scholarly journals Chemical and Fibre Properties by Lemon Grass in Chemical Pulping for Pulp Industry

2020 ◽  
Vol 616 ◽  
pp. 012080
Author(s):  
Zawawi Daud ◽  
Husnul Azan Tajarudin ◽  
Nair Gomesh ◽  
Ragunathan Santiagoo ◽  
Halizah Awang ◽  
...  
Keyword(s):  
Fibre Properties ◽  
Pulp Industry ◽  
Lemon Grass ◽  
Chemical Pulping

Organic material dissolved during oxygen-alkali pulping of hot water extracted birch sawdust

TAPPI Journal ◽  
2015 ◽  
Vol 14 (4) ◽  
pp. 237-244 ◽  
Author(s):  
JONI LEHTO ◽  
RAIMO ALÉN
Keyword(s):  
Acetic Acid ◽  
Betula Pendula ◽  
Cooking Time ◽  
Hot Water ◽  
Partial Hydrolysis ◽  
Chemical Pulping ◽  
Black Liquors ◽  
Aliphatic Carboxylic Acids ◽  
Hydrolysis Of ◽  
Cooking Conditions

Untreated and hot water-treated birch (Betula pendula) sawdust were cooked by the oxygen-alkali method under the same cooking conditions (temperature = 170°C, liquor-to-wood ratio = 5 L/kg, and 19% sodium hydroxide charge on the ovendry sawdust). The pretreatment of feedstock clearly facilitated delignification. After a cooking time of 90 min, the kappa numbers were 47.6 for the untreated birch and 10.3 for the hot water-treated birch. Additionally, the amounts of hydroxy acids in black liquors based on the pretreated sawdust were higher (19.5-22.5g/L) than those in the untreated sawdust black liquors (14.8-15.5 g/L). In contrast, in the former case, the amounts of acetic acid were lower in the pretreated sawdust (13.3-14.8 g/L vs. 16.9-19.1 g/L) because the partial hydrolysis of the acetyl groups in xylan already took place during the hot water extraction of feedstock. The sulfur-free fractions in the pretreatment hydrolysates (mainly carbohydrates and acetic acid) and in black liquors (mainly lignin and aliphatic carboxylic acids) were considered as attractive novel byproducts of chemical pulping.

CHEMICAL PULPING. Oxidative degradation of AOX in softwood-based kraft mill effluents from E C F bleachin g

2012 ◽  
Vol 27 (4) ◽  
pp. 707-713 ◽  
Author(s):  
Jukka Pekka lsoaho ◽  
Suvi Tarkkanen ◽  
Raimo Alen ◽  
Juha Fiskari
Keyword(s):  
Reaction Time ◽  
Oxidative Degradation ◽  
Cost Effective ◽  
Process Conditions ◽  
Main Process ◽  
Chemical Pulping ◽  
Kraft Mill ◽  
Organic Halogens ◽  
Aox Removal ◽  
Adsorbable Organic Halogens

Abstract Softwood-based kraft mill bleaching effluents from the initial bleaching stages D0 and E1 (the bleaching sequence being D0E 1D 1 E2D2) were treated by the oxidative Fenton method (H20rFeS04) to decompose organic pollutants contammg adsorbable organic halogens (AOX). Experiments designed using the Taguchi method were applied to predict the process conditions that would result in a cost-effective and adequate removal of AOX. In addition to the composition and concentration of the reagents (H202 and Fe2+), the main process parameters selected were temperature and reaction time, while pH was adj usted to an approximate value of 4 (the volumetric ratio of the mixed effluents D0:E 1 was 3 :2). The results indicated that an AOX removal of about 70% for this mixture ( corresponding to about 50% for the mill) was achieved when the eftluent samples were treated for 60 min at 70°C with H202 and Fe2+ at a concentration of 1 600 mg/1 and 28 mg/1, respectively.

Chemical pulping

2009 ◽  
Vol 24 (2) ◽  
pp. 172-182 ◽  
Author(s):  
Marta Bialik ◽  
Ali Moosavifar ◽  
Maria Sedin ◽  
Hans Theliander
Keyword(s):  
Chemical Pulping

scholarly journals Fibre development in an intensified mechanical pulping process

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christer Sandberg
Keyword(s):  
Production Process ◽  
Size Distribution ◽  
Specific Energy ◽  
Microscopic Level ◽  
Mechanical Pulp ◽  
Fibre Properties ◽  
Conventional Process ◽  
Fibre Development ◽  
Printing Paper ◽  
High Consistency

Abstract Mechanical pulp for printing paper can be produced with a process that involve much less equipment and that require much lower specific energy compared to conventional processes. Even though common evaluation methods, e.g. handsheet testing, have shown that the pulp quality is similar for the simplified and the conventional processes, it is not known how fibre properties, at the microscopic level, is developed with the simplified process. In this mill scale study, the fibre properties attained with an “intensified” mechanical pulping process, consisting of single stage high consistency double disc refining followed by two stage low consistency refining and no reject treatment was investigated. The simplified process was compared to a process with a reject system. The simplified process rendered fibres with higher degree of fibrillation, higher share of axial splits, lower fibre wall thickness but slightly lower length than the conventional process. The fibrillar fines size distribution of the two processes was different. The conventional process generated more of small fibrillar fines which probably explains the higher tensile index at given density for that process. The results show that it is possible to simplify the production process for mechanical pulp and reduce the specific energy with over 700 kWh/adt.

scholarly journals Physico-mechanical properties of plywood bonded with ecological adhesives from Acacia mollissima tannins and lignosulfonates

2017 ◽  
Vol 78 (3) ◽  
pp. 34813 ◽  
Author(s):  
Naima Rhazi ◽  
Mina Oumam ◽  
Abdessadek Sesbou ◽  
Hassan Hannache ◽  
Fatima Charrier-El Bouhtoury
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Phenol Formaldehyde ◽  
Waste Product ◽  
Formaldehyde Emission ◽  
Extraction Methods ◽  
Press Temperature ◽  
Pulp Industry ◽  
Pressing Time ◽  
Chemical Conditions

The objective of this research was to develop ecological adhesives for bonding plywood panels using lignosulfonates, a common waste product of the wood pulp industry, and natural tannin extracted from Moroccan bark of Acacia mollissima using different process. Natural tannin and lignin were used in wood adhesives formulation to substitute resins based on phenol and formaldehyde. To achieve this, the lignosulfonates were glyoxalated to enhance their reactivity and the used tannins obtained by three different extraction methods were compared with commercial mimosa tannin. The proportion of Acacia mollissima tannins and lignosulfonates, the pressing time, the pressing temperature, and the pressure used were studied to improve mechanical properties, and bonding quality of plywood panel. The properties of plywood panels produced with these adhesives were tested in accordance with normative tests. Thus, the tensile strength, and the shear strength were measured. The results showed that the performance of the plywood panels made using biobased tannin adhesives was influenced by physical conditions such as pressure, press temperature as well as by chemical conditions, such as the tannin-lignin ratio. It exhibited excellent mechanical properties comparable to commercially available phenol-formaldehyde plywood adhesives. This study showed that biobased adhesives formulations presented good and higher mechanical performance and no formaldehyde emission.

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