Decarbonisation Technology - August 2023 Issue

H 2

CO 2

Carbon impact 1

CO 2

Capex 2

Lead time

Down time

Opex 2,3

production

recovery

[gCO 2 eq/MJH 2 ]

KgCO 2 /kgH 2

Nm³/h

Months

80,000

<12.5

0.28

Table 4 Option 3: BlueSMRp new parallel hydrogen unit with pre-combustion – carbon capture efficiency and investment metrics

H 2

CO 2

Carbon impact 1

CO 2

Capex 2

Lead time

Down time

Opex 2,3

production

recovery

[gCO 2 eq/MJH 2 ]

KgCO 2 /kgH 2

Nm³/h

Months

80,000

<11

0.09

Table 5 Option 4: BlueSMRe Renewable electric power to decrease fuel firing in the parallel hydrogen unit – reducing carbon emissions and investment metrics

The main aim of this solution is to provide users with a plug-and-play solution similar to the installation of the post-combustion carbon capture described in the reference case. For this BlueSMRp, there is no need for major changes to the existing hydrogen unit, and the resulting residual CO₂ emissions are even lower than in the reference case. Capital expenditure as well as operational expenditure are also reduced (see Table 4 ). Option 4: BlueSMRe In this case, the ‘e’ stands for ‘electric’. This solution (see Figure 5 ) is similar in concept to the one proposed for the BlueSMRp, However, it is based on integrating a renewable electric power import to decrease the fuel fired in the hydrogen production unit and therefore reduce CO₂ production. The obvious result is that this solution brings very low residual carbon emission, much lower than any of the other cases analysed. However, the downside is a higher operational expenditure mainly related to the cost of imported renewable electric power (see Table 5 ). Conclusion In conclusion, decarbonising existing SMR- based hydrogen production units is possible, and several solutions are viable. Each solution brings advantages and disadvantages related to the modifications required to be implemented, and all bring significant reductions in CO₂ emissions. It is possible to reduce the carbon intensity of the existing hydrogen production

Clean ue gas to atmosphere

Hydrogen product

Steam reforming

Shift

PSA

Feed

Renewable electric power (approx. 17MW)

PSA tail gas

BlueSMR E

CO for use or sequestration

unit from the initial value of 9.1 kg CO₂ per kg of H₂ produced down to less than 1 kg CO₂ per kg of H₂ produced, and even below 0.1 kg CO₂ per kg H₂ produced if the unit can be integrated with renewable electric power. Notes: Tables 1-5 1 According to UK regulation. 99% availability, grid connected power. 2 Compared to the reference case (post-combustion capture). 3 Prices: Natural gas 5 USD/MMBtu; Steam: 14 USD/ ton; Electric power: 80 USD/MWh; Carbon tax: 107 USD/ton CO₂ emitted. Figure 5 Option 4: Blue SMRe Renewable electric power to decrease fuel firing in the parallel hydrogen unit

VIEW REFERENCES Omar Bedani