Hydrogen sulfide is produced by reacting hydrogen (in this case, from the M2H unit) with molten sulfur at elevated temperatures. H₂S is used to make mercaptans, other downstream chemicals and for mining and metallurgy applications. The balance of the hydrogen from the M2H unit will be used for other applications.

The heart of the M2H 1,000 process consists of an oil-heated multi-tube methanol reformer. A controlled mixture of methanol and demineralized water is pumped into the top of the reformer. The resulting hydrogen-rich synthesis gas is fed into a multi-column pressure swing adsorption (PSA) unit to yield 99.99% pure hydrogen.

Using methanol to make hydrogen for decentralized operations is an option when pipeline natural gas or LPG are not readily available. Methanol is an internationally traded liquid product that can be easily transported to remote points of use by truck or train. Its low cost and availability make it an attractive energy vector, Unitel suggests.

Unitel’s M2H 1,000 represents a significant departure from the conventional natural gas reforming process. In addition to selective supply chain advantages, lower capital and operating costs are the most visible benefits.

—Serge Randhava, CEO of Unitel

Other advantages of the Unitel M2H 1,000 design versus conventional natural gas steam reforming at this scale are:

• Higher overall efficiency.
• Simpler metallurgy without any exotic materials.
• Internal heat generation in lieu of indirect heat transfer.
• Rapid start-up.
• Faster dynamic response and better turn-up and turn-down capabilities.
• Reduced NONO_xx emission problems.

Small-scale self-contained hydrogen plants offer a substitute to piped hydrogen and tube trailers for a variety of low-volume applications in industries such as electronics, steel, food, chemicals, pharmaceuticals and glass. Hydrogen fueling and fuel cells are also potential future uses.