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Today, the paper industry is faced with a global deficiency of raw wood materials, so alternative sources of virgin cellulose fibres are playing an important role in paper production. Agricultural countries produce large quantities of crop farming by-products such as straw, which is an interesting alternative raw material for cellulose fibres. Straw is used in many industries because of its numerous advantages: animal food industry, biofuel industry, construction industry and as artistic material. The potential use of straw production residues is of great importance in paper and printing industry. The focus of this research is on triticale straw, which was used as a non-wood fibre source for paper production. Namely, triticale straw was converted into semi-chemical pulp and was combined with recycled wood pulp in order to produce alternative laboratory papers. The usability of this kind of laboratory papers in printing industry was analysed based on line reproduction quality. This research evaluated and analysed line reproduction quality based on four line attributes: width, blurriness and raggedness. The results of this research proved that triticale pulp in laboratory papers has equal influence on line printing quality as the recycled wood pulp.

Ionic liquids (IL) of 1-butyl-3-methylimidazolium chloride (BmimCl) homogeneously mixed with bleached kraft pulp (BKP) were used to investigate the change of paper properties and refining performance under the general conditions. Fiber morphology and paper strength were determined by fiber analyzer and paper physical property tester. The surface morphology and chemical properties of fiber was also performed by scanning electron microscope (SEM), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results indicated the optimized conditions of BmimCl pretreatment were BmimCl dosage of 1.5 mL/g, the time and temperature of 30 min and 80 °C, respectively. The physical properties of paper and internal bond strength of fiber was improved by BmimCl pretreatment. BmimCl pretreatment facilitated swelling and fibrillation of fiber, increased the crystalline index of fiber and decreased the lignin and extractives on the surface of fiber, which leading to improve fiber strength and tensile strength. For the same refining energy input, saving the maximum refining energy consumption was 14.0 % after BmimCl pretreatment, which is beneficial to improve the application of ionic liquid in pulp and papermaking.

The objective of this study was to check the potential of crude xylano-pectinolytic enzymes in bleaching of rice straw pulp, in order to reduce the toxic waste load for managing the environmental pollution. The xylano-pectinolytic enzymatic bleaching step for delignification was found to be most effective at pulp consistency 1:10 g/ml, xylanase:pectinase dose of 9:4 IU/ml, pH 8.5 and treatment time 180 min at temperature of 55 °C, and resulted in lowering of kappa number of the rice straw pulp by 15.29%. In subsequent bleaching stages, this enzymatic pre-bleaching treatment also resulted in 30% reduction of active chlorine dioxide dose without any loss of optical properties. Significant improvement in various physical properties of the enzymes treated pulp, tear index (15.43%), breaking length (11.11%), double fold number (25.92%), burst index (9.88%) and viscosity (13.63%), and Gurley porosity (39.86%) was also noticed. This approach resulted in reduction of BOD and COD values by 21.07% and 26.57%, respectively. This is the first study on the use of crude xylano-pectinolytic enzymes for bio-bleaching of rice straw pulp.

The main environmental risks in the area of landfills are considered, all aspects of their technological reclamation using waste from the Baikal PPM are discussed. The data on the creation of soil and grounds using lignin-destroying microbiological preparations are presented. The final stage of the remediation of the Solzan landfill is the creation of cadastral maps 8, 9, 10 modern forest nurseries on the site, protected by flood and mudflow protection structures.

Maturity of vermicomposted end products obtained from citronella bagasse (CB) and a mixture of citronella bagasse and paper mill sludge (CB + PMS) was determined employing the epigeic earthworm species Eisenia fetida. Two of the primary biological indicators—enzyme assay and germination index—were used for evaluation of vermicompost maturity. The enzyme assay includes the changes in dehydrogenase and urease activities in the final products. The test for germination index was performed on two economically important plant species Abelmoschus esculentus and Solanum melongena. The results revealed a significant increase in dehydrogenase and urease activities in the vermicompost samples over the raw materials and traditional compost. The enhancement was recorded 215.63–225.63% in dehydrogenase and 149.89–249.31% for urease in the end products obtained after 45 days of experimental trials. Further, the higher values of germination index in the vermicompost treatments as against the control confirm the suitability and stability of the vermicomposted final products.

