closed reservoirs are obtained. By coupling Fredholm integral equation of variable conductivity, linear equations of variable conductivity fractures in Laplace space are obtained. Gauss-Newton iteration, Duhamel convolution, and Stehfest numerical inversion method are used to obtain the bottom hole production solution. The accuracy of the results is verified by comparing with Eclipse software simulation. Then, the influence of some important reservoir and fracture parameters on the production is analyzed. The calculative results show that the smaller the fracture spacing is, the earlier the fracture begins to decline, the more the production will decrease; the change of different fracture length with the total fracture length unchanged has almost no effect on the production; the angle between fracture and x -axis has an important effect on the production; the smaller the angle between fracture and x -axis is, the stronger the interference between fractures is, the higher the production; the initial fracture conductivity affects the early production behavior, and the higher the initial fracture conductivity, the higher the production; the larger the fracture declines index, the lower the production, but the decreasing range gradually decreases with the increase of the decline index; the larger the reservoir drainage radius, the later the energy depletion stage, the higher the production. At last, a good fitting effect is obtained by fitting an example of oil field. The model proposed in this paper enriches the model base of rate decline analysis of fractured horizontal wells and lays a theoretical foundation for efficient development and practice of tight reservoirs.

Optimum process configuration for ETBE production based on TAC minimization

A new process configuration consisting of hybrid pervaporation (PV) (with series–parallel arrangement and recycle streams)–distillation column (DC) or reactive distillation (RD) with a hybrid feed splitting-heat integrated distillation column (HIDiC) – heat integration method was proposed to produce ETBE. To evaluate the performance of the proposed method, 92 different processes for producing ETBE by RD columns, pressure swing distillation, PV, liquid–liquid extraction column or their combinations were optimized and compared to the new configuration. The PV modules were placed in four sections: before the column, next to distillate, next to bottom product and next to side stream. All process parameters in DC or RD, PV and heat integration were considered optimization variables, and all variables were simultaneously optimized by a hybrid GA–PSO algorithm. The proposed configuration reduced TAC by at least 30% and a maximum of 62% compared with other process configurations. This can be attributed to the use of PV instead of distillation columns, series–parallel arrangement instead of series and parallel arrangements in the PV process to reduce energy consumption and membrane area and also the use of heat integration between internal DC flows and PV streams to eliminate the need for hot utility.

Dynamic behavior and control strategy of cryogenic distillation column for hydrogen isotope separation in CFETR

Cryogenic distillation is one of the key processes to separate and concentrate tritium in the tritium fuel cycle of fusion reactors. The dynamic behavior and control strategy of the cryogenic distillation column in China Fusion Engineering Test Reactor was investigated by Aspen Dynamics. Six control models were applied to resist the disturbance of feed flow or feed composition fluctuation during operation. The dynamic simulation results indicated that the control structure of cascade composition/temperature combined with reboiler duty/feed flow rate ratios had the best dynamic performance. When the feed flow fluctuated, the purities of the bottom and top products were maintained in 1.5 h and 4 h, respectively. When the feed composition fluctuated, the purities of the bottom and top products were maintained in 2.5 h and 4 h, respectively.

Concentration of mixed acid by electrodialysis for the intensification of absorption process in acrylic acid production

The absorption process in acrylic acid production was water-intensive. The concentration of acrylic acid before distillation process was low, which induced to large amount of wastewater and enormous energy consumption. In this work, a new method was proposed to concentrate the side stream of absorption column and thus increase the concentration in bottom product by electrodialysis. The influence of operating conditions on concentration rate and specific energy consumption were investigated by a laboratory-scale device. When the voltage drop was 1 V·cP −1 (1 cP=10 −3 Pa⋅S), flow velocity was 3 cm·s −1 and the temperature was 35 °C, the concentration rates of acrylic acid and acetic acid could be 203.3% and 156.6% in the continual-ED process. Based on the experimental data, the absorption process combined with ED was simulated, in which the diluted solution from ED process was used as spray water and the concentrated solution was feed back to the absorption column. The results shown that the flow rate of spray water was decreased by 37.1%, and the acrylic acid concentration at the bottom of the tower was increased by 4.56%. The ions exchange membranes before and after use 1200 h were tested by membrane surface morphology (scanning electron microscope), membrane chemical groups (infrared spectra), ion exchange capacity, and membrane area resistance, which indicated the membrane were stable in the acid system. This method provides new method for energy conservation and emission reduction in the traditional chemical industry. • The electrodialysis was used to concentrate the solution taken from absorption column in acrylic acid production. • The artificial solution contained acrylic acid and acetic acid was concentrated efficiently. • The flow of spray water decreased by 37.1% and the concentration increased by 4.56%. • The ion exchange membrane were stable after using 1200 h.

