2000 AND STILL INSTALLED KVAERNER
Location:
EU
Manufacturer:
STILL

Specifications

Condition:
used
Year:
2000
Stock number:
ZW57594
Stock # 2.1.02:
1X BLOW TANK (1,5 M DIAMETER X 13 M), STAINLESS STEEL AISI 316
Stock # 2.1.04:
2X WASH PRESS KVAERNER TYPE 1525
Stock # 2.1.05:
1X STEAM MIXER (SINGLE SHAFT)
Stock # 2.1.06:
1X MC MIXER KVAERNER MXS 30/20-450/760
Stock # 2.1.07:
1X MC PUMP KVAERNER MCP 20/10
Stock # 2.1.08:
1X SCREW CONVEYER
Stock # 2.1.09:
1X SCREW PRESS FOR REJECT HANDLING/DEWATERING
Subcategory 2:
Mills, lines & system

Description

Used and still installed kvaerner oxygen delignifation. New in year 2000. this plant was designed to run at 5 bar operationg pressure on the reactors. The whole plant is designed to handle up to 600 tpd, and in this producer’s process with the actual characteristics of pulp it wasn’t necessary to be above 2 bar operating pressure. Includes:
stock # 2.1.01: 1x reaction tower (up flow), (4 m diameter x 29 m), stainless steel aisi 316
stock # 2.1.02: 1x blow tank (1,5 m diameter x 13 m), stainless steel aisi 316
stock # 2.1.03: 1x washing diffuser kvaerner type 30b (2 m diameter x 16+2 m) stainless steel aisi 316
stock # 2.1.04: 2x wash press kvaerner type 1525
stock # 2.1.05: 1x steam mixer (single shaft)
stock # 2.1.06: 1x mc mixer kvaerner mxs 30/20-450/760
stock # 2.1.07: 1x mc pump kvaerner mcp 20/10
stock # 2.1.08: 1x screw conveyer
stock # 2.1.09: 1x screw press for reject handling/dewatering
stock # 2.1.10: m&c: control system metso damatic, control valves neles, flow meters krohne, consistency btg, ph measurement tbi bailey.
level-pressure-temperature indicators rosemount/wika, wash press drive hagglunds spider control system.
advantages with oxygen delignification:
– additional delignification after cooking at higher selectivity than continued cooking
– reduced emissions from the bleach plant
– reduced consumption of bleaching chemicals
– higher brightness ceiling in a given bleaching sequence
– lower shives content, reduced extractives content, maintained pulp strength
– facilitates system closure
– well-proven technology, suitable for future process changes
oxygen delignification can be regarded partly as a continuation of cooking and partly as the first stage of bleaching. New in 2000. Today it is a standard stage in the production of bleached chemical pulp. Production cost benefits is apparent in both ecf and tcf bleaching. In the oxygen delignification stage the pulp is treated with oxygen in a pressurized vessel at elevated temperature in an alkaline environment. The delignification may vary in the range 40-70% depending on the wood raw material and whether one or two reactors in series are used. Unbleached kraft (sulfate) pulp has a lignin content of 3-5%, which after oxygen delignification can be decreased to about 1.5% or a kappa number of 8-10.
the balance between cooking and oxygen delignification:
from a bleachability, selectivity and yield point of view it is better to extend the oxygen delignification instead of extending the cook.
the cooking kappa should be optimized together with the oxygen delignification.
extend the cook, but not too far – let the oxygen delignification do its job.