Effects of enzymatic modification were evaluated in bleached Eucalyptus kraft and sulfite cellulosic pulps, separately, to improve key tissue paper properties and design new Eucalyptus fiber applications. Different cellulase dosages (0.01 mg and 0.1 mg of enzyme/g of pulp) and reaction times (30 min and 60 min) were used to modify the fibers and replace the traditional mechanical based refining or beating process. The results showed that for enzymatic modified kraft and sulfite pulps, the softness properties were improved by 1 and 2 units, respectively, for each unit of decreased strength properties. To achieve a balance between the tissue properties, the different fiber pulp furnishes that contained 80% of the enzymatically treated kraft pulp and 20% of the sulfite pulp with and without enzymatic treatment, were studied. Overall, the structures made with these mixtures presented softness properties in the commercial range (57.8 to 74.4), improved absorption properties (107 mm to 120 mm of capillary rise), and good strength properties (13.0 to 17.7 N.m/g). This study was conducted in order to adjust the fiber furnishes according to industrial tissue standards, using one Eucalyptus fiber type providing strength and another providing softness.

The applicability of the developed binary system of synthetic compounds in coating paste, consisting of urea-formaldehyde oligomer (2 pts. wt. to the coating paste weight) and latex (16 pts. wt.), is found. It replaces the generally used complex of natural compounds, such as modified starch (3 pts. wt.), Na-CMC (2 pts. wt.), and casein glue (1 pts. wt.), in the presence of latex (16–32 pts. wt.). The properties of the coating paste samples met the standards, as evidenced by the viscosity according to the viscometer VZ-4 (13–17 s), the content of dry substances (50–54 %) and pH (9.0–10.5). The proposed urea-formaldehyde oligomer is combined with the present components and, as compared to natural compounds, does not increase the viscosity of the coating paste, has a high cohesive force, participating in the binding of pigment particles with one another, has the necessary adhesive capacity for ensuring a stable bond of the applied coating layer with the surface of paper and cardboard, does not prevent the uniform distribution of pigment particles on the base surface, and gives stability to the coating paste. These phenomena can be explained by the supplementary presence of positively charged nitrogen-containing groups (amine and amide) in the urea formaldehyde oligomer. The latter contribute to the enhancement of cohesive and adhesive interactions in coating pastes and coatings composed of them. Assessment of a section of the coated paper (cardboard) showed that one part of the binder adjoins the base (paper, cardboard) penetrating into its pores and capillaries, the other surrounds the pigment particles, and the third occupies (completely or partially) the spaces between the particles. An increase in the surface resistance to plucking and breaking length by 6.0–8.5 and 15–20 %, respectively, is shown on the samples of light-coated newsprint and polygraphic cardboard. This allows considering the urea-formaldehyde oligomer as an alternative to natural compounds. Herewith, whiteness (85–87 %) and smoothness (250–265 s) meet the requirements. Changing the formulation of the coating paste is economically justified, since material costs for the production of coated paper and cardboard products are reduced by 1–2 %.For citation: Chornaya N.V., Bogdanovich N.I., Karpova S.V., Misyurov O.A. Application of Urea-Formaldehyde Oligomer for Quality Improvment of Paper and Cardboard Products. Lesnoy Zhurnal [Russian Forestry Journal], 2020, no. 6, pp. 182–193. DOI: 10.37482/0536-1036-2020-6-182-193

Recently, the interest in active packaging utilization has increased with population growth, food demand and new consumer trend like food delivery services. This new system, however, requires the use of additives to extend the food product quality and safety as well as in maintaining the shelf-life. This study was to prepare the antimicrobial paper from I. cylindrica coated anionic nanocellulose crosslinked cationic to create a system with the ability to actively control microbe growth in the packaging materials. The process involved pulping of I. cylindrica using semi-chemical and soda chemical method. The antimicrobial paper was prepared by printing the pulp suspension in 60 g/m2 grammage in mold followed by the spray of anionic nanocellulose and subsequent soaking of the paper in cationic solution. The results showed the I. cylindrica paper coated anionic nanocellulose crosslinked with H+ and Al3+ cations were successfully produced. The paper produced was also observed to have antimicrobial activity against Gram-negative of E. coli and S. typhi as well as Gram-positive of S. aureus and B. subtilis bacteria. Furthermore, the best coating method was found on antimicrobial paper coated anionic nanocellulose crosslinked Al3+ as evidenced by smoother and compact surface structure.

The aim of the study is to analyze the results of ecological monitoring of the aquatic biota of the river. Vychegda and their practical use on the example of water-intensive pulp and paper production. The availability of the results of our own studies of the actual values of the monthly biomasses of phytoplankton and zooplankton made it possible to assess the difference between the use of actual and literary data. According to actual data, the damage from the death of phytoplankton is 4.5 times lower, and of zooplankton – 97 times lower, compared with the results of calculations using literature data.

