Pulp production is essentially the cooking of wood in a chemical solution in order to remove its connective and adhesive properties. The resulting pulp resembles cotton wool, and can be used as a raw material for making paper and board. In fact the production of pulp is not quite so simple as this. Not when the goal is to create just the right kind of raw material for a specific end-product. This is where profound fibre expertise is crucial.
The type of raw material significantly affects the properties of paper and board. Metsä Fibre uses both softwood (pine, spruce) and hardwood (birch) for pulp production.
Significant production of other bioproducts and bioenergy
Wood is used very efficiently, with part of the raw material extracted as pulp fibre. The rest is used as other bioproducts and bioenergy source for generating heat and electricity. Pulp production activities also generate tall oil and turpentine for the chemical industry's specialty products and biofuels. Our pulp mills generate produce more bioenergy than they use. The excess energy is sold.
Environmental impacts are minimised
Recovery of cooking chemicals takes place in the recovery boiler, where the chemicals are regenerated for re-use by causticising. Gradual enclosure of water cycles and increasing of process-internal cleaning have reduced the volume of effluent, with a consequent reduction in the loading of waterways. Effluent is now treated biologically prior to discharging into waterways. Fuel gases are scrubbed, and malodorous gases originating in the process are recovered and burned.