Metso Paper's 1000th TwinRoll wash press now in operation

Published Jan 31, 2006 12.00.00 +2 GMT

AssiDomän Cartonboard's Frövi Mill, Sweden, has successfully started up the one thousandth TwinRoll wash press manufactured by Metso Paper. The Frövi Mill produces high-quality liquid packaging board and general packaging board mainly for food deliveries. The press type TRPW-940 represents the latest generation of TwinRoll presses and was installed after the bleached stock storage tower to dewater bleached hardwood pulp in the board mill. The new press enables the circulation of liquor back to the pulp mill and guarantees high cleanliness of the pulp for board making.

Metso Paper has been manufacturing TwinRoll presses since 1954, when the first MPC and VPC press types were introduced. Today, TwinRoll presses are used in all process stages where efficient pulp dewatering and washing are required. The first installation in a chemical pulp bleaching line took place at the Advance Agro mill in Thailand in the mid-1990s. The latest generation of TwinRoll presses feature increased capacity and washing efficiency. The biggest press types are designed for up to capacities of approximately 3500 tonnes daily. This enables building of a single fiber line for the modern mega-mills.

AssiDomän Cartonboard and Metso Paper have long been in cooperation to upgrade the pulping system at Frövi into an environmentally sound system. Part of this upgrade work is the SuperBatch cooking system, which is the first of its kind in Sweden. The plant was started up in 2002 and is designed for an annual capacity of approximately 175 000 tonnes of hardwood, or softwood pulp. Metso Paper's delivery was an EPC package which only excluded civil works and a DCS system.

In addition, Metso Paper has modernized the brown stock screening system utilizing DeltaCombi technology and enhanced washing in the bleaching line. A new TwinRoll press was installed for the final PO-stage in 2003. The press replaced the earlier DD washer, which was moved to operate in parallel with the existing O2-stage washer. This investment has secured a high and uniform pulp consistency for bleached pulp storage.

Metso is a global engineering and technology corporation with 2004 net sales of approximately EUR 4 billion. Its 22 000 employees in more than 50 countries serve customers in the pulp and paper industry, rock and minerals processing, the energy industry and selected other industries.

For further information, please contact: Lars Sjödin, Vice President, Chemical Pulping, Sundsvall, Sweden Tel. +46 60 16 51 85,

Alpo Tuomi, Marketing Manager, Chemical Pulping Tel. +358 20 482 9813,