The pulp and paper industry produces a diverse range of side-streams from multi-stage processes, but these remain underutilized despite their high potential for use as biofuels. This study investigated acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum DSM 1731 from the side-streams of three different stages of the pulp and paper manufacturing process (PI, PII, and PIII). Biomass specimens with and without water washing were pretreated with 0.2% H2SO4 at 180 °C for 10 min, followed by enzymatic hydrolysis, to obtain fermentable sugars. The results showed that the produced ABE solvent concentrations were 12.8 g/L, 5.2 g/L, and 6.3 g/L from PI, PII, and PIII, respectively. The butanol yields of PI, PII, and PIII were 0.25, 0.18, and 0.19 g/g sugars, respectively. Among the tested side-streams, PI was shown to have potential as a feedstock for butanol production without prewashing prior to dilute acid pretreatment, enzymatic hydrolysis, and microbial fermentation.

3-Aminopropyl-trimethoxysilane was introduced into bis-triazinyl amino-stilbene through the condensation reaction to obtain fluorescent whitening agents (FWAs) having excellent photo-stability. Tetraethoxysilane was hydrolyzed and combined with FWAs through in situ polymerization to obtain nanosilica-loaded yellowing inhibitors (SiO2–FWAs). Ultraviolet (UV) spectroscopy showed that the ratios of the trans-isomer structure in FWAs after 3 h of UV irradiation was 5.41 times higher than those of the cis-isomer. Moreover, the absorption intensity in the UV region was increased distinctly after nano-silica loading. Fluorescence spectroscopy revealed that the fluorescence of SiO2–FWAs was more intense than that of FWAs. In addition, the fluorescence quantum yield of SiO2–FWAs reached 0.416, whereas that of the default FWAs was only 0.279. UV-aging test results showed that SiO2–FWAs can improve the initial whiteness and anti-yellowing performance of paper made from high-yield pulp (HYP). These results indicated that the as-prepared SiO2–FWAs not only exhibited more excellent UV absorption and fluorescence emission properties, but it also exerted better whitening and anti-yellowing effects on high-yield pulp paper than the default FWAs. The enhanced performance of SiO2–FWAs can be ascribed to the synergy between the excellent UV-scattering effect of nanosilica and the fluorescent whitening property of FWAs.

A paper-based membraneless direct hydrogen peroxide fuel cell was developed and tested under different potassium hydroxide concentrations (1 to 7 mol lt-1, stepping by 2), different hydrogen peroxide concentrations (1, 2, 3 mol lt-1) and different temperatures (20, 30, 40oC). Moreover, the developed fuel cell was studied for stability under stopped and continuous flow conditions. From the experiments, it was found that the maximum power density of 6.79 mW cm-2 and the maximum open circuit voltage of 0.87 V at 40oC were obtained when the anode solution consisted 2 mol lt-1 H2O2 and 5 mol lt-1 potassium hydroxide and cathode solution consisted 2 mol lt-1 sulfuric acid and 2 mol lt-1 hydrogen peroxide. It was found that if the reactants were supplied constantly into the fuel cell, a current density of 3.12 mA cm-2 was obtained. The developed fuel cell produced energy for 91 minutes when the reactant flow was stopped.

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., U ovom je radu istražena mogućnost uporabe biljaka Rhododendron luteum i Rhododendron ponticum kao sirovine za proizvodnju celuloze i papira. Za svaki uzorak provedeno je 12 različitih ispitivanja kuhanja s natrijevim borhidridom (NaBH4), a celuloza je proizvedena kraft postupkom. Za svako ispitivanje određena su svojstva celuloze poput prinosa, kappa broja i viskoznosti, te fizička svojstva kao što su duljina lomljenja i indeks pucanja papira. Osim toga, ispitani su učinci aktivne lužine i NaBH4 na svojstva celuloze i papira. Optimalni uvjeti kuhanja postignuti su upotrebom 18 % aktivne lužine za eksperimentalno kuhanje bez NaBH4 i upotrebom 0,5 % NaBH4 i 18 % aktivne lužine za eksperimentalno kuhanje s dodatkom NaBH4. U proizvodnji celuloze iz biljke R. luteum s dodatkom NaBH4 utvrđeno je da prinos prosijavanja iznosi 43,4 %, da je kappa broj 40,1, a viskoznost 949 cm3/g, dok su vrijednosti za celulozu dobivenu iz biljke R. ponticum redom 41,9 %, 44,5 i 885 cm3/g. Prinos prosijavanja biljaka R. luteum i R. ponticum uz dodatak 5 % NaBH4 povećao se oko 2,8 % i 5,3 % u usporedbi s eksperimentalnim kuhanjem bez dodatka NaBH4. Nadalje, uz dodatak NaBH4 smanjuju se kappa brojevi, a viskoznosti se povećavaju. Fizička svojstva proizvedenih papira također se poboljšavaju dodavanjem NaBH4 tekućini za kuhanje. Iz dobivenih je rezultata utvrđeno da se biljke R. luteum i R. ponticum mogu upotrebljavati u proizvodnji celuloze i papira.

