PAPER RECYCLING PLANTS - AR Thomson Group

RREECCYCCLLEED PPAAPPEERR
AESSEAL®
PAPER RECYCLING
PLANTS
L-UK/US-RECYCLE-03
IN 4540 - 02/2002
20
© Copyright 2002 AESSEAL plc All Rights Reserved.
By Vendor By Purchaser
API PLAN NO.32
Flush injected from an
External Source.
The water source for Plan 32 should be as clean as possible, however recycled filtered
process water is often successfully used for this purpose.
Pulp plants are extremely resistant to increasing their process water consumption, therefore
towns/utility water supply is rarely a viable alternative. Even recycled water is important to the
user and the flush flow is often controlled using variable orifice flow meters.
Using quench water alone on ENCLOSED boxes is not a solution to the problem of blocking
on the product side. The seal faces will probably not "burn" out but severe erosion of the
rotary will take place.
OPEN STUFFING BOX DESIGN
VORTEX BREAKER
EROSION POSSIBLE
The seals face a different problem with open boxes i.e. if not correctly designed, severe
erosion can take place at the gland. Clogging is no longer an issue but it is often prudent on
higher pulp concentrations (>2%) to use a quenched seal, thereby preventing the blockage of
the internal/spring cavities of the seal (atmospheric side), which would eventually lead to
seizure of the seal rotary causing severe leakage of product.