Using industrial waste heat for urban heating networks in Zibo

Zibo, a city with over 4 million inhabitants, is a powerful industrial hub located in Shandong province. The city’s industrial development has long relied on fossil fuels. As Chinese authorities seek to reduce coal dependency and address the growing problem of air pollution, one solution is the recovery of industrial waste heat–a resource that can be used on a massive scale in industrial cities like Zibo.

Heat distribution networks in Zibo have primarily used steam as a heat transfer fluid, which led to significant energy losses. A project to redesign the city’s heating networks has therefore been launched with the support of AFD.

The project enabled the rehabilitation and extension of the city’s heat networks in order to supply a heating area of some 15 million m². The networks are supplied by a cogeneration power plant and waste heat from a petrochemical plant and coking plant in the city.

The project also included the construction of recovery systems using absorption heat pumps and the demolition or shutdown of numerous coal-fired boilers previously in operation in the city.

Finally, existing heat networks were rehabilitated to improve their energy efficiency by replacing steam with hot water as a heat transfer fluid and through network automation.

• Reduction of greenhouse gas emissions by 23,900 tons of CO₂ per year, in keeping with China’s promotion of low-carbon cities;

• Improved air quality;

• 900,000 m³ of water saved each year thanks to the transformation of steam networks into hot water networks and industrial heat recovery.