The underground X-ray Transmission (XRT) sorting pilot plant on the Zielitz mine, developed by TOMRA in collaboration with Okay+S, TOMRA says units a brand new benchmark for environment friendly, sustainable potash mining. The pilot venture, which has been operating since 2022, has efficiently addressed its primary goal of eradicating barren waste underground, with the potential of decreasing stockpiling and bettering ore grade of hoisted materials by the shaft, whereas enhancing total operational effectivity. The venture is ongoing, exploring methods to optimise the separation efficiency, enhance throughput and implement the brand new expertise into the mine planning course of.
TOMRA Mining and Okay+S Minerals and Agriculture have reached a serious milestone of their ongoing technological collaboration on the Zielitz mine in Germany with the profitable underground sorting pilot plant for rock salt pre-separation. The venture goals to minimise stockpiling, scale back the bottleneck on the mineshaft, and accommodate additional mine growth. The underground pilot plant is supplied with a TOMRA XRT sorter specifically tailored to attain Okay+S’s goals – a singular resolution particularly developed for the mine’s situations and necessities.
This pilot venture is the newest improvement within the long-standing collaboration between TOMRA and Okay+S, Europe’s main salt producer and a worldwide provider of potash minerals. Their collaboration started in 1998, when the primary TOMRA color sorter was put in on the Braunschweig-Lüneburg website at Grasleben. Through the years, the 2 corporations have labored collectively on quite a few tasks and performed in depth testing for numerous crops.
Okay+S initiated the venture as a part of its concentrate on figuring out sensible, long-term options to enhance sustainability and improve productiveness in its manufacturing and provide chains. The corporate partnered with TOMRA to discover methods of eradicating barren waste underground, considerably decreasing stockpiling – therefore decreasing the mine’s environmental impression – and bettering grade by the shaft.
“The dealing with of backfill has been an essential situation in mining for many years. The ever-increasing calls for of deeper and extra complicated deposits, the financial necessity for economies of scale and rising environmental laws should be met. The lean manufacturing method of eradicating nugatory minerals from the fabric stream as early as attainable and additional processing the precious minerals in a concentrated type guarantees quite a few benefits,” mentioned Dr Isabell Pfaffe and co-authors in a current technical paper on the venture.
The sorting plant was put in underground and commissioned in 2022. It options TOMRA’s XRT expertise to determine and take away waste materials – predominantly halite (NaCl) – with a potassium (Okay2O) content material under 2%.
By sorting the mined materials underground to take away waste materials and redirect elements of it for backfill, the pilot plant efficiently addresses the three key challenges on the Zielitz website. The primary one is stockpile discount: as the big amount of stockpiled materials implies a serious environmental safety effort. By way of this venture, Okay+S goals to discover a resolution to scale back the quantity of barren materials going to the stockpile as a lot as attainable. The second is the bottleneck on the mineshaft: the principle shaft hoists as much as 45,000 t per day, leaving no capability for future growth or return of processed waste underground. Lastly, the venture goals to resolve infrastructure constraints in view of a future mine extension deliberate over 40 km, as there isn’t any transport capability or amenities to return processed waste as backfill into the mined-out areas.
For the Zielitz pilot venture, TOMRA developed a singular resolution primarily based on a TOMRA COM XRT 2.0 1200 sorter that includes a sensing system tailored with setup and algorithms specifically designed to attain the targets set by Okay+S. The method begins with a feed system outfitted with an adjustable stream divider on the primary belt, which directs the uncooked salt feed to a double-deck vibration display. The fabric is separated into outlined dimension fractions, and the oversize and undersize fractions are returned to the principle belt. The display mats are interchangeable, permitting operators to strive totally different dimension ranges. As soon as screened, the fabric is conveyed to the XRT sorter, which identifies potash rocks and removes undesirable sodium salt, which has a decrease atomic density. The fabric recognized as waste, with a potassium content material under 2.0%, is diverted to a conveyor for backfill, whereas the focus is fed again to the principle belt and from there to the shaft.
The set up of the pilot sorting system underground got here with its personal set of logistical challenges, most notably transporting the 18 t XRT sorter by the shaft. The machine needed to be rigorously disassembled, lowered in parts and reassembled onsite. TOMRA’s expertise within the underground set up of sorting gear was extraordinarily worthwhile in efficiently addressing this problem along with the Okay+S personnel on website.
The pilot venture has efficiently achieved all of the goals and has demonstrated that the TOMRA XRT sorter can efficiently take away liberated halite. The pilot plant at present processes 50 t per hour. It removes as much as 50% of the feed as barren rocks underground, decreasing the load to the shaft and permitting for a rise in mining capability. A part of the barren waste, which has a potassium content material under 2.0%, is used as backfill, decreasing the quantity going to stockpile. The remaining 50% of the feed, with a virtually doubled ore grade in comparison with the earlier set-up, is mixed into the principle materials stream to the shaft and hoisted to the processing plant.
With the profitable outcomes achieved by the pilot plant, the businesses are trying on the subsequent section: exploring the scaling up of capability and integrating TOMRA’s AI-powered expertise, OBTAIN. This groundbreaking expertise leverages Deep Studying to precisely determine the properties of every particular person particle, even when they’re bearing on the belt – consequently, regardless of the sorter’s capability – attaining unparalleled precision and reliability. The result’s single-particle precision in high-throughput ore sorting.
“Our imaginative and prescient of what might be achieved in an extra stage, introducing extra sorters with OBTAIN, is to kind as many tons of ROM as attainable. The sorted waste, which is about half of the sorter feed, is used for backfilling, and the remaining quantity of high-grade product is conveyed to the shaft,” explains Jens Michael Bergmann, International Phase Supervisor Industrial Minerals at TOMRA Mining. “The purpose is to additional enhance the Okay2O grade on the shaft, which can imply hoisting the identical tonnage however at the next grade sooner or later. This can mechanically scale back stockpiling, and the downstream processing steps on the floor installations shall be extra environment friendly as a result of greater potassium grade of the hoisted uncooked materials. We’ve began testing OBTAIN to see how a lot we are able to enhance the sorter capability whereas sustaining the identical efficiency. The preliminary trials on the TOMRA take a look at middle have proven very promising outcomes.”
The Zielitz pilot plant venture has already attracted the curiosity of different mining corporations with comparable conditions and environmental challenges. TOMRA states: “By combining superior engineering and sensor expertise, AI-powered knowledge processing, TOMRA’s in depth expertise and the strong collaborative relationship with Okay+S, this venture demonstrates the transformative potential of sensor-based underground pre-separation.”
