Liquefied natural gas (LNG) containing 85 mol% methane and 15 mol% ethane is stored at 273 K and 260 atm pressure. A process requires 10000 gmol/h of vaporized natural gas at 50 atm and 500 K. To feed this process, the LNG passes through an expansion valve, where the pressure drops to 50 atm, and through a heat exchanger where the temperature increases to 500 K. Saturated steam at 30 bar pressure is condensed to saturated liquid in the heat exchanger to heat the natural gas. Assume that the expansion valve operates adiabatically (Q=0), the change in kinetic energy is negligible, the heat exchanger is well insulated, and the vapor obeys the ideal gas law. What is the condensation rate of the steam (kg/h)?