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[marco144]

i have read the article "ammonia next step" uploaded in this site and have some interesting idea on how to improve the process.
Im working operatively in the industry so i understand the notes of the author regarding the resistence too often that industry have to accept modifcation to existing idea.
Anyway im not sure to have fully understood what have been called the Isobaric Manufacturing ie:

"C. Isobaric Manufacturing.
The primary hurdle in the isobaric method of manufacturing ammonia is the poor conversion of methane at elevated pressure. The bottleneck is the maximum permissible temperature range due to metallurgical constraints in the reformer tubes. Synthesis pressures are no longer an issue with the development of the Kellogg Advanced Ammonia Process (KAAP), which utilizes a ruthenium-based catalyst operating at 90-100 ata (1470 psia). Thus, if the methane conversion can be increased by hydrogen separation, the process can be operated at higher isobaric pressures.
The synthesis compressor can be reduced to one small compressor at the natural gas feed. The power consumption in this compressor will be 3.0 MW for an isobaric pressure of 100 ata in the front end because of reduced gas flow and reduced differential pressure. The gas flow in synthesis compressor remains near 200,000 Nm3/h (117,715 scfm) while the flow will be reduced to near 45,000 Nm3/h (26,485 scfm) in natural gas compressor. The differential pressure in the synthesis compressor is 175 kg/cm2a (from 25 kg/cm2g to 200 kg/cm2g), while the differential pressure is only 60 kg/cm2a in natural gas compressor (from 40 kg/cm2g to 100 kg/cm2g). The power consumption is around 3.0 MW in the conventional recirculator. This will result
in a total power consumption of 6.0 MW in raising the pressure of synthesis gas. Presently, the power consumption in the synthesis gas compressor is around 25.0 MW for a conventional ammonia plant at same load. This ,however, requires the process air compressor to be operated at a discharge pressure of 100 ata (1470 psia) compared with a pressure of 34-35 ata (510 psia) in the conventional plant. The net energy saving in the isobaric process can be near 0.5 Gcal/tonne (1.98 MBtu/tonne). Moreover, it will also save the energy in CO2 compressor of the urea plant because the CO2 from the ammonia plant will be available at a much higher pressure."

Apart the above estimation on the absorbed power on which im not fully agreed, i understand that this means to have the front end pressure in the primary reformer at 100 bar (instead of the typical 30-40). Is this correct ?
if yes, which is the primarry reformer cost impact ?
are reformer at this pressure level already in commercial operation somewhere?

Thanks in advance