[LAB REPORT]

by

[M.SULEMAN ARSHAD][Roll No 10-CH-46][Submitted TO: Sir Ayemen]

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TABLE OF CONTENTS

EXPERIMENT NO 1

SECTION 1.1SECTION 1.2SECTION 1.3

EXPERIMENT NO 2

SECTION 2.1SECTION 2.2SECTION 2.3

EXPERIMENT NO 3

SECTION 3.1SECTION 3.2SECTION 3.3EXPERIMENT NO 4SECTION 4.1SECTION 4.2SECTION 4.3

EXPERIMENT NO 5

SECTION 5.1SECTION 5.2SECTION 5.3EXPERIMENT NO 6SECTION 6.1SECTION 6.2SECTION 6.3

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EXPERIMENT NO 7

SECTION 7.1SECTION 7.2SECTION 7.3EXPERIMENT NO 8SECTION 8.1SECTION 8.2SECTION 8.3

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INTRODUCING ASPEN PLUS

Aspen Plus makes it easy to build and run a process simulation model by providing you with a comprehensive system of online prompts, hypertext help, and expert system guidance at every step. In many cases, you will be able to develop an Aspen plus process simulation model without referring to printed manuals.

The seven hands-on sessions show you, step-by-step, how to use the full power and scope of Aspen Plus. Each session requires 30 – 50 minutes.

WHY USE PROCESS SIMULATION?

Process simulation allows you to predict the behavior of a process by using basic engineering relationships, such as mass and energy balances, and phase and chemical equilibrium. Given reliable thermodynamic data, realistic operating conditions, and rigorous equipment models, you can simulate actual plant behavior.

Process simulation enables you to run many cases, conduct "what if" analyses, and perform sensitivity studies and optimization runs. With simulation, you can design better plants and increase profitability in existing plants.

Process simulation is useful throughout the entire lifecycle of a process, from research and development through process design to production.

A process consists of chemical components being mixed, separated, heated, cooled, and converted by unit operations. These components are transferred from unit to unit through process streams.

Idea Process Simulation

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WHAT IS AN ASPEN PLUS PROCESS SIMULATION MODEL?

You can translate a process into an Aspen Plus process simulation model by performing the following steps:

1 Define the process flowsheet: o Define the unit operations in the process. o Define the process streams that flow to and from the unit operations. o Select models from the Aspen Plus Model Library to describe each unit operation and place them on the process flowsheet. o Place labeled streams on the process flowsheet and connect them to the unit operation models.

2 Specify the chemical components in the process. You can take these components from the Aspen Plus databanks, or you can define them.

3 Specify thermodynamic models to represent the physical properties of the components and mixtures in the process. These models are built into Aspen Plus.

4 Specify the component flow rates and the thermodynamic conditions (for example, temperature and pressure) of feed streams.

5 Specify the operating conditions for the unit operation models.

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EXPERIMENT # 1

OBJECTIVE

INTRODUCTION TO THE GRAPHICAL USER INTERFACE OF THE SIMULATION SOFTWARE. (ASPEN PLUS 2006.5)

 GRAPHICAL USER INTERFACE:

A graphical user interface (GUI) is a human-computer interface i.e., a way for humans to interact with computers. It refers to the graphical interface of a computer that allows users to click and drag objects with a mouse instead of entering text at a command line. GUI allows users to interact with electronic devices through graphical icons and visual indicators. GUIs stand in sharp contrast to command line interfaces (CLIs). The most familiar example of a CLI to many people is MS-DOS.A major advantage of GUIs is that they make computer operation more intuitive, and thus easier to learn and use.

TOOL BARJust below the menu bar, Tool bar is located. This bar allows user quick access to a specific command using shortcut icons. Every icon materialized with the purpose to trigger a unique operation e.g. to set Physical property or to get into Setup menu directly by clicking just once.

STATUS BARStatus bar is located at most bottom of the flow sheet window. This shows the info about the work advancement through simulation. At most right corner, flowsheet completion or incompletion status is cited while adjacent to it, the left side, sheet location is referred. At most left side, help command F1 is marked to seek help during simulation work.

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MODEL LIBRARYModel library appears to be happening just above the status bar. This facilitates us to work in a specific equipment design worksheet that includes the entire commands and data library for simulation of concerned equipment.

