scholarly journals Reconstruction of the hardware design for isopropylbenzene production for the production of ethylbenzene

2021 ◽  
Vol 83 (2) ◽  
pp. 184-190
Author(s):  
S. V. Popov ◽  
N. Y. Krymkin ◽  
O. V. Khabibrakhmanov ◽  
E. N. Papulovskikh
Keyword(s):  
Computational Experiment ◽  
Distillation Column ◽  
Hardware Design ◽  
Reaction Mass ◽  
Technological Scheme ◽  
Design Parameters ◽  
Alkylation Reaction ◽  
Stable Operation ◽  
Separation Unit ◽  
Distillation Columns

The hardware design of the rectification unit for the production of isopropylbenzene in the presence of the AlCl3 catalyst is considered, the use of which has a number of problems associated with its corrosiveness, rapid deactivation, the complexity of regeneration, etc. One of the possible solutions to the listed technological disadvantages is the use of heterogeneous zeolite-containing catalysts. In this case, during the reconstruction of the existing production of isopropylbenzene in the technological scheme of separation of alkylate, three rectification columns are released, which are expediently used to separate the alkylate of ethylbenzene production. To study the possibility of using the discharging distillation columns, a computational experiment was carried out using the Honeywell UniSim Design modeling system, in which a model of the alkylate separation unit for ethylbenzene production was formed. The NRTL method was used as a mathematical package for calculating the thermodynamic properties of the mixture components. As a result of modeling the operation of the alkylate separation unit for each distillation column, the optimal operating process parameters were obtained: pressure of the top and bottom of the column, reflux ratio, temperature profile along the height of the column. The calculated material balance of the technological scheme shows that in the first distillation column, complete separation of benzene from the alkylation reaction mass is achieved, the second column ensures the production of commercial ethylbenzene, and in the third column, a fairly clear separation of diethylbenzene from the remaining components of the mixture is obtained. The performed computational experiment showed that for the organization of the stable operation of the technological scheme for the separation of alkylate in the production of ethylbenzene, it is possible to use all the considered distillation columns without changing their design parameters at a load on the reaction mass of alkylation of about 60 t / h.

scholarly journals Refreshment topics II: Design of distillation columns

2006 ◽  
Vol 60 (3-4) ◽  
pp. 92-102
Author(s):  
Svetomir Milojevic ◽  
Dejan Skala
Keyword(s):  
Production Process ◽  
Distillation Column ◽  
Separation Process ◽  
Normal Operation ◽  
Distillation Unit ◽  
Design Parameters ◽  
Specific System ◽  
Variable Parameters ◽  
Distillation Columns ◽  
The Right

For distillation column design it is necessary to define all the variable parameters such as component concentrations in different streams temperatures, pressures, mass and energy flow, which are used to represent the separation process of some specific system. They are related to each other according to specific laws, and if the number of such parameters exceeds the number of their relationships, in order to solve a problem some of them must be specified in advance or some constraints assumed for the mass balance, the balance of energy, phase equilibria or chemical equilibria. Knowledge of specific elements which are the constituents of a distillation unit must be known to define the number of design parameters as well as some additional apparati also necessary to realize the distilation. Each separate apparatus might be designed and constructed only if all the necessary and variable parameters for such a unit are defined. This is the right route to solve a distilation unit in many different cases. The construction of some distillation unit requires very good knowledge of mass, heat and momentum transfer phenomena. Moreover, the designer needs to know which kind of apparatus will be used in the distillation unit to realize a specific production process. The most complicated apparatus in a rectification unit is the distillation column. Depending on the complexity of the separation process one, two or more columns are often used. Additional equipment are heat exchangers (reboilers, condensers, cooling systems, heaters), separators, tanks for reflux distribution, tanks and pumps for feed transportation, etc. Such equipment is connected by pipes and valves, and for the normal operation of a distillation unit other instruments for measuring the flow rate, temperature and pressure are also required. Problems which might arise during the determination and selection of such apparati and their number requires knowledge of the specific systems which must be separated. The experience of the designer and his creativity for proposing a solution for an industrial unit which enables optimal process operation accompanied with minimal energy consumption, as well as a small number of apparati, and minimal total length of pipes and number of instruments is always a valuable additional effect for minimal investment costs and an optimal production process.

scholarly journals Use of numerical modeling methods in desing of combined rectification column

2019 ◽  
Vol 298 ◽  
pp. 00070
Author(s):  
Ramilya Ibragimova ◽  
Vitaliy Afanasenko ◽  
Gleb Kudryavtsev ◽  
Denis Mazidullin
Keyword(s):  
Software Package ◽  
Distillation Column ◽  
Hydraulic Calculation ◽  
Stable Operation ◽  
Application Software ◽  
Rectification Column ◽  
Distillation Columns ◽  
Hydrodynamic Parameters ◽  
Contact Devices ◽  
Distant Part

