In this study, the effect of Poisson's ratio of microscopic structure on coke strength is numerically investigated using a homogenization method. In the analyses, microscopic structure of coke is composed of active components and pores. The stress analyses are carried out for cokes with different Poisson's ratio of microscopic structure and pore shapes in roundness. The analytical results are summarized as follows: - The differences in Poisson's ratio hardly affect microscopic stress distributions. - It is thought that the effect of Poisson's ratio on maximum stress is small. - Homogenized elastic modulus increases with the rise in Poisson's ratio. However, the difference in homogenized elastic modulus becomes small with an increase in porosity. - Considering porosity of coke is generally about 50 %, Poisson's ratio has little influence on coke rigidity.
The LNG heat storage system for liquid hydrogen production system of 10,000Nm3/h was investigated. The LNG enthalpy change for vaporization is used to save energy of the compressor for the recycle hydrogen of liquid hydrogen process. As the LNG cannot be used in the night-time, its cold energy is accumulated in the day-time and it is released in the night-time. The screening test concerning the cold energy storage medium by DSC (Differential Scanning Calorimetry) measurement and the elemental experiment of the cold energy storage system of 0.2 m3 were carried. The feasibility study about the present hydrogen production system was performed, and it was concluded that the cost for hydrogen production is reduced from 4% to 8% and the energy for hydrogen production is reduced from 30% to 40%.