THE WORKSPACE:The area in the middle of the screen is known as the workspace. This is the main focus of the Aspen window, the place where you’ll build and edit flow sheets, view graphs and run program. When you first launch Aspen, the workspace is white. When you start to build a flow sheet or open an existing simulation, the flow sheet displays in the workspace.

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MAIN MENU:

The main menu is located just under the title bar at the top of the program window. Some items on the main menu are common to nearly all Windows programs namely File Edit, Format, and Help. Other items are library, run, data.

STATUS AREA:

When flow sheet is completed, the status message changes from “Flow sheet Not Complete” to “Required Input Complete.” After providing all input data using input forms, the status bar shows “Required Input Complete” and then only simulation results are obtained.

STREAM BALANCE

Used to apply different type of balances across the equipment that includes Material Balance, Energy Balance and Work Balance.

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EXPERIMENT NO. 2

OBJECTIVE:-

TO SELECT THE COMPONENTS, MAKE A LIST AND PLOT 3 DIFFERENT PROPERTIES USING APEN(2006.5)

PROCEDURE:-

1. First of all I opened (Aspen 2006.5) explorer to open simulation bar from AspenExplorer and click on the component option then select the component and press2. After that I clicked on the component list and select the components (described).3. After selecting the component I clicked on the plot option then a window (plotproperty option) appear. I chose library liquid density, library liquid viscosity, libraryvapor pressure, library liquid heat capacity, library liquid thermal conductivity,library heat of vaporization to plot graph and study their behavior.

USING NRTL:-

PROPERTIES:-I am able to find vapor specific heat capacity of ammonia at constant pressure by this plot at any temperature above graph shows the Cp of ammonia in System international.

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Temperature Pressure CpK Atm j/kmol-k273 200 34897.67283.2041 200 35151.97293.4082 200 35423.07303.6122 200 35709.16313.8163 200 36008.36324.0204 200 36318.81334.2245 200 36638.72344.4286 200 36966.39354.6327 200 37300.24364.8367 200 37638.83375.0408 200 37980.87385.2449 200 38325.22395.449 200 38670.89405.6531 200 1643450000415.8571 200 148272426.0612 200 169084436.2653 200 181907446.4694 200 169314456.6735 200 142083466.8776 200 118978477.0816 200 102997487.2857 200 92101.55497.4898 200 84449.25507.6939 200 78882.31517.898 200 74703.56528.102 200 71483.93538.3061 200 68949.9548.5102 200 66920.72558.7143 200 65272.91568.9184 200 63919.63579.1224 200 62798.17589.3265 200 61862.23599.5306 200 61076.93609.7347 200 60415.52619.9388 200 59857.18630.1429 200 59385.45640.3469 200 58987.17650.551 200 58651.69660.7551 200 58370.29670.9592 200 58135.8681.1633 200 57942.23691.3673 200 57784.56701.5714 200 57658.54711.7755 200 57560.55721.9796 200 57487.49732.1837 200 57436.7742.3878 200 57405.84752.5918 200 57392.91762.7959 200 57396.12773 200 57413.93

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PROPERTIES:-I am able to find vapor specific heat capacity of ammonia at constant pressure by this plot at any temperature above graph shows the H of ammonia in System international.

Temperature Pressure Enthalpy(H)K Atm j/kmol273 200 -51612000283.2041 200 -51513000293.4082 200 -51424000303.6122 200 -51345000313.8163 200 -51278000324.0204 200 -51227000334.2245 200 -51193000344.4286 200 -51183000354.6327 200 -51203000364.8367 200 -51157000375.0408 200 -50899000385.2449 200 -50711000395.449 200 -50664000405.6531 200 -51489000415.8571 200 -55236000426.0612 200 -53617000436.2653 200 -51810000446.4694 200 -49996000456.6735 200 -48405000466.8776 200 -47080000477.0816 200 -45952000487.2857 200 -44961000497.4898 200 -44062000507.6939 200 -43230000517.898 200 -42447000528.102 200 -41702000538.3061 200 -40986000548.5102 200 -40293000

