Storage and transportation of liquid hydrogen is the basis of safe, efficient, large-scale and low-cost application of liquid hydrogen, and also the key to solve the application of hydrogen technology route.
 
The storage and transportation of liquid hydrogen can be divided into two types: container storage and pipeline transport. In the form of storage structure, spherical storage tank and cylindrical storage tank are generally used for container storage and transportation. In the form of transportation, liquid hydrogen trailer, liquid hydrogen railway tank car and liquid hydrogen tank ship are used.
 
In addition to considering the impact, vibration and other factors involved in the process of conventional liquid transportation, due to the low boiling point of liquid hydrogen (20.3K), small latent heat of vaporization and easy evaporation characteristics, the container storage and transportation must adopt strict technical means to reduce heat leakage, or adopt non-destructive storage and transportation, to reduce the degree of vaporization of liquid hydrogen to the minimum or zero, otherwise it will cause tank pressure boost. Lead to overpressure risk or blowout loss. As shown in the figure below, from the perspective of technical approaches, liquid hydrogen storage and transportation mainly adopt passive adiabatic technology to reduce heat conduction and active refrigeration technology superimposed on this basis to reduce heat leakage or generate additional cooling capacity.
 
Based on the physical and chemical properties of liquid hydrogen itself, its storage and transportation mode has many advantages over the high-pressure gaseous hydrogen storage mode widely used in China, but its relatively complex production process also makes it have some disadvantages.
 
Large storage weight ratio, convenient storage and transportation and vehicle
Compared with gaseous hydrogen storage, the biggest advantage of liquid hydrogen is its high density. The density of liquid hydrogen is 70.8kg/m3, which is 5, 3 and 1.8 times that of 20, 35, and 70MPa high-pressure hydrogen respectively. Therefore, liquid hydrogen is more suitable for large-scale storage and transportation of hydrogen, which can solve the problems of hydrogen energy storage and transportation.
 
Low storage pressure, easy to ensure safety
Liquid hydrogen storage on the basis of insulation to ensure the stability of the container, the pressure level of daily storage and transportation is low (generally lower than 1MPa), much lower than the pressure level of high-pressure gas and hydrogen storage and transportation, which is easier to ensure safety in the daily operation process. Combined with the characteristics of large liquid hydrogen storage weight ratio, in the future large-scale promotion of hydrogen energy, liquid hydrogen storage and transportation (such as liquid hydrogen hydrogenation station) will have a safer operation system in urban areas with large building density, dense population and high land cost, and the overall system will cover a smaller area, requiring smaller initial investment cost and operation cost.
 
High purity of vaporization, meet the requirements of the terminal
The global annual consumption of high purity hydrogen and ultra-pure hydrogen is huge, especially in the electronics industry (such as semiconductors, electro-vacuum materials, silicon wafers, optical fiber manufacturing, etc.) and fuel cell field, where the consumption of high purity hydrogen and ultra-pure hydrogen is particularly large. At present, the quality of many industrial hydrogen cannot meet the strict requirements of some end users on the purity of hydrogen, but the purity of hydrogen after vaporization of liquid hydrogen can meet the requirements.
 
Liquefaction plant has high investment and relatively high energy consumption
Due to the lag in the development of key equipment and technologies such as hydrogen liquefaction cold boxes, all hydrogen liquefaction equipment in the domestic aerospace field was monopolized by foreign companies before September 2021. Large-scale hydrogen liquefaction core equipment is subject to relevant foreign trade policies (such as the Export Administration Regulations of the US Department of Commerce), which restrict the export of equipment and prohibit technical exchange. This makes the initial equipment investment of hydrogen liquefaction plant large, coupled with the small domestic demand for civil liquid hydrogen, the scale of application is insufficient, and the capacity scale rises slowly. As a result, the unit production energy consumption of liquid hydrogen is higher than that of high-pressure gas hydrogen.
 
There is evaporation loss in the process of liquid hydrogen storage and transportation
At present, in the process of liquid hydrogen storage and transportation, the evaporation of hydrogen caused by heat leakage is basically treated by venting, which will lead to a certain degree of evaporation loss. In the future hydrogen energy storage and transportation, additional measures should be taken to recover the partially evaporated hydrogen gas to solve the problem of utilization reduction caused by direct venting.
 
HL Cryogenic Equipment
HL Cryogenic Equipment which was founded in 1992 is a brand affiliated to HL Cryogenic Equipment Company Cryogenic Equipment Co.,Ltd. HL Cryogenic Equipment is committed to the design and manufacture of the High Vacuum Insulated Cryogenic Piping System and related Support Equipment to meet the various needs of customers. The Vacuum Insulated Pipe and Flexible Hose are constructed in a high vacuum and multi-layer multi-screen special insulated materials, and passes through a series of extremely strict technical treatments and high vacuum treatment, which is used for transferring of liquid oxygen, liquid nitrogen, liquid argon, liquid hydrogen, liquid helium, liquefied ethylene gas LEG and liquefied nature gas LNG.