The article is devoted to the study of methods for modeling the operation of rectification columns using the HYSIS application software package. Such studies are very important not only for design, but also for the functioning of existing industries. The article proposes to use for combining nozzle devices in the concentration part of the column, and plate-shaped structures in the distant part of the column for more efficient and stable operation of distillation columns. To determine the hydrodynamic parameters of the operation of distillation column, a technique of determining the range of stable loads and the position of the operating point inside or outside the range of stable loads was taken. A column model was constructed using the HYSYS software package for separating gas mixtures with various contact devices: sieve trays, Rashig ring nozzles. Experiments for the same type and combined contact devices were carried out and their comparison was carried out in terms of hydraulic calculation and operating range. As a result of experiments with the use of the HYSYS software package, it was shown that the combined arrangement of contact devices can provide a stable hydraulic mode, in contrast to the use of similar contact devices.

scholarly journals Integrated Multiscale Latent Variable Regression and Application to Distillation Columns

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
Muddu Madakyaru ◽  
Mohamed N. Nounou ◽  
Hazem N. Nounou
Keyword(s):  
Feature Extraction ◽  
Latent Variable ◽  
Prediction Accuracy ◽  
Distillation Column ◽  
Selection Criterion ◽  
Process Data ◽  
Distillation Columns ◽  
Latent Variable Regression ◽  
Multiscale Filtering ◽  
Modeling Algorithm

Proper control of distillation columns requires estimating some key variables that are challenging to measure online (such as compositions), which are usually estimated using inferential models. Commonly used inferential models include latent variable regression (LVR) techniques, such as principal component regression (PCR), partial least squares (PLS), and regularized canonical correlation analysis (RCCA). Unfortunately, measured practical data are usually contaminated with errors, which degrade the prediction abilities of inferential models. Therefore, noisy measurements need to be filtered to enhance the prediction accuracy of these models. Multiscale filtering has been shown to be a powerful feature extraction tool. In this work, the advantages of multiscale filtering are utilized to enhance the prediction accuracy of LVR models by developing an integrated multiscale LVR (IMSLVR) modeling algorithm that integrates modeling and feature extraction. The idea behind the IMSLVR modeling algorithm is to filter the process data at different decomposition levels, model the filtered data from each level, and then select the LVR model that optimizes a model selection criterion. The performance of the developed IMSLVR algorithm is illustrated using three examples, one using synthetic data, one using simulated distillation column data, and one using experimental packed bed distillation column data. All examples clearly demonstrate the effectiveness of the IMSLVR algorithm over the conventional methods.

scholarly journals USING EXERGY LOSS PROFILES AND ENTHALPY-TEMPERATURE PROFILES FOR THE EVALUATION OF THERMODYNAMIC EFFICIENCY IN DISTILLATION COLUMNS

2005 ◽  
Vol 4 (1) ◽  
pp. 76 ◽  
Author(s):  
S. H. B. Faria ◽  
R. J. Zemp
Keyword(s):  
Energy Balance ◽  
Distillation Column ◽  
Enthalpy Of Solution ◽  
Exergy Loss ◽  
Thermodynamic Efficiency ◽  
Consistency Test ◽  
Distillation Columns ◽  
Water Distillation ◽  
Ideal Solutions ◽  
Thermodynamic Excess

In this work the temperature-enthalpy profile and the exergy loss profile are used together to improve thermodynamic efficiency of distillation columns, by identifying possible benefits of using side exchangers. The method proposed is to compute the exergy loss profile and to analyse the distribution of the losses across the column stages. The present work aims at applying the stage-by-stage exergy analysis to the distillation of non-ideal mixtures, e.g. methanol/water. For these systems the use of thermodynamic excess properties is required: Gibbs free energy for phase equilibrium and enthalpy of solution for energy balance. Initial studies showed that the enthalpy of solution has a small effect on the overall energy balance of the distillation column, but a significant impact on the exergy loss profiles. Some profiles even showed a violation of the second law of thermodynamics, with entropy being destroyed on some stages, clearly indicating that a wrong approach to exergy calculation was being used.A model for exergy calculations of non-ideal solutions is presented. The exergy values so computed are then checked by a consistency test, using the reversible column profile. Finally, the exergy procedures are used to study a typical methanol/water distillation columns, where the exergy profiles are used to identify scope for intermediate heat exchange.

