scholarly journals Influence of Input Variables over the Wood Digestion in a Sulfite Pulp Mill for Biorefinery Purposes

2015 ◽  
Vol 6 (2) ◽  
pp. 160
Author(s):  
Cristina Rueda ◽  
Carlos Tejedor ◽  
Natalia Quijorna ◽  
Ana Andrés ◽  
Alberto Coz

Eucalyptus globulus is the most profitable specie in Europe for pulping. However, in recent years some diseases and pests have caused its defoliation, affecting the available quantity of wood. In this sense, the mills are studying how to avoid the loss of pulp yield as well as the optimization of byproducts in order to take advantage of every component present in the wood using biorefinery processes. One of the possible options is to complete the consumption of E. globulus with other species such as Eucalyptus nitens.The objective of this paper is to study the behavior of both species related to the dissolving pulp manufacturing process as well as the characteristics of the resulting products. Parameters that can be very useful for the evaluation of the raw material, such as the growing data or density of both species, have been compared. Major attention has been focused on the composition of both species and how it affects the characteristics of the possible final products.E. nitens presents good results of forestry characteristics, being better than E. globulus in terms of growing and resistance to frosts. The cellulose content of both species is similar, however the digestion process in the case of E. nitens needs to be improved in order to optimize the involved energy and the obtained products.

2011 ◽  
Vol 3 (1) ◽  
pp. 24
Author(s):  
Yuniarti Yuniarti

The objective of this study was to determine the chemical components of three kinds of social forestry timber of Jengkol, Madang, and Bangkinang, where wood samples was procured from Loksado South Kalimantan. The analysis was conducted according to TAPPI Standard with three replications for each sample. Result shows that Jengkol wood contained 44.73% of cellulose, 79.19% of holocellulose, 32.14% of lignin, 4.08% of extractive and 3.42% of ash. Madang wood contained 45.02% of cellulose, 80.05% of holocellulose, 31.60% of lignin, 4.06% of extractive and 4.59% of ash. Bangkinang wood contained 45.76% of cellulose, 72.84% of holocellulose, 20.90% of  lignin, 2.89% of extractive and 3.9% of ash. This research indicated that among three social forestry timber investigated, the Bangkinang wood is better than two others as sources of raw material for pulp and paper due to the highest cellulose content and lowest lignin and extractives contents.Keywords: chemical properties, Jengkol, Madang, Bangkinang


2015 ◽  
Vol 12 (1) ◽  
pp. 1-12 ◽  
Author(s):  
E.O. Onuorah ◽  
J.T. Nwabanne ◽  
E.L.C. Nnabuife

The objective of this study was to determine the pulping and paper making potentials of oil palm (E guineensis). Fibrous material from the whole trunk (WT), empty fruit bunch (EFB, fronds (FDS) and depithed trunk (DT) were evaluated using proximate chemical analysis, fiber morphological and related characteristics. Effect of active alkali (AA) % as Na2O on kraft pulping properties and the handsheet paper propertie was studied. Proximate chemical analysis reveal acceptable cellulose content for EFB (43.51%), FDS (51.13%) and DT (53.80%) while WT (32.44) is unacceptable. Low lignin content obtained (17.8−21.8%) suggests easier pulping characteristics. The high % NaOH solubility of WT (26.05%) and FDS (32.1%) suggest potential of high effluent loads. Fiber morphological studies revealed that approximately 83% of fibers are ≤ 1.5 mm in length thus putting oil palm as a short fiber source. The slenderness ratio ranges from 33.44 to 82.80; Runkelratio from 0.40 to 0.63; flexibility co-efficient from 57.20 to 71.46 and rigidity co-efficient from 0.29 to 0.43. Studies of pulping properties reveal that as active alkali % was increased the percentage total pulp yield, % screened pulp yield, % screened rejects, pulp kappa number, klason lignin and tear index of resultant pulp/handsheet all/each decreased. Conversely, as active alkali % was increased the Brust index, double fold number, breaking length, tensile index of paper handsheets and pulp brightness were each enhanced. It was concluded that in pulping of WT AA% should be < 14 and EFB pulping should be ≤ 14 in order to have acceptable yield. Also in order to have acceptable tear index, AA% should be ≤ 16. It is being recommended that trunks should be depithed in order to have acceptable yield. The fibrous material from oil palm make acceptable raw material for paper making and are good hardwood substitutes. Paper produced when bleached can be used for printing and writing papers while the unbleached grades can be used for wrapping and package papers and for corrugated boards.