The work presented in this paper is focussed on study of structure and properties of coating layers based on natural pigments (ground calcium carbonate and clay) and butadiene acrylonitrile latex as binder in correlation with functional properties of the final coated paper. It is quantified the influence of binder content and pigment type on the structural and liquids penetration properties of coating layer. The obtained results confirm that by increasing of binder content in the coating formulations a reduced efficiency of light-scattering and increased roughness for coated surfaces is obtained. At the high binder amounts (over 15 pph), the coating layer porosity is reduced and as result a lower liquids penetration in the coated papers is obtained.

The search for non-wood fibers as alternative to the limited wood fiber resources is highly imperative in the pulp and paper-based industries. This is due to growing environmental concern as a result of excessive deforestation. This study aimed at investigating the pulp and paper potentials of pineapple crown (Ananas comosus), sandbox (Hura crepitans), pino macho (Pinus caribaea), elephant grass (Pennissetum purpureum) and teak (Tectona grandis) leaves. Chemical properties (holocellulose, cellulose, hemicellulose, ash contents, hot water and 1% NaOH solubilities) were determined using the relevant TAPPI test and chlorite methods, while the physical properties were determined after the pulping processes. Fourier transform-infrared spectroscopic (FT-IR) analyses of intrinsic functional groups of the paper sheets produced from the pulps of the waste plant leaves were determined. In addition, scanning electron microscope (SEM-EDX) analyses of the morphological characteristic and elemental compositions of the resulting hand sheet surfaces were also examined. P. caribaea has the highest lignin (80.22 ± 0.012%) and cellulose (72.30 ± 0.012%) contents with lowest 1% NaOH solubility (15.20 ± 0.05%) values. A .comosus has the highest hemicellulose (21.73 ± 0.1%) and moisture (75.00 ± 0.12%) contents with lowest ash values (5.01 ± 0.15%). The fibre lengths and the Runkel ratio of the resulting pulps were of the order, A. comosus > P. purpureum > P. caribaea > H. crepitans > T. grandis and A. comosus

The efficiency of xylano-pectinolytic enzymes, co-produced by a single microbial strain Bacillus pumilus, was analysed for the recycling of mixed office waste paper through deinking and compared with the alkaline chemical deinking method. Enzymes showed maximum deinking at pH 8.5, pulp consistency of 10%, xylanase-pectinase dose of 12 and 4 IU per gram pulp, respectively, after 120 min of deinking period, and temperature at 50 °C. A chemi-enzymatic approach was employed with xylano-pectinolytic enzymes and various concentrations of deinking chemicals, which showed that enzyme-treated mixed office waste pulp requires only 40% chemicals for deinking, in order to get the almost same level of various handsheets properties, as obtained by the chemical method with 100% chemicals. Similarly, the effluent load of BOD and COD contents was also decreased by 17.90 and 19.75%. This combinational approach of deinking significantly improved the various properties of the handsheets and resulted in gain of 7.5, 9.38, 6.33 and 11.65% in tear factor, burst factor, breaking length and viscosity of the handsheets, while the effective residual ink concentration analysis of deinked handsheets of mixed office waste paper showed deinking efficiency of 22.45%, which revealed the removal of ink particles during enzymatic deinking steps.

The present study was undertaken to know the effect of common mixed pulp and paper mill effluent discharge released from century pulp and paper mill Lalkuan, Nainital Uttarakhand on the blood morphology of Heteropneustes fossilis (Singhi). The various morphological changes were observed in the specimen, randomly collected with the help of cast net from (3 sites) different locations. The maximum changes were observed in the specimen collected from site 3 in compare to site 1 and 2 respectively. The formation of inclusion bodies, sickle cells, Cabot rings and ovalocytes were recorded along with nuclear fusion, membrane disruption and cell clumping of blood cells in the specimen collected from the site 3 (i.e. nearer to source of discharge) while in the specimen collected from site 2, the formation of tear drop cell, target cells, spherocytes and bi-nucleated cells were recorded along with the activity of cell clumping. The changes were found less in the specimen collected from site 1 in compare to the specimen of site 2 and 3 i.e. formation of ovalocytes, spherocytes and microcytes with the activity of membrane degeneration and agglutination in blood cells.

