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1
Chambers, Paul GS, and Nuno MG Borralho. "A simple model to examine the impact of changes in wood traits on the costs of thermomechanical pulping and high-brightness newsprint production with radiata pine." Canadian Journal of Forest Research 29, no. 10 (October 1, 1999): 1615–26. http://dx.doi.org/10.1139/x99-127.
Повний текст джерелаАнотація:
A number of functions were investigated that related the costs of thermomechanical pulp (TMP) and high-brightness newsprint production, using Pinus radiata D. Don, to important pulp and paper quality (breeding objective) variables, including specific energy consumption and pulp handsheet tear and tensile strength, brightness, and opacity. Pulp handsheet quality traits were considered to be reasonable two-dimensional predictors of paper quality traits in this context. A specific production process that requires the use of a reinforcement kraft pulp and an artificial clay filler to improve the quality of paper produced from the bleached TMP fibres was investigated, similar to the production process used by Australian Newspaper Mills' Boyer Mill in Tasmania, Australia. Pulp and pulp handsheet quality variables could be explained by significant (P > 0.05) wood traits using multiple linear regression equations. This provided a method to predict the economic importance of each wood trait in relation to the thermomechanical production process investigated. The results showed that tracheid length, wood density, wood brightness, and tracheid coarseness were the best predictors of costs. Increases in tracheid length, wood density, and wood brightness and decreases in tracheid coarseness resulted in decreasing the total costs of TMP and high-brightness newsprint production.
2
Olmstead, Jennifer A., Jian H. Zhu, and Derek G. Gray. "Fluorescence spectroscopy of mechanical pulps III: Effect of chlorite delignification." Canadian Journal of Chemistry 73, no. 11 (November 1, 1995): 1955–59. http://dx.doi.org/10.1139/v95-241.
Повний текст джерелаАнотація:
Many paper and wood samples fluoresce, but the sources of the emission are not well understood. Fluorescence excitation and emission spectra of paper sheets prepared from thermomechanical pulp (TMP) and bleached chemithermomechanical pulp (BCTMP) showed that the emission from the BCTMP was significantly higher than that from the TMP. Removing almost all of the lignin from both pulps by means of an acid chlorite treatment did not reduce the fluorescence significantly. By means of an approximate correction for changes in sheet reflectivity caused by the chlorite treatment, the fluorescence intensity was found to increase with lignin removal. Clearly, fluorescence is not simply related to lignin content. Keywords: wood pulp, lignin, cellulose, fluorescence spectra, acid chlorite delignification.
3
HOUTMAN, CARL, and ERIC HORN. "Pilot trials of hemicelluloses extraction prior to thermomechanical pulp production: Part 1." May 2011 10, no. 5 (June 1, 2011): 21–28. http://dx.doi.org/10.32964/tj10.5.21.
Повний текст джерелаАнотація:
Pilot data indicate that wood chip pretreatment with oxalic acid reduced the specific energy required to make thermomechanical pulp. A combined oxalic acid/bisulfite treatment resulted in 21% refiner energy savings and 13% increase in brightness for aspen. A low level of oxalic acid treatment was effective for spruce. Energy savings of 30% was observed with no significant change in strength properties. Adding bisulfite did not significantly increase the brightness of the spruce pulp. For pine, the optimum treatment was a moderate level of oxalic acid, which resulted in 34% energy savings and an increase in strength properties. For all of these treatments 1–3 w/w % carbohydrates were recovered, which can be fermented to produce ethanol. The extract sugar solution contained significant quantities of arabinose.
4
Schirp, Arne, and Claudia Schirp. "Online Pre-Treatment of Thermomechanical Pulp with Emulsified Maleated Polypropylene for Processing of Extruded Thermoplastic Composites." Fibers 9, no. 3 (March 3, 2021): 17. http://dx.doi.org/10.3390/fib9030017.