2020 ◽  
Vol 20 (4) ◽  
pp. 120-124
Author(s):  
Glenn Mochamad Rayhan ◽  
Salsabila Fachrina ◽  
Rizka Amalia

Paper production has been identified with industries that destroy forests (deforestation). Utilizing alternative wood substitute raw materials, such as pineapple leaves can be one solution to the problem. Pineapple plants can produce more than 70 leaves with cellulose content in the leaves which reaches 69.5-71.5%, so it has the potential to be used as raw material for paper. The organosolv process was chosen as a pulp manufacturing process because it produces high purity in the byproducts (lignin and hemicellulose), high pulp yield, easy recovery of black liquor and no sulfur element, making it safer for the environment. This study aims to determine the most influential factors in the organosolv pulping process with a factorial experimental design method 23. Variables used include solvent types (ethanol and acetic acid), pulp cooking time (60 minutes and 110 minutes) and types of leaf dryness (wet leaves) and dried leaves). From the results of the analysis, the most influential factor in the organosolv pulping process is the type of solvent (ethanol). Optimal operating conditions were obtained for solvent ethanol, cooking time of 60 minutes with wet leaves, where cellulose content was 96.31% and lignin content decreased by 17.80% in dry pulp.


TAPPI Journal ◽  
2013 ◽  
Vol 12 (6) ◽  
pp. 9-15 ◽  
Author(s):  
TOMI HIETANEN ◽  
JUHA TAMPER ◽  
KAJ BACKFOLK

The use of a new, technical, high-purity magnesium hydroxide-based peroxide bleaching additive was evaluated in full mill-scale trial runs on two target brightness levels. Trial runs were conducted at a Finnish paper mill using Norwegian spruce (Picea abies) as the raw material in a conventional pressurized groundwood process, which includes a high-consistency peroxide bleaching stage. On high brightness grades, the use of sodium-based additives cause high environmental load from the peroxide bleaching stage. One proposed solution to this is to replace all or part of the sodium hydroxide with a weaker alkali, such as magnesium hydroxide. The replacement of traditional bleaching additives was carried out stepwise, ranging from 0% to 100%. Sodium silicate was dosed in proportion to sodium hydroxide, but with a minimum dose of 0.5% by weight on dry pulp. The environmental effluent load from bleaching of both low and high brightness pulps was significantly reduced. We observed a 35% to 48% reduction in total organic carbon (TOC), 37% to 40% reduction in chemical oxygen demand (COD), and 34% to 60% reduction in biological oxygen demand (BOD7) in the bleaching effluent. At the same time, the target brightness was attained with all replacement ratios. No interference from transition metal ions in the process was observed. The paper quality and paper machine runnability remained good during the trial. These benefits, in addition to the possibility of increasing production capacity, encourage the implementation of the magnesium hydroxide-based bleaching concept.


Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 447
Author(s):  
Miguel Alfonso Quiñones-Reveles ◽  
Víctor Manuel Ruiz-García ◽  
Sarai Ramos-Vargas ◽  
Benedicto Vargas-Larreta ◽  
Omar Masera-Cerutti ◽  
...  