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558.7143 200 -39619000568.9184 200 -38960000579.1224 200 -38314000589.3265 200 -37678000599.5306 200 -37051000609.7347 200 -36431000619.9388 200 -35818000630.1429 200 -35209000640.3469 200 -34605000650.551 200 -34005000660.7551 200 -33408000670.9592 200 -32814000681.1633 200 -32222000691.3673 200 -31631000701.5714 200 -31042000711.7755 200 -30454000721.9796 200 -29867000732.1837 200 -29281000742.3878 200 -28695000752.5918 200 -28110000762.7959 200 -27524000773 200 -26938000

PROPERTIES:-I am able to find vapor specific heat capacity of ammonia at constant pressure by this plot at any temperature above graph shows the G of ammonia in System international.

temperature Pressure Free energyK Atm j/kmol273 200 -12384000283.2041 200 -10847000

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293.4082 200 -9308000303.6122 200 -7767000313.8163 200 -6222900324.0204 200 -4674700334.2245 200 -3121400344.4286 200 -1561600354.6327 200 6211.312364.8367 200 1595410375.0408 200 3215360385.2449 200 4837710395.449 200 6467820405.6531 200 8120470415.8571 200 10295900426.0612 200 11884600436.2653 200 13432200446.4694 200 14936900456.6735 200 16402300466.8776 200 17835300477.0816 200 19241500487.2857 200 20625200497.4898 200 21989100507.6939 200 23335300517.898 200 24665400528.102 200 25980300538.3061 200 27281200548.5102 200 28568700558.7143 200 29843500568.9184 200 31106100579.1224 200 32357000589.3265 200 33596700599.5306 200 34825400609.7347 200 36043500619.9388 200 37251200630.1429 200 38448900640.3469 200 39636800650.551 200 40815200660.7551 200 41984100670.9592 200 43143800681.1633 200 44294500691.3673 200 45436300701.5714 200 46569500711.7755 200 47694000721.9796 200 48810200732.1837 200 49918100742.3878 200 51017800752.5918 200 52109400762.7959 200 53193100773 200 54269000

PROPERTIES:- I am able to find vapor specific heat capacity of ammonia at constant pressure by this plot at any temperature above graph shows the S of ammonia in System international.

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Temperature Pressure Entropy(S)K Atm l/kmol-K273 200 -143690283.2041 200 -143590293.4082 200 -143540303.6122 200 -143530313.8163 200 -143570324.0204 200 -143670334.2245 200 -143830344.4286 200 -144070354.6327 200 -144400364.8367 200 -144590375.0408 200 -144290385.2449 200 -144190395.449 200 -144470405.6531 200 -146950415.8571 200 -157580426.0612 200 -153740436.2653 200 -149550446.4694 200 -145440456.6735 200 -141910466.8776 200 -139040477.0816 200 -136650487.2857 200 -134590497.4898 200 -132770507.6939 200 -131110517.898 200 -129590528.102 200 -128160538.3061 200 -126820548.5102 200 -125540558.7143 200 -124330568.9184 200 -123160579.1224 200 -122030

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589.3265 200 -120940599.5306 200 -119890609.7347 200 -118860619.9388 200 -117860630.1429 200 -116890640.3469 200 -115940650.551 200 -115010660.7551 200 -114100670.9592 200 -113210681.1633 200 -112330691.3673 200 -111470701.5714 200 -110630711.7755 200 -109790721.9796 200 -108970732.1837 200 -108170742.3878 200 -107370752.5918 200 -106590762.7959 200 -105820773 200 -105050

USING PENG ROBINSON:-

Temperature Pressure CpK Atm J/kmol-k

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273 200 10367.1695283.2041 200 9638.22249293.4082 200 8793.62355303.6122 200 7797.14008313.8163 200 6598.84867324.0204 200 5127.50255334.2245 200 3276.67578344.4286 200 878.353755354.6327 200 37300.233364.8367 200 37638.8278375.0408 200 23836.3054385.2449 200 14923.0692395.449 200 38670.8865405.6531 200 133146.43415.8571 200 148873.641426.0612 200 166624.5436.2653 200 175903.495446.4694 200 162496.609456.6735 200 137104.84466.8776 200 115609.182477.0816 200 100545.662487.2857 200 90151.89497.4898 200 82783.3317507.6939 200 77384.5371517.898 200 73309.776528.102 200 70157.032538.3061 200 67667.8539548.5102 200 65670.1643558.7143 200 64045.7697568.9184 200 62711.1016579.1224 200 61605.4934589.3265 200 60684.1044599.5306 200 59912.854609.7347 200 59265.6585619.9388 200 58722.0863630.1429 200 58265.8507640.3469 200 57883.9727650.551 200 57565.8596660.7551 200 57302.9286670.9592 200 57087.8946681.1633 200 56914.8123691.3673 200 56778.6157701.5714 200 56674.9924711.7755 200 56600.258721.9796 200 56551.3143732.1837 200 56525.3561742.3878 200 56520.0389752.5918 200 56533.2692762.7959 200 56563.2048773 200 56608.2129

