I would like to know how much heat energy liquid nitrogen contains per lb. In other words, per lb. of liquid, how many BTUs of heat would N2 absorb in the process of coming up to about 60F? I want to capture the cold energy of nitrogen as it vaporizes and store that cold energy for another purpose, essentially building a thermal bank with the cold, for metering into water. Can you assist me in figuring out the btu potential on one side per gallon of N2 vaporized for injection into food product packaging?