This study aimed to evaluate and compare the relationship between chemical properties, energy efficiency, and emissions of wood and pellets from madroño Arbutus xalapensis Kunth, tázcate Juniperus deppeana Steud, and encino colorado Quercus sideroxyla Humb. & Bonpl. in two gasifiers (top-lit-up-draft (T-LUD) and electricity generation wood camp stove (EGWCS)) in order to determine the reduction of footprint carbon. In accordance with conventional methodologies, we determined the extracts and chemical components (lignin, cellulose, holocellulose), and the immediate analyses were carried out (volatile materials, fixed carbon, ash content and microanalysis of said ash), as well as the evaluation of emission factors (total suspended particulate matter (PM2.5), CO, CO2, CH4, black carbon (BC), elemental carbon (EC), and organic carbon (OC)). The results were statistically analyzed to compare each variable among species and gasifiers. The raw material analyzed showed how the pH ranged from 5.01 to 5.57, and the ash content ranged between 0.39 and 0.53%. The content values of Cu, Zn, Fe, Mg, and Ca ranged from 0.08 to 0.22, 0.18 to 0.19, 0.38 to 0.84, 1.75 to 1.90, and 3.62 to 3.74 mg kg−1, respectively. The extractive ranges from cyclohexane were 2.48–4.79%, acetone 2.42–4.08%, methanol 3.17–7.99%, and hot water 2.12–4.83%. The range of lignin was 18.08–28.60%. The cellulose content ranged from 43.30 to 53.90%, and holocellulose from 53.50 to 64.02%. The volatile material range was 81.2–87.42%, while fixed carbon was 11.30–17.48%; the higher heating value (HHV) of raw material and pellets presented the ranges 17.68–20.21 and 19.72–21.81 MJ kg−1, respectively. Thermal efficiency showed statistically significant differences (p < 0.05) between pellets and gasifiers, with an average of 31% Tier 3 in ISO (International Organization for Standardization) for the T-LUD and 14% (ISO Tier 1) for EGWCS, with Arbutus xalapensis being the species with the highest energy yield. The use of improved combustion devices, as well as that of selected raw material species, can reduce the impact of global warming by up to 33% on a cooking task compared to the three-stone burner.


1995 ◽  
Vol 06 (05) ◽  
pp. 681-692
Author(s):  
R. ODORICO

A Neural Network trigger for [Formula: see text] events based on the SVT microvertex processor of experiment CDF at Fermilab is presented. It exploits correlations among track impact parameters and azimuths calculated by the SVT from the SVX microvertex detector data. The neural trigger is meant for implementation on the systolic Siemens microprocessor MA16, which has already been used in a neural-network trigger for experiment WA92 at CERN. A suitable set of input variables is found, which allows a viable solution for the preprocessing task using standard electronic components. The response time of the neural-network stage of the trigger, including preprocessing, can be estimated ~10 μs. Its precise value depends on the quantitative specifications of the output signals of the SVT, which is still in development. The performance of the neural-network trigger is found to be significantly better than that of a conventional trigger exclusively based on impact parameter data.


2018 ◽  
Vol 33 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Dan Huo ◽  
Qiulin Yang ◽  
Guigan Fang ◽  
Qiujuan Liu ◽  
Chuanling Si ◽  
...  

Abstract Eucalyptus residues from pulp mill were pretreated with aqueous ammonia soaking (AAS) method to improve the efficiency of enzymatic hydrolysis. The optimized condition of AAS was obtained by response surface methodology. Meanwhile, hydrogen peroxide was introduced into the AAS system to modify the AAS pretreatment (AASP). The results showed that a fermentable sugar yield of 64.96 % was obtained when the eucalypt fibers were pretreated at the optimal conditions, with 80 % of ammonia (w/w) for 11 h and keeping the temperature at 90 °C. In further research it was found that the addition of H2O2 to the AAS could improve the pretreatment efficiency. The delignification rate and enzymatic digestibility were increased to 64.49 % and 73.85 %, respectively, with 5 % of hydrogen peroxide being used. FTIR analysis indicated that most syringyl and guaiacyl lignin and a trace amount of xylan were degraded and dissolved during the AAS and AASP pretreatments. The CrI of the raw material was increased after AAS and AASP pretreatments, which was attributed to the removal of amorphous portion. SEM images showed that microfibers were separated and explored from the initial fiber structure after AAS pretreatment, and the AASP method could improve the destructiveness of the fiber surface.


2019 ◽  
Vol 9 (2) ◽  
pp. 12-20
Author(s):  
Julio Warmansyah ◽  
Dida Hilpiah

 PT. Cahaya Boxindo Prasetya is a company engaged in the manufacture of carton boxes or boxes. The company's activities also include cutting and printing services using machinery and human power. The problem faced in this company is the difficulty of predicting the amount of inventory of raw materials that will be  included in the production. The remaining raw materials for production will be used as the final stock to get the minimum, the goal is to reduce excess stock Overcoming this problem, fuzzy logic is used to predict raw material inventories by focusing on the final stock. In this study using Fuzzy Sugeno, with three input variables, namely: initial inventory, purchase, production, while the output is the final stock. Determination of prediction results using defuzzification using the average concept of MAPE (Mean Absolute Percentage Error). The results obtained, using the Fuzzy Sugeno method can predict the inventory of raw materials with a MAPE value of 38%. 


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