Production methods

Production methods

High quality ores are becoming rarer. The accelerating demand for base metals challenges the global economy and sustainability. Are there ways to produce more with less?

We have a great asset at our disposal: bioheapleaching – a cleaner production technology. This process uses natural bacteria in the leaching of sulphide minerals.

The Sotkamo deposits are one of the largest known sulphide nickel and zinc deposit in Europe. Our products are streamlined for the raw material flows in battery and stainless steel industries. We want to take an active role in zinc markets, also by developing new product uses. And we will continue on our innovative road for decades to come.


Mining and ore processing

Ore is first mined at the open pit mine, then crushed, agglomerated, transported and stacked to the bioleaching heaps.


Bioheapleaching is a process in which metals are leached from ore as the result of bacterial activity. Bioheapleaching is a very energy-efficient method to produce e.g. nickel. Its greenhouse gas emissions are approximately 40% lower than average, sulphur dioxide emissions only 2% of average and energy consumption 20% lower than average.

The process is carefully controlled so that the metals will leach as efficiently as possible. Leaching heaps are aerated and irrigated with acidic leaching solution. This creates optimal conditions for bacterial activity. Bioheapleaching is an exothermic process which evaporates water and works effectively throughout the year.

The ore is first stacked and leached for approximately 15 months in a primary heap. After this the ore is reclaimed, transferred and stacked to the secondary heaps for final leaching.

Metals production

Metals are extracted from the pregnant leach solution (PLS) and precipitated as sulphides in phases at the metal extraction plant. The final products are filtered and sold for further processing.


The final products are shipped to customers in by train or vessel. High nickel and zinc content in the final products saves logistics costs due to less material to be transported.

Ready for renewal

Ready for renewal

In 2017, we will provide our customers with 80,000 tonnes of nickel, zinc, cobalt and copper contained worldwide. Modern logistics solutions link our operations to global trade with efficient container shipping routes. This reduces the carbon footprint and further decreases needs for working capital in the metals supply chain.  

We believe that the market is ready for renewal. Together, we will create more cost-efficient ways to explore natural resources. We will also discover cleaner ways to fulfil the needs of the modern way of life. We at Terrafame are leading this change – by extracting innovation.