Повний текст джерелаАнотація:
The effectiveness of maleated polypropylene (MAPP) in emulsified form for the pre-treatment of thermo-mechanical pulp (TMP) before extrusion with polypropylene fibres was evaluated. MAPP in pellet form, which was applied during the compounding step, served as a benchmark. In addition, commercial softwood flour was included as a reference. The influence of the temperature during the defibration process and the presence or absence of the coupling agent on composite performance were evaluated. Composites were processed with a high wood content of 70 wt.%, which is common for extruded profiles. It was found that TMP based on Robinia (Robinia pseudoacacia L.) conferred higher strength properties to the composites compared to TMP based on Scots pine (Pinus sylvestris L.), which was attributed to the higher length/diameter ratio of fibres in Robinia. However, under the conditions of this study, strength properties were superior and water uptake and swelling were reduced when wood flour was used instead of TMP. On the other hand, in many formulations, larger improvements in flexural and tensile strength due to MAPP were found for the TMP-based composites compared to the wood flour-based composites. This could be due to the larger surface/volume ratio for TMP compared to wood flour and more efficient stress transfer from fibres to the matrix. Results from X-ray photoelectron spectroscopy (XPS) showed that TMP surfaces were more hydrophobic than wood flour due to coverage with lignin, which reduced the effectiveness of MAPP. Esterification between the emulsified MAPP and fibre surfaces was determined using Fourier-Transform Infrared (FTIR) spectroscopy, but some non-activated maleic anhydride remained. Under the conditions of this study, MAPP added during compounding provided better performance compared to MAPP which included a non-ionic emulsifier and which was added during the refining process. Lower temperature (150 °C) during defibration was shown to be beneficial for the strength properties of composites compared to high temperature (180 °C) when MAPP was included in the formulations.
5
Laari, A., S. Korhonen, T. Tuhkanen, S. Verenich, and J. Kallas. "Ozonation and Wet Oxidation in the Treatment of Thermomechanical Pulp (TMP) Circulation Waters." Water Science and Technology 40, no. 11-12 (December 1, 1999): 51–58. http://dx.doi.org/10.2166/wst.1999.0694.
Повний текст джерелаАнотація:
Ozonation and wet oxidation were studied as means of the treatment of thermomechanical pulp (TMP) processing waters. There were two objectives of the experimental research concerning circulation waters: to reduce concentration of lipophilic wood extractives (LWEs) and to treat the concentrated residues from evaporation and membrane filtration by low-pressure catalytic wet oxidation. Ozone was found to selectively react with LWEs. The selectivity of ozonation defined as the ratio of the rate coefficients of the reactions with LWEs and other organic matter was found to be from 3 to 20. The reaction was always found to be of fast or moderate rate and, therefore, no dissolved ozone could be detected in water during ozonation. However, the ozone dose necessary to remove 90% of the LWEs in TMP water was found to be rather high, from 500 to 800 mg O3/l. This was determined by high content of organic matter, COD ranged between 3 and 6 kg O2/m3. The implementation of ozone for LWEs removal is therefore problematic from economical point of view. Catalytic low pressure-wet oxidation of membrane and evaporation concentrates was found to be effective: 50% of COD were removed under 150°C with subsequent increase of the wastewater biodegradability.
6
Jahren, Sigrun J., and Jukka A. Rintala. "The closure of water circuits by internal thermophilic (55 and 70°C) anaerobic treatment in the thermomechanical pulping process." Water Science and Technology 35, no. 2-3 (February 1, 1997): 49–56. http://dx.doi.org/10.2166/wst.1997.0480.
Повний текст джерелаАнотація:
The suitability of an internal thermophilic anaerobic treatment system for closing the water circuits in thermomechanical pulp (TMP) production was studied. The dissolution of wood organics in the water circuit was simulated by hot disintegration of TMP pulp, while the water system closure was simulated by repeated hot disintegration of TMP pulp with recirculated water. The upflow anaerobic sludge blanket (UASB) reactors were started at 55 and 70°C with mesophilic inoculum, and stable performances were established within 60 days at both temperatures. Closing the water circuits without internal treatment rapidly resulted in increased chemical oxygen demand (COD) in the recirculated water. In the closed, internally treated water circuits, the UASB reactors removed all the COD and ultraviolet absorbance at 280 nm (UV280; estimation for lignin content) dissolved in the recirculated water during the hot disintegration of the TMP pulp (carbohydrates were not dissolved). The results of this study suggest that thermophilic anaerobic treatment could be feasible at least as a part of an internal purification system to close the water circuit in the TMP process.
