Agro Mining

Agro Mining

Agro mining involves growing selected hyper accumulator plant species (metal crops) on low grade ore bodies or mineralised (ultramafic) soils or anthropogenic metal rich materials (e.g. contaminated soil, mine soils, industrial sludges), prior to biomass harvesting and incineration to recover valuable metals or salts.

It was in 2000 that a group of scientists developed a method for extracting nickel from the crop of a plant from a fern family, Alyssum murale, which has been growing on nickel-rich soils in Albania. The first step of the extraction process consists in burning the crop which produces energy and nickel-rich ashes. These ashes then undergo multiple chemical treatments to extract nickel salts, which are used for industrial purposes. The concept of agro mining encompasses the complete agro system – soil, ore, plants which conditions the storing of minerals in the plant and the equally important metal extraction system. This concept was registered at the French National Institute of Industrial Property (INPI) in 2007 by Jean Louis Morel. Through this process it is possible to extract up to 100kg of nickel per hectare of Alyssum murale crops. It is a production chain under development, potentially applicable to different metals.

Agriculture on ultramafic soils has often a low productivity due to lack of Calcium, Potassium and Phosphorous and excess Magnesium and Nickel. Over time, agro mining here can improve fertility and significantly decrease Nickel availability.This can be regarded as a significant ecosystem service. Knowledge of suitable ‘metal crop’ species is essential for selecting areas to establish agro mining operations.

Despite scientific validation over last two decades, commercial application of this technology has still not started. This technology needs to be encouraged further to improve mine site rehabilitation while providing opportunities for sustainable post mining livelihoods. Also, as a part of improving degraded land to make if suitable for other uses, agro mining can be applied.

UDAAN’s objective, initially, is to work on the soil polluted by the excessive use of chemical fertilisers and to neutralise the negative impact of the chemicals pollution the soil. This can help in regeneration of soil degraded by extensive use of chemical fertilisers.