13 replies to this topic

[mehul]

I have notice during simulation of Pyrolysis Furnace in Petrosim and VMG sim with increasing of bulk residence time , yield of Ethylene increase is it possible?

[Bobby Strain]

No.

[mehul]

Thanks for Replying , then what is the problems with the modeling.?? 

[Bobby Strain]

For models that are even close to reality you must pay a hefty price. Like TechnipFMC's Spiro.

 

Bobby

[mehul]

I Have Checked in Spyro same things Happened.

Residence time 0.287969

Summary wt% 

H2 0.943047

CH4 15.785

C2H2 0.32585

C2H4 27.786

C2H6 3.727

MAC 0.331634

PPD 0.221013

C3H6 13.879

Residence time s 0.255565

H2 0.926958

CH4 15.345

C2H2 0.324114

C2H4 27.6

C2H6 3.703

MAC 0.335917

PPD 0.223868

C3H6 14.315

[Bobby Strain]

You appear to be modelling an old furnace. And without further information, I agree with the results you present. This is very low severity operation, and not a modern furnace. Typical ethylene yield from naphtha is above 35 wt%.

[mehul]

Thanks For Your Response , Yes I further check my model and reconfigure its Radiant tube geometry and now it is exactly match i.e if i reduced residence time , mass % of ethylene Yield Increased

 

Residence time   0.3347                  0.3745

Property Mass Flows Mass Flows

Unit                   tonne/hr                    tonne/hr

Hydrogen 0.126494216        0.124871432

Nitrogen 0                    0

CO                                  0                    0

Oxygen          0                    0

Methane              2.339436892          2.264064622                                 P/E                     P/E

Ethylene              4.433405143          4.306722525                           0.490548091    0.528358875

Ethane                 0.553673784          0.559572123

CO2                              0                           0

H2S                               0                           0

Propene                 2.174798431 2.275495069

Propane                 0.04841153           0.051967224

i-Butane 0.008699009 0.009955046

i-Butene 0.273057638     0.291197418

1-Butene 0.14084377 0.152214155

13-Butadiene 0.550685279 0.552482937

n-Butane 0.011446496 0.013477239

tr2-Butene 0.060344688 0.064331101

Edited by mehul, 21 October 2018 - 12:09 PM.

[KHANFA]

Hi All,

need help to calculate the ultimate yield of ethylene without using Spyro or Coilsim?

 

Any help will be must appreciated.

[Pilesar]

See if you can find yield curves in the manuals from the furnace manufacturer. You might can interpolate gas cracking curves with good results. Naphtha cracking predictions will be difficult to get accurately.

[shvet1]

Is it a new installation or existing one? Pilot testing is implementing for such issues. You should contact a proven R&D center.

[KHANFA]

Is it a new installation or existing one? Pilot testing is implementing for such issues. You should contact a proven R&D center.

its a existing ethylene cracker, can share some literature if possible 

[KHANFA]

See if you can find yield curves in the manuals from the furnace manufacturer. You might can interpolate gas cracking curves with good results. Naphtha cracking predictions will be difficult to get accurately.

i was able to find the curves but they are qualitative & does not shows the COT correlation with conversion in wt% or mol%. 

[shvet1]

 

Is it a new installation or existing one? Pilot testing is implementing for such issues. You should contact a proven R&D center.

its a existing ethylene cracker, can share some literature if possible 

 

 

There was a pilot unit to test the feed of steam cracker at a process plant I had been working on. The same for other similar process units, e.g. propylene ammoxidation to acrylonitrile. There was a local R&D center for such issues.

 

For info - Any modern high capacity process other than very well known like crude oil distillation is science-intensive and require R&D some degree of before industrial implementation is applied. Otherwise a minor change/deviation from planned consumption/yield/quality entails a huge loss of operating profit. A couple days in successful operation of a steam cracker will bring more money than any R&D center is able to spend during a couple of years.

 

As per industry practice it is cheaper to conduct experiments/studies in lab scale than in industry one.

Edited by shvet1, 30 August 2023 - 07:28 AM.

[KHANFA]

 

 

Is it a new installation or existing one? Pilot testing is implementing for such issues. You should contact a proven R&D center.

its a existing ethylene cracker, can share some literature if possible 

 

 

There was a pilot unit to test the feed of steam cracker at a process plant I had been working on. The same for other similar process units, e.g. propylene ammoxidation to acrylonitrile. There was a local R&D center for such issues.

 

For info - Any modern high capacity process other than very well known like crude oil distillation is science-intensive and require R&D some degree of before industrial implementation is applied. Otherwise a minor change/deviation from planned consumption/yield/quality entails a huge loss of operating profit. A couple days in successful operation of a steam cracker will bring more money than any R&D center is able to spend during a couple of years.

 

As per industry practice it is cheaper to conduct experiments/studies in lab scale than in industry one.

 

Thanks for your feedback.