scholarly journals PENGARUH PENAMBAHAN XILANASE PADA PROSES PEMUTIHAN SISTEM ELEMENTAL CHLORINE FREE (ECF)

2016 ◽  
Vol 3 (01) ◽  
Author(s):  
Krisna Septiningrum ◽  
Susi Sugesty
Keyword(s):  
Solid Phase ◽  
Acacia Mangium ◽  
Kappa Number ◽  
Bacillus Circulans ◽  
Extractive Content ◽  
Physical Strength ◽  
Bleached Pulp ◽  
Elemental Chlorine ◽  
Ecf Bleaching

This research aims to investigate the effect of xylanase pretreatment on elemental chlorine free (ECF) bleaching process, the quality of bleached pulp and wastewater characteristics. At first, xylanase was produced from Bacillus circulans using solid-phase fermentation and then used for pre- bleaching of Acacia mangium and commercial pulp (Kappa Number of 12-16) and then bleached with D0ED1D2 bleaching sequences. The bleached pulp obtained was tested for physical and optical properties; COD and AOX content of wastewater generated were tested as well. The results showed that the xylanase pretreatment increase the brightness, physical strength (tensile and bursting index) of Acacia mangium and commercial pulp at xylanase dose of 0.5 kg/ton. The xylanase decrease the extractive content of Acacia mangium pulp but increase it at a commercial pulp. In contrary, the dirt content of Acacia mangium pulp was increase while it was decrease at a commercial pulp. These were obtained at a dose of xylanase of 0.5 kg/ton. The addition of xylanase on prebleaching process could increase the COD value but decrease significantly the AOX content in effluent.Keywords: xylanase, Bacillus circulans, pre-bleaching, Acacia mangium, ECF  ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh perlakuan awal xilanase pada pemutihan pulp sistem elemental chlorine free (ECF), kualitas pulp putih dan pengaruhnya terhadap karakteristik air limbah yang dihasilkan. Mula-mula, xilanase diproduksi dari Bacillus circulans menggunakan fermentasi fase padat kemudian digunakan pada perlakuan awal pemutihan (pre-bleaching) pulp Acacia mangium dan pulp komersial (Bilangan Kappa 12-16). Pulp lalu diputihkan dengan urutan D0ED1D2. Pulp putih yang diperoleh diuji sifat fisik dan optiknya, sedangkan air limbah yang  diperoleh diuji kandungan COD dan AOX. Hasil penelitian menunjukkan aplikasi xilanase dapat meningkatkan derajat putih, kekuatan fisik (indeks tarik dan retak) pulp Acacia mangium dan komersial pada dosis xilanase sebesar 0,5 kg/ton. Xilanase dapat menurunkan kandungan ekstraktif pada pulp Acacia mangium namun meningkatkan kandungan ekstraktif pada pulp komersial. Hal sebaliknya terjadi pada jumlah noda pada lembaran. Jumlah noda meningkat pada pulp Acacia mangium namun menurun pada pulp komersial pada dosis xilanase 0,5 kg/ton. Penambahan xilanase pada proses pre-bleaching meningkatkan kandungan COD pada air limbah proses pemutihan yang dihasilkan namun dapat menurunkan kandungan AOXKata kunci: xilanase, Bacillus circulans, pra-pemutihan, Acacia mangium, ECF

ECF Bleaching of Pre-Hydrolyzed Larix Kraft Pulp for Production of Dissolving Pulp

2013 ◽  
Vol 634-638 ◽  
pp. 386-390
Author(s):  
Zhi Li ◽  
Jun Li ◽  
Jun Xu
Keyword(s):  
Hydrogen Peroxide ◽  
Chlorine Dioxide ◽  
Kraft Pulp ◽  
Kappa Number ◽  
Alkaline Extraction ◽  
Polymerization Degree ◽  
Oxygen Delignification ◽  
Elemental Chlorine ◽  
Pulp Properties ◽  
Ecf Bleaching

