Pulp Industry Research Articles

Oxidation Treatments Using Hydrogen Peroxide to Convert Paper-Grade Eucalyptus Kraft Pulp into Dissolving-Grade Pulp

Converting paper-grade bleached Kraft pulp into dissolving pulp using eco-friendly chemicals on-site at the mill is a challenge for the pulp industry. In this study, two oxidation systems are evaluated: the first one is based on the use of hydrogen peroxide at various levels of alkalinity; the second one investigates the use of sodium periodate followed by hydrogen peroxide to convert aldehydes into carboxyls and enhance their hemicelluloses removal. Our results have shown that when using only peroxide, the removal of hemicelluloses was not sufficient to improve the pulp’s dissolving ability. Conversely, the periodate–peroxide system proved to be more efficient. Results regarding the pulp purity, solubility, degradation (pulp viscosity and cellulose molecular mass distribution), brightness, and its potential applications were discussed.

The Impact of Hydrolysis Regime on the Physical and Mechanical Characteristics of Medium-Density Fiberboards Manufactured from Recycled Wood Fibers

Recycling medium-density fiberboards (MDF) presents notable technological challenges, primarily due to the deteriorated properties of the recycled wood fibers obtained from MDF waste. On the other hand, the enhanced valorization of recycled wood in the manufacturing of wood composites represents a viable approach for implementing the principles of a circular bio-economy in the wood-based panel industry and lowering its carbon footprint. This research aimed to investigate and evaluate the impact of the hydrothermal hydrolysis regime on the physical and mechanical properties of recycled MDF panels (rMDF). The hydrolysis temperature was varied from 121 °C (saturated steam pressure 0.2 MPa) to 134 °C (saturated steam pressure 0.3 MPa), and three hydrolysis durations, i.e., 30, 45, and 60 min, were applied. A control MDF panel, manufactured in laboratory conditions from industrial pulp, was used to perform the comparative analyses. It was observed that the degradation of the rMDF panels occurred when the hydrolysis temperature was increased from 121 °C to 134 °C. The research confirmed the deteriorated physical and mechanical properties of rMDF compared to the panels manufactured from natural wood fibers. Markedly, no significant differences were detected between the density profiles of the rMDF panels and the control boards fabricated from industrial pulp. As a result of the study, it was found that the hydrolysis temperature has a more significant effect than the processing time. It was also established that, in the preliminary preparation of the MDF panels into samples with dimensions similar to those of pulp chips, the optimal hydrolysis regime is at a temperature of 121° C (saturated steam pressure 0.2 MPa) and a time of 30 min.

Characterizing jamming of dilute and semi-dilute fiber suspensions in a sudden contraction and a T-junction

The clogging or jamming of particle suspensions is a ubiquitous problem, hindering the efficiency of particle–liquid and particle–particle separations. Motivated by pressure screening in the pulp and paper industry, we characterize jamming of dilute and semi-dilute mono-disperse rigid-rod suspensions passing through channels mimicking dead-end and cross-flow filtration membranes, experimentally, using particle-tracking velocimetry. We observe that jams nucleate by either bridging of isolated particles across the constriction, or by localized mechanical entanglement of the particles, i.e., flocculation. Uniquely, we observe floc-formation during acceleration into the aperture and report this as primary mechanism for jamming events. We characterized the accumulation-release cycles of the jamming event using an exponential probability distribution; this distribution is indicative of a Poisson process. For jams nucleated by single-particle bridging, the distribution is (primarily) related to the number of fibers passing through the aperture; this is similar to dry, granular materials. For floc-based nucleation events, the distribution is (primarily) related to the suspension concentration with the average time between jams decreasing inversely with the square-root of the initial suspension concentration. For the conditions tested, the distribution was insensitive to changes in constriction geometry.

SUSTAINABLE DEVELOPMENT IN UTTARAKHANDS PULP AND PAPER INDUSTRY: A COMPREHENSIVE RESEARCH ANALYSIS

This research paper delves into the Pulp and Paper Industry in Uttarakhand, exploring its historical development, technological advancements, environmental impact, regulatory landscape, and proposed strategies for sustainable development. Uttarakhands rich forest resources make it a significant contributor to the paper manufacturing sector, with a historical reliance on traditional manufacturing processes. However, the industry has undergone transformative changes to adopt sustainable practices, such as high dependence on biomass residues for energy. Technological advancements, including mechanical and chemical pulping innovations, recycled fiber processing, digital printing, nanotechnology applications, and energy-efficient processes, have played a pivotal role in improving environmental sustainability. The environmental impact, including deforestation, air and water pollution, and greenhouse gas emissions, is examined, emphasizing the need for sustainable forestry practices and clean energy sources. The paper also discusses relevant regulations and policies affecting the industry in Uttarakhand, along with existing challenges and opportunities. The research concludes with proposed solutions and strategies for achieving sustainable development in the regions Pulp and Paper Industry.

