Activated carbon fiber composites for ammonia, methane and hydrogen adsorption

Abstract

Complex compound material (activated carbon fiber, saturated with salts, or metal hydrides) was developed as an efficient gas (ammonia, methane, hydrogen) adsorbent for new gas storage and transportation system application. To enhance the performance and thermodynamic efficiency of the gas storage vessels a heat pipe thermal control system was suggested. Nomenclature a adsorption capacity kg/kg a v volume capacity of hydrogen storage using physisorption m 3 /kg C density of free gas kg/m 3 C solid sorbent specific heat capacity J/(kg·K) C g specific heat capacity of free gas J/(kg·K) C a specific heat capacity of adsorbed gas J/(kg·K) E activation energy J/kg G gas output from the cylinder kg/sec g i gas output from the elementary cell, used for computer modeling kg/sec K s0 pre-exponent constant in the equation of kinetic of sorption s −1 M mass of the gas in the cylinder kg M i mass of the gas in the calculated cell kg N number of calculated cells in the cylinder P pressure Pa, MPa q st latent (isosteric) heat of sorption J/kg Q heat flow W r, z cylindrical coordinates m R external radius of the cylinder shell m R 0 internal radius of the heat pipe m r 0 , r internal and external radii of the annular layer of the sorbent m R m gas constant J/(kg·K) R p mean radius of the particles m 2S finning step m T temperature K, °C W 0 maximum microporous specific volume m 3 /kg v component of the velocity vector m/sec v a specific volume of adsorbed medium m 3 /kg