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The association angle: CPPA on Canada, TAPPI JOURNAL, January 1997, Vol. 80(1)

The association angle: cppa on canada, TAPPI JOURNAL, January 1997, Vol. 80(1)

The French pulp and paper industry in review, TAPPI JOURNAL, June 1997, Vol. 80(6)

The french pulp and paper industry in review, TAPPI JOURNAL, June 1997, Vol. 80(6)

Capitalizing on an environmental enterprise, TAPPI JOURNAL, March 1997, Vol. 80(3)

Capitalizing on an environmental enterprise, TAPPI JOURNAL, March 1997, Vol. 80(3)

Improving softwood mechanical pulp properties with ophiostoma piliferum, TAPPI JOURNAL, March 1997, Vol. 80(3)

Improving softwood mechanical pulp properties with ophiostoma piliferum, TAPPI JOURNAL, March 1997, Vol. 80(3)

Black liquor evaporator upgrades— life cycle cost analysis, TAPPI Journal March 2021

ABSTRACT: Black liquor evaporation is generally the most energy intensive unit operation in a pulp and paper manufacturing facility. The black liquor evaporators can represent a third or more of the total mill steam usage, followed by the paper machine and digester. Evaporator steam economy is defined as the unit mass of steam required to evaporate a unit mass of water from black liquor (i.e., lb/lb or kg/kg.) The economy is determined by the number of effects in an evaporator train and the system configuration. Older systems use four to six effects, most of which are the long tube vertical rising film type. Newer systems may be designed with seven or even eight effects using falling film and forced circulation crystallization technology for high product solids. The median age of all North American evaporator systems is 44 years. Roughly 25% of the current North American operating systems are 54 years or older. Older systems require more periodic maintenance and have a higher risk of unplanned downtime. Also, older systems have chronic issues with persistent liquor and vapor leaks, shell wall thinning, corrosion, and plugged tubes. Often these issues worsen to the point of requiring rebuild or replacement. When considering the age, technology, and lower efficiency of older systems, a major rebuild or new system may be warranted. The intent of this paper is to review the current state of black liquor evaporator systems in North America and present a basic method for determining whether a major rebuild or new installation is warrant-ed using total life cycle cost analysis (LCCA).

Summaries from TAPPI Journal, Paper360º May/June 2024

Treatment of softwood kraft pulps with peroxymonosulfate before oxygen delignification, TAPPI JOURNAL, August 1993, Vol. 76(8)

Treatment of softwood kraft pulps with peroxymonosulfate before oxygen delignification, TAPPI JOURNAL, August 1993, Vol. 76(8)

The effects of alkaline leaching on pulp bleachability and physical properties, TAPPI JOURNAL, December 1993, Vol. 76(12)

The effects of alkaline leaching on pulp bleachability and physical properties, TAPPI JOURNAL, December 1993, Vol. 76(12)

Biobleaching of softwood kraft pulp with white-rot fungus izu-154, TAPPI JOURNAL, January 1993, Vol. 76(1)

Biobleaching of softwood kraft pulp with white-rot fungus izu-154, TAPPI JOURNAL, January 1993, Vol. 76(1)

Formation of acidic sulfates in kraft recovery boilers, TAPPI JOURNAL, July 1993, Vol. 76(7)

Formation of acidic sulfates in kraft recovery boilers, TAPPI JOURNAL, July 1993, Vol. 76(7)