Design Project for Petroleum Engineers (HYSYS)

Design Project for Petroleum Engineers (HYSYS Homework Help)

Task 1
A stream containing the following in mole fractions: 0.1 C1; 0.04 C2; 0.03 n-C3; 0.02 n-C4; 0.21 H2O; 0.2 n-C6; 0.2 n-C7 and 0.2 n-C8. The stream temperature is 25 C and pressure is 2000 kPa. Its flowrate is 360,000 kg/hr.

a. Look at your feed steam, investigate its properties: i. Density ii. Viscosity iii. Heat capacity iv. Surface tension coefficient v. RVP

b. Put this stream into a three-phase separator (All equipment especially heat exchangers and columns, except tanks and separators MUST have a pressure drop across them).

c. Drop the pressure of the oil stream to 1400 kPa using a valve.

d. Put this oil stream through a two-phase separator

e. Take the oil stream and increase its temperature to 40 C using a heater. ( Acceptable pressure drops through heat exchangers is 1030 kPa – in this case use 10 kPa).

f. Put the heated oil stream into a two-phase separator.

g. Check the RVP of all three oil streams. Discuss.

h. Combine the gas/vapour streams from the two two-phase separators and increase the pressure of the combined stream to 1600 kPa. i. Combine all gas streams. j. Raise the temperature of the gas stream to 40 C using a heat exchanger and the oil stream as the heating stream. Use 10 kPa as pressure drop on tube- and shell-sides. k. Is the HE converged (yellow line means it is not converged)?

l. Try 38 C as the temperature of the gas stream. Discuss. 

Task 2 Solution:

This is your project work. Each student must input his/her own data. We have done a couple of examples input data in class. If you have not done that yet, pkease ask.

Key points: Parts f and g: Crude oil is stabilised if RVP is less or equal to 30 kPa. Keep RVP as close as possible to 30 kPa. Part J: there is some H2O in your gas stream. Must take it out before running it through the gas plant using an absorber. If you have liquid as a result of increasing the pressure, remove using a 2-phase separator. Parts k and l: Cooling is limited because of the ;arge difference in the flowrates of the two streams going through the exchanger. Heat integration means to reduce the duties of all heaters (cost of steam) and coolers (costs of coolants – Freon, liquid propane, etc.) by using available heating (high T streams) or cooling (low temperature) power in product streams BEFORE the heaters and coolers respectively.


Starting with the data sheet of your project, use HYSYS to do the following:

a. Components list: First choose your components (light hydrocarbons, acid gases and H2O – solvents later on). - Convert Saybolt Universal units (sec) to centipoise (cP) using google b. Fluid Package: Choose a fluid package c. Oil Manager: Enter the data, bulk properties (density and viscosity values); distillation (atmospheric TBP data) and light ends (composition of C1-C4, H2S and CO2). - Remember how to calculate the mass% of C1, C2, etc. - Total wt% given does not include H2S. Include H2S and value obtained will be slightly more than given one. That is OK. - Once you enter all data move from input assay to output blend, cut the oil by specifying number of cuts (hypothetical components) wanted. - Last step is to install the oil. Make sure you give the stream a name. d. Now ready to go to Simulation Window. - Enter T, P and flowrate (mass flowrate) – These should be ready from first report. - Go to composition; make sure you have oil in your stream (all the components with NBPs etc.) - Enter the composition of water – Normalise compositions will change - Re-enter light ends and water compositions, normalise 2-3 times till change is very little. e. Install a 3-phase separator - Check RVP of oil stream - Check if any H2O in gas stream f. Do you need a two-phase separator? If yes, heat the stream by 10 C in a heater; drop the pressure by 50 kPa before feeding it to the flash drum. - Check RVP again g. Do you need a second 2-phase separator? Repeat (f) if yes. h. Gather all gas streams in one header (stream) - Check composition - How much water you have in it? i. Increase the pressure of the combined gas stream by 1000 kPa. j. Check composition- Comments? k. Use a heat exchanger to cool oil stream. How much you can cool it by? Why so little? l. Looking at your process flow diagram carefully- How can you reduce your energy consumption? Explain and implement in HYSYS.