This article looks at various ways to increase power generation in pulp mills. The main purpose of the study was to identify and verify the best ways of power generation growth. Calculations of possible main options with different alternatives were presented. The calculations were made by computer program PROSIM. The combination of calculated cases generated was 44 different models of electricity generation from a pulp mill. The various improvements for optimising the power production in a modern greenfield pulp mill can be done by various add on investments with differing pay back periods. Six main power increasing options were studied individually or in combination with each other: increase of black liquor dry solid content, higher main steam parameters, heating of feed water, heating of turbine condensate, heating of combustion air and using flue gas heat recovery techniques to heat air or water.The target of the work was not only to define extra electricity generation from different alternatives but to examine profitability using estimated investment costs of generated options. So for each case an investment profitability was calculated for a greenfield bleached kraft pulp mill with an estimated production of 1 000 000 ADt/a as basis. This represents a typical modern greenfield mill when built today.In addition possible technical, environmental and corrosion risks are presented that can hinder the use of the described alternatives. The main results are presented as simple step by step approach for the use in determining the optimum investment pathway between low investment cost and low electricity generation alternative to high investment cost and high electricity generation.
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