The DNI Process™ is Enabling Technology:
A low cost, efficient and environmentally sympathetic route to the production of nickel, cobalt and transitional products for the EV battery and stainless steel markets
patented, unique, game changing
THE DNi PROCESS™
- The DNi Process™ has been developed to produce nickel metal, oxides or hydroxides and cobalt together with other products.
- The DNi Process™ is based on elegantly simple chemistry: with continuous, rapid tank leaching, achieving high metal recovery rates, particularly of nickel and cobalt but also of iron as hematite and magnesium oxide.
- The DNi Process™ is most efficient at extracting nickel and cobalt from laterites and is the first process to treat the entire profile of a laterite deposit – limonite and saprolite – meaning much better economic use of the resource, effectively doubling resource utilisation.
- A key feature of the DNi Process™ is that over 95% of the leach reagent, nitric acid, is recovered and recycled, lowering production costs and efficiently reducing associated environmental issues.
- Plant Capex is lower than other hydrometalurgical processes in part because the DNi Process™ does not require high pressures or high temperatures, or exotic materials of construction. Also, the minimum threshold plant size is around 5,000 tpa nickel output, significantly smaller than the entry-level plant which competing technologies must build.
- A DNi Process™ plant can be constructed utilising commercially available off-the-shelf equipment and well-proven stainless steel fabrication techniques. Plant construction can be modular, further de-risking scale-up costs.
THE DNi PROCESS™ – ENABLING TECHNOLOGY
- DNi’s technical partners include Drinkard Metalox Inc. and the CSIRO, both of which have considerable experience in mining and minerals processing and recognise the distinct advantages of the DNi Process™ when compared to existing technologies.
- The DNi Process™ has been significantly de-risked with the assistance of these partners and through rigorous testing of the reagent recycle process at the pilot plant in Perth, Western Australia.
- The DNi Process™ is environmentally friendly because almost all the reagent is captured and recycled. The mass of waste residues is less than half that of HPAL processes principally due to minimal loss of the reagent and the addition of fewer neutralising agents. Also, nitrates in processed residue break down to usable nitrogen for plant growth. This may prove to be a major advantage in nitrogen deficient high-rainfall tropical environments and a boost to local agriculture.
- The economics of the DNi Process™ includes the production of saleable co-products, significantly increasing project revenue.
The DNi Process™ is:
- A unique opportunity because the only commercially available, internationally implemented, process which can match DNi’s flexibility in output is High Pressure Acid Leaching (HPAL) – unlike HPAL, the DNi Process™ is capable of treating the entire saprolite profile whereas the more saprolite added to the HPAL process renders it less profitable.
- Able to treat just limonite ore (provided 3-4% (by weight) magnesium is added to the feed).
- Can easily adapt to changing market demands with the simple addition of different refining units on the back end of the processing plant. The principal markets for DNi’s output, currently, are:
- The Stainless Steel market: Nickel metal, Cobalt metal or Cobalt oxide;
- The Rechargeable Battery market: NiCO3 and other Ni/Co products.
NICKEL USES – TODAY AND TOMORROW
- Nickel is widely used in over 300,000 products for consumer, industrial, military, transport, aerospace, marine and architectural applications.
- The biggest use of nickel is in alloying – there are approximately 3,000 nickel-containing alloys – about 90% of all new nickel sold goes into alloys with about two-thirds going into stainless steel.
- Current uses for nickel-containing materials include: electronics, specialist engineering, coinage, marine engineering, food preparation equipment, mobile phones, medical equipment, hybrid cars, buildings and power generation. They are selected because they offer better corrosion resistance, better toughness, better strength at high and low temperatures and have a range of special magnetic and electronic properties. In many of these applications there is no substitute for nickel without reducing performance or increasing cost.
- Stainless steel represents the single largest use of nickel and typically contains 8-12% nickel. Some nickel-based alloys with higher nickel contents are used for more demanding applications such as gas turbines and some chemical plants.
- Nickel is a key element in several rechargeable battery systems.
- Developing uses for nickel include:
- nanoparticle nickel – utilised in 3D printing of sensors with a high spatial resolution, such sensors will be embedded within the layers of printed circuit boards opening up a world of possibilities for the monitoring of various energies and their derivatives such as capacitance, magnetism, temperature and radiation; and
- the production of faster, purer and cheaper graphene.
- Nickel use is growing at around 4% each year.
TECHNOLOGY DEVELOPMENT & TESTING
The 1 tonne/day DNi Pilot Plant at CSIRO’s research centre in Perth, Western Australia has proven that the DNi Process™ is simple and safe to operate on a continuous basis, with metal recoveries and reagent recycling meeting and, in many cases, exceeding expectations.
The DNi Process™ is protected by registered patents.
This graph illustrates the leaching times for various hydrometallurgical nickel laterite processes. The data is all taken from publically available sources, and demonstrates the residence time differences between currently operating technologies and new processes in development. As can be seen, most of the technologies that utilise strong mineral acids (nitric, sulphuric, hydrochloric) in an agitated tank configuration all show reasonably similar leach residence times, although HPAL benefits from a shorter tail due to the higher pressure and temperature and PosNEP benefits from an ore pre-treatment (the time of which is not included here). Weaker acids obviously require longer leaching times, as do less ideal configurations like heap leaching.