Elemental Chlorine Free (ECF) bleaching sequence of O1/O2D0EOPD1D2 was adopted to bleach the pro-hydrolyzed Larix kraft pulp, where O1/O2 was two-stage oxygen delignification without interstage treatment, D was chlorine dioxide bleaching, EOP was pressurized alkaline extraction strengthened by hydrogen peroxide. Keeping bleaching temperature and time unchanged, sodium hydroxide charge(NaOH) in O1 stage, chlorine dioxide(ClO2) charge in D0 stage and D2 stage were studied, pulp properties such as brightness, kappa number, alpha-cellulose, pentosan and polymerization degree were measured and compared to establish optimal bleaching conditions. Results show that the optimal charge of NaOH in O1 stage is 2.5%, ClO2 in D0 and D2 stage are 2.5%, 0.6%, and the pulp gained at the optimal bleaching conditions has the properties of 93.9% of alpha-cellulose, 2.60% of pentosan, 375.5 ml/g of viscosity and 86.6%ISO of brightness.

scholarly journals The Effect of Pulping Process Variable and Elemental Chlorine Free Bleaching on the Quality of Oil Palm Trunk Pulp

2018 ◽  
Vol 8 (02) ◽  
pp. 85
Author(s):  
Wieke Pratiwi ◽  
Andoyo Sugiharto ◽  
Susi Sugesty
Keyword(s):  
Physical Properties ◽  
Oil Palm ◽  
Process Analysis ◽  
Chemical Properties ◽  
Acacia Mangium ◽  
Raw Material ◽  
Fiber Morphology ◽  
Oil Palm Trunk ◽  
Bleached Pulp ◽  
Elemental Chlorine

Oil Palm Trunk (OPT) is a non-wood cellulosic raw material which is not yet widely utilized in pulping and papermaking. Research on the utilization of abundant Oil Palm Trunk (OPT) from Sabah (Malaysia) and Lebak (West Java Province) for pulp production was carried out using kraft and soda anthraquinone processes with active alkali (AA) of 13-17%. The raw material was chipped and depithed as pretreatment. Bleaching of pulp was carried out using Elemental Chlorine Free (ECF) process. Analysis of raw material covered physical and chemical properties, and fiber morphology. Both OPT fibers were classified into the moderate fiber length (1.05-1.37 mm). Sabah OPT were very bulky with the chips pile density of 102.16 kg/m3 and 62.91 kg/m3 for undepithed and depithed OPT, respectively. The physical properties of OPT pulps were comparable to that of Acacia mangium pulp. With respect to the bleachability and physical properties, pulping of Lebak OPT using kraft or soda-anthraquinone process with AA of 15% were considered as optimum condition. Depithing on Sabah OPT with high pith content could increase physical properties of pulp. ODEoDnD bleaching sequence on pulps from Sabah OPT gave satisfactory results with respect to the physical properties. Since Sabah OPT had a high pith content, the yields of bleached pulp were relatively low (24.67-26.73%). However, the physical properties of the undepithed and depithed Sabah OPT bleached pulp were higher compared to those of the SNI of Leaf Bleached Kraft Pulp (LBKP).Keywords: depithing, Elemental Chlorine Free, bleached pulp, physical properties, LBKP Pengaruh Variabel Proses Pulping dan Pemutihan Elemental Chlorine Free pada Kualitas Pulp Batang Kelapa SawitAbstrakBatang Kelapa Sawit adalah bahan baku selulosa non-kayu yang belum banyak digunakan dalam pembuatan pulp dan kertas. Penelitian tentang pemanfaatan Batang Kelapa Sawit (BKS) dari Sabah (Malaysia) dan Lebak (Provinsi Jawa Barat) yang berlimpah untuk produksi pulp menggunakan proses kraft dan soda antrakuinon dengan alkali aktif (AA) kisaran 13-17% telah dilakukan. Penyerpihan dan proses depithing bahan baku dilakukan sebagai perlakuan awal. Pemutihan pulp dilakukan menggunakan Elemental Chlorine Free (ECF). Analisis bahan baku mencakup sifat fisik dan kimia, serta morfologi serat. Kedua serat BKS dapat diklasifikasikan sebagai serat moderat dengan panjang 1,05-1,37 mm. BKS dari Sabah sangat ruah dengan densitas tumpukan serpih masing-masing 102,16 kg/m3 untuk yang belum di-depithing dan 62,91 kg/m3 untuk yang telah di-depithing. Sifat fisik pulp BKS sebanding dengan pulp dari Acacia mangium. Sehubungan dengan kemampuan pemutihan dan sifat fisik, pembuatan pulp BKS dari Lebak menggunakan proses kraft atau soda-antrakuinon dengan AA 15% adalah kondisi optimal. Depitihing BKS dari Sabah dengan kandungan pith yang tinggi dapat meningkatkan sifat fisik pulp. Pemutihan dengan urutan ODEoDnD untuk pulp BKS dari Sabah memberikan hasil sifat fisik yang memuaskan. BKS dari Sabah memiliki kandungan pith yang tinggi sehingga rendemen pulp yang diputihkan relatif rendah (24,67-26,73%). Namun, sifat-sifat fisik pulp putih BKS dari Sabah yang belum dan telah di-depithing lebih tinggi dibandingkan SNI Pulp Kraft Putih Kayudaun (LBKP).Kata kunci: depithing, Elemental Chlorine Free, pulp putih, sifat fisik, LBKP

