European industries have realized that a reduction of primary energy usage is not only a European requirement but can also be of great economic interest. Especially both energy and resource intensive industries like the pulp and paper industry will benefit. Industrial excess heat as a by-product of industrial processes needing energy has a great potential to be a key factor in reducing primary energy usage. Both excess heat utilization and heat integration are potential ways for Kraft pulp mills to increase their energy efficiency, to decrease their primary energy use and thus green-house gas emission, and to support the pulp and paper industry to achieve sustainability goals and meet EU regulations. This thesis examines the total excess heat potential in the Swedish Kraft pulp industry through pinch analysis and optimization on a modelled average Swedish Kraft pulp mill (FRAM). Different excess heat recovery technologies (EHRTs) are identified based on their applicability and are evaluated regarding their environmental and economic benefits for the Swedish pulp industry by using the energy price and carbon scenarios tool (ENPAC tool). An excess heat potential in the Swedish Kraft pulp mill industry of 2,03 TWh at 60°C, and 3,53 TWh at 25°C is found in this study. Heat delivery to the district heating network (DH), cooling delivery to the district cooling network (DC), electricity generation with a condensing turbine (CT), phase-change material engine (PCM) and organic Rankine cycle (ORC) are identified as suitable excess heat recovery technologies for Swedish Kraft pulp mills. A payback time calculation in this study found the condensing turbine as the EHRT to be of highest economic benefit in 2018 (less than 3 years). With predicted future energy prices of the years 2030, 2040 and 2050 all considered recovery technologies become economically feasible (payback time of less than 3 years). The CT and combinations of CT with DH and DC are furthermore the recovery technologies with the highest CO2 savings of 100.000 t/a in 2018. All in all, this study suggests investing in a CT, or combinations of it with DH and DC, to create the greatest economic and environmental benefits in 2018. With future price changes on the energy market and an uncertain future energy demand an investment in combinations of recovery technologies generating both heat, cooling and electricity is found to be the most sustainable choice.

The Member States of EU27 need to accelerate the integration of energy efficient technology solutions to reach the 20% energy efficiency target set for 2020. At current pace, projections indicate that only half of expected primary energy reductions will be reached. To meet the energy demands of growing populations and a vibrant economy, while simultaneously reducing primary energy supplies, the European continent faces a new kind of challenge never previously encountered. The identification and application of feasible, competitive, and comprehensive solutions to this problem are of highest priority if the remaining gap is to be closed in time. How is this multi-dimensional and complex dilemma to be dissolved? In this work, expanded use of district heating technology is conceived as a possible solution to substantially reduce future primary energy demands in Europe. By extended recovery and utilisation of vast volumes of currently disregarded excess heat from energy and industry sector fuel transformation processes, district heating systems and combined generation of heat and power can improve the general efficiency of the European energy balance. To investigate the possible range of this solution, this thesis introduces a set of methodologies, theoretical concepts, and model tools, by which a plausible future excess heat utilisation potential, by means of district heat deliveries to residential and service sectors, is estimated. At current conditions and compared to current levels, this potential correspond to a threefold expansion possibility for directly feasible district heating systems in European urban areas and a fourfold increase of European excess heat utilisation.