Veolia (Harbin) Thermal Power Co., Ltd. was established in 2003 and is a Sino-foreign joint venture controlled by Veolia Group. ZOZEN customized a complete boiler system including multiple sets of WNS series gas-fired hot water boilers. This series of gas-fired boilers adopts full corrugated furnace to increases the strength and elasticity of the furnace and enhances the disturbance of the flue gas, effectively improving the heat transfer effect. The threaded fire tubes can effectively absorb the flame energy, and the heat transfer coefficient is 1.2 times higher than that of the ordinary tube. At the same time, the finned tube condenser added at the end of the flue can increase the boiler thermal efficiency to over 98%