Multistage fiber fractionation of softwood chemical pulp through smooth-hole screen cylinders and its effects on paper properties

TAPPI Journal ◽  
2015 ◽  
Vol 14 (4) ◽  
pp. 259-267 ◽  
Author(s):  
S. JUNAID S. QAZI ◽  
MASITA MOHAMAD ◽  
JAMES A. OLSON ◽  
D. MARK MARTINEZ
Keyword(s):  
Physical Properties ◽  
Strength Properties ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Aperture Size ◽  
Fractionation Process ◽  
Small Aperture ◽  
Paper Properties ◽  
Fiber Fractionation

Pressure screens are used to fractionate fibers on the basis of aspect ratio to obtain high value longfiber rejects and less desirable fines-rich accepts. Fiber fractionation is more practical and of maximum economic and commercial benefits when a mill can make use of all obtained fractions. We have demonstrated the potential of upgrading the reject fraction through a multistage fractionation process of a northern bleached softwood kraft pulp while isolating the remaining low-value pulp to be used as a raw material for a novel fiber-based product. The optimum operating conditions such as volumetric reject ratio, Rv; aperture velocity, Vs; and screen aperture size to carry out efficient fractionation were determined for the screens with 0.5-mm, 0.8-mm, and 1.0-mm apertures. This work shows that a high fines percentage in the accept fraction and increased fiber length in the reject fraction can be obtained when operating the pressure screen at a higher Rv and lower Vs using the screen cylinder with the small aperture size (0.5 mm). Feed and fractionated streams of pulp were used to study the effects on the physical properties of paper. Handsheets were made for strength properties of the unfractionated and fractionated pulps for comparisons. Significant improvements in the physical properties were observed after the removal of fines.

Does kraft hardwood and softwood pulp viscosity correlate to paper properties?

TAPPI Journal ◽  
2016 ◽  
Vol 15 (10) ◽  
pp. 643-651 ◽  
Author(s):  
ROBERT J. OGLESBY ◽  
HUMPHREY J. MOYNIHAN ◽  
RICARDO B. SANTOS ◽  
ASHOK GHOSH ◽  
PETER W. HART
Keyword(s):  
Physical Properties ◽  
Strength Loss ◽  
Strength Properties ◽  
Clear Correlation ◽  
Paper Properties ◽  
Physical Strength ◽  
Pulp Viscosity ◽  
Softwood Pulp ◽  
The Impact ◽  
Related Paper

The impact of commercially prepared, fully bleached pulp viscosity variation on handsheet physical properties was evaluated at different levels of pulp refining. Hardwood pulps from the same brownstock species mix, cooking parameters, and kappa numbers were processed through two different commercial bleach plants: one with a D0(EP)D1D2 sequence and the second with an OD0(EOP)D1 sequence. Additionally, a commercial softwood (predominately Scotts pine) brownstock pulp bleached by an OD0(EP)D1D2 sequence was employed in this study. Pulps with viscosities ranging from 14 to 21 mPa∙s were refined in a Valley beater to two freeness levels, and the associated handsheet physical properties were measured in this study. Over the pulp viscosity range of 14 to 21 mPa∙s, no clear correlation was found to exist between pulp viscosity and related paper physical properties. Finally, a series of laboratory prepared bleached pulps were purposely prepared under non-ideal conditions to reduce their final viscosities to lower values. Handsheets made from these pulps were tested in their unbeaten condition for physical strength properties. Significant and rapid strength loss occurred when the measured pulp viscosity dropped below 12 mPa∙s; overall strength properties showed no correlation to viscosity above the critical 12 mPa∙s value.

scholarly journals Evaluation of Rhododendron Luteum and Rhododendron Ponticum in Pulp and Paper Production

2020 ◽  
Vol 71 (4) ◽  
pp. 365-370
Author(s):  
Emre Birinci ◽  
Ahmet Tutuş ◽  
Mustafa Çiçekler
Keyword(s):  
Physical Properties ◽  
Kappa Number ◽  
Pulp And Paper ◽  
Raw Material ◽  
Paper Properties ◽  
Paper Production ◽  
Rhododendron Ponticum ◽  
Breaking Length ◽  
Pulp Properties ◽  
Cooking Conditions