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temperature Pressure CVK Atm j/kmol-k273 200 -3404300283.2041 200 -2883800293.4082 200 -2459500303.6122 200 -2112200313.8163 200 -1827700324.0204 200 -1594900334.2245 200 -1405900344.4286 200 -1255400354.6327 200 -1101500364.8367 200 -1020900375.0408 200 -204540385.2449 200 -416710395.449 200 -1215500405.6531 200 41824.81415.8571 200 41128.15426.0612 200 40280.77436.2653 200 39384.2446.4694 200 38706.11456.6735 200 38287.71466.8776 200 38040.44477.0816 200 37915.67487.2857 200 37878.78497.4898 200 37904.68507.6939 200 37976.21517.898 200 38081.77

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528.102 200 38213.36538.3061 200 38365.26548.5102 200 38533.39558.7143 200 38714.7568.9184 200 38906.85579.1224 200 39108.07589.3265 200 39316.94599.5306 200 39532.34609.7347 200 39753.36619.9388 200 39979.27630.1429 200 40209.44640.3469 200 40443.35650.551 200 40680.57660.7551 200 40920.7670.9592 200 41163.43681.1633 200 41408.45691.3673 200 41655.49701.5714 200 41904.31711.7755 200 42154.71721.9796 200 42406.47732.1837 200 42659.41742.3878 200 42913.36752.5918 200 43168.17762.7959 200 43423.65773 200 43679.67

CONCLUSIONS:-

By using the NRTL and Peng Robinson we concluded that There is a peak either upward or downward on the graphs drawn among any thermodynamic property and temperature from 400-450oC.

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EXPERIMENT NO : 3

OBJECTIVE:

TO STUDY AND SELECT DIFFERENT THERMODYNAMIC MODELS/ FLUID PACKAGES FOR THE GIVEN COMPONENTS/SPECIES IN THE SYSTEM.

THERMODYNAMICS MODELS:

Activity coefiicient modelsUNIFAC (LLE, VLE)UNIFAC (polymers)UNIQUAC,NRTLWILSONEquations ofstatePeng-RobinsonGrayson streed

PROCEDURE:

1) first of all I opened Aspen to open data browser option in the main menu and click on the component option then select the components.

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2) After choosing the components I opened properties specifications and select the required options e.g in base method option I select peng- robinson.

3) After closing the properties specifications, I opened tools option and then click on analysis and further on binary, then component analysis properties option opened. Chose the component from previously chosen components. I select Txy analysis type and Pxy analysis type, vapor- liquid phase and select base component then I press “GO”. In this panel we can select overall range, pressure units also.

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GRAPH:

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PROPERTIES:

I am able to plaot graph and after closed the graph screen, I also get a result of binary analysis.

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To found and checked whether I choose correct or wrong base method I draw the equilibrium curve for acetone-water mixture, so I got to PLOT WIZARD option, and click on equilibrium curve option and click on FINISHED.

FOR PXY:

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FOR TXY:

NTRL:

Again I opened properties specifications and select the required options’ this time I select NTRL. Model is also changed from component analysis properties from where we select analysis type…

I get a graph. to found and checked this time I choose or wrong base method I draw the equilibrium curve for Acetone-water mixture, so, I got to PLOT WIZARD option, and click on equilibrium curve option and click on FINISHED

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CONCLUSIONS:

1) I get the equilibrium curve for water- acetone mixture but this curve is not justify or matched with literature equilibrium.2) I concluded that I select a wrong base method, so I go for another base method from ideal system and checked it.3) By selecting NTRL and WILSON, I found the same and correct results because it matched with literature curve which is obtained by experimental data.4) NTRL gave correct results because it is for the REAL systems. For the calculation of activity coefficients in multi component systems different models (e.g. Wilson, NRTL) are available.5) NRTL and Wilson are applicable for Binary Systems, Multi component systems, Azeotropic Systems.

