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Application of ATR-IR measurements to predict the deinking efficiency of UV-cured inks, TAPPI Journal January 2022
ABSTRACT: In recent years, ultraviolet (UV)-curable ink has been developed and widely used in various printing applications. However, using UV-printed products (UV prints) in recovered paper recycling causes end-product dirt specks and quality issues. A new method was developed that can distinguish UV prints from other prints by means of attenuated total reflectance infrared (ATR-IR) spectroscopy. Application of this method could allow more efficient use of UV prints as raw materials for paper recycling.First, a mill trial was performed using UV prints alone as raw materials in a deinked pulp (DIP) process. Second, test prints were made with four types of UV inks: a conventional UV ink and three different highly-sensitive UV inks. Each print sample had four levels of four-color ink coverage patterns (100%, 75%, 50%, and 25%). Next, deinkability of all prints was evaluated by laboratory experiments. Finally, each print was measured using the ATR-IR method, and the relationship between the IR spectra and deinkability was investigated. Mill trial results showed that UV prints caused more than 20 times as many dirt specks as those printed with conventional oil-based ink. There were variations in recycling performance among UV prints taken from bales used for the mill trial. Lab tests clearly revealed that not all UV-printed products lead to dirt specks. In order to clarify the factors that affected deinkability of UV prints, the print samples were investigated by lab experiments. Key findings from lab experiments include: • The number of dirt specks larger than 250 µm in diameter increased as the ink coverage increased. • Higher ink coverage area showed stronger intensity of ATR-IR spectral bands associated with inks. These results indicate that deinkability of UV prints could be predicted by analysis of ATR-IR spectra. • Finally, the method was applied for assessment of recovered paper from commercial printing presses. It was confirmed that this method made it possible to distinguish easily deinkable UV prints from other UV prints. Based on these findings, we concluded that the ATR-IR method is applicable for inspection of incoming recovered paper.
Journal articles
Magazine articles
Critical parameters for tall oil separation I: The importance of ration of fatty acids to rosin acids, TAPPI Journal September 2019
ABSTRACT: Tall oil is a valuable byproduct in chemical pulping of wood, and its fractions have a large spectrum of applications as chemical precursors, detergents, and fuel. High recovery of tall oil is important for the economic and environmental profile of chemical pulp mills. The purpose of this study was to investigate critical parameters of tall oil separation from black liquor. To investigate this in a controlled way, we developed a model test system using a “synthetic” black liquor (active cooking chemicals OH- and HS- ions), a complete process for soap skimming, and determination of recovered tall oil based on solvent extraction and colorimetric analysis, with good reproducibility. We used the developed system to study the effect of the ratio of fatty acids to rosin acids on tall oil separation. When high amounts of rosin acids were present, tall oil recovery was low, while high content of fatty acids above 60% significantly promoted tall oil separation. Therefore, manipulating the content of fatty acids in black liquor before the soap skimming step can significantly affect the tall oil solubility, and hence its separation. The findings open up chemical ways to improve the tall oil yield.
Magazine articles
Shop talk: reducing voc emissions with thermal oxidation units, TAPPI JOURNAL, December 1997, Vol. 80(12)
Shop talk: reducing voc emissions with thermal oxidation units, TAPPI JOURNAL, December 1997, Vol. 80(12)
Magazine articles
Operations teams run a woodyard, TAPPI JOURNAL, December 1996, Vol. 79(12)
Operations teams run a woodyard, TAPPI JOURNAL, December 1996, Vol. 79(12)
Magazine articles
Local section development efforts earn distinction for paul magnabosco, TAPPI JOURNAL, March 1996, Vol. 79(3)
Local section development efforts earn distinction for paul magnabosco, TAPPI JOURNAL, March 1996, Vol. 79(3)
Magazine articles
Modern management, technology, make skogn significant newsprint maker, TAPPI JOURNAL, March 1991, Vol. 74(3)
Modern management, technology, make skogn significant newsprint maker, TAPPI JOURNAL, March 1991, Vol. 74(3)
Magazine articles
Alkaline peroxide mechanical pulping of hardwoods, TAPPI JOURNAL, June 1991, Vol. 74(6)
Alkaline peroxide mechanical pulping of hardwoods, TAPPI JOURNAL, June 1991, Vol. 74(6)
Magazine articles
Mondi in south africa, TAPPI JOURNAL, April 1999, Vol. 82(4)
Mondi in south africa, TAPPI JOURNAL, April 1999, Vol. 82(4)
Journal articles
Magazine articles
Considerations in managing wastewater odor at pulp and paper operations, TAPPI Journal March 2022
ABSTRACT: Many pulp and paper mills are, at least periodically, faced with the release of odors that can migrate offsite and be considered a nuisance by nearby residents. At chemical pulp mills, perceptible odors associated with reduced sulfur compounds (RSCs) are common, many of which are highly perceptible owing to their low odor thresholds. As releases of RSCs and other odorous substances from production processes are progressively controlled, the proportional contribution from wastewater treatment systems to areal odors can increase. This review paper summarizes important fundamentals of odor generation, source identification, and control. Common odorous substances are identified, and mechanisms for their generation are summarized. Approaches for measuring odorous substances are detailed to enable more effective management, and various odor control strategies are discussed.
Magazine articles
Shop Talk: Screw presses in waste dewatering, December 1995 Tappi Journal [95Dec233.pdf]
Screw presses in waste dewatering, TAPPI JOURNAL, December 1995, Vol. 78(12)
