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Na2CO3 as Alkali in Hydrogen Peroxide Bleaching of Softwood Kraft Pulp, 2011 International Pulp Bleaching Conference
Na2CO3 as Alkali in Hydrogen Peroxide Bleaching of Softwood Kraft Pulp, 2011 International Pulp Bleaching Conference
On the Role of Copper Ions in Alkaline Hydrogen Peroxide Bleaching of Kraft Pulps, 2011 International Pulp Bleaching Conference
On the Role of Copper Ions in Alkaline Hydrogen Peroxide Bleaching of Kraft Pulps, 2011 International Pulp Bleaching Conference
Modern Bleach Plant Advanced Process Control utilizing Inline Sensors and Model Predictive Control, 2011 International Pulp Bleaching Conference
Modern Bleach Plant Advanced Process Control utilizing Inline Sensors and Model Predictive Control, 2011 International Pulp Bleaching Conference
ASSESSMENT OF PULP MACHINE WHITEWATER QUALITY OF MARKET KRAFT PULP MILLS, 2011 International Pulp Bleaching Conference
Assessment of Pulp Machine Whitewater Quality of Market Kraft Pulp Mills, 2011 International Pulp Bleaching Conference
Combining Chlorine Dioxide and Molybdate Catalyzed Hydrogen Peroxide for Improved Delignification of Canadian Hardwood and Softwood Pulp, 2011 International Pulp Bleaching Conference
Combining Chlorine Dioxide and Molybdate Catalyzed Hydrogen Peroxide for Improved Delignification of Canadian Hardwood and Softwood Pulp, 2011 International Pulp Bleaching Conference
Near-Neutral Final Chlorine Dioxide Brightening: Theory and Practice, 2011 International Pulp Bleaching Conference
Near-Neutral Final Chlorine Dioxide Brightening: Theory and Practice, 2011 International Pulp Bleaching Conference
TCF bleaching character of Soda-anthraquinone pulp from oil palm frond, 2011 International Pulp Bleaching Conference
TCF bleaching character of Soda-anthraquinone pulp from oil palm frond, 2011 International Pulp Bleaching Conference
Web instability in the open draw and the impact on paper machine efficiency, TAPPI Journal May 2022
ABSTRACT: Paper is most likely to break in the first open draw on a paper machine where it is unsupported, wettest, and weakest. Tension is applied to peel the web from the roll surface, as well as minimize web flutter in the open draw. The average tension is well below the breaking point and is often set by adjusting the speed difference between the press and the next machine element by visually observing the behavior of the web. However, machine direction variations caused by instabilities in the paper machine can cause tension swings that exceed the strength of the web. Measurement of the web’s release point from press rolls on pilot and commercial paper machines was used to identify the cause of tension instabilities. Variations in the speed of the paper machine drives and the work of adhesion from the press roll surface were identified as key factors. Fluctuations of paper moisture, which affects the elastic modulus and strength of the web, appear to be less important.
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Magazine articles
Rethinking the paper cup — beginning with extrusion process optimizationfor compostability and recyc
ABSTRACT: More than 50 billion disposable paper cups used for cold and hot beverages are sold within the United States each year. Most of the cups are coated with a thin layer of plastic — low density polyethylene (LDPE) — to prevent leaking and staining. While the paper in these cups is both recyclable and compostable, the LDPE coat-ing is neither. In recycling a paper cup, the paper is separated from the plastic lining. The paper is sent to be recycled and the plastic lining is typically sent to landfill. In an industrial composting environment, the paper and lining can be composted together if the lining is made from compostable materials. Coating paper cups with a compostable performance material uniquely allows for used cups to be processed by either recycling or composting, thus creating multiple pathways for these products to flow through a circular economy.A segment of the paper converting industry frequently uses an extrusion grade of polylactic acid (PLA) for zero-waste venues and for municipalities with ordinances for local composting and food service items. The results among these early adopters reveal process inefficiencies that elevate manufacturing costs while increasing scrap and generally lowering output when using PLA for extrusion coating. NatureWorks and Sung An Machinery (SAM) North America researched the extrusion coating process utilizing the incumbent polymer (LDPE) and PLA. The trademarked Ingeo 1102 is a new, compostable, and bio-based PLA grade that is specifically designed for the extrusion coating process. The research team identified the optimum process parameters for new, dedicated PLA extrusion coating lines. The team also identified changes to existing LDPE extrusion lines that processors can make today to improve output.The key finding is that LDPE and PLA are significantly different polymers and that processing them on the same equipment without modification of systems and/or setpoints can be the root cause of inefficiencies. These polymers each have unique processing requirements with inverse responses. Fine tuning existing systems may improve over-all output for the biopolymer without capital investment, and this study showed an increase in line speed of 130% by making these adjustments. However, the researchers found that highest productivity can be achieved by specifying new systems for PLA. A line speed increase to more than 180% and a reduction in coat weight to 8.6 µm (10.6 g/m2 or 6.5 lb/3000 ft2) was achieved in this study. These results show that Ingeo 1102 could be used as a paper coating beyond cups.
Journal articles
Magazine articles
Addressing production bottlenecks and brownstock washer optimization via a membrane concentration system, TAPPI Journal July 2021
ABSTRACT: Advancements in membrane systems indicate that they will soon be robust enough to concentrate weak black liquor. To date, the economic impact of membrane systems on brownstock washing in kraft mills has not been studied and is necessary to understand the viability of these emerging systems and their best utilization.This study investigated the savings that a membrane system can generate related to brownstock washing. We found that evaporation costs are the primary barrier for mills seeking to increase wash water usage. Without these additional evaporation costs, we showed that our hypothetical 1000 tons/day bleached and brown pulp mills can achieve annual savings of over $1.0 MM when operating at higher dilution factors and fixed pulp production rate. We then investigated the impact of increasing pulp production on mills limited by their equipment. In washer-limited mill examples, we calculated that membrane systems can reduce the annual operating cost for a 7% production increase by 91%. Similarly, in evaporator-limited mill examples, membrane systems can reduce the annual operating cost for a 7% production increase by 86%. These results indicated that membrane systems make a production increase significantly more feasible for these equipment-limited mills.