7
Kazymov, Dmitriy Sergeyevich, Lyudmila Gertsevna Makhotina, Андрей Борисович Nikandrov, Anton Gennad'yevich Kuznetsov, and Эдуард Львович Akim. "FEATURES OF LARIX SIBIRICA LEDEB WOOD PROCESSING INTO HIGH YIELD FIBROUS SEMI-FINISHED PRODUCTS." chemistry of plant raw material, no. 1 (March 16, 2021): 317–25. http://dx.doi.org/10.14258/jcprm.2021018472.
Повний текст джерелаАнотація:
About 40 % of the forest area in the Russian Federation is occupied by larch trees growing in the southern regions of Eastern Siberia and the Far East, where existing and reconstructed woodworking enterprises are located. In this regard, the use of larch wood in the production of fibrous semi-finished products is an urgent task for the Russian forest complex. As is known, larch wood contains a large number of extractive substances that have a significant impact on the process of its deep chemical processing. Therefore, it can be assumed that the production of wood (mechanical) pulp from larch wood, in particular chemical-thermomechanical pulp (CTMP), will be very effective, but with its own specific features. In this paper, it is proposed to modify the technology by using enzymes – protein catalysts of various reactions. The purpose of this study is to determine the potential of using larch wood enzymatic treatment in CTMP-technology, to evaluate the effect of enzymes on the physical and mechanical parameters of the fiber and the specific energy consumption during refining. Industrial samples of Larix sibirica Ledeb (Pinaceae) wood chips were used to obtain CTMP. Five commercially available enzymatic agents were used to treat wood chips. CTMP was obtained using laboratory equipment that simulates the industrial stages of production. Enzymatic treatment of larch wood has shown an improvement in the technological parameters of CTMP production, namely, a decrease in the specific energy consumption for refining and an increase in the quality of finished products.
8
Rejeb, Marouan, Ahmed Koubaa, Fayez Elleuch, François Godard, Sébastien Migneault, Besma Bouslimi, Mohamed Khlif, and Hatem Mrad. "Effects of Chromic Treatment on the Surface Properties of Polypropylene (PP) Wood Composites." Coatings 11, no. 7 (July 15, 2021): 851. http://dx.doi.org/10.3390/coatings11070851.
Повний текст джерелаАнотація:
The moisture sensitivity of wood–polymer composites (WPCs) is mainly related to their hydrophilic wood components. Coatings are among the alternatives that improve the dimensional stability of these composites. However, the adhesion of most coatings to the WPC surface is generally poor. Thus, chemical and/or mechanical treatments should be applied to the WPC surface to improve the coating adhesion. Therefore, the main objective of this study was to improve the adhesion coating of polypropylene (PP) WPCs through a chromic treatment. PP was reinforced by three different pulp fibers (kraft, thermomechanical (TMP), and chemothermomechanical (CTMP)) at three fiber contents (50, 60, and 70% w/w). A chromic treatment was applied to the PP-based WPCs to activate the surface of the composites and alter their roughness parameters, creating a higher interfacial zone that improved the bonding of the epoxy coating to the surface of the PP composites. The chromic treatment increased the roughness of the surface. An increase in profile and surface parameters was observed after treatment. This treatment modified the chemical composition of the surface by creating polar carbon–oxygen groups and increasing the carbonyl and hydroxyl indexes.
9
Bicho, Paul, Elmer Portillo, Bernard Yuen, Dongbo Yan, and Doug G. Pitt. "Effects of precommercial thinning on the forest value chain in northwestern New Brunswick: Part 5 – Kraft and Thermomechanical pulping and pulp quality." Forestry Chronicle 89, no. 04 (August 2013): 490–501. http://dx.doi.org/10.5558/tfc2013-090.
Повний текст джерелаАнотація:
Forty-eight years after application, three nominal precommercial thinning (PCT) spacings of 4 ft (1.2 m), 6 ft (1.8 m) and 8 ft (2.4 m) were compared to an unthinned control in six replicate, balsam fir (Abies balsamea [L.] Mill.)-dominated stands. Following the clearcut harvest of three of these replicates in 2008, chips produced from sawmilling trials (slab-wood) and from the top logs of the sampled trees (top-log) were kraft and thermomechanically (TMP) pulped. In general, top-log chips took longer to kraft pulp, had lower yields, and produced pulps with shorter, finer fibres than the corresponding slab-wood chips, across all PCT treatment levels. The main effects of PCT on pulping occurred with slab-wood chips and not top-log chips. While end-product quality in either kraft or TMP production was generally unaffected by wood from the range of thinnings tested, slight reductions in slab-wood chip density and H-factor suggest that kraft pulping productivity may be reduced by 1.8% with furnish from thinned stands. While these losses could be offset somewhat by lower chip consumption, the economic benefits for a kraft mill are marginal at best, and sharing of fiscal gains across the fibre value chain needs to be explored. Specific refining energy required in TMP production was, however, reduced by 4% with furnish from thinned stands. These results suggest that value-chain optimization is ultimately dependent on the segregation of fibre from different sources, including within-tree and among silvicultural treatments and sites.
