One of the greatest advantages of integrating a pulp mill with paper and board machines at the same site is energy efficiency. Imatra Mills are over 90% self-sufficient as regards thermal energy due to the use of black liquor by-product from pulping and bark from wood processed at the mills as fuel. Natural gas is the only fossil fuel and the only purchased fuel used at the mills, accounting for less than 10% of heat production.

Enhanced energy production

The major investment in pulping completed in 2001 has significantly decreased carbon dioxide emissions from fossil fuels because the increase in pulp production has increased production of by-product black liquor and bark that are used as fuel instead.

This is one major advantage of a mill site that integrates pulping with paper and board production: most of the electricity consumed by the paper and boards machines is generated by burning by-products of pulp production.

Electricity

The mills generate about 60% of the electricity they consume and the rest is purchased. The high degree of self-sufficiency is important in keeping costs down.

Continuous energy improvements

Stora Enso is looking beyond the major savings from increased energy efficiency at Imatra Mills achieved in the past three years. The mills have signed an industrial energy-saving agreement that commits them to continuous improvement in energy efficiency. No major investments have been required in the past couple of years, but minor improvements are being made all the time. This will have important environmental and economic benefits.