Cansolv CO
CO
SMR Large reference, but requires post-combustion CO capture for >90% capture
Flue gas
CO
Steam
CH
Feed gas pretreatment
CO capture
SMR
H
CO shift
Puri cation
(Option)
CO
Steam
ATR Feed pretreatment Steam for reaction Fired heater
CH
Feed gas pretreatment
CO capture
ATR
H
CO shift
Puri cation
O
CO emissions
Fired heater
Air Power
ASU
CO
HP steam
SGP No or minimal feed pretreatment Steam production using waste heat No direct CO emission from process
CH re nery fuel gas
CO capture
SGP
H
CO shift
Puri cation
O
Air Power
ASU
Figure 3 Comparison of different blue hydrogen technologies
may already have the advantage. Where this is not the case, blue hydrogen has a vital role to play in the energy transition. Essentially, while green hydrogen may be the better economic option in some locations, blue has an advantage in others and therefore both are needed in the short and medium term. Which type of blue hydrogen technology? Blue hydrogen can be produced in different ways, according to the technology used. Until recently, project developers usually had the choice of two established blue hydrogen technologies: SMR or autothermal reforming (ATR). Now, there is a third option; one with the potential to provide superior cost and CO₂- capture performance. The Shell Blue Hydrogen Process (SBHP) is a new way to produce blue hydrogen from natural gas, or other hydrocarbon gases (refinery off-gases), by integrating proven technologies that can be deployed rapidly (see Figure 2 ). The process is an oxygen- based, non-catalytic system, whereby Shell’s proven Shell Gas POx technology is utilised to manufacture syngas. After the water-gas shift reaction, CO₂ is removed with Shell ADIP ULTRA technology to leave a hydrogen stream for further purification. Shell Gas POx utilises
Shell’s proven Shell Gasification Process (SGP) technology, based on gas partial oxidation, which is a mature, cost-efficient, and de-risked technology with a 70-year track record. Established, de-risked technology The SBHP development journey is interlinked with the Shell Pernis refinery’s decarbonisation journey. In 1998, SGP technology was at the heart of Shell Pernis refinery’s residue upgrading. With no sequestration available, some CO₂ was vented to atmosphere, but Shell also found uses for it, routing up to 1 mtpa to greenhouses to accelerate crop growth. Further development took place when the Pearl GTL (gas-to-liquids) plant in Qatar came on stream in 2011, with some 18 SGP trains, each of which was able to convert natural gas into syngas with an equivalent pure hydrogen production capacity of 500 t/d. While green hydrogen may be the better economic option in some locations, blue has an advantage in others, so both are needed in the short and medium term
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