Hydrogen sourcing for nitrogenous fertilisers:\nWhich routes are commercially used to produce H2 feed for ammonia/urea plants?

Introduction / Context:
Ammonia synthesis (Haber–Bosch) requires a reliable hydrogen source. Fertiliser complexes therefore adopt hydrogen-generation technologies suited to local feedstock availability, energy economics, and scale. This question asks which listed routes are used commercially to supply hydrogen to nitrogenous fertiliser plants.

Given Data / Assumptions:

• We consider proven industrial routes, not laboratory curiosities.
• Plants may be integrated with refineries, steelworks, or stand-alone utilities.
• Regional economics decide which option dominates in a country.

Concept / Approach:
Steam reforming of light hydrocarbons (natural gas, naphtha) is the global workhorse, yielding syngas (H2 + CO/CO2) followed by shift and CO2 removal. Electrolysis of water is also used, particularly where low-cost power is available or for small/remote units. Coke-oven and other off-gases can be cryogenically or chemically separated to recover hydrogen. Hence, all three listed routes are used commercially in various contexts.

Step-by-Step Solution:

Verification / Alternative check:
Plant surveys show dominant adoption of steam reforming, with electrolyzers used in power-rich regions and H2 recovery units in integrated steel–chemicals sites.

Why Other Options Are Wrong:

• Each single-route answer omits other commercially used routes.
• “Coal gasification only” ignores widespread reforming and electrolysis deployments.

Common Pitfalls:
Assuming there is only one “right” technology globally; in practice, feedstock economics and emissions policy drive diverse choices.

Final Answer:
All of the above