A practical approach to research and development
Terrafame focused on its research and development work during the year to assist its production organisation. In addition to the daily work, broader research projects were also continued.
In 2016, Terrafame continued its nickel-cobalt and zinc production ramp-up programme, and the main task of research and development was to support production. In practice, the work was done in close cooperation with the various stages of production.
Terrafame's production is based on bioleaching, which is utilised in the extraction of metals from ore. Production technology based on microbial activity has been in industrial use round the world. Terrafame, in turn, has systematically developed its unique expertise in pyrrhotite-concentrated bioleaching of ores under northern conditions.
Support for the different stages of production
At the outset of the production process, in mining, mineralogical surveys were carried out in 2016. Based on this work, it will be possible in the future to plan and control the ore output value of metals and mineral compositions more precisely.
During the ore processing, the research and development aimed at defining the measures for agglomeration and improving the quality of the agglomerate. The homogeneity and permeability of the agglomerates are important factors in the bioleaching stage of the production process.
In the bioleaching, the focus was in securing the consistent process conditions as well as in optimising the microbial activity. During the year, the possibilities to measure the internal electrochemistry and temperature of heaps were also studied. The research and development department also designed and built a leaching colony unit to be prepared for new types of bioleaching studies.
At the metals production plant, the production ramp-up phase was supported by research and development work. Running parameters were optimised so that the start-up of the plant after shutdowns is as smooth as possible. At the same time, development work was carried out on the ramp-up phase of the plant in order to eliminate the odour of hydrogen sulphide gas emissions.
Pre-study on further nickel processing brings encouraging results
Terrafame's main product during the entire period of its operations has been nickel-cobalt sulphide (NiCoS). However, the company's goal is to find ways to increase the value of its products. One possibility is to further process NiCos into nickel oxide. In this form, nickel could be sold in further processed form directly to steel works.
In 2016, Terrafame performed a pre-feasibility study on further processing nickel. The results were encouraging. In addition, further processing of the company's nickel was tested successfully by a third party in a full-scale test run.
In practice, nickel oxide production requires the addition of a roaster in Terrafame's production process after the metals precipitation phases. Roasting the by-product of the sulphur dioxide produced can, in turn, produce sulphuric acid suitable for leaching the metals. Nickel oxide production was also introduced in November in the EIA programme covering the company's mining operations.
Landscaping requires research
The closure of mining areas in Finland is controlled by legislation and permit decisions. Terrafame’s operations are set to continue for decades, but during the past year, the company carried out research and development work on covering gypsum ponds and secondary leaching areas as well as in connection with landscaping.
Terrafame's environmental monitoring is carried out by an independent third party. In addition, the company takes its own samples, by which it monitors the mining area on a daily basis. During 2016, the research and development laboratory was also utilised in the analysis of these environmental samples.
In 2016, Terrafame also conducted research cooperation with external research institutes and universities, mainly in Finland.
Water management research further developed
In the autumn of 2015, Terrafame's parent company Terrafame Group Ltd. launched a development project to support the environmental work at Terrafame mine. In the spring of 2016, the cooperation project progressed from conceptualisation to trial activity stage, and in November four process water management pilots were launched in the mining area. With the pilot projects, possibilities are being sought to further reduce the environmental impacts of the mine, improve production efficiency, and create new business opportunities.
During the year, Terrafame Group Ltdt applied for a patent for a new overall concept on water management, as well as for a collection of individual inventions. In addition, the operators involved in the development project filed their own patent applications related to their specific technologies.
In bioleaching, microbes are utilised to catalyse iron and sulphur chemical reactions.