This plant was constructed with the aim of increasing concentrate production and utilizing the recirculating load from the grinding circuits of Concentrate Production Lines 1, 2, and 3. It was commissioned in July 2011 with a capacity of 2 million tonnes per year. In this plant, iron ore lumps, after undergoing three stages of crushing and being reduced to a size of 2 cm, along with the recirculating load from the three concentrate production lines, enter the HPGR (high-pressure grinding rolls) and wet ball mills. After passing through magnetic separation and dewatering processes using belt filters, the final concentrate is produced with less than 8% moisture, a particle size of 300 microns, and a grade of 67–۶۸%. This plant directly employs 193 people.

The fourth concentrate line complex includes a jaw crusher and three cone crushers, which not only supply the required ore for Line 4 but also provide a portion of the iron ore needed for Lines 5, 6, and 7.

Since November 2013, the operation, maintenance, repair, and parts supply contract for this plant and its crushers has been entrusted to Gohar Ravesh Sirjan Company.