Considering that optical properties play a very important role in the printing industry, this research focused on analysing the optical properties (opacity, whiteness, brightness and yellowness) of laboratory made papers from recycled wood pulp, with the addition of different straw contents, coated with titanium dioxide white ink. Titanium dioxide white ink was applied on laboratory papers to achieve optical characteristics as those of commercial papers recommended by ISO 12647. All the coated laboratory papers presented whiteness within the recommendations of the standard. Almost all the coated papers made with the addition of straw pulp achieved satisfactory optical properties, especially those containing 10% and 20% straw pulp. Coated laboratory papers containing 10% and 20% wheat pulp were comparable to commercial paper and reached a similar value of brightness, while their opacity and yellowness values were even better than those of commercial paper. In order to preserve the natural appearance of papers made with the addition of straw pulp, it is possible to conduct selective white printing as background for high-quality printing.

With the increasing popularity of coated paper, it has been more widely used in printing, publishing, product packaging and commercial promotion. However, coated paper is prone to cracks after printing and folding which exposes to a white area which is referred to as fold cracking. This study investigated the coating properties of paper and coating factors influencing the fold cracking and aimed to provide guidance on how to reduce the problems of fold cracking. This paper mainly discusses the effects of pigment proportion, binder dosage, solids content, coating thickness and calendering pressure on fold cracking of coated paper after printing. Experiments show that when the coating consisted entirely of calcium carbonate, the degree of fold cracking is most serious. With the addition of kaolin, the fold cracking reduces. When the ratio of the number of parts of calcium carbonate to kaolin is 25/75, the area of fold cracking reaches its minimum value of 10.28 %. With increasing solids content of the coating, the fold cracking decreases initially and then increases. When the solids content is 55 %, the fold cracking reaches a minimum. Increased latex content reduced coating thickness and an increase in calendering pressure gradually reduce the degree of fold cracking.

This study aimed to evaluate eggshell wastes, which have the potential to turn into high value-added products in paper industry. Membrane-removed eggshell wastes were subjected to certain processes of washing, drying, grinding, and sieving. The final product of eggshell calcium carbonate (ECC) was used in office paper production as filler, and its possible effect on physical and optical properties of papers was investigated. Mixed office wastes were turned pulp using as raw material of office paper production. Moreover, the effects of ECC was compared with the use of industrial calcium carbonates of ground (GCC) and precipitated (PCC) forms as filler. Breaking lengths of the papers were shown to reduce up to 65.2, 76.6, and 64.1% by a 30% usage of GCC, PCC, and ECC fillers, respectively. PCC and GCC were more effective in improved optical properties of papers than ECC. The brightness values were measured to be 96.8, 98.4, and 93.1 ISO% with a 30% dosage of GCC, PCC, and ECC fillers, respectively. These results suggested that ECC can be used as filler in paper industry.

Absorption capacity is a key feature of toilet tissue papers. Several parameters can affect their final absorption capacities, such as pulp composition, stock preparation, number of sheets, additives, bulk, grammage, and converting process parameters, such as the embossing operation. In this work, the absorption capacities of four different 2-ply industrial toilet tissue papers, as well as the respective base papers from the mother-reel was compared using the immersion method according to ISO 12625-8 (2010). Previously, these samples were characterized in terms of morphology, grammage, thickness, and bulk. It was concluded that the embossing operation noticeably increased the thickness and bulk of toilet tissue paper. Furthermore, it was also verified that among the various toilet tissue paper samples there was not a noticeable variation in the time of water absorption because the samples revealed similar morphology and porosity. However, it was found that the bulk increased more than 150%, resulting in an increase of water absorption capacity over 60%.

Paper-based packaging is widely employed in industries ranging from food to beverages to pharmaceuticals because of its attractive advantages of biodegradability, recyclability, good strength, low cost, and lightweight. However, paper products usually have poor water barrier resistance properties because of paper and fibers porous microstructure. In this study, an ecofriendly water-resistant (hydrophobic) oil from biological origin, namely, palm kernel oil (PKO) was used to coat paper by using a facile and cost-effective dip-casting approach. PKO formulation was prepared by mixing with a solvent and furfuryl alcohol (FA). The water resistance, structural properties, and thermal and mechanical properties of the coated papers obtained under different processing conditions were reported and compared to understand the performance of coated paper. Contact angle (CA), Fourier transform infrared (FTIR), and thermal gravimetry (TGA) were used for analysis and characterization of coated papers. Data from contact angle measurements showed that the PKO formulation could considerably improve the liquid water barrier property of the paper, with a measured water contact angle (CA) of ∼120° and reduce the water vapor transmission rate (WVTR) by 22%. This novel, green, low-cost, and water-resistant paper coating made with biological and biodegradable oil is a potential candidate for replacing petroleum-based coatings used in a broad range of applications and will also be able to make an additional full use of the palm kernel oil.

