METHOD OF PREVENTING METAL DUSTING IN A GAS HEATED REFORMING APPARATUS
The specification describes a gas heated reformer apparatus comprising: one or more tubes containing a steam reforming catalyst; and a shell surrounding said tube(s) and together with the tube(s) defining a shell side; wherein the shell comprises an inlet and outlet for a heat exchange medium; wherein the shell side is provided with a water gas shift catalyst located at one or more areas of the shell side where during use the heat exchange medium in contact with the shell side has a temperature of 500-750° C. Also described is a plant for producing hydrogen, ammonia or methanol comprising the gas heated reformer. A water gas shift catalyst can be retrofitted to an existing gas heater reformer.
1 . A gas heated reformer apparatus comprising:
one or more tubes containing a steam reforming catalyst; and
a shell surrounding said tube(s) and together with the tube(s) defining a shell side;
wherein the shell comprises an inlet and outlet for a heat exchange medium;
wherein the shell side is provided with a water gas shift catalyst located at one or more areas of the shell side where during use the heat exchange medium in contact with the shell side has a temperature of 500-750° C.
2 . An apparatus according to claim 1 , wherein the water gas shift catalyst is only located at areas of the shell side where during use the heat exchange medium in contact with the shell side has a temperature of 500-750° C.
3 . An apparatus according to claim 1 , wherein the steam reforming catalyst is located within the tube side volume.
4 . An apparatus according to claim 3 , wherein the tube side volume includes one or more catalyst beds comprising a steam reforming catalyst.
5 . An apparatus according to claim 3 , wherein the tube side volume includes one or more structures coated with a steam reforming catalyst.
6 . An apparatus according to claim 1 , wherein the tube(s) are at least partially made of steel, a nickel-containing steel or a nickel-based alloy.
7 . An apparatus according to claim 1 , wherein the water gas shift catalyst is provided as a coating on the outer surface of the tube(s).
8 . A plant for the production of hydrogen, ammonia or methanol, comprising a gas heated reformer apparatus according to claim 1 .
9 . A plant according to claim 8 , comprising a gas heated reformer and autothermal reformer arranged in series, and arranged so that partially reformed gases from the autothermal reformer are fed to the shell-side of the gas heated reformer to provide heating for the reforming reactions taking place on the tube-side of the gas-heated reformer.
10 . A steam reforming process carried out in a heat exchange reformer apparatus according to claim 1 , comprising the steps of:
providing a heat exchange medium comprising a synthesis gas to the inlet of the shell side; and
carrying out water gas shift on the shell side.
11 . A process according to claim 10 , wherein the synthesis gas fed to the inlet of the shell side has a methane content of less than 10 vol %.
12 . A process according to claim 10 , wherein the synthesis gas fed to the inlet of the shell side has a methane content of less than 5 vol %.
13 . A process as claimed in claim 10 , wherein the temperature of the heat exchange medium fed to the inlet of the shell side is 700° C. or more.
14 . A process as claimed in claim 10 , wherein the pressure of the heat exchange medium fed to the inlet is 20-80 bar abs.
15 . A process as claimed in claim 10 , wherein the pressure of the heat exchange medium fed to the inlet is 20-55 bar abs.
16 . A method of retrofitting a gas-heated reformer apparatus, the apparatus comprising:
one or more tubes and a shell surrounding the tube(s) and together with the tube(s) defining a shell side, wherein the shell comprises an inlet and outlet for a heat exchange medium;
the method comprising the step of providing the shell side with a water gas shift catalyst located at one or more areas of the shell side where during use the heat exchange medium in contact with the shell side has a temperature of 500-750° C.
17 . A method according to claim 16 , wherein the step of applying a water gas shift catalyst to the shell side of the reformer involves applying a coating of water gas shift catalyst on one or more of the existing tubes.
18 . A method according to claim 17 , wherein the tubes are at least partially made of steel.
19 . A method according to claim 16 , wherein the step of applying a water gas shift catalyst to the shell side of the reformer involves replacing one or more of the tubes with a tube having a water gas shift catalyst applied on its outer surface.
20 . (canceled)