Peak phosphorus in sight: more effective use will extend world availability

Estimates vary as to how much high quality and lower grade rock there is in the few countries known to have reserves – dominated by China, the US, and Morocco – and how much current and emerging technologies could increase phosphate stocks from low grade rocks. However, phosphorus researcher Dana Cordell, of Sydney’s Institute for Sustainable Futures and the Department of Water and Environmental Studies, Linköping University, Sweden, says that despite increasing global demand for phosphate rock and its critical role in food production, “global phosphate scarcity is missing from the dominant debates on global food security.

“Phosphorus scarcity has not received explicit mention within the Food & Agricultural Organisation of the UN, the International Food Policy Research Institute , the Global Environmental Change & Food System Programme or the recent FAO High Level Conference on World Food Security. The implications of declining global phosphate availability and accessibility are mentioned in very few discussions by few concerned scientists.”

Because of increasing global demand for fertilisers, the loss of high grade phosphate rock will have severe impacts on Australian agriculture, unless farmers adapt quickly to new ways of growing crops, using less phosphate-based fertiliser, reducing phosphorus loss between fertiliser application and harvesting, or replacing commercial fertiliser with other alternatives such as biosolids or recycled urine.

Cordell has considered the implications for Australia of a global fertiliser scarcity. With the Institute’s Director, Professor Stuart White, she prepared a discussion paper. Peak Phosphorus: the Sequel to Peak Oil for the National Workshop on the Future of Phosphorus in November 2008. The workshop was attended by representatives of DAFF, CSIRO, The Organic Federation of Australia, Zero Waste Australia, and the Australian Western Saharan Association.

With Dr White and Dr Jan-Olof Drangert from the Department of Water and Environmental Studies, Linköping University, she, has also written a paper, The story of Phosphorus: global food security and food for thought, about to be published in the journal, Global Environmental Change.


Phosphorus researcher Dana Cordell

Australian farmers are likely to be hit harder by the scarcity of phosphate rock in the next 100 years because of the natural deficiency of phosphorus in our soils, leading to greater dependency on phosphate fertiliser. Cordell says the problem is exacerbated by the fact that our agriculture is based on some of the most phosphorus-intensive export industries – wheat, beef and wool, leading to a net deficit of phosphorus in food production and consumption. About 80 per cent of the phosphorus in Australian-grown food and fibre is exported.

Phosphate rock contains around 24-30 per cent of P205 (phosphate), and P2O5 has exactly 44 per cent phosphorus. Australia has some phosphate reserves at Phosphate Hill in Queensland, which in 2006 produced 2.083 million tonnes of rock, equivalent to 220 kilotonnes (kT) of phosphorus, but most phosphorus is imported, either as raw phosphate rock or as readymade fertilisers. Between them, Australia’s three fertiliser manufacturers – Incitec Pivot (IPL), CSBP and Impact – import phosphate rock per year, plus 223 kT of readymade fertiliser, derived from 0.655 million tonnes of phosphate rock.

IPL uses 2.7 million tonnes per annum – 2.2 million from their own phosphate mine at Phosphate Hill to manufacture ammonium phosphate fertilisers, and 0.5 million from various countries, including Morocco, Christmas Island, Nauru, Vietnam, Togo, China and South Africa to manufacture single superphosphate (SSP) and other fertilisers. IPL also imports phosphorus-based fertilisers from the US, Germany, China, Mexico and Israel.

CSBP imports approximately 120 kT per year of phosphate to manufacture single superphosphate fertiliser at its Kwinana operation in Western Australia.

While the company was not prepared to give a further breakdown of figures, CSBP Managing Director Ian Hansen said it sources phosphate rock from Western Sahara, China and Australia, and finished phosphate fertilisers from China and the US. Comparable figures were not available from Tasmanian company Impact Fertilisers.

China has the most phosphate rock, with reserves of 6,500 million tonnes, but imports from China are relatively expensive. In 2008, fertiliser manufacturers and farmers alike were shocked at the hike in price of phosphate rock from China, thanks to tariffs of 175 per cent. ANZ Analyst Paul Deane explained that China’s involvement in world trade for fertiliser has been an important factor in increasing the volatility of fertiliser prices in recent years. Australian prices are ultimately linked to the world price, so China’s trade policy decisions can have a big impact on Australian prices.

“In 2007 it not only became self-sufficient in its phosphate requirements, but actually became a significant exporter of DAP, MAP and TSP in that year.

“By August 2008 the Chinese Government had imposed an export duty of 175 per cent on DAP, MAP and urea to restrain exports and reduce domestic prices for Chinese farmers. This policy adjustment sent a shudder through the global fertiliser market and was a contributing factor to global fertiliser prices jumping so sharply.

However after staying away from exporting fertiliser for nearly a year by pricing itself out of the global market, the Chinese government has done a back-flip, announcing a cut in the export tariff.”

CSBP has reduced phosphate rock imports from China in response to increased tariffs, even after the cutback, but IPL’s Communications Adviser Neville Heydon says the tariff’s are unlike to affect IPL’s imports from China.

The Morocco/Western Sahara region, the area with the second biggest reserves – around 5700 million tonnes – is the dominant player in the global trade of rock phosphate, accounting for around half the global trade, according to Deane. It is a significant supplier to both Australia directly but also to the US (therefore important in DAP/MAP market there also).

However, this area is “geopolitically sensitive” says Cordell, as Morocco currently occupies Western Sahara, contrary to international law” (ie invasion).

Trading with Morocco for phosphate rock has been condemned by the UN.

Cordell warns that as high quality rock reserves run out, mining of lower quality rock will occur. This has a plethora of environmental and human health side-effects from greater amounts of cadmium, uranium and thorium found with the phosphorus, and greater production of the highly radioactive waste product, phosphogypsum, as well as the higher energy use needed to extract the phosphorus.

IPL is sourcing new reserves of high quality rock and is already using low-grade rock from Phosphate Hill in the production of ammonium phosphate fertilisers. According to Neville Heydon, “current reserves are estimated to provide 30 years of operation and additional exploration and development work could expand the reserves substantially to over 1,000 million tonnes.”

CSBP has invested “a significant amount of cost and resource” to investigate technological modifications to its production process to use raw phosphate rock “from sources which are currently unsuitable for technical or environmental reasons”, says Managing Director Ian Hansen.

New player on the block, Western Australian company, Advanced Nutrients, produces a range of organic fertilisers using second-grade phosphate rock. Using only about 160,000 tonnes of phosphate a year, which the company “spot buys” when the price is right from China, Jordan and Egypt, the company is not concerned about the prospect of peak phosphorus, according to CEO Gary Murdoch-Brown.

He disputes Cordell’s statistics on the size of global reserves, saying they are “dramatically underestimated”, and that North Africa alone has sufficient reserves of all grades of rock for the next 80-150 years.

“Yes, all mined ore will eventually run out, but it’s a matter of developing the technology to safely and economically process the lower grade rock, and that won’t be needed for the next 80-100 years,” he said.

© Sue Cartledge

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