Tag Archives: Alrosa

ALROSA looks to reclaim Aikhal tailings pit as part of 650 ha land restoration project

ALROSA plans to reclaim the tailings pit of processing plant No. 8 at its Aikhal Division by 2029 in a project worth over RUB2.5 billion ($34.3 million) that will seek to restore 650 ha of land and have it planted with pine forests, the diamond miner says.

The tailings pit is located 1.2 km southwest of the village of Aikhal (pictured) in the Sokhsolookh River valley in Yakutia, Russia. The decision to reclaim the facility followed the completion of mining at the Komsomolsky open pit and the closure of processing plant No. 8 at the end of 2020.

During the plant’s operations, tailings were stored in the tailings pit as a liquid slurry. In terms of environmental danger, the slurry belongs to the lowest hazard waste category (virtually non-hazardous waste or category 5 under the Russian Federal Law on Industrial and Consumer Waste), ALROSA says. The tailings pit was a key hydrotechnical facility ensuring water recirculation at the processing plant: after the slurry settled in the pit, clarified water was fed back into the plant to be re-used in processing diamond ore, the company explained.

The reclamation project will be implemented in two stages.

The first stage will include draining the pit and restoring a part of the original course of the Sokhsolookh River back to its natural state.

Later on, from 2025 to 2029, the tailings facility will be dismantled, and work will be carried out to improve the land, dig drainage ditches, install waterproofing, lay fertile soil and landscape the area. To achieve this, 160,000 Scots Pine seeds have been sown in 2021 in a disused sand and gravel open pit not far from the Aikhal village. This conifer is not native to this area and does not grow locally on its own.

Once all the work is complete, the land beneath the tailings pit will be restored to its original condition and, as mentioned, over 650 ha of replanted area will be handed over to local authorities.

ALROSA shores up tailings dump safety with automated wireless monitoring

ALROSA says it has approved the introduction of automated wireless monitoring systems at the hydraulic structures of its tailings dumps as it looks to further reduce the risk of emergencies, improve operational safety of the structures and facilitate the accumulation of data on their operations for future analysis.

The automated wireless monitoring system (AWMS) consists of a network of sensors installed at the existing observation wells of the hydraulic structures (HS) at tailings dumps, and serve to provide early warnings in case of deviation from safe parameters, the diamond-focused company said.

The system monitors all key parameters of a hydraulic structure, including water levels in open reservoirs, water pressure in wells and soil temperature.

Konstantin Kolegov, ALROSA’s Deputy Chief Engineer for Hydraulic Structures, said: “Industrial and environmental safety is our top priority. The company’s dedicated units gather the HS data according to the schedule. The AWMS minimises the human error factor and reduces the risk of emergencies at HS, including tailings dumps and hydraulic power systems, as it can send real-time alerts of changes in key parameters. Moreover, the system, which was first introduced last year at Aikhal Division, will help accumulating and analysing data on the condition of hydraulic structures to optimise their performance.”

Cutting-edge technologies provide an opportunity to source the necessary information much faster and frequent compared with manual monitoring, ALROSA said. Thanks to the Manufacturing Execution System integration, the collected data will become available to all required personnel in the company.

During the first stage of implementation in 2020, the equipment was installed and commissioned at the tailings dump of processing plant No. 14 at Aikhal Division. Stage two provides for the AWMS to be installed at two tailings dumps of processing plant No. 12 of Udachny Division in 2021, and at two facilities of Nyurba and Mirny (open pit, pictured) Divisions in 2022. Following this, the system will be expanded to include the remaining hydraulic structures in Mirny, Udachny, Aikhal and Nakyn.

Total investments during the two stages are estimated at around RUB 100 million ($1.3 million), ALROSA said.

ALROSA looks to ABEL HM pumps for filter press feeding

Piston diaphragm pumps from ABEL are helping Russia’s ALROSA with its filtration process at one of its diamond mines in the country.

In Spring 2021, ABEL received an order for the delivery of six of these piston diaphragm pumps, HM pumps, following an initial HM pump order in 2020. This inaugural pump was delivered to ALROSA in February 2020 as replacement for a centrifugal pump previously used for filter press feeding. At the beginning of August, the ABEL pump was commissioned at the diamond producer’s plant. The dewatering result (higher solids content, shorter filtration time) was so convincing that ALROSA decided to feed all filter presses in this plant with the pumps, ABEL said.

The latest delivery is being facilitated by ABEL’s official distributor in Russia, SibComplectService.

ABEL’s HM pumps are available as single- or double-acting versions. They come with a high flow rate, reliable function and particularly low operating and maintenance costs, the company says.

In addition to filter press feeding, the hydraulic diaphragm pumps are also used for sludge transport, spray dryer feeding, rotary kiln feeding, autoclave feeding, and sealing/rinsing water supply, among other applications.

ALROSA weighs up restoration and closure options at Mir underground diamond mine

Following the analysis of several options for deposit opening and deep level development, ALROSA has laid out plans regarding restoration or full closure of the currently suspended Mir underground mine in the Far East of Russia.

ALROSA said the concept requires deep level exploration down to -1,300 m to confirm the mine’s reserves. These activities are scheduled to be completed by early 2022. Budgeted at around RUB2 billion ($31 million), this work is included in the group’s RUB28.7 billion capital expenditure programme for 2019.

Last year, the company suspended the construction of deep mine levels below the level -800 m where it was necessary to carry out works to prevent gas-dynamic phenomena recorded there, ALROSA said.

Based on the results of the exploration works, pilot holes will be drilled to start preparation of deposit opening design documents (within one to two years). This work is to be completed before 2024.

“Simultaneously, the company will carry out conceptual design activities to ensure water disposal at the mine and choose the best mining technology as well as ventilation and gas safety options,” ALROSA said.

If it is decided that the restoration of the Mir underground mine is feasible, the construction is estimated to take six to eight years.

“In summary, Mir mine restoration can start no earlier than 2024 and only if the studies yield positive results, and if it is confirmed that construction and mining can be done with the highest level of occupational safety,” ALROSA said.

“ALROSA’s decision about further development of this mine will be based solely on safety considerations and economic viability.”

Geobrugg slope stability system ups protection ante at Alrosa’s Aykhal diamond mine

Geobrugg has recently installed nails, mesh and spike plates as part of a slope stabilisation system at Alrosa’s Aykhal diamond operation in Mirninskiy Ulus, Russia.

Aykhal is in the permafrost region of Russia, a fact that comes with hazards – for two to three months of the year, rockfalls can occur as a result of melting permafrost. This makes it difficult and, potentially, dangerous for the trucks and operators that come in and out of the underground mine portal and navigate around the former open-pit mine site.

Some conventional wire mesh was widely used at the operation, until now, to safeguard the portal, according to Geobrugg. “As this mesh did not provide enough safety and has to be changed every two-to-three years, Alrosa decided to test Geobrugg state-of-the-art technology,” the company said.

For the protection solution, Geobrugg’s TITAN 40/16 nails with TECCO® G65/3 mesh and P33/50 spike plates were employed. In total, an area of 1,400 m² of mainly fractured dolomite with an unstable layer from 1.1-1.5 m was stabilised, according to Geobrugg. The installation on a 70-85º slope took one month and a Geobrugg Supercoating® was employed for corrosion protection, the company said.

Geobrugg said: “One of the challenges was the delivery of material and drilling machinery to the site: In winter time, you may use the ice road which runs along the river Lena. In the summer, material has to be delivered by ship, which takes one-and-a-half months from the European part of Russia to this site.”

Installation had to be carried out during the short period when temperatures were above freezing – mid-May to mid-September – Geobrugg said.