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Furnishing autohydrolyzed poplar weakly alkaline P-RC APMP to make lightweight coated base paper, TAPPI Journal February 2022

ABSTRACT: This work investigated the effects of autohydrolysis pretreatment severity on poplar (Populus tomentosa Carr.) woodchips used to make a type of high-yield pulp (HYP) known as preconditioning followed by refiner chemical treatment, alkaline peroxide mechanical pulp (P-RC APMP). It also investigated the ratios for partially replacing sodium hydroxide (NaOH) with magnesium oxide (MgO) in the high-consistency (HC) retention stage of the P-RC APMP process on the obtained HYP’s properties. The results show that the pretreatment severity of autohydrolysis at combined hydrolysis factor (CHF) = 10.77 and the 50 wt% ratio for partially substituting NaOH with MgO were the optimum conditions for making light-weight coated (LWC) base paper. Compared to the conventional P-RC APMP, the optimized P-RC APMP had similar bulk and higher tensile, burst, and tear indices, as well as opacity, but a slightly lower ISO brightness. When the optimized P-RC APMP and commercial softwood bleached sulfate pulp (SBKP) were blended to make LWC base paper, the most favorable pulp furnish was comprised of 50% optimized P-RC APMP and 50% commercial SBKP. The obtained LWC base paper handsheet had better bulk, and its other properties could also meet the require-ments of LWC base paper.

Calender barring review with experiences, TAPPI Journal July 2022

ABSTRACT: Excessive calender vibration affects all styles of calender stacks from single to multi-nip, all hard rolls, or a combination of hard and soft rolls. Calender vibration can be forced vibration or self-excited vibration. Forced vibration occurs at the first few harmonics of the calender roll rotational speeds and is caused by imbalance, misalignment, eccentricity, etc. Self-excited vibration, the focus of this paper, occurs at higher frequencies. Feedback paths for self-excited vibration must be understood in order to ameliorate the problem. This is presented in the context of the historical development of the theory of self-excited feedback mechanisms, followed by a survey of self-excited feedback mechanisms in various types of calender stacks. Methodology to determine which feed-back path is present and techniques to control or eliminate the resulting vibration follow. To obtain a flavor of the types of problems faced and practical remedial actions, a variety of experiences with barring issues are provided.

New Standards in Paper Production Water Use, Paper360º July/August 2022

Better Valves Improve Pulp and Paper Mill Safety, Paper360º July/August 2022

TAPPI Journal Summaries, Paper360º July/August 2022

TAPPI Journal Summaries, Paper360º July/August 2022

Application of Imaging Reflectometry to Studies of Print Mottle on Commercially Printed Coated Papers, TAPPI JOURNAL January 2008

Application of Imaging Reflectometry to Studies of Print Mottle on Commercially Printed Coated Papers, TAPPI JOURNAL January 2008

Great Expectations, Paper360º January 2008

Great Expecations, Paper360º January 2008

Transfer Pricing Strategies Begin at Home, Paper360º January 2008

Art of Transfer Pricing, Paper360º January 2008

Ask an Employment Lawyer: Wellness Programs: No Good Deed Goes Unpunished, Paper360° January 2008

Ask an Employment Lawyer, Paper360º January 2008

Can You Hear Me Now?, Paper360º January 2008

Thoughts from the Third Shift, Paper360º January 2008