Hydrogen tube trailers

Gaseous hydrogen delivery pathway via pipelines and tube trailers. (After U.S. Department of Energy Hydrogen, fuel cells and infrastructure technologies program multi-year research, development and demonstration plan, Section 3.2, Hydrogen Delivery, January 21, 2005.)... 

At <10% market penetration, delivery costs from a central plant located some distance from the city are very high. During this period, local production will likely play an important role. Another alternative would be to utilize gaseous tube trailer delivery from nearby central hydrogen production facilities if such facilities exist near or in that urban area. This could be cost-effective if the ultimate tube trailer carrying capacity target of 1100 kg could be achieved. 

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. 

Alkaline electrolysers are at an industrial stage, especially commercialized for on-site production of ultrapure hydrogen for industrial applications. In general, this hydrogen is needed at low to moderate pressure, and the cost demand is set in comparison to the alternative, which is in general the supply by tube trailers. High purity water is fed to the electrolyzer. State-of-the-art commercial alkaline electrolysers typically operate at HHV systems efficiency of 60-75% [44], Current... 

Electrolyzers are today commercially viable only in selected industrial gas applications (excepting various noncommercial military and aerospace applications). Commercial applications include the previously mentioned remote fertilizer market in which natural gas feedstock is not available. The other major commercial market for electrolysis today is the distributed, or merchant, industrial hydrogen market. This merchant market involves hydrogen delivered by truck in various containers. Large containers are referred to as tube trailers. An industrial gas company will deliver a full tube trailer to a customer and take the empty trailer back for refilling. Customers with smaller-scale requirements are served by cylinders that are delivered by truck and literally installed by hand. 

Hydrogen gas can be delivered in a variety of ways, from bulk tankers and tube trailers to cylinders and lecture bottles. 

Hydrogen is currently transported by pipeline or by road via cylinders, tube trailers, metallic hydrides, and cryogenic tankers. For the latter, a small amount shipped by rail or barge is certainly required. At present, hydrogen is produced in a limited number of plants and is used for making chemicals or upgrading fuels. 

Due to the energy intensive nature and the cost associated with hydrogen distribution by high-pressure cylinders and tube trailers, this method of distribution has a range limited to approximately 200 km. The use of metallic hydrides seems to be one of the most promising modes of delivering. However, it is more expensive than hydrogen compression in cylinders. 

For transport and distribution purposes, hydrogen is stored in smaller cylinders at higher pressures. Tube trailers are used to supply industrial users of merchant hydrogen, where the quantities involved are considerable an example is shown Figure 5.2(b). The cylinders are a permanent fixture on the vehicle and are discharged in situ, not off-loaded. Smaller users, such as laboratories, employ cylinders with storage capacities of just a few cubic metres (pressurized to 20 MPa) that can be manhandled with simple trolleys. 

Highway transportation tube trailer with compressed hydrogen gas. 

Transporting compressed gas on the road is state of the art. Compressed gas is shipped either in cylinder trailers or tube trailers (fewer, but bigger single vessels). More and more metal vessels are replaced by others made entirely or partly of composite materials in order to improve the ratio between dead weight and payload somewhat, which is particularly unfavourable for hydrogen. 

Gaseous hydrogen is authorized for shipment in TC/DOT specification cylinders, tube trailers,... 

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