In this study, Rhododendron luteum and Rhododendron ponticum were evaluated as raw material for pulp and paper production. 12 different sodium borohydride (NaBH4) added cooking trials were performed for each sample and kraft method was used for pulp production. Pulp properties, such as yield, kappa number and viscosity, and physical properties, such as breaking length and burst index, were determined for each trial. Besides, the effects of active alkali and NaBH4 on the pulp and paper properties were also examined. Optimum cooking conditions were obtained by using 18 % active alkali for NaBH4-free cooking experiments and 0.5 % NaBH4 and 18 % active alkali for NaBH4-added cooking experiments. In NaBH4-added pulping condition, the screened yield, kappa number and viscosity of R. luteum were found to be 43.4 %, 40.1 and 949 cm3/g1, respectively. The respective values for R. ponticum were 41.9 %, 44.5 and 885 cm3/g1. The screened yields of R. luteum and R. ponticum increased by about 2.8 % and 5.3 %, respectively, with 5 % addition of NaBH4 compared to NaBH4-free cooking experiments. Furthermore, with the addition of NaBH4, the kappa numbers decreased while the viscosity increased. The physical properties of the produced papers were also improved by using NaBH4 in cooking liquor. According to the obtained results, it was found that R. luteum and R. ponticum species can be evaluated for pulp and paper production.

Removal of Iron from Metallurgical Grade Silicon with Pressure Leaching

2011 ◽  
Vol 675-677 ◽  
pp. 873-876 ◽  
Author(s):  
Ke Qiang Xie ◽  
Zhan Liang Yu ◽  
Wen Hui Ma ◽  
Yang Zhou ◽  
Yong Nian Dai
Keyword(s):  
Particle Size ◽  
Reaction Time ◽  
Removal Efficiency ◽  
Acid Concentration ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Pressure Leaching ◽  
Metallurgical Grade Silicon ◽  
Grade Silicon

In this paper, removal of iron from metallurgical grade silicon with pressure leaching is carried out. We investigated the factors such as the concentration of hydrochloric, particle size of raw material ground, temperature, pressure and reaction time, which influenced on the removal of iron. The results show that the optimum operating conditions for pressure leaching in hydrochloride are: acid concentration 4 mol/L, diameter for raw material less than 50 μm, leaching temperature 160 0C，leaching pressure 2.0 MPa, leaching time 2.0 h. The content of iron residual in MG-Si powder was reduced to about 200 ppmw. The removal efficiency of iron is up to 90.90 %.

scholarly journals Characterization and Beneficiation of an Egyptian Nepheline Syenite Ore

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Abdel-Zaher M. Abouzeid ◽  
Abdel-Tawab A. Negm
Keyword(s):  
Magnetic Separation ◽  
Nepheline Syenite ◽  
Eastern Desert ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Oxide Content ◽  
Radioactive Elements ◽  
Original Rock ◽  
Alumina Recovery

Nepheline syenite ore is an essential constituent in ceramics and glass raw material meals, as a flux and as a source of alumina. The natural nepheline syenite rocks contain some undesired minerals, which are usually eliminated or reduced to the allowable limits by beneficiation. The present paper is concerned with characterization and beneficiation of an Egyptian nepheline syenite rock, at Abu Khruq locality, Eastern Desert, Egypt. The ore is exceptionally hard, with high crushing strength of 875 kg/cm2, and iron oxide content of about 6.5%. The grain size of the constituents is relatively large. In some samples, the iron oxides are disseminated within the feldspars and nepheline syenite crystals, or in cracks and fissures within the feldspars crystals. The rock contains some environmental hazardous elements such as uranium, thorium, and radon. Magnetic separation and flotation techniques were applied, separately or in combination. Under optimum operating conditions, magnetic separation followed by reverse anionic flotation gave a concentrate assaying 0.2% Fe2O3 and about 24% Al2O3 at alumina recovery of about 80%. The radioactive elements were reduced in the concentrate to lower levels than their levels in the original rock.

scholarly journals Synthesis of tert-amylbenzene for side-chain alkylation of cumene catalyzed by a solid superbase

2021 ◽  
Vol 10 (1) ◽  
pp. 874-881
Author(s):  
Xin Zhou ◽  
Ge Gao ◽  
Guangxiang He ◽  
Xiaoyan Guo ◽  
Haibo Jin ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Catalytic Reaction ◽  
Catalyst Concentration ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Side Chain ◽  
Operational Flexibility ◽  
Deactivation Of Catalyst ◽  
Solid Superbase