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EXPERIMENT # 4

OBJECTIVE:

TO DRAW A FLOWSHEET OF A CHEMICAL PROCESS PLANT ON THE WORKSHEET OF ASPEN PLUS 2006.5

THEORY:

FLOW SHEETA flowchart is a type of diagram that represents an algorithm or process, showing the steps as boxes of various kinds, and their order by connecting them with arrows. This diagrammatic representation illustrates a solution to a given problem. Process operations are represented in these boxes, and arrows; rather, they are implied by the sequencing of operations. Flowcharts are used in analyzing, designing, documenting or managing a process or program in various fields

PROCEDURE:

First of all we open the aspen plus software. Then for THF feed I use stream line 1 at condition of 250C and 1 atm, then I use

pump B2 to pressurized liquid to make its conversion easy. Then stream 2 from pump come in heat exchanger B3 which converts high

pressurized liquid in vapor at temperature 872c and at 1 atm. I select the second equipment that was a mixer B4, THF after passing through

heat exchanger sent to the mixer stream line 3 and another stream is come inside the mixer as a feed that is H2S stream line 16 at 25c and 1 atm .

Stream line 4 from mixer B4 come in pump then high pressurized liquid stream line 5 comes in reactor B5.

In reactor there is alumina act as a catalyst, the temperature of the product from reactor is very high so I pass it through the cooler B1 that results decrease in temperature.

Then stream line 6 enter in flash vessel B6.I use flash vessel because I have to separate vapor liquid mixture ,flash vessel will decrease the pressure and liquid will separate from vapor.

The flue gases stream line 54 are sent to the furnace B8 where it burns. Then I sent crude thiophane in a storage tankB9 by stream line 43, storage tank

required before every batch process to maintain flow rate. After that I set the valve B10 to control flow rate. Then I use washing tank B15 in which NaOH solution stream line 33 as washing

medium and crude THF stream line 13 are sent. Then I again sent washed solution to the storage tank B 17 by stream line 7. After that I sent that solution to the batch column B13. I use batch column

because I want to achieve maximum concentration of thiophane. And there is also a recycle stream, stream line 23 from the batch column to the

mixerB4 as I treated again the non reacted solution in the reactor B5. At last I store thiophane in a storage tank B14.

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To run this simulation on software one must have to provide required parameters of feed and other equipments.

Purpose of using flash vessel:The “flash”mean changing a liquid into vapour at low pressure. The flash vessel is used where we have to separate liquid and vapour from stream carrying the both phases.

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EXPERIMENT # 5

OBJECTIVE:

PERFORMANCE OF FLASH CALCULATION FOR FOLLOWING STREAM.

OPERATING CONDITIONS: Pressure=15 bar Temperature=25c Flowrate=100kmol/hr

PROCEDURE:

First of all I open aspen plus 2006.5 Then I draw a flow sheet as following

Component Composition (%)

Ethane 40

Propane 40

n-butane 20

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Then I gave title to my flow sheet

Then I select the component,their compositions, base method for calculations,

and at the last I selected temperature pressure as following Component selection

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Selection of base method

Temperatue unit selection

Temperature,pressure&composition selection

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Then I enter stream data of stream 1 as

Then I enter data of stream 2 as

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All my inputs are completed and then I go for simulation to run

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I also took other values like entropy,enthaply,material and energy balance

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EXPERIMENT # 06

OBJECTIVE:

To design the distillation column for the separation of iso-butane and normal butane from the mixture of given components

component Wt.fraction

n-butane 0.0978

Propane 0.0085

Iso-pentane 0.0104

Iso-butane 0.584

n-heptane 0.299

Also plot the equilibrium curve for isobutene &n butane. The temperature profile for distillation column

The composition of each stage of distillation column Relative volalities of component &k-value chart

Feed condition: Temperature:10 F Pressure: 101.325kpa

THEORY:

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DISTILLATION

A process in which a liquid or vapour mixture of two or more substances is separated into its component fractions of desired purity, by the application and removal of heat.Distillation is based on the fact that the vapour of a boiling mixture will be richer in the components that have lower boiling points.Therefore, when this vapour is cooled and condensed, the condensate will contain more volatile components. At the same time, the original mixture will contain more of the less volatile material.

