In the process of milk powder production, a large amount of steam is required in various process steps such as sterilization, concentration and drying. ZOZEN provided several sets of SZS series gas-fired steam boilers for this milk powder company. This series of gas-fired boilers adopts water-cooled full-membrane wall structure and conducts air-tightness test before heat preservation to ensure that the boiler has no cross-smoke phenomenon during micro-positive pressure combustion, which also helps to reduce heat loss from boiler body; the large-volume furnace design is equipped with the European low NOx burner, which effectively reduce the formation of NOx and achieves ultra-low NOx emissions.