Pulp and Paper Industry

Emerging Waste Water Treatment Technologies

Pratima Bajpai

• Publisher: Elsevier
• Year: 2017
• Print ISBN: 9780128110997
• eBook ISBN: 9780128111000
• Topic: Technology & Engineering
• Subtopic: Chemical & Biochemical Engineering
• Index: Technology & Engineering

Pulp and Paper Industry: Emerging Waste Water Treatment Technologies is the first book which comprehensively reviews this topic. Over the past decade, pulp and paper companies have continued to focus on minimizing fresh water use and effluent discharges as part of their move towards sustainable operating practices. Three stages—basic conservation, water reuse and water recycling—provide a systematic approach to water resource management. Implementing these stages requires increased financial investment and better utilization of water resources.The ultimate goal for pulp and paper companies is to have effluent-free factories with no negative environmental impact. The traditional water treatment technologies that are used in paper mills are not able to remove recalcitrant contaminants. Therefore, advanced water treatment technologies are being included in industrial wastewater treatment chains aiming to either improve water biodegradability or its final quality.This book discusses various measures being adopted by the pulp and paper industry to reduce water consumption and treatment techniques to treat wastewater to recover it for reuse. The book also examines the emerging technologies for treatment of effluents and presents examples of full-scale installations.- Provides thorough and in-depth coverage of advanced treatment technologies which will benefit the industry personnel, pulp manufacturers, researchers and advanced students- Presents new treatment strategies to improve water reuse and fulfill the legislation in force regarding wastewater discharge- Presents viable solutions for pulp and paper manufacturers in terms of wastewater treatment- Presents examples of full-scale installations to help motivate mill personnel to incorporate new technologies

Chapter 1

Introduction

Abstract

Large amounts of water and energy in the form of steam and electricity are required for paper manufacturing. The process is water-use intensive relative to most other industries, but the amount of water consumed represents a small fraction of the overall water used. There have been significant improvements in both water use and effluent quality in the pulp and paper industry. While environmental effects of treated effluents are sometimes observed, aquatic communities are usually not altered by well-treated mill effluents. The general introduction on the use of water in the pulp and paper industry is presented in this chapter.

Keywords

Effluent quality; Environmental effects; Pulp and paper industry; Water consumption; Water use

The pulp and paper industry uses a lot of water in its processes. Large amounts of water and energy in the form of steam and electricity other than the raw materials are necessary for paper manufacturing. Water is required for several purposes in a pulp or paper mill. It is used to carry fibers and chemicals, to cool process equipment, for cleaning, and for many other purposes. Water is also essential for developing the chemical bonds between cellulose fibers, which give paper its strength. Frost & Sullivan published market insight research, which has shown that about 85% of the water that the pulp and paper industry consumes is only used for processing, ultimately producing large volumes of contaminated wastewater (Ravi, 2002). Therefore, the most important environmental concerns in the pulp and paper industry are the contaminant emission to water and air and also high energy consumption. Moreover, the wastes and residuals resulted by production are increasingly affecting the environmental concerns (Hynninen, 1998).

According to Ramezani et al. (2011), there is a close relationship between the forest products industry and water cycle (Fig. 1.1). Water is a vital and important source in pulp, paper, and paperboard manufacturing. A large amount of water required in the factories is supplied by surface water resources such as lakes and rivers, and the remaining is fed by water wells, with the depth ranging from very shallow to more than 1000 m.

Development of new processes and other technical improvements have decreased the freshwater consumption over the years. This progress has been stimulated by harsher demands from environmental authorities and a wish by many companies to be regarded as environmentally friendly. The ultimate goal for the pulp and paper industry has been an effluent-free factory with no negative impact on the environment. This type of factory does not exist and is probably a utopia, but with advanced water management and recycling of different process streams, there are operational paper mills demonstrating very low freshwater consumption.

Industrial wastewater streams pose a serious threat to human life, plants, and animals, and to the ecosystems of the bodies of water they enter. One of the main causes of surface water and groundwater contamination is industrial discharge from textile, pulp and paper, pharmaceutical, and other chemical industries. Environmental regulatory requirements have become tougher because of increased awareness of the human health and ecological risks associated with the environmental contaminants. As a result of legislation, a lack of water resources, and greater customer demands, the world’s pulp and paper industry must find ways to reduce water consumption.

Figure 1.1 Relationship between forest products industry and water cycle. Reproduced with permission NCASI, 2009. Water Profile of the United States Forest Products Industry. Technical Bulletin No. 0960. National Council for Air and Stream Improvement, Inc., Research Triangle Park, NC.

The pulp and paper industry is ranked as the world’s third largest consumer of water and is consequently producing high amounts of wastewaters (Sevimli, 2005). High water consumption often goes hand in hand with high energy consumption, since more pumping and treating is needed (Sdguide Org, 2008).

Process water is needed for several process stages, including raw materials preparation (e.g., wood chip washing), cooking, pulp washing, screening, bleaching, transportation, dilution, and formation (Sappi, 2012). The amount is very much dependent on the type of process and chemicals that are used in the process (Ince et al., 2011; Fontanier et al., 2006). The consumption levels can vary from mill to mill because of both general and process-related reasons, such as paper grades produced, raw materials used, and plant structure. Furthermore, local boundary conditions, such as requirements on wastewater discharge, have an impact on the consumption level. According to Jung and Kappen (2014), high specific effluent volumes occur particularly in the production of specialty paper grades (Fig. 1.2). These mills are often faced with structural handicaps, which cause increased specific effluent volumes: smaller paper machines, frequent grade changes, low production rates, and often very high quality requirements on the final product. The lowest water requirements can be found in mills that produce packaging papers, such as corrugated base paper or board. Some of these mills have already managed to close their water circuits completely, resulting in a zero effluent production.

Figure 1.2 Grade-specific effluent volume in the German paper industry. Reproduced with permission Jung, H., Kappen, J., 2014. Water in the paper industry. Professional Papermaking, 11–13.

The discharged water effluents can contain significant amounts of toxic substances, which can cause death to the living organisms in receiving waters and affect the terrestrial ecosystems negatively. The effluents can also cause thermal impact, slime growth, scum formation, and loss of aesthetic beauty in the environment (Pokhrel and Viraraghavan, 2004; Ali and Sreekrishnan, 2001; Zhao et al., 2014; Bajpai and Bajpai, 1997; Zhu et al., 2012; BREF, 2015; Buyukkamaci and Koken, 2010; Mauchauffee et al., 2012; Scott and Ollis, 1995; Thompson et al., 2001; Riffat, 2013; Ranade, 2014; Spellman, 2014; Blanco et al., 2016; Ince et al., 2011; Hermosilla et al., 2010; Fatta-Kassinos et al., 2016). Considerable volumes of cooling ...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Figures
• List of Tables
• Preface
• Acknowledgments
• Chapter 1. Introduction
• Chapter 2. The Pulp and Paper Industry
• Chapter 3. Best Available Techniques
• Chapter 4. Water Usage in the Pulp and Paper Processes
• Chapter 5. Reduction of Water Consumption in Pulp and Paper Mills
• Chapter 6. External Treatment Technologies Used for Pulp and Paper Mill Effluents
• Chapter 7. Emerging Technologies for Wastewater Treatment
• Chapter 8. Examples of Full-Scale Installations
• Chapter 9. Future Perspectives
• Glossary of Terms
• Index