Conference article

In Northern Europe there are many CHP plants operating with biomass and waste as fuel. As more wind and solar power is introduced the operating hours of these plants is reduced and thereby also the capital burden is distributed on fewer annual hours. At the same time there is a strong request to replace fossil oil by renewable alternatives for many different purposes. Here biomass and waste are the major resources available to produce liquid or gaseous bio-based products at existing CHP plants. In this study we have simulated system solutions to identify energy and material balances as well as rough economic figures. The products assumed are primarily fuels like diesel, hydrogen and methane, but also other organic compounds can be considered. Today PREEM and St1 are planning large scale production of primarily biodiesel, or HVO, where liquid products from both pulp and paper industry and CHP plants will be suitable feedstock. The study includes a comparison between hydrogen production in gasifiers to electrolysis, and even a combination of these as oxygen from the electrolyser can be used for the gasification, to avoid ballast of nitrogen in the product gas. The study aims to identify optimal solution under different conditions with respect to both electricity and raw material costs, as well as capital cost and operating hours.

CHP, pyrolysis, gasification, HVO, liquid bio-fuel, hydrogen