Producción de etilenglicol en hysys

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Ethylene Glycol Plant

Workshop
Ethylene glycol has many industrial uses: a feed stock for polyester resins, a hydrate inhibitor in natural gas pipelines, an all-weather antifreeze and coolant, or an industrial solvent. Ethylene oxide and water are fed to a reactor to produce ethylene glycol. The product stream is fed to a distillation column where the excess water and ethylene oxide arestripped off the top and the ethylene glycol is the bottom product.

Learning Objectives
After completing this module, you will be able to:

• • • •

Simulate CSTR reactors Simulate an Ethylene glycol plant Use the recycle operation in HYSYS Choose suitable locations for recycles

Prerequisites
Before beginning this module, you need to be able to:

• Add and define the simulationbasis, including components, property packages, and reactions. • Add streams and operations to a simulation.

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Process Overview

Column Overview

Ethylene Glycol Plant

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Building the Simulation
Defining the Simulation Basis
Start a New case and choose the NRTL Activity Model. The components are Ethylene Oxide (C2H4O), Water (H2O) and Ethylene Glycol (C2H6O2).
Fast track to page11.

These components can be hard to find in the long list of available components in HYSYS. Use the Formula filter and type the chemical formulas given above into the Match Cell. This will help you find the desired components quickly and easily. Go to the Binary Coeffs tab. Select UNIFAC VLE as the Coeff Estimation method to estimate the missing binary coefficients and press Unknowns Only. Thiswill estimate the coefficients for the ethylene oxide / ethylene glycol pair.

Adding the Reactions
On the Rxns tab, add the following reaction to the Fluid Package: C2H4O + H2O → C2H6O2 1. 2. To define the reaction, press the Simulation Basis Mgr button and select the Reactions tab. Add all of the Fluid Package components by selecting the Add Comps button and pressing the Add this Group ofComponents button in the window that appears. Press the Add Rxn button, choose Kinetic, and press the Add Reaction button.

3.

In the Stoichiometry and Rate Info group, define the reaction stoichiometry of the reaction previously stated (-1 for reactants, and 1 for product comps).

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Ethylene Glycol Plant

4.

Complete the Basis and Parameters pages as below: Enter...

In ThisCell...
Basis Basis Base Component Rxn Phase Basis Units Rate Units Parameters Forward Reaction A E

Molar Concn C2Oxide Combined Liquid kgmole/m3 kgmole/m3-s

5.0e+06 5.0e+04

No reverse reaction is defined in this example. 5. Return to the Simulation Basis Manager by closing the Kinetic Reaction window. Return to the Rxns tab of the Fluid Package. Press the Add Set button to add the GlobalRxn Set to the Current Reaction Sets group. Close the Fluid Package view. Press the Enter Simulation Environment button.

6.

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Ethylene Glycol Plant

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Adding the Feed streams
Add two feed streams with the following information. All compositions are entered as mole fractions In This Cell...
Conditions Name Temperature Pressure Molar Flow Composition C2Oxide H2O EGlycol 1.0 0.0 0.0EOx Feed 25°C (77°F) 120 kPa (17.4 psia) 105 kgmole/h (230 lbmole/hr)

Enter...

Conditions Name Temperature Pressure Molar Flow Composition C2Oxide H2O EGlycol 0.0 1.0 0.0 Water Feed 25°C (77°F) 120 kPa (17.4 psia) 150 kgmole/h (330 lbmole/hr)

Save your case!

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Ethylene Glycol Plant

Adding the Unit Operations
CSTR Reactor
Add a CSTR operation and enter the followinginformation. Be sure to assign the Global Rxn Set as the Reaction Set for the separator to model the reactor. In This Cell...
Connections Name Inlets Reactor EOx Feed Water Feed Vapour Outlet Liquid Outlet Energy Parameters Pressure Drop Volume 10 kPa (1.5 psi) 2 m3 (71 ft3) Rx Vapour Rx Liquid Rx Coolant

CSTR button

Enter...

1. 2.

On the Reactions tab, select the Global Rxn Set and Rxn-1...