Simulation of Carbon Capture from Flue Gas of a Coal-fired Power Plant by a Three-bed Pressure Swing Adsorption Process

In order to reduce carbon dioxide emissions, pressure swing adsorption (PSA) process was studied to capture carbon dioxide from flue gas in a coal-fired power plant. Pressure swing adsorption features its low energy consumption, low investment, and simple operation. This study aims to capture carbon dioxide from flue gas by PSA process for at least 85 % CO2 purity and with the other stream of more than 90 % N2 purity. To validate the accuracy of the PSA simulation program, the extended Langmuir-Freundlich equation was adopted to fit measured equilibrium data to describe the adsorption equilibrium of adsorbent zeolite 13X. Next, the simulation study used the linear driving force model and compared the results of breakthrough curves and desorption curves between experiments and simulation to verify the accuracy of the mass transfer coefficient kLDF value in linear driving force model. The agreement between experimental data and the simulation results is good. Further, the simulation was verified with the 100-hour cyclic-steady-state experiment of the 3-bed 9-step PSA process studied. Flue gas after desulphurisation and water removal (13.5 % CO2, 86.5 % N2) of subcritical 1 kW coal-fired power plant was taken as feed to the designed 3-bed 9-step PSA process. To find the optimal operating conditions, the central composite design (CCD) was used. After analysis, optimal operating conditions were obtained to produce a bottom product at 89.20 % CO2 purity with 88.20 % recovery, and a top product at 98.49 % N2 purity with 93.56 % recovery. The mechanical energy consumption was estimated to be 1.17 – 1.41 GJ/t-CO2.

Isobutyl acetate by reactive distillation. Part III. Conceptual design, simulation and optimization

This work studies the conceptual design of a Reactive Distillation (RD) process for isobutyl acetate production by esterification of acetic acid and isobutanol. Static and reactive residue curve map analyses were used to assess RD feasibility, and to identify suitable operating conditions for industrial implementation. The maps were obtained using validated phase equilibria and reaction kinetic models by coupling Aspen plus V.10 and Python. Afterwards, conceptual design outputs were used for a rigorous simulation and optimization of the process. The obtained results indicate that pure isobutyl acetate cannot be obtained as pure product from the RD column as it is a saddle node. However, isobutyl acetate can be obtained as bottom product at enough purity to fulfil urethane grade specifications. A final reactive distillation configuration was developed enabling to obtain almost complete reactants conversion, with a molar composition of isobutyl acetate > 99 % wt. at the bottoms of the column. According to the optimal operating conditions, isobutyl acetate via RD can be produced under an energy intensity of 0.77 kW/kgIbAC, a mass intensity of 1.16 kgreactants/kgIbAC, a productivity of 328.7 kgIbAC/m3h, and a production cost of 0.98 USD/ kgIbAC.

A modularization method based on the triple bottom line and product desirability: A case study of a hydraulic product

The development of sustainable products is a process that is increasingly being studied and discussed by companies in the world today, where the concern with the material resources used throughout the chain of product transformation grows year after year, becoming a consideration for the preservation of the environment. In a scenario in which product modularization methods found in the literature do not take equally into account the economic, environmental and social dimensions of the Triple Bottom Line, as well as aspects related to product desirability by the customer, this article proposes a novel method for the modularization of products with an emphasis on the Triple Bottom Line, using as modularization criteria economic, environmental and social indicators. The method is divided into four steps: evaluate, decompose, format and integrate. The modularization process takes into account customer expectations, which are identified and classified using the Kano Model. The proposed method for sustainable modular design is relatively simple to apply, allowing information acquired by the company over time not to be lost. Also, based on the identified product desirability properties, priorities are established in the design of products in order to provide customer satisfaction, as well as his/her consideration of aspects related to sustainability. As a way to prove and observe the functionality of the method, it was applied to a product manufactured by a company of the metal-mechanic sector located in Southern Brazil.

Comparison of Complete Extractive and Azeotropic Distillation Processes for Anhydrous Ethanol Production Using Aspen Plus™ Simulator

Performance of the extractive and azeotropic distillation processes using ethylene glycol and cyclohexane as solvents, respectively, for anhydrous ethanol production, were investigated using 02 RadFrac columns each and solvent recycling streams via simulation in Aspen Plus™ Simulator. Both operate at 1 atm, and feed flow rate equals to 100 kmol.h-1 (ethanol – 0.896 and water – 0.104 in mole fractions at the azeotropic point). The NRTL-RK was the model used for extractive and azeotropic distillations. The anhydrous ethanol purity from top of the 1st column of the extractive distillation (22 stages) was 99.50 % (on a mole basis) and water with 99.20 % of purity at the top of the 2nd column. On the other hand, in the azeotropic distillation, the 1st column (30 stages) had a bottom product of anhydrous ethanol purity of 99.99 % and water with 99.99 % of purity in the 2nd column, also at the bottom. Both processes produced anhydrous ethanol with a high-grade purity required by the standard norms ASTM D4806, EN 15376, and ANP 36. However, the extractive distillation spent 1,928.2 kW in the reboilers against 4,680.3 kW in the azeotropic distillation, demonstrating extractive distillation is the most economical option. Consequently, the energy consumption is an essential analysis for choosing the type of distillation, when an azeotropic mixture needs a good separation task. Finally, the extractive distillation demonstrated to be much more competitive than azeotropic distillation for this type of mixture although azeotropic distillation obtained a higher purity of anhydrous ethanol.