Promax, MDEA

Tutorial Example of Using MDEA for H2S Removal in ProMax.168... 

TUTORIAL EXAMPLE OF USING MDEA FOR H2S REMOVAL IN PROMAX... 

Example ProMax simulations for H2S removal using the MDEA process. 

Finally, specify the makeup feed stream input to the second mixer to have a temperature of 35°C and pressure of 2 bar. To be an effective makeup stream, the flow rates of MDEA and H2O must equal the flow rates of those two components lost via the CO2 product and clean syngas streams. Although trivial to compute at the moment, once the recycle loop is closed, this number must be computed for each flow sheet convergence iteration in order to be able to physically achieve a steady state and prevent eventual dry-up of the solvent. Unlike ProMax, which has a Make-up/Blow-down block to handle this specific scenario. Aspen Plus has more generic tools that can be used instead. For example, a calculator block can be added that computes and sets the inlet composition and flow rate of the makeup feed stream for every flowsheet iteration. To do this, first configure the makeup stream to have a mole flow of H2O and MDEA of 1 kmol/h each. These are strictly dummy variables. However, it is critical that the Total Flow Rate is left blank. By specifying it in this manner, we are creating a specification in which the calculator block will be able to directly overwrite the dummy numbers of 1 kmol/h with its own calculations just before the second Mixer block executes. 

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