A system is provided for vaporizing a cryogenic liquid. The system includes means for producing an exhaust gas by flameless thermal oxidation of a fuel. The system also includes means for transferring heat from the exhaust gas to the cryogenic liquid. The heat transferring means is coupled to receive the exhaust gas from the exhaust gas producing means. The means for producing an exhaust gas optionally includes an oxidizer having a matrix bed, a fuel/air mixture inlet positioned to deliver the fuel/air mixture to the matrix bed, and an exhaust outlet positioned to deliver the exhaust gas from the oxidizer to the heat transferring means. The means for transferring heat optionally includes a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into the receptacle, and a sparger positioned to deliver exhaust gas from the exhaust gas producing means to the receptacle.