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Control of malodorous gases emission from wet-end white water with hydrogen peroxide, TAPPI Journal October 2021

ABSTRACT: White water is highly recycled in the papermaking process so that its quality is easily deteriorated, thus producing lots of malodorous gases that are extremely harmful to human health and the environment. In this paper, the effect of hydrogen peroxide (H2O2) on the control of malodorous gases released from white water was investigated. The results showed that the released amount of total volatile organic compounds (TVOC) decreased gradually with the increase of H2O2 dosage. Specifically, the TVOC emission reached the minimum as the H2O2 dosage was 1.5 mmol/L, and meanwhile, the hydrogen sulfide (H2S) and ammonia (NH3) were almost completely removed. It was also found that pH had little effect on the release of TVOC as H2O2 was added, but it evidently affect-ed the release of H2S and NH3. When the pH value of the white water was changed to 4.0 or 9.0, the emission of TVOC decreased slightly, while both H2S and NH3 were completely removed in both cases. The ferrous ions (Fe2+) and the copper ions (Cu2+) were found to promote the generation of hydroxyl radicals (HOœ) out of H2O2, enhancing its inhibition on the release of malodorous gases from white water. The Fe2+/H2O2 system and Cu2+/H2O2 system exhibited similar efficiency in inhibiting the TVOC releasing, whereas the Cu2+/H2O2 system showed better perfor-mance in removing H2S and NH3.

Editorial: Seshadri Ramkumar: Nonwovens specialist and TTU professor joins TJ Editorial Board, TAPPI Journal October 2021

ABSTRACT: TAPPI and the TAPPI JOURNAL (TJ) editorial staff would like to welcome a new member to the TJ Editorial Board, Seshadri “Ram” Ramkumar, Ph.D., a professor in the Department of Environmental Toxicology at Texas Tech University (TTU) in Lubbock, TX. Readers will be familiar with Ram as a frequent contributor of guest editorials in TAPPI Journal on the topic of nonwovens.

How to Build a Maintenance 4.0 Roadmap for the Pulp and Paper Industry, Paper360º September/October 2021

How to Build a Maintenance 4.0 Roadmap for the Pulp and Paper Industry, Paper360º September/October 2021

Business Cycles • Questions Executives Need to Ask, Paper360º January/February 2020

Business Cycles • Questions Executives Need to Ask, Paper360º January/February 2020

Employee Selection Can Help Weather the ´Silver Tsunami’, Paper360º January/February 2020

Employee Selection Can Help Weather the ´Silver Tsunami’, Paper360º January/February 2020

Understanding extensibility of paper: Role of fiber elongation and fiber bonding, TAPPI Journal March 2020

ABSTRACT: The tensile tests of individual bleached softwood kraft pulp fibers and sheets, as well as the micro-mechanical simulation of the fiber network, suggest that only a part of the elongation potential of individual fibers is utilized in the elongation of the sheet. The stress-strain curves of two actual individual pulp fibers and one mimicked classic stress-strain behavior of fiber were applied to a micromechanical simulation of random fiber networks. Both the experimental results and the micromechanical simulations indicated that fiber bonding has an important role not only in determining the strength but also the elongation of fiber networks. Additionally, the results indicate that the shape of the stress-strain curve of individual pulp fibers may have a significant influence on the shape of the stress-strain curve of a paper sheet. A large increase in elongation and strength of paper can be reached only by strengthening fiber-fiber bonding, as demonstrated by the experimental handsheets containing starch and cellulose microfibrils and by the micromechanical simulations. The key conclusion related to this investigation was that simulated uniform inter-fiber bond strength does not influence the shape of the stress-strain curve of the fiber network until the bonds fail, whereas the number of bonds has an influence on the activation of the fiber network and on the shape of the whole stress-strain curve.

Achieving Progressive Quality Culture Through Analytical Problem Solving, Paper360º March/April 2021

Achieving Progressive Quality Culture Through Analytical Problem Solving, Paper360º March/April 2021

Uncovering Growth Opportunities in Graphic Papers, Paper360º March/April 2021

Uncovering Growth Opportunities in Graphic Papers, Paper360º March/April 2021

Cepi: Looking Toward a Carbon Neutral 2050, Paper360º March/April 2021

Cepi: Looking Toward a Carbon Neutral 2050, Paper360º March/April 2021

CORRECTION: ASPI Awards Honor Szymanski, Semanak, Paper360º May/June 2022