Modeling of PVA Modified Non-Woven for Submerged Membrane Bioreactor Treating Synthetic Wastewater

2011 ◽  
Vol 356-360 ◽  
pp. 1109-1117
Author(s):  
Chun Hua Zhang ◽  
Yu Ying Dong ◽  
Feng Jie Zhang
Keyword(s):  
Wastewater Treatment ◽  
Relative Error ◽  
Membrane Bioreactor ◽  
Synthetic Wastewater ◽  
Design Parameters ◽  
Stable Operation ◽  
Fouling Resistance ◽  
Submerged Membrane Bioreactor ◽  
Operation Conditions ◽  
The Relationship

In this study, a mathematical model has been developed for the submerged membrane bioreactor (SMBR). Polyvinyl alcohol (PVA) Modified Non-woven model is immerged in MBR to be used for synthetic wastewater treatment. The results show that membrane fouling resistance is mostly cake resistance occurring during filtration. Based on the concept of specific fouling resistance and Darcy law that describes the relationship between flux and resistance during filtration driven by pressure, a module is established to explain the relationship between specific fouling resistance and time during filtration controlled by cake resistance in SMBR. The decline trend of flux can be predicted by the model. The model is used to predict the decline trend of flux during pharmaceutical wastewater treatment. Compared with experimental data, the relative error is less than 10% at t>b, the relative error is less than 5% at t>2b. It shows that the model can predict the decline trend of flux during stable operation of SMBR. But the relative error is bigger during unstable operation at initial stage (t<b). The model developed in this study would provide a useful tool in optimizing operation conditions as well as design parameters for a SMBR system.

scholarly journals Design Requirements Substantiation for an Automated Planting Unit for Potato Minitubers

2021 ◽  
Vol 15 (1) ◽  
pp. 9-15
Author(s):  
A. S. Dorokhov ◽  
V. N. Zernov ◽  
S. N. Petukhov
Keyword(s):  
Technological Scheme ◽  
Smooth Transition ◽  
Design Parameters ◽  
Back Side ◽  
Roller Diameter ◽  
Original Seed ◽  
Type Device ◽  
Unit Speed ◽  
Guide Roller ◽  
Design Requirements

The authors showed that the transition to the technology of virus-free minitubers mass production changed the machines requirements for planting original seed potatoes.(Research purpose) To develop a technological scheme and substantiate the design parameters of the planting apparatus of an automatic planter of potato minitubers.(Materials and methods) The development was based on an elevator-type planting apparatus. The authors decided to create a spoon design with the ability to grip and move into the guide casing one minituber in each spoon, eliminating the minitubers jumping from one spoon to another or pinching them when moving along the guiding casing to the furrow bottom. The diameters of the lower guide and upper drive rollers were theoretically substantiated in order to exclude the influence of the planting tubers sizes difference on the uniformity of their submitting into the furrow.(Results and discussion) The authors determined the minimum permissible elevator belt speed, which depended on the distance between the spoons on the elevator belt and the planting unit speed. The size of the upper driving reel diameter was justified from the condition that the spoon unfolded 180 degrees in at least 1.5 seconds, which ensured a tuber smooth transition to the back side of the spoon.(Conclusions) The authors developed a technological scheme of an automatic planting elevator type device for planting potato minitubers with a working speed of 6-9 kilometers per hour. It was found that the upper driving reel diameter was not less than 44 centimeters, and the lower guide roller diameter was not more than 12 centimeters. They showed that the double-sided design of scooping spoons with the possibility of installing replaceable bowls in them would ensure a high-quality planting of not only minitubers, but also subsequent reproductions of seed and ware potatoes with a tuber mass of 5-80 grams.

scholarly journals SEMI-INDUSTRIAL TECHNOLOGY FOR SYNTHESIS OF 2-(1,3-DITHIOLAN-2-YLIDENE) MALONONITRILE

2020 ◽  
Vol 63 (4) ◽  
pp. 68-73
Author(s):  
Konstantin V. Lipin
Keyword(s):  
Raw Materials ◽  
Synthesis Method ◽  
Production Method ◽  
Reaction Mass ◽  
Technological Scheme ◽  
Technological Equipment ◽  
State University ◽  
Synthesis Time ◽  
Multi Stage ◽  
Short Synthesis