10
Pichon, M., J. Rouger, and E. Junet. "Anaerobic Treatment of Sulphur-Containing Effluents." Water Science and Technology 20, no. 1 (January 1, 1988): 133–41. http://dx.doi.org/10.2166/wst.1988.0016.
Повний текст джерелаАнотація:
A new method of defibring wood chips and producing chemi-thermomechanical pulp with significant capital and energy savings has been developed. The pollution load of bleached CTMP effluent varied between 40-60 kg/t for BOD5 and 120-210 kg/t for COD. The process includes a sulphite stage and the effluent contains sulphur compounds which are toxic to methanogenic bacteria. Studies have been conducted on anaerobic fixed bed reactors with upflow or downflow feed modes. It is necessary to progressively acclimate bacteria to increasing concentrations of sulphur compounds. Permanent functioning of reactors is possible with COD/S ratios near 10-12 where propionate concentrations are increasing. Upflow reactors are more efficient than downflow reactors, with a maximum loading rate of 3.5 kg COD/m3.day corresponding to 800 mg/l as S. With hybrid sludge bed/fixed bed reactors it is possible to enhance anaerobic treatment efficiency. A COD loading rate of 4.7 kg/m3.day can be maintained with a residence time of 2 days and a pollution load removal efficiency of 45% for COD (55% with complementary oxidation) and 70% for BOD5. The economics of effluent treatment give an investment cost of about 20 US$/ADt for the activated sludge process and 12.5 US$/ADt for anaerobic fixed bed treatment.
11
Puke, Maris, Daniela Godina, Prans Brazdausks, Janis Rizikovs, and Velta Fridrihsone. "Thermomechanical and Alkaline Peroxide Mechanical Pulping of Lignocellulose Residue Obtained from the 2-Furaldehyde Production Process." Materials 15, no. 17 (August 25, 2022): 5872. http://dx.doi.org/10.3390/ma15175872.
Повний текст джерелаАнотація:
The necessity for the reduction in greenhouse gas emissions, the growing demand for the improvement of biorefinery technologies, and the development of new biorefining concepts oblige us as a society, and particularly us, as scientists, to develop novel biorefinery approaches. The purpose of this study is to thoroughly evaluate the leftover lignocellulosic (LC) biomass obtained after the manufacture of 2-furaldehyde, with the intention of further valorizing this resource. This study demonstrates that by using thermomechanical and alkaline peroxide mechanical pulping techniques, birch wood chips can be used in the new biorefinery processing chain for the production of 2-furaraldehyde, acetic acid, and cellulose pulp. In addition, the obtained lignocellulosic residue is also characterized. To produce a lignocellulosic material without pentoses and with the greatest amount of cellulose fiber preserved for future use, a novel bench-scale reactor technology is used. Studies were conducted utilizing orthophosphoric acid as a catalyst to deacetylate and dehydrate pentose monosaccharides found in birch wood, converting them to 2-furaldehyde and acetic acid. The results showed that, with the least amount of admixtures, the yields of the initial feedstock’s oven-dried mass (o.d.m.) of 2-furaldehyde, acetic acid, and lignocellulose residue ranged from 0.04 to 10.84%, 0.51 to 6.50%, and 68.13 to 98.07%, respectively, depending on the pretreatment conditions utilized. The ideal 2-furaldehyde production conditions with reference to the purity and usability of cellulose in residual lignocellulosic material were also discovered through experimental testing. The experiment that produced the best results in terms of 2-furaldehyde yield and purity of residual lignocellulose used a catalyst concentration of 70%, a catalyst quantity of 4%, a reaction temperature of 175 °C, and a treatment period of 60 min. It was possible to create pulp with a tensile index similar to standard printing paper by mechanically pulping the necessary LC residue with alkaline peroxide, proving that stepwise 2-furaldehyde production may be carried out with subsequent pulping to provide a variety of value-added goods.