Abstract The side-chain alkylation of cumene and ethylene over a solid superbase catalyst K/KOH/γ-Al2O3 is investigated. The effects of the reaction temperature, pressure, and time on the conversion of cumene and selectivity of tert-amylbenzene (TAB) are discussed. The experimental results show that the conversion of cumene to tert-pentylbenzene increases with the increase in reaction temperature and ethylene pressure. The catalytic reaction has certain operational flexibility in terms of the reaction temperature, pressure, and time. In addition, the catalytic reaction can achieve directional conversion. The optimum operating conditions are obtained using a single factor test. The conversion of cumene is 99.8% and the selectivity toward TAB is 97.9% under catalyst concentration of 4 wt%, reaction temperature of 55°C, reaction pressure of 0.45 MPa, and reaction time of 30 min. The deactivation of catalyst is mainly caused by oxygen and water in the raw material.

PENGARUH WAKTU HIDROLISA DAN KONSENTRASI ASAM PADA HIDROLISA PATI KENTANG DENGAN KATALIS ASAM

EKUILIBIUM ◽  
2014 ◽  
Vol 13 (2) ◽  
Author(s):  
Inayati Inayati
Keyword(s):  
Acid Concentration ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Glucose Production ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Pseudo First Order Reaction ◽  
Glucose Content ◽  
Glucose Syrup

<p>Abstract: Potato has high content of carbohydrate (starch), so it can be used as raw material<br />for the glucose production. The basic principle to produce glucose from potatoes is hidrolysis of<br />polysaccharides (starch) into monosaccharides and disaccharides. In this work, potatoes were<br />converted into glucose syrup by hydrolysis using hydrochloric acid as catalyst. The aim of this<br />work is to study the effect of acid concentration on the reaction rate. Hydrolysis was carried out<br />with constant parameters, namely 20 gram of starch, 300 rpm of its rotational speed and the<br />operating temperature of 100°C, and variable parameters including acid concentration (0.5 N, 1<br />N, 1.5 N, and 2 N) and the hydrolyzing time (30 minutes, 60 minutes, 90 minutes, 120 minutes,<br />and 150 minutes). The glucose content were analyzed using the Lane-Eynon methode. The<br />data analysed showed the higher concentration of acid and time of hydrolysis caused higher<br />glucose formed. Optimum operating conditions was at 2 N HCL as catalyst. In this study, by<br />assuming a pseudo-first order reaction, the reaction rate constants obtained at range of 0.0047<br />to 0.0076/min.<br />Keywords: Potatoes, Starch, Hydrolysis, Acid concentration, Acid catalyst</p>

scholarly journals EKSTRAK DAUN SIRIH HIJAU DAN MERAH SEBAGAI ANTIOKSIDAN PADA MINYAK KELAPA

2013 ◽  
Vol 2 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Hermiati ◽  
Naomi Yemima Manalu ◽  
Mersi Suriani Sinaga
Keyword(s):  
Antioxidant Activity ◽  
Solvent Extraction ◽  
Leaf Extract ◽  
Coconut Oil ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Color Test ◽  
Betel Leaf ◽  
Material Powder

Extraction is the separation of a substance from the mixture, with the distribution of a solute between two solvents which can not be mixed to fetch solute from one solvent to another solvent. The purpose of this study was to determine the antioxidant activity found in betel leaf extract for coconut oil numbers peroxide analysis, antioxidant resistance, with Lovibond color test and to found variations in betel leaf types that produce the optimum operating conditions of antioxidants. In this study, green and red betel leaves extracted by using ethanol solvent, the extract is added to coconut oil and then tested peroxide number and color levels. The results obtained in this study were able to lower the number of betel leaves peroxide by 55.13% with the best optimum condition; volume of 150 ml of solvent, extraction time of 75 minutes, and stirring speed of 300 rpm for the raw material powder of red betel leaf.

scholarly journals Pengembangan Mesin Pencacah Tandan Kosong Sawit (TKS) dengan Metode Pemotongan Crusher

2014 ◽  
Vol 9 (2) ◽  
pp. 42
Author(s):  
Junaidi - ◽  
Anwar Kasim ◽  
Aidil Zamri ◽  
Sir Anderson
Keyword(s):  
Large Scale ◽  
Elastic Fiber ◽  
Testing Machine ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Design Parameters ◽  
Small Scale ◽  
Processing Unit ◽  
Engine Capacity