The study is a first investigation of the feasibility to preserve recycled fillers (e.g. calcium carbonate, kaolin) from deinking paper sludge for newspaper production using an alternative approach respect to the actual methods. Deinking paper sludge was incinerated at 575 °C. The thermal stability of the incinerated sludge (ash) was evaluated by infrared analysis. Subsequently, the resulting ash was bleached by sodium dithionite. The particle size of the ashes was analysed by laser diffraction. The effect of recycled fillers on recycled paper pulp, after blending, was evaluated by the analysis of the physical and optical properties of the obtained paper sheets. Analysis showed the conservation of the calcium carbonate and other fillers’ molecular structure, both after incineration of the sludge and after bleaching. The dithionite treatment of the ashes resulted in ISO brightness levels of more than 70. The brightness was stable over one month. Paper sheets made by blending the bleached ashes with recycled paper showed an improvement of brightness and opacity but a decrease in terms of porosity and breaking length compared to paper sheets made without any filler. The proposed method still requires further studies to evaluate the economical application but offers an opportunity for the recycling of inorganic materials and valorisation of the sludge.

Based on publications related to the use of micro- and nanofibrillated cellulose (MNFC) in papermaking applications, three sets of parameters (intrinsic and extrinsic variables, furnish composition, and degree of dispersion) were proposed. This holistic approach intends to facilitate understanding and manipulation of the main factors describing the colloidal behavior in systems comprising of MNFC, pulp fibers, and additives, which directly impact paper product performance. A preliminary techno-economic assessment showed that cost reductions driven by the addition of MNFC in paper furnishes could be as high as USD 149 per ton of fiber (up to 20% fiber reduction without adverse effects on paper’s strength) depending on the cost of papermaking fibers. It was also determined that better performance in terms of strength development associated with a higher degree of MNFC fibrillation offset its high manufacturing cost. However, there is a limit from which additional fibrillation does not seem to contribute to further strength gains that can justify the increasing production cost. Further research is needed regarding raw materials, degree of fibrillation, and combination with polyelectrolytes to further explore the potential of MNFC for the reduction of weight of paper products.

The paper presents the results of the analysis on measured parameters of harmonics at the node of the high-voltage network. The measurements were made at the node connecting the pulp-and-paper mill to the 220 kV supply network. This load is nonlinear and has a large capacity. Particular attention is paid to the distributions of the current and voltage harmonics. The paper clearly shows probabilistic properties of the measured parameters of harmonics

The thriving development of the paper industry leaves behind a great amount of pulp and paper mill sludge (PPMS), which constitutes a considerable source of pollution. Experts estimate that...

The present study investigated the Ethiopian sugarcane bagasse during its delignification via the sulfur-free soda pulping process and bleaching by the single-stage hydrogen peroxide process. The multilevel categoric experimental design was used to assess the effects of the three independent process variables (pulping temperature, NaOH concentration and time) on the pulp yield and kappa number, during the soda pulping process. The effect of the independent bleaching variables (bleaching temperature, time and H2O2 concentration) on the pulp yield, brightness and whiteness was assessed by using the response surface methodology (central composite experimental design). The soda pulps from the Ethiopian sugarcane bagasse were of varying yield and kappa number and hence were classified according to the sugarcane bagasse providing the highest pulp yield (pulp-SA) with 88.07% and that providing the lowest pulp yield (pulp-SB) with 85.17%. Their corresponding kappa numbers were 16.73 and 8.27, respectively. The brightness and whiteness for the pulp-SA were 62.02% and 84.43%, respectively, whereas for the pulp-SB, the corresponding values were 71.86% and 90.47%, respectively. The study further shows that the paper produced from the pulp-SA had higher mechanical properties. Thus, the promising valorization of the Ethiopian sugarcane bagasse for paper production using the adopted methodology, namely the soda pulping and single-stage hydrogen peroxide bleaching routes, is validated.

A series of industrial experimental tests on the freeze treatment of colloidal sludge lignin precipitates was carried out under natural conditions. Changes in the physical and chemical properties of the precipitates were studied. It is established that three fractions are formed following the freeze treatment of colloidal sludge lignin precipitates, including demineralized water (up to 25 %), mineralized water (up to 15 %) and a restructured colloidal precipitate (up to 60 %). The total volume of the precipitate is shown to decrease to 40 %. Freezing precipitation of colloidal lignin slurry of "the Baikal Pulp and Paper Mill" leads to a decrease in toxicity from the third to the fifth class of danger. On the basis of frozen sediments, the lignin sludge of OJSC Baikal Pulp and Paper Mill with the addition of other waste from the Baikal region, a fertile soil was obtained that corresponds to GOST R 54651-2011 "Organic fertilizers on the basis of sewage sludge. Specifications".

