On November 1, 2018, some water samples of NO.1 unit were collected on site for analysis, and only chloride ion content analysis was conducted. The sampling parts are as follows: Water sample at economizer inlet; Main steam outlet steam; Water sample at condensate outlet; Water sample at condensate polishing outlet.The chloride ion content of all parts meets the requirements of operation and maintenance manual for fine treatment of power plant and GB/T 12145-2016 Water and steam quality standard for thermal power generating units and steam power equipment (< 1 μ g / L).