High levels of elements such as calcium, magnesium, potassium, sodium, iron,

Manganese, zinc, and phosphorus. These trace elements are important to the

Nutrition of trees, and should be returned into the forest, though this is not always

Permitted.

This chapter will focus briefly on the impact of the pulping process. The dominant

Process for chemical pulp production is the kraft or sulfate process. Apart

From some specific differences, other processes such as sulfite pulping or soda

Pulping have a rather comparable environmental impact. Although the operation

Of a pulping process requires energy. modern mills do not require fossil fuel as

The source for all energy is combustion of the compounds dissolved during the

Pulping process. The resultant emissions are the release of volatile compounds

During the high-temperature pulping process and during brown stock washing.

Evaporation and combustion of the recovered liquor causes additional emissions.

In alkaline pulping the operation of the lime kiln represents an emission source.

Handbook of Pulp. Edited by Herbert Sixta

Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

ISBN: 3-527-30999-3

©2006 WILEY-VCHVerlag GmbH&Co.

Handbook of Pulp

Edited by Herbert Sixta

The standard measures to reduce the impact of volatile and odorous compounds

Is by the sophisticated management of these sources. This comprises their collection,

Combustion and scrubbing of the remaining noncondensable gases. These

Methods are applied similarly for the on-site generation of bleaching chemicals

Such as chlorine dioxide and ozone. The build-up of nonprocess elements (chloride

Ions, potassium, or transition metals) in the process requires the introduction

Of cleaning steps that cause additional liquid or solid emissions. Washing of the

Fibers in the bleach plant removes organic matter, these dissolved compounds

Require a biological treatment of the effluent.

The impact of pulping, and the measures to control and limit the emissions,

Have been described in a variety of publications, with the European Commission

publishing standards in 2000 [2]. Integrated Pollution and Prevention Control

(IPPC) is used to describe the “best available techniques in the pulp and paper

industry”. Similarly guidelines for a potential kraft pulp mill in Tasmania [3]

Describe the requirements for an environmentally sound operation.

10.2

A Glimpse of the Historical Development

Over the years, pulp mills have become significantly larger with the development

Of technology. During the late nineteenth century, a mill with an annual production

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