Palm empty fruit bunches (EFB) fiber content ± 70 % and can be used for elastic    fiber, matrix, mattresses, rugs and raw material fiber -based composite board products, but until now has not been utilized to the fullest . The problem is not the availability of processing unit generates EFB fiber in small scale . One of them is the processing unit thrasher EFB. EFB counter technology that exists today is a large scale that can only be owned by the oil palm industry with a capacity of ± 4,124 kg/hour. For small-scale fiber industry needs a minimum engine capacity of census enumerators ± 300 kg/hour, but this machine is not yet commercially available.In general, the purpose of this research is small scale EFB cutting machines with a capacity of 200-300 kg/hour, the design parameters and identify optimum operating conditions for each component with the technical test of the prototype. From the results obtained machine design an engine capacity of 300 kg/hour, with a few major components, namely counter unit, unit funnel in and out, frame and drive unit . From the results of design calculations obtained engine power 15 hp motor drive with 1450 RPM rotation with 3 phase. From the results of the testing machine in the first enumeration results obtained by the size of the pieces of shredded EFB ± 7 x 7 ( cm ), while the second enumeration stage shredded EFB size becoming smaller ± 3 x 3 ( cm ).

scholarly journals Rice Bran Oil Extraction as Trioxolane Raw Material

2020 ◽  
Vol 2 (1) ◽  
pp. 13-19
Author(s):  
Sri Handayani ◽  
Sofa Fajirah ◽  
Enjarlis Enjarlis
Keyword(s):  
Fatty Acids ◽  
Rice Bran ◽  
Animal Feed ◽  
Rice Bran Oil ◽  
Fatty Acid Analysis ◽  
Oil Extraction ◽  
Operating Conditions ◽  
Raw Material ◽  
Extraction Time ◽  
Optimum Operating

Rice bran is a byproduct of rice processing which was generally used for animal feed. Rice bran oil could be used as raw material in the fields of pharmaceuticals, cosmetics, and food oil. The purpose of this research is to extract rice bran into oil as a raw material for Trioxolane using n-Hexane solvent and purify the oil by adsorption using bentonite. Trioxolent compounds were obtained from ozonated fatty acids. Variable extraction time 2, 3 and 4 hours and use of bentonite 2.5, 5 and 7.5 grams from 10 ml of crude rice bran oil. The results obtained an oil yield of each variable extraction time 2, 3, and 4 hours respectively - the value is 8.4, 10, 11%. The optimum operating conditions were obtained by extraction time of 4 hours and refining 75% bentonite. The characteristics of rice bran oil has a moisture content of 8%, an acidic value of 67% mg NaOH/g sample, a peroxide number of 21 mgrek/g sample, an iod number of 46 mgI2 / g sample and the results of fatty acid analysis using GCMS is 33.5 % oleic acid, 24.8% Linoleic acid, 32.6% Palmitic acid.

Fractionation of epidermal cells from wheat straw pulp by flotation

TAPPI Journal ◽  
2015 ◽  
Vol 14 (4) ◽  
pp. 229-235
Author(s):  
MIKKO KARJALAINEN ◽  
ARI ÄMMÄLÄ ◽  
PÄIVI ROUSU ◽  
JOUKO NIINIMÄKI
Keyword(s):  
Wheat Straw ◽  
Cell Types ◽  
Strength Properties ◽  
Epidermal Cells ◽  
Raw Material ◽  
Paper Strength ◽  
Paper Properties ◽  
Vessel Elements ◽  
Wide Availability ◽  
Wheat Straw Pulp

The wide availability of wheat straw makes it a promising raw material for various fiber products, but its heterogeneity makes it a challenging material to use. In addition to reducing paper properties, some cell types cause processing problems such as silicate deposition and poor dewatering. The aims of this work were to examine the fractionation tendency of wheat straw pulp cells in flotation and to determine the effect of fractionation on paper strength properties. A cell type categorization based on automatic optical fiber analysis was used to assess fractionation. The results showed that epidermal cells can be selectively enriched from unbleached wheat straw pulp by flotation and other short cells had a tendency to become enriched in the overflow fraction. The underflow fraction consisted mostly of fibrous material, as well as vessel elements and long parenchyma cells. Removal of the epidermal cells from pulp will reduce its silicate content and improve the strength properties of the paper.

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