Hydrogen transportation liquefied

Seamless steel pressure vessels are the most common method in use today for hydrogen transportation at short distances (<200 km) and when small quantities are involved (up to about 500 kg). The different vessel options include cylinders, manifolded cylinder pallets and tube trailers. While single cylinders or manifolded pallets are trucked to the destination and off loaded, tube trailers, which consist of several steel cylinders mounted to a protective framework, are often left in place and replaced when empty. Transporting hydrogen in liquefied form is seven times more efficient in terms of actual hydrogen weight transported than using compressed gas cylinders. 

The total cost per kilogram of liquefied hydrogen transported by rail can be determined in the same way that it is for compressed gas and metal hydrides, while accounting for the losses due to boil-off. 

Therefore, the total cost per kilogram of transporting liquefied hydrogen by ship can be found in the same way that other transportation costs are determined, dividing the annual cost over the annual production while accounting for boil-off. 

Hydrogen transportation requires special pipelines and transportation in liquefied or pressurized hydrogen vessels, possibly by train or truck. If the decision to make a transition to a hydrogen economy is adopted at some point in the future, a careful plan will be needed, possibly including an initial phase characterized by underutilized infrastructure. Co-opting the present natural gas infrastructure remains an open issue as it will probably be unsuitable (Adams et al., 2005). 

After the recovery of natural gas liquids, sweet dry natural gas may be liquefied for transportation through cryogenic tankers. Further treatment may be required to reduce the water vapor below 10 ppm and carbon dioxide and hydrogen sulfide to less than 100 and 50 ppm, respectively. 

At the exit of the WGS reactor, the reacted CaC03 particles are captured by a high-temperature cyclone and the spent solids are then sent to a rotary calciner to thermally decompose the CaC03 back to CaO at temperatures between 660°C and 900°C with pure C02 formed in the outlet gas stream. The pure C02 gas can be economically compressed, cooled, liquefied, and transported for its safe sequestration. Hydrogen can be used for various energy conversion systems or hydrogen-enriched fuel production without any further low-temperature cleanup requirement. 

Demirbas, A. 2002. Enel properties of hydrogen, liquefied petroleum gas (LPG), and compressed natural gas (CNG) for transportation. Energy Sources 24 601-610. 

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