scholarly journals CHARACTERISATION OF MORINGA OLEIFERA (DRUMSTICK) WOOD FOR PULP AND PAPER MAKING

2021 ◽  
Vol 55 (3-4) ◽  
pp. 255-262
Author(s):  
ARVIND SHARMA ◽  
GUNJAN DHIMAN ◽  
PRITI S. LAL ◽  
RAVI D. GODIYAL ◽  
BIPIN P. THAPLIYAL
Keyword(s):  
Mechanical Strength ◽  
Moringa Oleifera ◽  
Acacia Mangium ◽  
Strength Properties ◽  
Kraft Pulping ◽  
Kappa Number ◽  
Pulp And Paper ◽  
Paper Making ◽  
Bleached Pulp ◽  
Optimized Conditions

"Moringa oleifera (drumstick) wood was evaluated in terms of its chemical composition, morphological features, Kraft pulping behavior, ECF bleaching and mechanical strength properties – important parameters for pulp and paper making – in comparison with Acacia mangium. Moringa oleifera was found to have the following composition: holocellulose 65.5%, lignin 20.5%, pentosan 11.6%, -cellulose 40.5% and extractives content of 5.15%, which made it comparable with the Acacia mangium wood sample. The alkali prehydrolysis of Moringa oleifera was carried out using 2% NaOH at 150 °C. The prehydrolysis liquor (PHL) was found to contain 50.9 mg/kg of calcium, 5140 mg/kg of potassium and 312 mg/kg of iron content. The prehydrolysis step was followed by Kraft pulping in order to obtain chemical grade pulp of kappa number 15-16 under optimized conditions. The Moringa oleifera pulp was bleached using the DEpD bleaching sequence to reach 85% brightness (ISO). The bleached pulp had an average fiber length of 1.21 mm, which was higher than that of Acacia mangium – 0.782 mm. The mechanical strength properties of the unbleached and bleached pulps, such as tear, tensile and burst indices, were also determined to show their suitability for pulp and paper production."

