CO2 is part of the equation
Silicon is extracted from quartz, which consists of silicon and oxygen, in a high temperature chemical process where carbon material is needed to separate the oxygen from the silicon. The oxygen binds to the carbon and forms CO2, and silicon can be tapped from the smelter. With current technology it is not possible to avoid the forming of CO2 in the reduction process.
Elkem has participated in the EU emissions trading scheme since 2013 and supports schemes that are designed to ensure that the most cost efficient emissions mitigation measures are taken first.
Elkem believes that we can produce silicon without net carbon emissions. You can read more about our carbon neutral metal production project here.
The high temperature smelting process used to produce silicon causes also the formation of nitrogen oxides (NOx). Nitrogen oxides are exhaust gases that cause acid rain and increased concentrations of ground-level ozone. These emissions can be harmful to ecosystems and vegetation. In cities, where transportation (vehicle exhaust) accounts for the vast majority of NOx emissions, it can also present a risk to public health.
Through dedicated research, Elkem has managed to form a good understanding of why and how NOx is created in the smelting furnace. This has allowed us to develop new technology to reduce emissions that is being implemented in our plants.
The high temperatures in our smelting process are achieved using electrodes to create high energy electrical arcing. Elkem is one of the world’s major producer of electrode material through the Carbon division. Critical raw materials in electrode production include coal tar pitch which contains PAH components that are defined as harmful to living organisms.
Because of this, Elkem works systematically to control all emissions of PAH from its processes and has taken a leading role in the development of alternative raw materials for the process (so-called green binders).
Systematic dust reduction
Dust represents a health hazard for our workers in addition to being a pollutant. Dust also means waste because dust particles are unavailable raw materials or products that have gone astray. It is also detrimental to equipment and creates extra work in collection and cleaning. The fight against dust, both internally in our production facilities and externally through emissions control is therefore a top priority for Elkem.
Read more about our work to abate emissions in the Sustainability report.