HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
(OP)
Dear all,
I am trying to find the best way to simulate and design a distillation column with a defined cuts for a sidedraw. The sidedraw will be the mainproduct in this operation.
Example:
Assay Boilingrange: 150°C to 350°C
Sidedraw with CUT: 200-300°C
Which type of Subflowsheet and respective specifications should be used for the simulation?
I solved the Simulation using: “distillation column subflowsheet” with the specs: "temperature on the draw tray" to 200°C @ vap frac 1 and 300°C @ vap frac 0.
But…this way seems to be too time consuming and I think there might be an easier way as defined cuts for sidedraws should be used often enough in refinery-engineering.
What's your poinion?
Regards
Andre
I am trying to find the best way to simulate and design a distillation column with a defined cuts for a sidedraw. The sidedraw will be the mainproduct in this operation.
Example:
Assay Boilingrange: 150°C to 350°C
Sidedraw with CUT: 200-300°C
Which type of Subflowsheet and respective specifications should be used for the simulation?
I solved the Simulation using: “distillation column subflowsheet” with the specs: "temperature on the draw tray" to 200°C @ vap frac 1 and 300°C @ vap frac 0.
But…this way seems to be too time consuming and I think there might be an easier way as defined cuts for sidedraws should be used often enough in refinery-engineering.
What's your poinion?
Regards
Andre





RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
The same specification variable should be available on the simulator you are using ?
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
I defined two Specs (in HYSYS called 'cutpoint') to receive a defined draw:
Spec1:
Stage 13
Type: D86
Temp: 200°C
Phase: Liq
Spec2:
Stage 13
Type: D86
Temp: 300°C
Phase: Vap
Let's say stage 13 ist my stage for the sidedraw.
For solving the simulation, I have to vary the drawstage and the cutpoint-specs manually - this way seems to be quite time-consuming.
Regards,
Andre
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
How many specs do you have to provide and what are you providing in addition to these two?
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
see my specs in the attached pdf.
@TD2K:
Wny are you specifying both the vapor and liquid D86 points --> warong post by myself...see pdf attached
My question: is there an easier way to run the simulation than using these three specs?
Regards,
Andre
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw
In general terms, I prefer to initially set up a distillation just on flows, that gets the model converged usually fairly easily. I can then look at the streams and either start changing the flows to get properties to match what I want or change the spec then to a D86 or some other specification. Do one stream at a time, don't try to put D86 specs on all three streams and hit the "solve" button.
Initial estimates can really help. Spend some time with pen and a piece of paper so you have an idea of what the general splits should be. If you are setting up a crude tower, you should be able to look at the feed stream and get reasonable estimates for the naphtha, kero, diesel, etc streams from the feed assay.
RE: HYSYS – Simulation of a distillation column with defined cutpoints for sidedraw