Pulp and Paper
APPENDIX W PULP AND PAPER
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APPENDIX W
PULP AND PAPER
MICHIEL P. H. BRONGERS1 AND AARON J. MIERZWA1
SUMMARY AND ANALYSIS OF RESULTS Corrosion Control and Prevention
The $165 billion pulp, paper, and allied products industry supplies the United States with approximately 300 kg of paper per person per year. More than 300 pulp mills and more than 550 paper mills support its production. A typical pulp mill uses approximately 64 m3 of water per metric ton of pulp, and the combined pulp and paper manufacturers release approximately 100 thousand metric tons of toxic chemicals per year into the air, water, or land. The total annual corrosion costs for the pulp, paper, and paperboard industry, as determined as a fraction of the maintenance cost, is approximately $1.97 billion to $9.88 billion (average $5.928 billion per year). These estimates are between 1.2 percent and 6.0 percent of the total sales for the entire U.S. pulp and paper industry. The cost of corrosion for the pulp industry was only estimated at approximately $808.5 million per year. Paper production consists of a series of processes and can be roughly divided according to the five major manufacturing steps: (1) pulp production, (2) pulp processing and chemical recovery, (3) pulp bleaching, (4) stock preparation, and (5) paper manufacturing. Each manufacturing step has its own corrosion problems related to the size and quality of the wood fibers, the amount of and temperature of the process water, the concentration of the treatment chemicals, and the materials used for machinery construction. Examples of corrosion affecting production are: (1) corrosion products polluting the paper and (2) corrosion of rolls scarring the sheets of paper. Corrosion of components may also result in fractures or leaks in the machines, causing production loss and safety hazards.
Opportunities for Improvement and Barriers to Progress
Major changes in the paper-making process have occurred in the period
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Wii
APPENDIX W
PULP AND PAPER
MICHIEL P. H. BRONGERS1 AND AARON J. MIERZWA1
SUMMARY AND ANALYSIS OF RESULTS Corrosion Control and Prevention
The $165 billion pulp, paper, and allied products industry supplies the United States with approximately 300 kg of paper per person per year. More than 300 pulp mills and more than 550 paper mills support its production. A typical pulp mill uses approximately 64 m3 of water per metric ton of pulp, and the combined pulp and paper manufacturers release approximately 100 thousand metric tons of toxic chemicals per year into the air, water, or land. The total annual corrosion costs for the pulp, paper, and paperboard industry, as determined as a fraction of the maintenance cost, is approximately $1.97 billion to $9.88 billion (average $5.928 billion per year). These estimates are between 1.2 percent and 6.0 percent of the total sales for the entire U.S. pulp and paper industry. The cost of corrosion for the pulp industry was only estimated at approximately $808.5 million per year. Paper production consists of a series of processes and can be roughly divided according to the five major manufacturing steps: (1) pulp production, (2) pulp processing and chemical recovery, (3) pulp bleaching, (4) stock preparation, and (5) paper manufacturing. Each manufacturing step has its own corrosion problems related to the size and quality of the wood fibers, the amount of and temperature of the process water, the concentration of the treatment chemicals, and the materials used for machinery construction. Examples of corrosion affecting production are: (1) corrosion products polluting the paper and (2) corrosion of rolls scarring the sheets of paper. Corrosion of components may also result in fractures or leaks in the machines, causing production loss and safety hazards.
Opportunities for Improvement and Barriers to Progress
Major changes in the paper-making process have occurred in the period