Extension of a steady-state chlorine dioxide brightening model for Z-ECF bleaching of softwood kraft pulps

TAPPI Journal ◽  
2021 ◽  
Vol 20 (3) ◽  
pp. 186-197
Author(s):  
BRIAN N. BROGDON ◽  
LUCIAN A. LUCIAN
Keyword(s):  
Steady State ◽  
Linear Relationship ◽  
Chlorine Dioxide ◽  
Current Model ◽  
Kappa Number ◽  
Kraft Pulps ◽  
Current Investigation ◽  
Elemental Chlorine ◽  
Steady State Model ◽  
Ecf Bleaching

Earlier studies developed a steady-state model to predict the brightness and/or bleach consumption during the chlorine dioxide brightening (D1) of softwood pulps produced by conventional elemental-chlorine-free (ECF) sequences. This model relates the chlorine dioxide consumed to the brightness gains predicated upon an asymptotic D1 brightness limit, an incoming D1 pulp brightness, and an equation parameter (β11). The current investigation examines the application of this model to ECF sequences that use ozone delignification (Z-ECF). Literature D1 data from various Z-ECF bleaching studies, which investigated OZ, OD0/Z, and OZ/D0 delignification, were fitted to the model. The β11 parameter was found to be linearly correlated to the entering kappa number. Interestingly, this linear relationship was found to be identical to the relationships observed when modeling the D1 stage for conventional ECF and chlorine-based bleach sequences. Subtle differences in D1 brightening response in the model among the various bleach sequences are reflected by incoming pulp brightness (at the same kappa number). The current model is used to illustrate how alterations to Z-ECF delignification affect D1 brightening and chlorine dioxide consumption.

Improved steady-state models for chlorine dioxide delignification sequences that include washer carryover effects

TAPPI Journal ◽  
2015 ◽  
Vol 14 (2) ◽  
pp. 93-103 ◽  
Author(s):  
BRIAN N. BROGDON
Keyword(s):  
Steady State ◽  
Chlorine Dioxide ◽  
Control Strategies ◽  
Kappa Number ◽  
Carryover Effects ◽  
Advanced Process Control ◽  
Elemental Chlorine ◽  
Plant Data ◽  
State Models ◽  
Ecf Bleaching

In previous studies, generalized steady-state models were proposed to approximate the chlorine dioxide demand needed for the delignification of softwood and hardwood pulps, where the kappa number entering the bleach plant can fluctuate. However, these expressions neglect the effect of dissolved solids with the stock that originate from incomplete pulp washing. In this study, the original elemental chlorine-free (ECF) models are modified to include the effects of carryover from brownstock or post-oxygen washing. The stoichiometric bleach consumption from carryover, based on its composition, was calculated from various literature sources. The majority of the bleach demand (about 70%) results from the dissolved lignin contained in the brownstock carryover, with the remainder resulting from the inorganic sulfur constituents (e.g., sulfide and thiosulfate). When the effect of brownstock carryover was taken into account, the modified models accurately predicted the amount of chlorine dioxide consumed for a given delignification level (about ±0.1% chlorine dioxide) vs. actual bleach plant data. The improved models can be used to gauge the level of washer carryover entering the bleach plant if this parameter is not regularly monitored by the mill. Additionally, these modified expressions could be integrated into advanced process control strategies for ECF bleaching where the washer carryover or dissolved lignin entrainment is measured with online sensors.

scholarly journals Modification of chlorine dioxide bleaching of Gmelina arborea (gamar) pulp

2017 ◽  
Vol 52 (4) ◽  
pp. 247-252 ◽  
Author(s):  
M Sarwar Jahan ◽  
MM Uddin ◽  
MA Kashem
Keyword(s):  
Chlorine Dioxide ◽  
Kraft Pulp ◽  
Kappa Number ◽  
Side Reactions ◽  
Gmelina Arborea ◽  
Pulp Bleaching ◽  
Bleaching Process ◽  
Elemental Chlorine ◽  
Extraction Stage ◽  
Ecf Bleaching

