Friday, 14 February 2020 11:08

New fertiliser deposits closer to home

Written by  Mark Daniel
Australia’s Lake Mackay is said to cover anarea of 3500 square kilometres – making it the largest, undeveloped sulphate of potash bearing sale lake in the world. Australia’s Lake Mackay is said to cover anarea of 3500 square kilometres – making it the largest, undeveloped sulphate of potash bearing sale lake in the world.

The topic of shipping fertiliser around the world, brings with it environmental and socio-economic issues — but that may soon change.

To see the issues, just look at what is currently facing Ravensdown regarding the sourcing of phosphate from the Western Sahara.

In the case of Potash, the main producers are Canada, Russia and Belorussia, which cumulatively account for two thirds of the world’s production. 

However, in the future, it looks likely that those figures might change. New Zealand will likely source its supply of K from closer to home – when production from Australia comes on stream.

Lake Mackay, in the big country’s Northern Territory and Western Australia areas, is said to cover an area of 3,500 square kilometres – making it the largest, undeveloped sulphate of potash bearing salt lake in the world.

Experts suggest that once developed, Lake Mackay will allow Australia to move from a position that sees it import 100% of its potash requirements, to one of the most globally significant producers and exporters.

Lake Mackay’s brine-hosted potash deposits are different from hard rock deposits, in that the groundwater may be recharged over time, where rock-based residues are eventually mined out. Ninety per cent of all potash production in the world is Muriate of Potash (MOP), which contains 46% chloride.

Lake Mackay’s Sulphate of Potash (SOP) and Sulphate of Potash Magnesia (SOPM) are premium chloride-free forms of potash fertilizer, which is increasingly being used for advanced farming practices to minimize agricultural pollution and water usage.

During production, the extraction of potassium-rich brine is achieved via a shallow trench system. As one might expect of such a vast area, the trenches and feed channels will have a length of 550km, an average depth of 4.5 metres and result in 8.5 million cubic metres of material being excavated.

Brine will flow along the trenches and feed into solar evaporation ponds the will eventually cover 34 square kilometres at start up. 

As one would expect in such a remote location, the excavation of these trenches and canals – plus the establishment of the evaporation ponds – is no simple task. The upper crust of the lake is only 50cms thick, with a semi-fluid layer beneath. These physical properties require the use of amphibious excavators, designed and manufactured in Finland, while also dealing with the intense heat of WA – in an environment that is ten times saltier than seawater.

A feasibility study completed in 2018, estimates that Lake Mackay’s SOP production rate will be around 426,000 tonnes during the first 20 years. This is double Australia’s current annual consumption. 

More like this

No-frills fert on offer

Ballance Agri-Nutrients has launched SimplyFert, an ex-hub and therefore lower-cost offering said to give its shareholders choice and flexibility for purchasing nutrients.

Fert prices drop

Both major fertiliser co-operatives have dropped their prices as farmers start planning for spring.

A significant fertiliser breakthrough?

Former ACT MP and Federated Farmers president Owen Jennings believes he's come across a new fertilising method in Australia that yields "outstanding results".

Featured

New Image turns 40!

Auckland manufacturer and distributor of colostrum-based supplements, New Image International, celebrated its 40th anniversary this month.

National

Winter grazing warning

Every time people from overseas see photographs of cows up to their hocks in mud it's bad for New Zealand.

ANZ defends farm lending rates

The country's largest lender to the agriculture sector says it's not favouring home loans over farm and business lending.

Machinery & Products

Expo set to wow again

Stellar speakers, top-notch trade sites, innovation, technology and connections are all on offer at the 2025 East Coast Farming Expo…

A year of global challenges

As a guest of the Italian Trade Association, Rural News Group Machinery Editor Mark Daniel took the opportunity to make…

» Latest Print Issues Online

The Hound

Review SOEs!

OPINION: NIWA has long weathered complaints about alleged stifling of competition in forecasting, and more recently, claims of lack of…

Bank reset

OPINION: Adding to calls to get banks to 'back off', NZ Agri Brokers director Andrew Laming has revealed that the…

» Connect with Rural News

» eNewsletter

Subscribe to our weekly newsletter