5 replies to this topic

[Brunorfa]

Hi Everybody!! I have a trouble trying to simulate a biodiesel industry. I'm stocked at the flash tank!

 

In the flash, i have the following composition: Methanol 5,1605%

                                                                       Glycerol   0,4544%

                                                                       Triolein    0,3171%

                                                                       M-Oleate 94,0681%

 

The inlet flow is about 3kgf/cm² of pressure.

The vacuum in the FLASH TANK is about -570 mmHg.

 

But when I try to simulate, the vapor flow that I get is: Methanol 99,9780%

                                                                                    Glycerol  0,0193%

                                                                                    Triolein   0,0001%

                                                                                   M-Oleate 0,0026%

 

This result is close to real, but the mass flow is 0kg/h what is not true.

 

If someone can help me, I'd be gratefull!

[Pilesar]

The amount of flashed vapor in your simulation depends on temperature, pressure, composition, thermodynamics package, and a properly coded simulation flash algorithm. If this is a theoretical exercise and you are trying to drive more methanol overhead, then I suggest you add heat to your feed.

[Brunorfa]

Actually, this is a simulation of a real process. But I'm not getting good results. I'll try to use another fluid package cause in the real situation, at this pressure and temperature we get a really good separation!!

 

Do u have any other tip??

 

tks in advance

[Pilesar]

   Check the sensitivity of your simulation results to your inputs. Will reducing the flash pressure slightly give you the results you expect? Then perhaps your field pressure measurement does not adequately represent actual conditions or the simulated vapor pressures for one or more of your components is inaccurate.

   When simulating a process, keep the reason for the model in mind -- sometimes you can artificially adjust the model input data with no consequence to the intended engineering purpose.

[MrShorty]

A vapor flow rate of exactly 0 kg/hr suggests to me that your simulator believes that your specified flash condition is below the bubble point temperature of the feed or above the bubble point pressure. You have not given enough information for us to look at it for you, but my first response to a problem like this would be to look at the bubble point curve. Determine which side of the calculated bubble point curve you are on. Once you know where you are in relation to the bubble point curve, then you can better determine if, as Pilesar suggests, you simply need to make a small change in the input parameters, or if you need to rethink the entire process/calculation scheme.

[ENGR. JAWAD AHMED]

I HAVE COMPLETED MY POSTGRADUATE DIPLOMA AND NOW WANT TO DO RESEARCH OF M.E I NEED UR PRECIOUS SUGESSTION AS WELL HELP REGARDING MY RESEARCH TOPIC  I HAVE SELECTED "Process Simulation and Economic Analysis of Biodiesel Production Processes Using BIODIESEL (JETROPHA, PALM OIL, CASTOR, RAPESEED ETC....) VS BIODIESEL"  BUT IF ANY OTHER KIND OF TOPIC U HAVE THAT CAN EASILY DONE ON HYSYS SOFTWARE .... PLZ SUGGEST AND I NEED A BIODIESEL SIMULATIONS PRODUCED BY ANY VEGETABLE OIL KINDLY INBOX ME ..... I SHALL VERY THANKFUL TO YOU.

 

 

 

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