The contract for a 58MW grinding circuit, with horizontal and vertical grinding mills, also includes process automation technology, and installation and commissioning services.
Metso Outotec said the sale would bolster its 2020 third-quarter orders.
The company's minerals business president, Stephan Kirsch said the merger of Metso and Outotec, completed on July 1 this year, had strengthened the combined group's local business presence, "which will be of great benefit to the implementation of the project".
"Our solutions will help Zijin Mining in their quest to create a sustainable world-class operation with high productivity and cost effectiveness," he said.
The new grinding circuit will reportedly increase Qulong's daily concentrator ore handling capacity to 150,000 tons.
Metso Outotec (HEL: MOCORP) finished trading Monday at EUR5.92, giving the company a market value of EUR4.91 billion.