Elemental Chlorine Free (ECF) pulp bleaching is now the dominant pulp bleaching process in globally. In most bleachery, chlorine dioxide is over-consumed. About two thirds of the chlorine dioxide is wasted in useless side reactions. In the study, kraft pulp from Gmelina arborea (gamar wood) was bleached by ECF bleaching in modified sequences. Oxygen prebleaching was carried out to decrease ClO2 requirement, which reduced kappa number of kraft pulp by 47.6% and increased pulp brightness by 21.7 percent points. Several sequences were tested based on the application of limited charges of ClO2 during successive ClO2and extraction stage. Application of this concept allowed a 33% reduction of ClO2 to reach target brightness. The kraft pulp could not reach target brightness of 80% in DED sequences using even 30 kg ClO2/ton of pulp, while splitting of same amount of ClO2 charge into DEDED sequences reached the pulp brightness to 81.1%. But oxygen delignified kaft pulp reached 79.6% brightness using 25 kg ClO2/ton of pulp in DED sequences. In the splitting of ClO2 charge into DEDED sequences, Oxygen pulp reached to 85% brightness by using only 20 kg ClO2/ton pulp.Bangladesh J. Sci. Ind. Res. 52(4), 247-252, 2017

Effect of Neutral Xylanase Pretreatment on ECF Bleaching of KP Bamboo Pulp with Low Kappa Number

2012 ◽  
Vol 549 ◽  
pp. 260-264
Author(s):  
Jin Bao Li ◽  
Mei Yun Zhang ◽  
Xin Xing Xia ◽  
Yi Juan Liu
Keyword(s):  
Kappa Number ◽  
Residual Lignin ◽  
Color Reversion ◽  
Bleached Pulp ◽  
Lignin Removal ◽  
Bamboo Pulp ◽  
Ecf Bleaching ◽  
Optimum Charge

At present, most of the studies of Xylanase auxiliary bleaching focused on in the alkaline or acid conditions. It was investigated in this paper that Neutral Xylanase had been used to pretreat the oxygen delignified KP bamboo pulp with low kappa number. The effect of Xylanase on the follow-up ECF bleaching was discussed, especially highlighting the principle of the residual lignin removal and improvement of pulp’s brightness. Results showed that the effect of neutral xylanase pretreatment on ECF bleaching of KP bamboo pulp was obvious. The pulp with a higher brightness and brightness stability could be obtained in this way. The optimum charge of xylanase is 0.6IU•g-1, and The brightness of the bleached pulp could reach 87.8%ISO, the color reversion value 0.016, viscosity 764mL•g-1. It was 2.9%ISO higher in brightness, 59mL•g-1 higher in viscosity, but the color reversion value is only 30.2% of the later, compared to the pulp without xylanase pretreatment.

scholarly journals A Method to Reduce Steam Consumption of ECF Bleaching Based on Operation Optimizing

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 928
Author(s):  
Shaoxu Chen ◽  
Zhichao Ma ◽  
Jiang Liu ◽  
Jingjing Yang ◽  
Yongjun Yin ◽  
...  
Keyword(s):  
Paper Industry ◽  
Urgent Problem ◽  
Quality Indices ◽  
Steam Consumption ◽  
Energy And Environment ◽  
Bleached Pulp ◽  
The Cost ◽  
Ecf Bleaching ◽  
Reducing Energy

Development of paper industry has been restricted by resources, energy and environment deeply; further reducing energy consumption becomes an urgent problem to be solved. In this paper, the calculating model of steam consumption in bleaching process is established under the premise of ensuring product quality and controlling bleaching cost. Then, an optimization model for minimizing steam consumption is constructed. Compared with before optimization, the steam consumption of the optimized bleaching system reduced by 19.48% (0.5014 t/adt) at a loss of 0.11% brightness (0.1 ISO%) and 5.17% viscosity (33 mL/g). The amount of chemicals should be increased to ensure the quality of the pulp while decreasing the bleaching temperature to reduce steam consumption, the cost of bleaching pulp has decreased by 1.62% (3.19 USD/adt) after optimization. The verification experiments showed all the pulp quality indices can meet the requirements of bleached pulp.

