Introduction

Hydrogen is a key raw material to other energy intensive industries. Globally, nearly 90% of the hydrogen produced industrially is consumed by the ammonia, methanol and oil refining industries. In the future, hydrogen could play an important role in the decarbonisation of space heating (i.e. industrial, commercial, building and residential heating) and transport fuel (i.e. use of fuel cell vehicles).

Currently, the steam methane reformer (SMR) is the leading technology for H2 production from natural gas or ljosirt hydrocarbons. Modern SMR based hydrogen production facilities have achieved efficiencies that could reduce CO2 emissions down to nearly 10% above its theoretical minimum. Further reduction of CO2 emissions from hydrogen production would only be possible by the integration of CCS.

This study provides an up-to-date assessment of the performance and costs of a modern SMR based H2 plant without and with CCS producing 100,000 Nm3/h H2 and operating as a merchant plant (i.e. standalone plant - without any integration to an industrial complex).

This study presents the economics of deploying CCS in an SMR based hydrogen plant capturing CO2 from the (a.) shifted syngas, (b.) PSA’s tail gas or (c.) SMR’s flue gas. Each capture option was evaluated using IEAHG’s standard assessment criteria against a Base Case (i.e. H2 plant without CCS).

Unlike other studies in the series, the capture of CO2 from an SMR plant is a commercial operation. This is one of the main sources of industrial and food grade CO2 in the market globally. However, only 3 sites around the world have demonstrated the integration of CO2 capture with CO2 transport and storage. These include (a.) Port Arthur Project in the USA, (b.) Quest Project in Canada, and (c.) Tomakomai Project in Japan.

Key Monitoring Discussion Points

• The Base Case consists of: (a.) feedstock pre-treatment, (b.) pre-reformer, (c.) primary reformer, (d.) higher temperature shift reactor and (e.) pressure swing absorption or PSA in single train arrangement producing 100,000 Nm3/h of H2 (purity >99.9%). It consumes about 14.21 MJ of NG and emits about 0.81 kg of CO2 per Nm3 H2 produced.  It has a surplus of ~9.9MWe electricity which is exported to the grid.

• The current industry standard for capturing CO2 from an SMR Based H2 plant is the capture of CO2 from the shifted syngas using MDEA solvent.   Four other CO2 capture options were then evaluated as part of this study.  These include: the use of H2 rich burner in conjunction with capture of CO2 from shifted syngas using MDEA; the capture of CO2 from PSA’s tail gas using MDEA, or the use of Cryogenic and Membrane Separation; and the capture of CO2 from flue gas using MEA.  These options involve the CO2 capture rate in the range of 56% to 90%.

• For all the CCS cases, the addition of the CO2 capture increases the total plant cost by 18% to 79% compared to the Base Case. This corresponds to an additional total capital requirement) of around €40 to €176 million (Q4 2014 estimates).

• For all bar one of the capture options considered, the incorporation of CO2 capture increases the natural gas consumption by 0.46 to 1.41 MJ/Nm3 H2. Similarly, all options with CO2 capture resulted in a reduction of the surplus electricity that could be exported to the grid.  These changes resulted to an increase in the operating cost of hydrogen production by 18% to 33% compared to the Base Case.

• Adding CCS to an SMR based H2 plant results to an increase in the Levelised Cost of Hydrogen between € 0.021 and € 0.051 per Nm3 H2 (from € 0.114 per Nm3 for the Base Case).  This corresponds to a CO2 avoidance cost (CAC) of between €47 and €70 per tonne of CO2.