On September 21, 2020, ALROSA commissioned a thickening complex for remediating tailings at the processing plant no. 12 of the mining and processing division at Udachny.

The project, which will cost more than three billion rubles, will significantly reduce water consumption and increase the efficiency of overburden storage, simplifying the handling of the waste rock left over from the processing of kimberlite.

The tailings thickening complex consists of a pump system, a cyclone cluster, and two large tanks, each with a diameter of 28 meters. The complex uses centrifugal power to extract most of the recycled water from the tailings. The water continues to be used and the remaining sand after thickening is sent to a landfill site.

The project will allow for a modification of the overburden storage system and a significant extension of the life of the existing landfill.

The thickening of the tailings makes production more environmentally friendly and reduces the water consumption of the processing plant by 85 percent. “Previously, around 6,500 to 7,000 cubic meters of water per hour was consumed. Today only 1,000 cubic meters per hour are needed, with the rest being filled with recycled water. Simultaneously, using cone-based thickened tailings will enable the safe use of the existing landfill site until 2066,” noted Roman Deniskin, head of the mining and processing department at Udachny.

The realization of the project took several years, with the investments amounting to about 3.3 billion rubles.

The complex became the second project of its kind. Previously, an alternative method of thickening waste using other technologies was introduced at the processing plant no. 16 at the Nyurba mining and processing area.

ALROSA consistently reduces the environmental impact and risks associated with the operation of tailings dumps. Today, the company is developing a project for drainage and rehabilitation of waste dumps at the wastewater treatment plant no. 8 at the Aikhal mining and processing division.

According to a PwC study from 2019, ALROSA is the leader in circulating and re-using water.

In 2019, the volume of recycled and reused water was 4.1 million cubic meters, or 55 percent of total water consumption. The total volume of circulated and reused water in the process cycle was 222.4 million cubic meters. Within three years, the total volume of circulating water supply at ALROSA grew by 40.5 percent.