Effect of introducing ozone in elemental chlorine free bleaching of pulp on generation of chlorophenolic compounds

2020 ◽  
Vol 35 (4) ◽  
pp. 559-568
Author(s):  
Sandeep Kumar Tripathi ◽  
Nishi Kant Bhardwaj ◽  
Himadri Roy Ghatak
Keyword(s):  
Optical Properties ◽  
Wheat Straw ◽  
Oxygen Demand ◽  
Elemental Chlorine ◽  
Wheat Straw Pulp ◽  
Pulp Properties ◽  
Organic Halogens ◽  
Ecf Bleaching ◽  
Adsorbable Organic Halogens

AbstractEffect of using ozone before elemental chlorine free (ECF) bleaching of oxygen delignified wheat straw pulp produced following soda-anthraquinone pulping on bleaching effluent and pulp properties was studied. The effluent generated during bleaching of pulp contains high amount of adsorbable organic halogens (AOX), chemical oxygen demand (COD), biochemical oxygen demand (BOD) and highly toxic chlorophenolic compounds. This study is aimed to utilise green chemistry approach during bleaching of one of the abundantly used agro residue wheat straw for improving the quality of bleaching effluent and pulp properties. Introducing ozone stage before ECF bleaching resulted in significant reduction of chloriphenolic compounds like chlorocatechols by 48.9 %, chloroguaiacols by 33.3 %, chlorovanillins by 28.4 % and chlorophenols by 26.7 % in the effluent compared to those of control. Incorporation of ozone before ECF bleaching BOD, COD, AOX and colour were reduced by 40.0 %, 41.1 %, 46.7 % and 57.8 %, respectively, as compared to control. Optical properties like brightness and whiteness of the pulp bleached using ozone were also improved by 2.5 units and 4.0 units, respectively as compared to that with control.

Chemical, anatomical, and technology aspects of Eucalyptus benthamii and Eucalyptus dunii for use in an integrated pulp and paper mill

TAPPI Journal ◽  
2015 ◽  
Vol 14 (2) ◽  
pp. 73-81 ◽  
Author(s):  
GISELY SAMISTRARO ◽  
PETER W. HART ◽  
JORGE LUIZ COLODETTE ◽  
RICARDO PAIM
Keyword(s):  
Energy Levels ◽  
Black Liquor ◽  
Basic Density ◽  
Paper Mill ◽  
Frost Tolerance ◽  
Strength Properties ◽  
Kappa Number ◽  
Pulp Yield ◽  
Chemical Compositions ◽  
Physical Strength

Eucalyptus dunii has been commercially used in southern Brazil because of its relatively good frost tolerance and adequate productivity in the winter months. More recently, interest has grown in cultivating Eucalyptus benthamii Maiden & Cambage, which presents even superior frost tolerance compared to E. dunii and is highly productive as well. The quality of E. benthamii for pulp production is not yet proven. Thus, the chemical, anatomical, and technological aspects of pulp made from E. benthamii were compared with those of E. dunii for unbleached paper production. Samples of E. benthamii chips were obtained and analyzed for their basic density, chemical composition, higher heating value, trace elemental analysis, and chip size distribution. The chips were kraft cooked using conditions that produced a 74 ± 6 kappa number. The pulps were characterized for kappa number, yield, viscosity, and morphologic characteristics (e.g., length, wall thickness, and coarseness). Black liquor was analyzed for total solids, organics, inorganics, sodium sulfide, sodium hydroxide, and sodium carbonate. Brownstocks were beaten at five different energy levels in a Valley beater, and the physical strength properties of 120 g/m² handsheets were measured to develop a beater curve. The results of this study showed differences in delignification between the two woods and lower pulp yield for E. benthamii , which are related to their chemical compositions and basic densities. The E. benthamii studied in this work exhibited higher amounts of lignin and extractives, lower carbohydrate content, and lower basic density. However, cooking a blend of the two woods afforded good results in pulping and in physical pulp properties.

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