7 replies to this topic

[yeek]

Working with a current Sulfur Recovery Unit currently and I wish to check the integrity of a particular heat exchanger with HTRI.

But before that I want to simulate the heating process in HYSYS so that I can get the physical properties of the shell fluid.

The problem is, the current stream has many different Sulfur Vapor (S2, S6, S8, etc). HYSYS has only one type of sulfur vapor component. I've thought of creating hypotheticals but I can't really find the physical properties of the S2, S6, S8 vapors.

Is this significant at all? Or should I not waste my time and just make some assumptions.

[Padmakar Katre]

Working with a current Sulfur Recovery Unit currently and I wish to check the integrity of a particular heat exchanger with HTRI.

But before that I want to simulate the heating process in HYSYS so that I can get the physical properties of the shell fluid.

The problem is, the current stream has many different Sulfur Vapor (S2, S6, S8, etc). HYSYS has only one type of sulfur vapor component. I've thought of creating hypotheticals but I can't really find the physical properties of the S2, S6, S8 vapors.

Is this significant at all? Or should I not waste my time and just make some assumptions.

Hi Yeek,
Sulphur Recovery Unit, reaction section cannot be simulated with Hysys. Creating these sulphur vapor components as Hypo-components will not yield the real/actual physical properties which you are going to use for design/rating of heat exchanger.

[yeek]

Working with a current Sulfur Recovery Unit currently and I wish to check the integrity of a particular heat exchanger with HTRI.

But before that I want to simulate the heating process in HYSYS so that I can get the physical properties of the shell fluid.

The problem is, the current stream has many different Sulfur Vapor (S2, S6, S8, etc). HYSYS has only one type of sulfur vapor component. I've thought of creating hypotheticals but I can't really find the physical properties of the S2, S6, S8 vapors.

Is this significant at all? Or should I not waste my time and just make some assumptions.

Hi Yeek,
Sulphur Recovery Unit, reaction section cannot be simulated with Hysys. Creating these sulphur vapor components as Hypo-components will not yield the real/actual physical properties which you are going to use for design/rating of heat exchanger.

Hi,

Thanks for your reply. I am not simulating the reaction section but upstream of the reaction of it. There is some heating of the Process Gas Stream that goes into the Claus reactor.

These heat exchangers are new and have to be rated with HTRI. But to use HTRI, I need the physical properties of the shell side fluid. The tube side fluid is HP steam which will condense.

I have the PFD of the whole process so I know what are the components in the Process Gas Stream so I intend to use these flow rates of the components from the PFD to be used in HYSYS. That way I can get the physical properties (viscosity, Heat capacity, etc) to be used in HTRI.

Am I wasting my time trying to simulate the S6, S8 vapors?

Regards.

[Dacs]

Hysys is somehow lacking in simulating Claus units and creating a hypothetical component for this purpose would also call for knowing much more than physical properties.

And if you're thinking of making an assumption to lump all S components into one (that is present in Hysys), it won't give you an accurate heat curve for your HTRI validation.

I suggest using another simulator (such as ProMax) will will give better results for this kind of system.

[Technical Bard]

It is possible to model this in HYSYS, but you must build complete hypothetical components, complete with vapour pressure, gibbs excess energy and other data. If you have access to the TRC thermochemical tables (or other similar sources) you can fit all the data and generate reasonable hypos.


However, I agree with Dacs that using something like Sulsim or ProMax is much simpler and less likely to result in errors.

[PaoloPemi]

if you presume there is change in components (chemical equilibria) you need a suitable solver, also it could be difficult to model phase equilibria for that process, in the case you have a single phase (for example vapor) then you can define one or more components with the average properties of that mixture and get reasonably results.

[hshethna]

If you look at V7.3 HYSYS, there is an example of a Claus plant simulation available. This will also show you how to model sulfur vapors with S, S2, S4, S6 and S8.

[Dacs]

If you look at V7.3 HYSYS, there is an example of a Claus plant simulation available. This will also show you how to model sulfur vapors with S, S2, S4, S6 and S8.

I do have that version at my disposal. I'll check and confirm it later.

Most probably the OP has already long moved on to other problems, but I'd like to share something worth sharing.

I was tasked to review the specifications of a certain liquid sulfur cooler (no condensation, only sensible heat change for the sulfur stream) and I wasn't able to come into terms with the results being given by Hysys (among other things, heat duties won't match) compared with the data at hand, presumably sourced from the designer's proprietary simulation (said designer specializes on sulfur degassing system), no matter how hard I tried tinkering with Hysys.

Since I don't have any other simulation software at hand, we were compelled to accept the vendor's design (guaranteed by them, which is a good thing for us). But for the benefit of doing verification, Hysys clearly shows its (lack of) capacity to simulate sulfur system, well with v7.2 at least.