The study describes the preparation of pulp and nanocellulose from non-wood plant materials, as well as an improved properties of paper and cardboard for mass production. The pulps from wheat straw, kenaf and flax fibers were prepared by the environmentally friendly organosolv method—cooking in a solution of isobutanol or peracetic acid. The organosolv pulps used to prepare nanocellulose had traces of lignin and mineral substances. The process of hydrolysis of the investigated organosolv pulps was optimal when carried out under the following conditions: 43% sulfuric acid, temperature 60 °C, hydrolysis time 90 min and ultrasonic treatment 60 min. Using the methods of SEM, XRD, TEM, AFM and TGA, the structure and properties of organosolv pulps and nanocellulose were studied. The use of nanocellulose in bulk and on the surface of mass types of paper and cardboard—paper for corrugation, offset paper, recycled containerboard and cardboard for flat layers of corrugated cardboard were investigated. We established the positive effect of nanocellulose application on the physical and mechanical properties of paper and cardboard. Low consumption of nanocellulose allows production of the paper and cardboard with properties that meet the requirements to appropriate standards and replacement of synthetic reinforcing materials.

Introduction. Pulp and paper enterprises accumulate large volumes of industrial waste buried in special accumulation cells. In order to choose a technology for treating above-sludge waters, we need to monitor their composition, which depends on the history of cells’ filling and their subsequent use. Methods. In the course of the study, we applied inductively coupled plasma mass spectrometry (ICP-MS). Results. We determined the content of 72 chemical elements in above-sludge water of 11 cells at Baykalsk Pulp and Paper Mill and 4 open water flows near industrial waste landfills, and performed a cluster analysis of the sample composition. As a result, we revealed the peculiarities of water composition, related to the history of cell filling and subsequent pilot experiments. It has been found that the cells with non-disturbed sediments have cleaner water. Out of 16 chemical elements subject to limitation (Na, Al, P, S, Cl, K, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Mo, Cd, Pb), 11 elements exceed the limits established for wastewater discharged into water bodies within the ecological zones of the Baikal Natural Territory. Each cell is characterized by its own set of elements exceeding maximum allowable concentrations (MAC) and by the extent of such excess. Conclusion. Pilot experiments with cell sediments (joint grouting, drying, dewatering in press-filters) result in the disturbance of the “water/sediment” balance and increase the concentrations of most elements in above-sludge waters. The maximum amounts of elements (6–7) exceeding the MAC values are observed in water in the cells with disturbed sediments, water in the zone of ash slurry discharge, ash and sludge-lignin cells with industrial and household waste. When choosing a technology and procedures for treating above-sludge waters, it is necessary to take into account the specifics of their composition. Using the polluted water flow running into Lake Baikal during catastrophic floods in the summer of 2019 as an example, we show that it is possible to use multi-element ICP-MS analysis to search for sources of pollution from industrial facilities.

Enormous quantities of bagasse are being used as raw material in agro based large integrated pulp and paper mills. Anaerobic technology is an effective means of biodegradation of organic substance in wastewater and energy production of biogas that can be used as an alternative fuel. This study illustrates the effect of HRT on performance of lab scale hybrid upflow anaerobic sludge blanket (HUASB) reactor on treatment of pulp and paper mill bagasse wash water. The lab scale HUASB reactor was designed for an effective volume of 0.013 m3 with bio balls as packing media at the top of reactor and operated under mesophilic condition. After startup period, the reactor was operated with HRTs of 23.55, 15.98, 12.00, 10.03 and 7.97 h for the average influent COD concentrations of 2503.6 mg/L, 3918 mg/L, 5432 mg/L, 6608 mg/L and 7996 mg/L respectively. The results showed that the maximum COD removal efficiencies and TSS removal efficiencies were in the range of 68.60–92.19% and 89.56–94.66% respectively. The minimum and maximum biogas yield of 0.32 and 0.53 m3/kg CODa were obtained at influent concentration of 2503.6 mg/L and 7996 mg/L respectively.

Research is devoted to the problem of recycling waste of the Baikal Pulp and Paper Mill, whose activity has caused serious damage to the ecological environment of Lake Baikal and its environs. Grouting waste production is currently the most effective possible decision to the problem of pollutants, such as sludge-lignin and ash, in water objects and groundwater. The results on the grouting of liquid and solid waste from the Baikal Pulp and Paper Mill, represented by sludge lignin and ash, are presented. Cement, liquid glass, colloidal silica, ammonium persulfate, hydrogen peroxide were used as the main hardeners. Samples were formed by mixing the original waste with astringent. The strength in time, shrinkage, resistance to water were studied. Samples formed on the basis of colloidal silica solution have a maximum uniaxial compressive strength of 0.4 - 0.5 MPa, on the basis of liquid glass—0.2 - 0.3 MPa. Adding fine sand increases the strength by 1.5 - 1.7 times. Samples based on ammonium persulfate and hydrogen peroxide do not have sufficient strength. Adding fine quartz sand increases the strength up to 1.0 - 1.2 MPa.

