Cause Analysis of Fouling in Steam Turbine

　　In a thermal power plant, steam turbine rotates driven by the steam, which drives generator to generate electricity. Since there are impurities in the steam, some of these impurities will be deposited on the blades of steam turbine, nozzles of baffle and other flow parts during the long-term operation of steam turbine. There are generally two ways for impurities to deposit: one is to deposit in the form of scale, this part of deposit is insoluble in water, and is more firmly combined with metal surface, and its texture is relatively hard. The other is attached to metal surface in the form of attachments, and its components are iron oxides and some other inorganic salts. For example, under same soda quality conditions, the higher the grade parameter of general unit, the more sediment will be, and the harder it will be. Due to deposits, the originally set steam flow area and cut-in angle of steam turbine change, which leads to an increase in the amount of steam consumed by the steam turbine per unit of power generation or an increase in heat consumption per unit of power generation.

　　In severe cases, it will affect the efficiency of steam turbine. Taking a 300MW thermal power generation steam turbine unit as an example, if steam consumption increases by 1%, it means tens of thousands of CNY of economic losses every day.