Technical Bulletin No. 10 pages

Meeting Cluster Rule Bleach PlantRequirements Using the RotaBed

Fluidized Bed Scrubber

Introduction

The USEPA recentlypromulgated a new set of
regulations for the Pulp and
Paper industry.Called the
ٓCluster Rule, the EPA sought
to combine both air and water
regulations into one all-
encompassing regulation.This
action has caused engineers
and scientists in the paper
industry to examine plant
operations in light of meeting
these requirements.Of
particular interest are those
aspects of the ԓCluster Rule
pertaining to air pollution
control from the bleach plant.With proper design andapplication, ԓCluster Rule
requirements can easily and economically be met on modern kraft bleaching
sequences using RotaBed Process modifications away
from elemental chlorine can
serve to reduce such
pollutants.High efficiency gas
scrubbers are presently used
on kraft bleach plants to
control the residual gaseous
Cl >
2 and ClO >
2 .Mills abandon-ing elemental chlorine and
substituting chlorine dioxide in
bleaching sequences become
ECF or ԓElemental Chlorine
Free.Other mills that have
switched to a nonchloride
containing bleach sequence
are called TCF mills or ԓTotally
Chlorine Free.A summary of
ԓCluster Rulerequirements
was published in TAPPI,
volume 81, No.2, by Kirsten
Vice and Robert Carrol in an
article entitled ԓThe Cluster
Rule:A Summary of Phase 1.
This survey provides more
details about this issue.
According to the Cluster Rule,
the bleach plant scrubber
used must reduce the HAPs
by 99% or have an aggregate
chlorinated HAP loading of
under 10 ppmv.Mills already
using fluidized bed type
bleach plant scrubbers are
easily meeting these requirements.The primary reason thesescrubbers are successful is due to the fact they easily
handle bleach plant emission
surges.There are also many
other reasons: >
ԙ fluidized bed gas scrubbing
technology. >

The RuleӔ

In general, the Cluster RuleӔ
requires that pulp bleaching
processes switch from those
using elemental chlorine (Cl >
2 )to those using oxidants and
specialized extraction
sequences that produce
minimal or no amount of
adsorbable organic halide
(AOX) compounds.These
AOX compounds, though low
in concentration, are
suspected of causing adverse
ecological and health effects.
Elemental chlorine can produce
chloroform and other Hazar-
dous Air Pollutants (HAPs). >
RotaBed and ScrubPac ٙ are trademarks of Bionomic Industries,Inc.Patent Pending. size="-2">