FRACTIONAL DISTILLATIONS

Mixtures of liquids whose boiling points are similar (separated by less than 70°C) cannot be separated by a single simple distillation. In these situations, a fractional distillation is used.

VACUUM DISTILLATIONS

Vacuum distillation is distillation at a reduced pressure. Since the boiling

point of a compound is lower at a lower external pressure, the compound

will not have to be heated to as high a temperature in order for it to boil.

Vacuum distillation is used to distill compounds that have a high boiling

point or any compound which might undergo decomposition on heating at

atmospheric pressure. The vacuum is provided either by a water aspirator

or by a mechanical pump.

DISTILLATION AT TOTAL REFLUX

The total reflux condition represents operation with no product removal. All the overhead vapor is condensed and returned as reflux. Consequently, the reflux ratio (L/D) is infinite. This, in turn, makes the operating lines the 45 degree line .With the operating lines on the diagonal, they are as far as they can get from the equilibrium curve, so if the number of plates are stepped off using the diagonal and the equilibrium curve, the number of theoretical stages will be a minimum.Often, columns are operated at total reflux during their initial startup, and product is not withdrawn until a separation close to that desired is achieved.

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PROCEDURE:

1. First of all I open aspen plus 2006.5

2. Then I select the components from the component list.

3. After selection of the components, I enter the minimum and maximum temperatures of the process.

4. Then, I draw the flow sheet.

5. I enter the stream data of stream 1.

6. I assigned the name of stream 1 as feed.

7. Then entre the stream temp and pressure 10 F &101.325 KPa respectively.

8. Then I open the distillation column and select the condenser type as total.

9. Then I add the no. of stages.

10. Then add feed stage stream

Flow sheet

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Component selection

Specification of stream 1

Feed stage selection

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Specification of block 1

Simulation runs:

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Result of stream 1

Relative volatility graph

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k-value profile

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Vapour composition profile

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Temperature profile

CONCLUSION :

We are able to find the temperature and composition of the mixture at each stage with the help of graph

We could easily find out the feed stage at which maximum separation occur Its give accurate results and save our time.

At total reflux.

All condensate is returned to the column

It requires the least number of stages.

Practically no overhead product and no bottom product can be made and no feed is introduced.

It is possible to operate experimentally a fractionating column at total reflux when the system inventory is large and only very small samples of distillate and bottoms are removed

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EXPERIMENT # 07

OBJECTIVE:

Simulation of heat exchanger by using software aspen plus(2006.5)

THEORY:

HEAT EXCHANGER:

A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another (hot and cold fluid).

COMMON EXAMPLE

The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air.

THE TWO MAIN TYPES OF HEAT EXCHANGERS:

1. Parallel Flow Heat Exchanger

2. Counter Flow Heat Exchanger

PARALLEL FLOW HEAT EXCHANGER

In parallel flow heat exchangers, the two mediums enter the exchanger at the same end, and travel in parallel to one another to the other side.

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Temperature profile for parallel heat exchanger:

Counter Flow Heat Exchanger

In counter flow heat exchangers the fluids enter the exchanger from opposite ends. The counter flow design is most efficient, in that it can transfer the most heat from the heat transfer medium.

Temperature profile for counter flow heat exchanger:

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PROCEDURE:

First of all I open Aspen plus and select shell and tube heat exchanger and draw

flowsheet as follow

Then I select the symbols of feeds & products that show the ethylene glycol is inside the shell

and freon is in tubes.

After this we chose our required components E- Glycol & Freon and base method NRTL then we specify the inlet streams

Specifications of stream 1:

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Specifications of stream 2:

Then we open HeatX specifications panel and mention the required specifications. In specification panel we chose the detailed option and selected hot fluid in shell side.

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After clicking on next method HEATX Geometry opens. we select shell type F- two pass shell

And gives the inside shell diameter.

Then opens a tubes panel and select option bare tube and also gives the value of no. of tubes, length, pitch and chose our required pattern and material. In tube size we select

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actual option and gives the inner and outer diameter of tubes.