This article analyzes the developments of the scientific team of the Chemical and Pharmaceutical Faculty of Chuvash State University I.N. Ulyanov in the field of synthesis of 1,3-dithioheterocycles and based on them a method of synthesis of 2-(1,3-dithiolane-2-ylidene) malononitrile suitable for scaling was developed. The basis was chosen for the well-known three-component synthesis method, which has several disadvantages: the use of toxic and inaccessible reagents, multi-stage. During laboratory testing, this method of synthesis was improved. The developed method for producing 2-(1,3-dithiolane-2-ylidene)malononitrile consists of reacting malononitrile with carbon disulfide in the presence of potassium carbonate, adding dichloroethane to the resulting mixture, and boiling the mixture for 10-15 min. The final compound is isolated by diluting the reaction mass with water. Based on the developed method, a technological scheme for the synthesis of 2- (1,3-dithiolane-2-ylidene)malononitrile was compiled. The selected production method consists of four technological operations: mixing the starting components in the reactor, heating and boiling the reaction mixture, diluting the reaction mass with water and crystallizing the product, filtering 2-(1,3-dithiolane-2-ylidene)malononitrile. The first three stages can be carried out in one technological equipment - a reactor equipped with a stirrer and a jacket. For filtering it is necessary to use a nutsche filter. Based on the developed methodology, a technological scheme has been created, its description has been compiled. The design process capacity is 5 kg/h of 2-(1,3-dithiolane-2-ylidene)malononitrile. The necessary equipment is calculated. A standard mixing reactor with a volume of 0.1 m3 and a nutsche filter NFP-0.25-630 PP were selected. To mix the reaction mass, the reactor should be equipped with an anchor type mixer. The developed technology compares favorably with the use of simple and cheap raw materials common in the chemical industry, the short synthesis time and the use of standard technological equipment.

The influence of the design parameters of the milking machine collector on the oscillation of the vacuum pressure in the suction phase

2020 ◽  
pp. 117-123
Author(s):  
V. I. Achkevych ◽  
V. S. Khmelevsky ◽  
O. M. Achkevych
Keyword(s):  
Experimental Studies ◽  
Statistical Processing ◽  
Pressure Level ◽  
Vacuum Pressure ◽  
Design Parameters ◽  
Stable Operation ◽  
Structural Factors ◽  
Compression Phase ◽  
Theoretical Substantiation ◽  
Milking Machine

Annotation Purpose. Substantiation of design parameters of two-chamber collector of milking apparatus by stabilization of vacuum mode of milkline of milking apparatus. Methods. An analysis of the results of experimental studies was used, which were carried out in laboratory conditions using methods of planning multi-factor experiments and statistical processing of experimental data using appropriate software. Results. Based on the results of theoretical substantiation, a prototype of a two-chamber milking collector of a milking machine was made and experimental studies were carried out on with varying structural factors according to the intensity of milk breeding. The analysis of the results of the experimental studies indicates that the rational diameter of the milk hose is 12 mm, with a throttle hole of 2 mm. The use of the proposed two-chamber collector with a portion inlet of air in the milking machine allows us to stabilize the vacuum pressure in the sucking phase, as a result of which milk with low content of somatic cells is of the highest quality. Conclusions. It has been found that the stable operation of the milking machine provides a constant vacuum pressure in the sucking phase and a sufficient drop in the vacuum pressure in the compression phase. The appropriate pressure level will be maintained by combining the diameters of the milk hose 12 mm and the throttle opening 2 mm. Keywords: milking machine, vacuum pressure, milk-shaped hose, throttle hole, two-chamber collector.

ENERGY EFFICIENT DISTILLATION COLUMNS ANALYSIS FOR AN AROMATIC SEPARATION PROCESS

2016 ◽  
Vol 78 (3-2) ◽  
Author(s):  
Muhammad Zakwan Zaine ◽  
Mohd. Faris Mustafa ◽  
Onn Hassan ◽  
Kamarul Asri Ibrahim ◽  
Norazana Ibrahim ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Efficient ◽  
Driving Force ◽  
Energy Savings ◽  
Energy Analysis ◽  
Optimal Sequence ◽  
Separation Unit ◽  
Distillation Columns ◽  
Improve Energy Efficiency ◽  
Force Method

Energy savings is a major challenge in distillation operations. However, there is still one problem, which is how do we improve the energy efficiency of the existing distillation column systems without major modifications. Recently, a new energy efficient distillation columns methodology that will be able to improve energy efficiency of the existing separation systems without having major modifications has been developed. Therefore, the objective of this paper is to present a new improvement of the existing methodology by designing an optimal sequence of energy efficient distillation columns using a driving force method. Accordingly, the methodology is divided into four hierarchical sequential stages: i) existing sequence energy analysis, ii) optimal sequence determination, iii) optimal sequence energy analysis, and iv) energy comparison and economic analysis. The capability of this methodology is tested in designing an optimal synthesis of energy efficient distillation columns sequence of an aromatics separation unit. The existing aromatics separation unit consists of six compounds (Methylcyclopentane (MCP), Benzene, Methylcyclohexane (MCH), Toluene, m-Xylene and o-Xylene) with five direct sequence distillation columns being simulated using a simple and reliable short-cut method and rigorously tested within an Aspen HYSYS® simulation environment. The energy and economic analyses show that the optimal sequence determined by the driving force method has a better energy reduction with a total of 6.78% energy savings and a return of investment of 3.10 with a payback period of 4 months. It can be concluded that, the sequence determined by the driving force method is not only capable in reducing energy consumption, but also has a better economic cost for an aromatic separation unit

Sign in / Sign up

Export Citation Format

Share Document