The pulp and paper industry utilizes more biomass for stationary heat and power than any other industry in the United States. In total, pulp and paper mills in the US emit ∼150 million metric tons of CO2 each year, of which 77% is biogenic. Thus, the pulp and paper industry has significant potential to indirectly remove atmospheric CO2 through bioenergy with CO2 capture and storage (BECCS). In addition, avenues for CO2 utilization exist in pulp and paper processing. Here, we analyze the technical and economic potential of integrating carbon capture, utilization, and sequestration (CCUS) technologies at pulp and paper mills in the US through top-down, industry-wide screening and bottom-up, chemical process modeling techniques. We estimate costs of capturing and transporting CO2 from pulp and paper mills using post-combustion amine chemisorption in the year 2026 with application of the existing federal tax credit for carbon capture and sequestration (Section 45Q). Costs are highly dependent on scenario-specific details, such as waste heat or power generation at the mill, idling or stranded assets, and proximity to suitable geologic storage opportunities. Some CCS implementation scenarios produce significant economic returns for pulp and paper mills, indicating a near-term opportunity to accelerate CCS in the US. Finally, we qualitatively assess alternative techniques for CO2 capture through process innovation, and opportunities for CO2 utilization at pulp and paper mills.

The present research deals with multivariate regression modeling of heavy metals uptake by cultivated Eichhornia crassipes (water hyacinth: WH) in the wastewater of paper and pulp processing industry. The WH plants were grown in different treatments of wastewater of paper and pulp processing industry (25, 50, 75, and 100%), while the control experiment was performed using borewell water. The influence of pH and metal quantity in the wastewater of paper and pulp processing industry over effective metal accumulation (∆Y: mg kg− 1) by WH was statistically modeled. Results showed that the established models had high R2 (

An innovative approach for preparing hemp fibers from hemp hurds for use in tissue and towel grades of paper is described. Hemp hurds are a low value by-product of industrial hemp processing that are generally used for animal bed litter. Tissue paper was fabricated from hemp hurd fibers by following three pulping processes: autohydrolysis (hydrothermal), sodium carbonate-based defibration, and high yield kraft pulping, and benchmarked against hardwood pulp. To meet industrial standards, hardwood and hemp pulp fibers were mixed at a dry mass ratio of 75:25, from which tissue paper sheets were prepared. Desirable tissue paper properties, such as water absorption, burst resistance, softness, and tensile strength (dry and wet), were measured and compared. Characterization of morphological and chemical properties of tissue handsheets was conducted with SEM and time-of-flight-secondary ion mass spectrometry (ToF-SIMS). The combined kraft pulped hardwood and autohydrolyzed hemp pulp fibers displayed improvements in tensile index, burst resistance, and softness of tissue handsheets compared to only kraft hardwood pulp handsheets without adversely impacting water absorption. Hardwood fibers showed a sparse distribution of surface lignin compared to hemp fibers using the same defibration. This technology can lead to a variety of eco-friendly tissue paper products that are not only highly energy efficient, but avoid harsh chemical processing.

This study was carried out to evaluate the physical and thermal characteristics of briquettes made from a mixture of paper pulp and Mesua ferrea leaves. Paper pulp/ground Mesua ferrea leaves mixtur...

Wastewater recycling and sludge removal in the paper industry account for about 60 % of all process costs. New and environmentally friendly wastewater treatment techniques are, therefore, continually being developed. Cavitation exploitation is currently a well-investigated topic that is also interesting for the paper production industry. This study investigates efficiency of hydrodynamic cavitation alone and in combination with the addition of NaOH for the treatment of secondary pulp and paper mill sludge in order to enhance nutrient release. First, two laboratory-scale devices were tested: the blow-through and the rotating hydrodynamic cavitation generator. The latter set-up proved to be more efficient: therefore, further experiments were performed on its pilot-scale version. The results showed an increase of soluble chemical oxygen demand (CODs) by 514 mg/L, total nitrogen (Nt) by 17.4 mg/L, and total phosphorous (Pt) by 2.3 mg/L. To further increase nutrient release combination of cavitation and sludge sample alkalinization was tested. The addition of NaOH and 30 min cavitation of secondary sludge (500 L) significantly improved CODs and Nt release by 2400 mg/L and 120 mg/L, respectively. Microbiological photos revealed a definite disintegration of sludge flocks. According to our estimates, 1.9 kg of released CODs from alkaline pre-treated and cavitated sludge would cost only one euro.