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Thermal-Mechanical Pulp (TMP) Plant .jpg)
In the TMP plant the wood chips are beaten to wood pulp under 4 MPa pressure in disk refiners.
The original CTMP (chemi-thermo-mechanical pulp) plant was put into operation by SUNDS DEFIBRATOR in 1989 with a capacity 200,000 ton/year. In 1997 the plant was reconstructed and converted to wholly TMP by FMW.
The TMP plant has four production lines.
The wood chips are transported from the wood yard into 750 m3 chips storage bins and subsequently beaten in two stages in RGP-60S refiners (electric motor power 8.5 ÌW for the first stage and 7.5 ÌW for the second). The refined pulp is screened in D8 pressure separators with 0.25 mm slots.
The screened pulp is thickened on ENSO disk filters and bleached with sodium bisulphite in bleaching towers (320 m3) up to 62-65% brightness.
Screen rejects are sent for refining to RGP-60S refiners (electric motor power 7.5 ÌW).
The refined, screened and bleached TMP is fed to the paper machines.
Purchased chemical pulp treatment
Following closure of the sulphite pulp mill for environmental reasons, the plant for processing purchased market pulp was put into operation in 1997.
Bleached sulphate pulp, packed in bales, is delivered to JSC Volga by rail. The bales are dissolved in hydro-pulpers GRVm-16 (capacity 160 ton/day) and GRV-02 (40 ton/day). After refining in Andritz Twin-Flow refiners the pulp can be fed to the paper machines.
Stone Ground Wood (SGW) mill .jpg)
The SGW mill produces white mechanical wood pulp by abrasion of debarked logs against ceramic rotating stones in the grinders. The stone ground wood mill, with a capacity 400,000 ton/year, was put into operation in 1965 and thermo-grinding was added in 2000.
Spruce pulpwood in 1.2 m long pieces comes from the wood yard on a conveyor system and is loaded into the grinders. Grinding is done on DC-04 chain grinders (manufactured in Petrozavodsk, capacity 45 ton/day, electric motor power 3.2 ÌW, 300 rpm).
The mechanical wood pulp is screened and cleaned on vibration chip collectors, centrifugal screens and traps. The screened and cleaned mechanical wood pulp is thickened on the multi-disk Fampa filters and bleached as required by sodium bisulphite up to 61-62% brightness and fed through storage tanks to the paper machines. |
