Objective
The efficiency of a primary reformer furnace/gas turbine combination will be improved by extensive preheating of the mixed feed going to the furnace and by installation of a highly efficient gas turbine of which the operating conditions can be adapted to suit the oxygen requirements of the furnace.
The extensive preheating of the mixed feed reduces the heat duty which has to be transferred in the radiant section considerably.
The installation of a highly efficient two shaft gas turbine improves the furnace efficiency by reducing the exhaust flow through the fire box down to the minimum amount required to achieve complete combustion of the furnace fuel.
Those effects, combined with the high efficiency of the gas turbine will result in savings of 75 million m3 of natural gas per year.
From those 75 million m3, 22 million are related to the improved gas turbine operation (better efficiency and less oxygen surplus).
The remainder, 53 million m3 of natural gas is due to the extended mixed feed preheat.
Steam reforming of hydrocarbon feeds is the principal process for the production of hydrogen gas and hydrogen containing gas mixtures. The desulphurized feedstock is diluted with large quantities of steam, then preheated to elevated temperatures and finally contacted with nickel catalyst.
Since several decades, this process takes place inside catalyst filled tubes, which are suspended in the radiant section of a furnace.
Unfortunately, only 30-35% of the heat released by the burners is effectively absorbed by the reformer tubes. The balance of the heat carried by the flue gases that leave the radiant section is recovered in various convection coils.The heat requirements of the radiant section determine the total fuel gas consumption of the furnace, as this heat needed at the highest temperature level.
To reduce the fuel gas consumption, it is intended to decrease the duty of the radiant section by extended preheating of the hydrocarbon/steam mixture before it reaches the catalyst tubes. This is done by installing a new highly alloyed mixed feed preheat coil in the convection section of the furnace. In this way, radiant heat is substituted by heat available in the convection section at a sufficiently high temperature level.
A second key factor in achieving the fuel gas savings is the installation of a second generation gas turbine. The amount of oxygen available in the exhaust gases from this machine matches closely the oxygen requirements of the primary reformer furnace.
In this way, the flow through the radiant box of the furnace is minimized allowing to reach the high temperatures required in the fire box with a lower fuel gas consumption.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
4541 HJ SLUISKIL (ZEELAND)
Netherlands