A fuel oil is burned with the air in a boiler furnace. The combustion forms 812 kW of thermal energy, of which 65% is transferred as heat to boiler tubes that pass through the furnace. The combustion products pass from the furnace to as tack at 650 degrees Celsius. Water enters the boiler tubes as a liquid at 20 degrees Celsius and leaves the tubes as saturated steam at 20 bar absolute. Determine the rate at which the steam is formed. Calculate the volumetric flow rate of the steam produced.