China National Nuclear Corporation (CNNC) has started commissioning China's first industrial-use nuclear energy steam supply project at the Tianwan NPP in Jiangsu province. The project is set to deliver steam to a nearby petrochemical plant, demonstrating a novel application of nuclear energy beyond electricity generation.

The project involves CNNC's subsidiary, Jiangsu Nuclear Power Company, and the Lianyungang Petrochemical Industry Base in Xuwei New District, Lianyungang City. Steam from the secondary circuits of units 3&4 at the Tianwan NPP will undergoing multi-stage heat exchange and then transported via an insulated pipeline to the Lianyungang Petrochemical Industrial Base.

The Tianwan project uses a complex pipeline network spanning approximately 23.36 kilometres – the longest ever transmission path for a nuclear energy heat supply. The NPP is equipped with four steam conversion devices and will produce industrial superheated steam at a pressure of 1.8 MPa and a flow rate of 600 tonnes per hour. The supply of 4.8m tonnes of steam a year will substantially reduce the consumption of coal by 400,000 tonnes year and cut emissions, including an annual reduction of 1.07m tonnes of carbon dioxide, 184 tonnes of sulphur dioxide, and 263 tonnes of nitrogen oxides.

During commissioning, comprehensive testing will continue between the NPP and the steam's off-site users, including preheating and purging of the steam pipeline. A stable steam flow rate of 280 tonnes per hour has already been recorded and commercial operation is scheduled for June. The total investment in the project is CNY730m ($109,5m).

Tianwan NPP comprises eight units. Units 1-4 (Phases I and II), which began commercial operation between June 2007 and December 2018, are Gidropress VVER-1000 units supplied by Russia. Phase III (units 5 & 6, are ACPR1000 reactors. Tianwan 5 began commercial operation in 2020 and unit 6 in 2021. Phase IV (unit 7&8) are under construction and will be Russian supplied VVER-1200 units.