Search

Use the search bar or filters below to find any TAPPI product or publication.

Showing 1,431–1,440 of 1,846 results (Duration : 0.012 seconds)
Journal articles
Open Access
CFD-modeling of fume formation in kraft recovery boilers, TAPPI JOURNAL March 2013

CFD-modeling of fume formation in kraft recovery boilers, TAPPI JOURNAL March 2013

Journal articles
Open Access
Increasing lime production while decreasing kiln pluggage through installation of the first LimeFlash lime kiln feed system in North America, TAPPI JOURNAL August 2012

Increasing lime production while decreasing kiln pluggage through installation of the first LimeFlash lime kiln feed system in North America, TAPPI JOURNAL August 2012

Journal articles
Open Access
Optical analysis of ink and other contaminants in process waters, TAPPI JOURNAL August 2012

Optical analysis of ink and other contaminants in process waters, TAPPI JOURNAL August 2012

Journal articles
Open Access
Process control for stickies, TAPPI JOURNAL February 2012

Process control for stickies, TAPPI JOURNAL February 2012

Journal articles
Open Access
Waste to power, TAPPI JOURNAL February 2012

Waste to power, TAPPI JOURNAL February 2012

Journal articles
Open Access
Influence of topcoat pigment particle size distribution on tail-edge pick resistance in sheet-fed offset printing, TAPPI JOURNAL June 2012

Influence of topcoat pigment particle size distribution on tail-edge pick resistance in sheet-fed offset printing, TAPPI JOURNAL June 2012

Journal articles
Magazine articles
Open Access
Preparation of regenerated cellulose from rice straw lignocellulosic waste and its use for reinforced paper products, TAPPI Journal July 2021

ABSTRACT: Rice straw waste is a lignocellulosic waste produced by farmers in large quantities. In this study, regenerated cellulose (RC) from rice straw was prepared by dissolving rice straw holocellulose (HC) in NaOH/Urea/Thio-urea/Water solution by the freeze-thawing process. The crystallinity index of RC was calculated at 31%, which is out of the crystallinity range of 39%•69% that has been previously suggested.The study indicated that the RC is amorphous with a low degree of polymerization (638) and higher hydroxyl group content as compared to HC. The fiber length of RC was found to be 26.7% shorter; however, the width of RC was 21.2% higher as compared to HC. Reduced kinked fiber content was observed in the fraction of RC (18.3%) as compared with HC (39.1%), and a higher curl index of fiber was observed more so in HC (10.5%) than RC (5.6%). Because of the regeneration process, the fiber length was reduced and a fines element content of about 96% was observed in RC compared to the initial fines content of HC (56.9%). Irrespective of the high fines element content of RC, the composite paper of rice straw bleached pulp and RC fibers was developed with an increase in the tensile index from 41.4 N.m/g to 71.2 N.m/g and an increase in the burst index from 4.7 kPa.m2/g to 5.3 kPa.m2/g with the addition of 5% and 15% RC, respectively. However, enhanced tear index of paper was observed up to 5% and then it declined upon further addition of RC. The study revealed that regenerated cellulose can be used as a strength additive to overcome the shortcomings of low mechanical properties in paper products.

Journal articles
Magazine articles
Open Access
Lignin carbohydrate complex studies during kraft pulping for producing paper grade pulp from birch, TAPPI Journal September 2020

ABSTRACT: Paper grade pulp production across the globe is dominated by the kraft process using different lignocellulosic raw materials. Delignification is achieved around 90% using different chemical treatments. A bottleneck for complete delignification is the presence of residual covalent bonds that prevail between lignin and carbohydrate even after severe chemical pulping and oxygen delignification steps. Different covalent bonds are present in native wood that sustain drastic pulping conditions. In this study, 100% birch wood was used for producing paper grade pulp, and the lignin carbohydrate bonds were analyzed at different stages of the kraft cook. The lignin carbohydrate bonds that were responsible for residual lignin retention in unbleached pulp were compared and analyzed with the original lignin-carbohydrate complex (LCC) bonds in native birch wood. It was shown that lignin remaining after pulping and oxygen delignification was mainly bound to xylan, whereas the lignin bound to glucomannan was for the most part degraded.

Journal articles
Magazine articles
Open Access
Co-pulping of Trewia nudiflora and Trema orientalis, TAPPI Journal June 2023

ABSTRACT: Trewia nudiflora, a fast-growing species, was evaluated as a pulpwood. The a-cellulose content of this species was 40.4% with a Klason lignin of 21.5%. It was characterized by shorter fibers with a thin cell wall. The pulp yield was 40% with a kappa number of 16 at the conditions of 18% active alkali charge and 30% sulfidity for 2 h cooking at 170°C. T. nudiflora was similar to Trema orientalis in anatomical, morphological, and chemical composition; therefore, mixed chips at a 50:50 mixture ratio were cooked under optimum conditions. The pulp yield of mixed chip cooking was 45.4% with a kappa number of 19.4. The tensile and tear index of T. nudiflora pulps were 64.8 Nœm/g and 11.5 kPaœm2/g at 35 °SR, respectively. The mixed chips, T. nudiflora, and T. orientalis pulps showed above 81% brightness when bleached by D0(EP)D1 sequence using 20 kg chlorine dioxide (ClO2)/ton of pulp.

Journal articles
Open Access
Evaluation of a molybdenum sulfide reference electrode in hot alkaline solutions, TAPPI JOURNAL July 2010

Evaluation of a molybdenum sulfide reference electrode in hot alkaline solutions, TAPPI JOURNAL July 2010