Technology overview and suitability for hydrogen in India

The major end uses in India is from fertilizer (ammonia), chemicals (methanol) and oil refineries. It has demand from transportation and power generation and grid balancing at very nominal levels and is expected to increase by end of 2030.

Technology Overview

• Mature technology and widely used across the refining and petrochemical industries
• Improvements have included higher performing materials, improved heat recovery, lower pressure drop and higher conversion catalysts
• Typical capacities ~20 MMSCFD (22 kNm3 /h or 74 MW H2 HHV) to world scale capacities of 150 - 200 MMSCFD (168 - 224 kNm3 /h or 564 – 739 MW H2 HHV)
• Example large scale proven single train SMR plants:
Grayville, USA: 120 MMSCFD (134 kNm3 /h or 450 MW H2 HHV)
Baton Rouge, USA: 120 MMSCFD (134 kNm3 /h or 450 MW H2 HHV)

Carbon capture from SMR hydrogen production

• Two main sources of CO2 production:
CO2 produced from the chemical reactions of the process
CO2 production from the combustion of the fuel that is required to provide heat for the endothermic process reactions
• Source 1) relatively easy to capture as a high purity stream, especially using an amine solvent
• Source 2) relatively difficult (i.e. expensive) to capture, due to diluted concentration of CO2 and pressure at atmospheric condition
• Carbon capture solutions that aim to recover both sources are much more capital intensive than those that focus just on Source 1)
• The AFW Case 3 captures the CO2 from the Flue gas

SMR Case - Flow Scheme

SMR Case - Plant Boundaries

Technology Overview

• In the ATR technology, part of the natural gas feed is partially combusted to generate heat for the endothermic reforming reaction. This self-heating (‘auto-thermal’) mechanism largely eliminates the need for any external heating, which can be met with supplemental hydrogen firing.

• The H2 /CO ratio from ATR technology is less suited to hydrogen production than SMR, more suited to Fischer–Tropsch processes, so technology has to be “re-optimized” for hydrogen production.

• Numerous ATRs are in operation worldwide, but most operate as secondary reformers in ammonia plants in collaboration with SMR technology. For ammonia plants, stand-alone ATR technology has so far been considered uneconomical. For methanol plants, only a few true stand alone ATRs have been realized up to now, but ATR technologies are maturing steadily.

• The high CAPEX cost of capturing CO2 from SMR flue gas makes the use of ATR more attractive for “blue” hydrogen production, especially if CO2 capture rates >90% required.

Carbon capture from ATR hydrogen production

• On the positive side, use of oxygen instead of air for natural gas combustion avoids the need for expensive post- combustion separation of CO2 from nitrogen.

• On the negative side, the ATR technology requires an Air Separation Unit (ASU) which commands high CAPEX as well as OPEX due to associated additional power demand.

• If a portion of the hydrogen produced is used as fuel to generate power to meet the plant’s power requirement, CO2 capture rates of 95% can be achieved with ATR technology (versus 90% maximum for SMR technology).

• This makes ATR particularly attractive where there is low carbon grid factor electricity available. Where internal power demand has to be self-generated, higher CO2 capture rates can only be maintained by using hydrogen as combined cycle gas turbine fuel.

ATR Case - Flow Scheme