Material Topic: Air Pollution Emissions

305–1  Direct (Scope 1) GHG emissions

Boliden reports this indicator for the units over which it has ­operational control. The direct carbon dioxide emissions arise from GHG emissions from carbonaceous raw materials, from fuels in metal extraction processes and fuels for heating, and from the use of fuels for mining operations and road transportation within the company.

The direct emissions are calculated in accordance with the procedures laid down in the WBCSD1) GHG2) Protocol, together with additional guidelines from the EU and/or national ­authorities.

The CO₂ reporting within the framework of ETS is carried out in accordance with separately audited procedures in each country, and although we seek to report the same data, we cannot guarantee that the Group’s GRI disclosure will correlate exactly to the CO₂ data reported within ETS.

1) World Business Council for Sustainable Development

2) Greenhouse gas

305–2  Energy indirect (Scope 2) GHG emissions

Boliden reports this indicator for the units over which it has operational control and includes only production-related indirect emissions. In 2015, Boliden began using location-based emission factors. This was an adaptation to the updated GHG Protocol Guidelines for Scope 2 reporting. The calculation is made by multi­plying the energy used with the production mix for the spec­ific region. The production mix should be as current as possible, and Boliden uses emission factors published by International ­Energy Agency. For the 2018 reporting, the following emission factors were applied: for the operations in Sweden 10.8 (11.0), Finland, 106.8 (147.2), Norway 9.0 (8.0), and Ireland 417.6 (425.2) g/kWh.

Carbon dioxide emissions, Scope 1+2, tonnes





Direct emissions, (305-1)




Indirect emissions, (305-2)




Total (305-1 + 305-2)




1) The indirect emissions for 2016 have been corrected to 459,000 from 404,000 t due to an incorrect CO2 emission factor in the previous GRI report disclosure.

Carbon dioxide emissions (Scope 1 + Scope 2), 2018 per source

The total reported CO² emissions are 0.971 (1.024) Mtonnes for the year.

Electricity, 31%

Heat, 3%

Oil, 17%

Raw material, 14%

Gas, 2%

Coal and coke, 20%

Diesel and petrol, 12%

Other, 2%

305–4  GHG emission intensity 

Boliden’s GHG intensity was 0.64 (0.69) t/t metal. The GHG intensity is reported as the product emission intensity (metric tonnes of direct [Scope 1] and indirect [Scope 2] emissions per unit of metal product). Boliden only includes CO₂ gas in the GHG intensity.

The new CO₂ intensity target is to reduce emissions by 3% per year measured from 2017. Boliden has measured CO₂ intensity for all units since 2012.

Greenhouse gas emission intensity

Greenhouse gas emission intensity (t CO²/t metal)

305–5  Reduction of GHG emissions

The GRI definitions state that this indicator should reflect reductions of CO₂ emissions identified under 305-1 and 2. The reductions result is estimated from reported energy savings and energy efficiency initiatives reported in 305-2.

Boliden strives to deliver the excess heat from its processes for use in district heating, wherever possible. The heat supplied by Boliden Bergsöe, Boliden Rönnskär, Boliden Kokkola and Boliden Harjavalta in 2018 corresponds to 340,000 (270,000) tonnes/annum of CO₂ (Scope 1) if the same amount of heat had been produced from a fossil-fuel source.

Boliden is also, over and above these measures, actively initiating attempted reductions in fossil-fuel emission by means of fuel substitution tests, participation in demonstrations of electrified road transports, and improved heat recovery/exchange with the aim of phasing out the use of fossil fuels for heating purposes.

Boliden is a co-owner of a production company for wind-based power, VindIn AB, which builds and operates wind farms in Scandinavia. The purpose of VindIn is to take a longer-term approach and to deliver low-cost, renewable electricity. VindIn currently produces about 300 GWh in its three wind farms in Sweden and Finland.

In 2018, Boliden Bergsöe inaugurated the microalgae cultivation for treatment of process emissions. The method used entails using waste heat from the process to grow algae. The project is expected to capture CO₂ emissions, create energy and clean metal emissions from the flue gas.

305–7  Other significant air emissions

Other significant air emissions deriving from Boliden’s operations are nitrogen oxides (NOx), sulfur oxides (SOx), metals, and dust. The most common of the sulfur oxides (SOx/SO₂) is sulfur dioxide, and Boliden generally uses the expression ‘sulfur dioxide’ to describe this emission. The figures for sulfur dioxide and NOx disclosed in the table are the direct measured emissions from sources at Boliden’s smelters. The figures for metals and dust include the direct-measured emissions from smelter stacks, but exclude diffuse emissions.

Diffuse emissions are generated at both mines and smelters and the environmental impact is due to dust particles containing metals being dispersed by the wind. All operations are working systematically to reduce particle emissions to air, e.g. by enclosure of dust-generating equipment and by salting and watering roads. The diffuse emissions are monitored, but are difficult to quantify in an aggregated manner.

Emission Reduction Efforts

Boliden’s efforts to reduce emissions are based on an overall analysis of the environmental impact. The impact and risk ­assessments are revised on a regular basis, as are the measures to be taken. The work is controlled and conducted by each individual business unit, as local circumstances may differ. Follow-up at the Group level is conducted on a monthly basis.

Sulfur dioxide emissions to air are mainly attributable to gases generated during the smelting processes at the Harjavalta and Rönnskär copper smelters. The amount of sulfur dioxide emitted during the process depends on factors such as process stability, the efficiency of the gas cleaning systems, and the amount of sulfur in the raw materials. One way of reducing emissions is, accordingly, to maintain a stable smelting process and to have continuous and effective maintenance work and control of the process. The monitoring and control of abatement systems for effective gas cleaning is important work and is carried out continuously.

The SO₂ emissions to air increased slightly in 2018 due to increased emissions at all Boliden Smelters in Q2. All leakages were effects of changes in the processes, which caused unexpected leakages. In Harjavalta there were problems in a converter, which were solved during maintenance work in June. In Kokkola there were leakages in the heat exchanger which were resolved in May. A new reduction agent grade was used at Rönnskär, resulting in higher SO₂ emissions. Several leakages in Rönnskär’s converter hall were also identified and are currently still ongoing. They are, however, scheduled for correction during 2019.

The ongoing work focuses on process stability and the improvement and/or replacement of technology. Emissions to air are mainly based on periodic monitoring in accordance with applicable national standards. Emissions from fuel are calculated using the fuel properties data provided by the supplier. Accredited laboratories, both internal and external, are used for the analyses of samples taken on site.

Emissions to air (tonnes)













Particulate matter




Metal emissions to air (me-eq)




Metal emissions to air (mass)