FIS-483 Engineering Study Report R1.03.11.19
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Marathon Petroleum Company, Catlettsburg Refinery, KY<br />
Capacity Improvement <strong>Study</strong> of LPCCR Platformer Heater (1-44-B-1/2/3/4)<br />
1.3 Operating Observations<br />
<strong>FIS</strong> has analyzed daily operating data of Platformer Heater for one year provided by<br />
Marathon. The following observations were made regarding the current operation of<br />
the heater:<br />
❖ Average feed flow rate to each cell is 263,190 lb/hr.<br />
❖ Average firing rate is 235.22 MMBtu/hr.<br />
❖ Feed inlet and outlet temperature in each cell are lower than the original design<br />
temperatures. Feed temperature rise in Charge Heater, inter heater 1 and Inter<br />
Heater 2 is higher than the design by 20°F.<br />
❖ Flue gas temperature leaving the convection section is around 571°F.<br />
❖ The excess O2 in the flue gas is in the range of 4.4%.<br />
❖ The burners are operated at higher fuel gas pressure in all the radiant cells than<br />
the original design. The average fuel gas pressure for No.1 Interheater, Charge<br />
heater, No.2 Interheater and No.3 Interheater are 22.2 psig, 25.1 psig, 22.4 psig<br />
and 28.5 psig respectively.<br />
❖ Firing rate (LHV) calculated from fuel pressure almost matches the firing rate<br />
provided by client<br />
❖ The calculated bridgewall temperature is higher than the actual. It could be that<br />
the radiant absorbed duty is higher than the calculated. Operating data<br />
simulation is indicating that the firing rates should be lower than the actual. It is<br />
also indicating that actual steam production is lower than calculated. We are not<br />
able to close the heat balance. This could be due to fuel gas flow measurement.<br />
1.4 Recommendation<br />
<strong>FIS</strong> recommends recovering process absorbed heat duty in convection section<br />
based on <strong>FIS</strong> Patented Split Flow Technology. We have optimized the required<br />
process absorbed duty as well as the design steam generation.<br />
In the proposed split flow arrangement, the process flow to the heater is split<br />
between radiant and convection sections. About 22.4-26.5% of the charge rate<br />
goes to the convection section split flow coil and the balance to the radiant coils.<br />
<strong>FIS</strong> proposes to run split flow piping from the inlet manifolds to the new convection<br />
coils and then return the convection section outlet split flow piping back to the<br />
outlet manifold from the radiant. We recommend installing a butterfly control valve<br />
to control the flow to the split flow convection coils so that the outlet temperature<br />
is maintained the same as the radiant section.<br />
The new convection section will be completely prefabricated in the shop. It<br />
consists 15 rows of tubes arranged in two modules. The bottom module consists<br />
of 7 rows of tubes and the top module consist of the rest 8 rows of tubes.<br />
Furnace Improvements<br />
Low Cost Solutions for Fired Heaters 12
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