12
Lloyd, John A., and Karl D. Murton. "Preparation of prehydrolysis-TMPs with different severity factors and analysis of the pulps and byproducts." Holzforschung 70, no. 11 (November 1, 2016): 1003–13. http://dx.doi.org/10.1515/hf-2015-0216.
Повний текст джерелаАнотація:
Abstract Thermomechanical pulps (TMPs) were prepared from Pinus radiata D. Don wood chips at pilot scale with application of different preheating severities. The hydrolysis products were separated at the compression screw feeding of the prehydrolysed chips into the refiner. Prehydrolysis of chips with steam at severity factor (SF) 3.5 reduced the refining energy (at 200 CSF freeness) by 36% when compared with the TMP control; however, the pulp quality was unacceptable. In contrast, pulps produced by SF 3.1 at 155°C have physical properties similar to the TMP control, but the energy saving is only 12%. Prehydrolysis darkens wood fibres making pulps unsuitable for printing and writing papers. However, it was demonstrated that the brightness may be recovered via conventional alkaline peroxide brightening. Pulp yield is lower but this disadvantage is offset by the availability of a pressate flow rich in hemicelluloses and hemicelluloses derived sugars in high concentrations that has good potential for conversion to new products. Impregnation of chips with citric acid (CA) during normal TMP processing was also investigated. Although refining energy was lower with CA treatment, the amount of extracted hemicelluloses was too small to be commercially useful. The prehydrolysis-TMP process may be of interest to financially constrained TMP mills provided that: (1) the process configuration is suitable for retrofitting an extended preheating stage with compression screw and (2) the extracted hemicelluloses can be converted to products of higher value than TMP.
13
Tanase, Mihaela, Per Stenius, Lars Johansson, Jan Hill, and Christer Sandberg. "Mass balance of lipophilic extractives around impressafiner in mill and pilot scale." Nordic Pulp & Paper Research Journal 25, no. 2 (May 1, 2010): 162–69. http://dx.doi.org/10.3183/npprj-2010-25-02-p162-169.
Повний текст джерелаАнотація:
Abstract Removal of extractives from the pulp furnish is of great importance for the improvement of paper machine efficiency and also for reducing the energy consumption during the thermomechanical pulp refining process. Extractives can exist in many different forms in the process water; as colloidal particles, dissolved or attached to fines and fibres. It is therefore important to know in which form they exist in order to fully understand their behaviour. In this paper, we report on an evaluation of the removal of extractives released from chips of different raw materials pre-treated in an Impressafiner, in pilot and in mill scale. In pilot trial the raw materials used were loblolly pine and white spruce and in the mil scale trial the raw material used was norway spruce. The colloidal stability of extractives present in the pressate water from the Impressafiner and their flocculation behaviour by cationic polymers (CPAM and Poly-DADMAC) under different conditions was also investigated. Calculations of mass balances around an Impressafiner showed that it was possible to remove up to 40% of extractives before the refining process. The reduction in total extractives content was mainly due to released resin acids while fatty acids, triglycerides, steryl esters and sterols to a large extent remained in the wood chips after pre-treatment. The removal of extractives from pine was four times higher than from spruce chips. The results can be explained in terms of the extractive composition in the raw material and the morphological differences in the wood structure.
14
Puke, Maris, Daniela Godina, Prans Brazdausks, and Janis Rizhikovs. "Study of a Novel Biorefining Method for Obtaining 2-Furaldehyde, Acetic Acid and Pulp from Birch Wood." Materials Science Forum 1071 (October 18, 2022): 204–11. http://dx.doi.org/10.4028/p-j8yji8.
