Abstract

Objectives

The main objective of the project is to increase the production of green electricity from the spent liquors of a new wood pulping process as an integral part of the fibre manufacture. This target is to be achieved by the adaptation of a new sulphur-free pulping process, which produces spent pulping liquors that are easier to gasify or fire in high pressure recovery boilers than the sulphur containing traditional kraft pulping black liquors.

With traditional kraft pulp processing of chips to papermaking fibres the problem is the low amount of excess electrical energy obtained during the recovery of the cooking chemicals. If the spent pulping liquor could be gasified (or combusted in a high efficiency steam boiler), the excess amount of electricity would be about 1500 kWh per ton of the pulp produced (or 900 kWh per ton of pulp in the case of high efficiency recovery boiler). This is 3 to 5 times more than the excess electricity obtained in today's modern pulp mills. It is important to observe that this electricity is green, i.e. it is produced from renewable bio-resources.

Description of work:

The project is divided into three phases:

• Pulping and bleaching studies of selected hardwood species;
• Laboratory-scale studies on energy production (andon recovery of cooking chemicals) from the spent liquors of the new sulphur-free pulping process, and;
• Feasibility study of energy production and of cooking chemicals recovery using data from phase 2.

The traditional kraft pulping process is used as a bench marking reference for the above feasibility studies.

Expected Results and Exploitation Plans:

The main results of this project can exploited to justify large-scale piloting of these new power generation processes in conjunction with the recovery of pulping chemicals. The results of this project do not yet warrant a direct expansion to a full-scale commercial process. The socio-economic significance of the eventual commercial scale green power production as an integral part of the pulp production is that European pulp industry could easily produce 3000 MW green electricity, i.e. about 1% of EU's overall peak electricity demand. For countries having a significant pulp and paper industry, the results of this project could mean that an additional 10% of the national electricity consumption could be supplied by this green electricity method. In addition, the new technology that will be developed could be exported to important areas of pulp production, i.e. to North America, South America, and South-East Asia thus providing markets and jobs for the European equipment suppliers.

Contacts

Coordinator

• Kari EBELING / UPM Kymmene Corporation FINLAND

Participant

• Erkki KIISKILAE / Andritz Ahlstrom Corporation R & D Department / FINLAND
• Centre Technique De L'industrie Des Papiers, Cartons Et Cell Environmental Division / FRANCE
• RAIZ Instituto de Investigacao da Floresta e Papel PORTUGAL
• Dieter WEBER / Siemens AG MS 2 CT Corporate Technology / GERMANY