Commission problems and countermeasures of integrated membrane technology in boiler make-up water system of a power plant

Based on the technical renovation project of boiler make-up water system in a power plant in North China，the design characteristics and operation mode of ultrafiltration-first stage reverse osmosis-second stage reverse osmosis-electrodeionization（EDI） integrated membrane technology were introduced. The typical problems in different commissioning conditions of each main processing unit were analyzed，such as start-stop，normal operation，backwash，chemical cleaning，dosing and maintenance washing. The corresponding solutions and precautions were given from the aspects of pipeline design，control strategy and commissioning parameters. The long-term operation results after commissioning showed that the whole process system operated stably，the water index was qualified，and the conductivity was less than 0.1 μS/cm，silicon mass concentration was less than 10 μg/L，TOC was less than 200 μg/L. The economic benefits analysis showed that the new boiler feedwater system reduced the environmental pressure on the power plant， saved water intake costs，and the operating cost per ton of water was about 4.3 yuan. The operation and maintenance cost was relatively low，which could improve the quality and efficiency of the chemical water production system in the power plant.