Zhejiang Branch Kicks Off a Bypass Water Supply Pump Renovation Project, First in China

The bypass recycling water supply pump renovation project for the No.1 generation unit at Ninghai Power Plant under the Zhejiang branch of China Energy began installation on November 1, heralding the start of the China-initiated water supply pump recycling system adaptive renovation project against the backdrop of deep peak shaving of steam turbines.

A repairer welds a bypass pipe.

In recent years, as power plants began to operate in a “deep peak shaving” manner, the usage frequency of water supply recycling control valves has increased significantly. This not only requires better protection of water supply pumps, but also increases the difficulty of their precise peak shaving. Broken valve components threaten the safe operation of generation units. Since the first half of 2018, technicians in Ninghai Power Plant have begun to study the working logic of water supply pumps, obtaining insights into the structures of both domestic and imported valves. Upon surveying relevant valve manufacturers, they acquired relevant testing information for further research of the operating mode and system design rationality of recycling systems. Eventually, they invented a targeted adaptive renovation technology based on the bypass configuration renovation plan. It can perform precise analysis on the operating state, equipment and valve structure, and checking and maintenance of water supply systems of generation units participating in “peak shaving” and solve water leakage inside valves. The technology was implemented in the renovation of the No.1 generation unit in the power plant.

After the renovated project is put into operation, it will generate economic returns ranging from 530,000 yuan to 1 million yuan, reduce coal consumption by 0.08g per kWh, save 400 tons of standard coal and reduce valve repair expense by 210,000 yuan each year. The project has safety, social and economic benefits and is worth promoting.