7.3.3. Hydrogen Production from Coal without Power Export

In cases where the goal is to produce hydrogen (H₂) from coal without power export, the overall flow arrangement can be further simplified. Figure 3 is a block flow diagram for producing H₂ from coal with minimal power generation. Onsite power generation is kept to a level to meet internal consumption, and if necessary, some power can also be imported. Key differences from H₂ co-production in integrated gasification combined cycle (IGCC) with carbon sequestration (Figure 1) are:

• Eliminating the need for H₂ fired gas turbine (GT) by switching to low or medium Btu fuel-fired boiler plant.
• Changing the pressure swing absorption (PSA) purge compressor to a lower head blower.
• Eliminating the need to compress air separation unit (ASU) waste nitrogen (N₂) for use as diluent.

Table 1 lists some of the published overall performance and efficiency values for coal-to-H₂ production only design studies that correspond to this process arrangement. Results are shown for variations with and without carbon dioxide (CO₂) capture scenarios, and are for minimal power co-production without the use of gas turbines.

Hydrogen

• Why Hydrogen
• Hydrogen & Synthetic Natural Gas from Coal
• Technologies for Hydrogen Production
  • Co-producing H₂ with Current IGCC Technology
  • Co-producing H₂ in IGCC with Carbon Sequestration
  • Hydrogen Production from Coal without Power Export
  • IGCC/H₂ Co-production with WGCU and Advanced WGS Membrane
• Technology for SNG Production
• SNG from Coal: Process & Commercialization
• DOE Supported R&D for Production of Hydrogen