Повний текст джерелаАнотація:
Necessity for reduction of greenhouse gases emissions, the growing demand for improvement of biorefinery technologies and the development of new biorefining concepts, oblige us as a society, mainly scientists, to develop novel biorefinery approaches. The aim of this research was to comprehensively characterize lignocellulosic biomass that was obtained after 2-furaldehyde production, in terms of further valorization of this resource. This research shows that birch wood chips can be used in the new biorefinery processing chain for production of 2-furaldehyde, acetic acid and subsequent cellulose pulp obtaining, using thermomechanical and alkaline peroxide mechanical pulping process. In addition, obtained lignocellulosic residue was also characterized. Unique bench-scale reactor system was used to obtain a lignocellulosic material without pentoses and with maximum preservation of cellulose fiber for further use. Studies on the deacetylation and dehydration of birch wood hemicelluloses of pentose monosaccharides to 2-furaldehyde and acetic acid using orthophosphoric acid as a catalyst were carried out. Results showed that depending on the used pretreatment conditions the 2-furaldehyde yield was from 0.04 to 10.84 % o.d.m., the acetic acid yield was from 0.51 to 6.50 % o.d.m. and the lignocellulose residue yield was from 68.13 to 98.07 % o.d.m. with minimal content of admixtures. In addition, experimentally the optimal 2-furaldehyde production conditions regarding to purity and usability of cellulose in leftover of lignocellulosic material were developed. Best results in terms of both 2-furaldehyde yield and purity of residual lignocellulose were obtained in experiment where catalyst concentration was 70%, catalyst amount 4 wt.%, reaction temperature 175 °C and treatment time 60 min. By performing alkaline peroxide mechanical pulping of the relevant LC residue, it was possible to obtain pulp with tensile index comparable to standard printing paper, indicating that it is possible to perform stepwise 2-furaldehyde production with subsequent pulping to obtain various value added products.
15
Puke, Maris, Daniela Godina, Mikelis Kirpluks, Prans Brazdausks, and Janis Rizikovs. "Characterization of Birch Wood Residue after 2-Furaldehyde Obtaining, for Further Integration in Biorefinery Processing." Polymers 13, no. 24 (December 13, 2021): 4366. http://dx.doi.org/10.3390/polym13244366.
Повний текст джерелаАнотація:
Latvia is a large manufacturer of plywood in Eastern Europe, with an annual production of 250,000 m3. In Latvia’s climatic conditions, birch (Betula pendula) is the main tree species that is mainly used for plywood production. A significant part of the processed wood makes up residues like veneer shorts, cores, and cut-offs (up to 30%), which have a high potential for value-added products. The aim of this research was to comprehensively characterize lignocellulosic (LC) biomass that was obtained after 2-furaldehyde production in terms of further valorization of this resource. The polymeric cellulose-enriched material can be used in the new biorefinery concept for the production of 2-furaldehyde, acetic acid, cellulose pulp, thermomechanical (TMP) and an alkaline peroxide mechanical (APMP) pulping process. In addition, we experimentally developed the best 2-furaldehyde production conditions to optimize the purity and usability of cellulose in the leftovers of the LC material. The best experimental results in terms of both 2-furaldehyde yield and the purity of residual lignocellulose were obtained if the catalyst concentration was 70%, the catalyst amount was 4 wt.%, the reaction temperature was 175 °C,and the treatment time was 60 min. After process optimization with DesignExpert11, we concluded that the best conditions for maximal glucose content (as cellulose fibers) was a catalyst concentration of 85%, a catalyst amount of 5 wt.%, a temperature of 164 °C, and a treatment time of 52 min.
16
Zasadowski, Dariusz, Anders Strand, Anna Sundberg, Håkan Edlund, and Magnus Norgren. "Selective purification of bleached spruce TMP process water by induced air flotation (IAF)." Holzforschung 68, no. 2 (February 1, 2014): 157–65. http://dx.doi.org/10.1515/hf-2013-0045.
Повний текст джерелаАнотація:
Abstract The environmentally benign closure of water systems in paper mills leads to the problem of accumulation of dissolved and colloidal wood substances (DCS) in process water. Notably, pitch affects the pulp and paper production negatively and increases the demand for additional treatment of the process water. In the present article, the purification of thermomechanical pulping process water from the alkaline peroxide bleaching stage has been investigated, with the induced air flotation (IAF) in focus. The following parameters were considered concerning the IAF efficiency to remove detrimental substances: concentration of cationic foaming agent, pH value, calcium concentration, and temperature. The amounts and characteristics of residual DCS were determined by gas chromatography and turbidity measurements. Residual concentrations of the foaming agent dodecyltrimetylammonium chloride were determined by electrospray ionization mass spectrometry. Up to 90% of pitch was removed, whereas hemicelluloses, which are important in preventing pitch problems, remained in the waters. Up to 70% of the pectic acids accounted for the high cationic demand of the process waters were removed by optimization of the IAF parameters. The presented separation process gives new opportunities to a selective purification of the process waters.