Next option is baffle. We chose rod type baffle, gives the no. of baffles, inner and outer diameter of ring and total length of support rods per baffle.

Then comes the nozzles option we give the shell side and tube side diameter value.

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After giving all the specifications we run our simulation successfully. Then open our results summary for checking our results. Heat duty is calculated by the software.

Results are balanced mass and mole flow of inlet and outlet streams are equal.

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Other variables are calculated by the software of input and output streams.

Pressure drop and velocities of our system is

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Overall stream results:

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CONCLUSION:

We are able to design heat exchanger Its give accurate results LMTD value comes out to be 114.06 F

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EXPERIMENT # 08

OBJECTIVE:

To design RCSTR on Aspen plus(2006.5)

GIVEN DATA:

Inside reactor:

Pressure= 15 atm temperature=430k vol. of reactor=100m3

Liquid phase reaction K=15280000kmols-1m3

Benzene=0.4kmol/s ethylene=0.2kmol/s

Reactions:

E + B= EB

EB +E =DEB

DEB + B=EB

Reaction kinetics:

k1=CECB(1.528*106)e(-71.13*10^6/RT)

k2=CECEB(2.778*104)e(88.68*10^6/RT)

k3=CDEBCB(0.4167)e(-62.76*10^6)

THEORY

CONTINUOUS-FLOW STIRRED-TANK REACTOR (CSTR)

In a continuous-flow stirred-tank reactor (CSTR), reactants and products are continuously added and withdrawn. In practice, mechanical or hydraulic agitation is required to achieve uniform composition and temperature, a choice strongly influenced by process considerations. The CSTR is the idealized opposite of the well-stirred batch and tubular plug-flow reactors. Analysis of selected combinations of these reactor types can

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be useful in quantitatively evaluating more complex gas-, liquid-, and solid-flow behaviors.

Continuous stirred tank reactors, (a) With agitator and internal heat

transfer surface, (b) With pump around mixing and external heat transfer

surface

Because the compositions of mixtures leaving a CSTR are those within the

reactor, the reaction driving forces, usually the reactant concentrations, are

necessarily low. Therefore, except for reaction orders zero- and negative, a

CSTR requires the largest volume of the reactor types to obtain desired

conversions. However, the low driving force makes possible better control

of rapid exothermic and endothermic reactions. When high conversions of

reactants are needed, several CSTRs in series can be used. Equally good

results can be obtained by dividing a single vessel into compartments

while minimizing back-mixing and short-circuiting. The larger the number

of CSTR stages, the closer the performance approaches that of a tubular

plug-flow reactor.

Continuous-flow stirred-tank reactors in series are simpler and easier to

design for isothermal operation than are tubular reactors. Reactions with

narrow operating temperature ranges or those requiring close control of

reactant concentrations for optimum selectivity benefit from series

arrangements. If severe heat-transfer requirements are imposed, heating or

cooling zones can be incorporated within or external to the CSTR. For

example, impellers or centrally mounted draft tubes circulate liquid

upward, then downward through vertical heat-exchanger tubes. In a

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similar fashion, reactor contents can be recycled through external heat

exchangers.

The CSTR configuration is widely used in industrial applications and in

wastewater treatment units (i.e. activated sludge reactors).

PROCEDURE

First of all I run the Aspen plus(2005.5) software and select component.

Then I choose the symbols of FEED, CSTR and PRODUCT. Then I specify the temperature, pressure, flow rate and necessary

conditions i.e.conversion, frequency factor and activation energy and intial feed temperature

After that I made a reaction between benzene and ethylene

Flow sheet:

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Component selection:

Base method selection :

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Specification of stream 1:

Specification of stream 2:

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Specification of block 1:

Reactions :

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Kinetics:

Inputs of R-1

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Required input complete:

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Stream custom results summary:

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Reactor results:

CONCLUSIONS:

In case of CSRTR aspen plus can help us in number of way like

Use when reaction kinetics are known and when the reactor content have same properties as outlet stream.

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Allow for any number of feed, which are mixed internally

Up to three products stream are allowed,vapour,liquid1,liquid 2,or vapour,liquid,free water

Will calculate duty at given temperature temperature at given duty

Can model equilibrium reaction simultaneously with rate basedreaction

BIBLIOGRAPHY

First reference.

Class Notes and Lectures

Additional references.