Chemical and rheological analysis of unaged and aged bio-extended binders containing lignin

The use of alternative renewable sources to totally or partially replace bitumen is one of the most current challenges in the road pavement sector. The growing energy cost and environmental concerns lead to the necessity to find alternative solutions, by supporting at the same time sustainability and circular economy principles. Within this framework, this paper presents the application of a powder lignin, a natural bio-polymer deriving from by-products of wood pulp and paper industry, to replace part of bitumen. The bituminous blend consisting in 70% of bitumen and 30% of powder lignin (by weight) was made in laboratory through the use of a high shear stirring mixer, and a reference plain bitumen characterized by a similar consistency (i.e., same penetration grade) was used as comparison. Then, an extensive investigation on chemical and rheological properties of the bio-binder is presented. Fourier transform infrared spectroscopy (FTIR), saturates, aromatics, resins and asphaltenes (SARA), bending beam rheometer (BBR), frequency sweep tests and multiple stress creep recovery tests (MSCR) with a dynamic shear rheometer (DSR) were performed. Moreover, unaged, short- and long-term aging conditions were considered. Results indicated that powder lignin dominates the rheological behavior of the bio-binder and, from chemical analysis, it seems that it partially acts as a filler and partially as a binder. This would result in improved performances at both low and high temperatures, leading to a wider temperature range of performance grade (PG). Moreover, despite a stiffening effect is recognized, lignin also offers an antioxidant potentiality, reducing the aging susceptibility of the investigated bio-binder.

Sustainable Utilization of Pulp and Paper Wastewater

The pulp and paper industry plays an important role in the global economy and is inextricably linked to human life. Due to its large scale, the production process generates a large amount of wastewater, which poses a major threat to the environment. The sustainable utilization and safe treatment of pulp and paper wastewater can effectively reduce environmental pollution, improve resource utilization efficiency, protect water resources, provide economic benefits for pulp and paper enterprises, and thus promote the green and sustainable development of the pulp and paper industry. Therefore, this study discusses the pollution components of pulp and paper wastewater and their impact on the environment and human health. In this review, we aim to explore the sustainable development of pulp and paper wastewater by summarizing the characteristics of current pulp and paper wastewater, the commonly used treatment methods for pulp and paper wastewater, the application of pulp and paper wastewater recycling, and the future development direction of pulp and paper wastewater.

THE IMPACT OF COVID-19 OUTBREAKS ON INDONESIA’S AUTOMOTIVE AND PAPER INDUSTRY STOCK RETURN

This study was carried out to identify the effect of COVID-19, Large-Scale Social Restriction policies, market capitalization, and stock trading volume on the company's stock returns from 2 March 2020 to 30 December 2020. The subjects in this study are companies in the automotive and component industries as well as the pulp and paper industry which are listed on the Indonesia Stock Exchange (IDX) during 2020. This study uses 3 theories, namely the Signaling Theory, Efficient Market Hypothesis Theory, and Black Swan Theory. Panel data regression analysis was used in the study, using EViews 9 program and Microsoft Excel to process all data. Results show that growth of COVID-19 positive cases and market capitalization have a significant negative effect on the company's stock return. The other results show that the increasing of LSSR (Large-Scale Social Restriction) policies and stock trading volumes have an impact on increasing company’s stock returns, while the growth of death cases of COVID-19 has no impact on increasing or decreasing company’s stock returns.

Instant Determination of Moisture and Bulk Density of Woodchips in Cellulose Industry

Purpose: This research aims to achieve the instantaneous determination of moisture content and bulk density of wood chips for energy generation and pulp production in the pulp and paper industry. Theoretical framework: The moisture content and bulk density of woodchips influence the quality of biomass for energy generation and cellulose production in various ways. These variables affect the calorific value, mass and volume of logistical transport, the quantity of reagents in the reactor for wood delignification, among other factors. For this reason, a quick and accurate evaluation of these factors in the field is of fundamental importance to improve industrial quality and productivity. Method: To achieve this goal, a pilot test was conducted using a capacitive sensor and a portable scale to determine the moisture and bulk density of wood chips. Calibration equations were developed in the laboratory for the sensor, correlating the readings with the actual moisture content of seven types of wood chips, including Eucalyptus spp. and Pinus spp. The results of field measurements using these equations were compared with the gravimetric method, as well as bulk density measurements. Results and conclusion: The moisture calibration equations showed a high correlation between the capacitive sensor and the gravimetric method. The field density results were similar to those obtained in the laboratory. It was concluded that the investigated methods show promise for use in the pulp and paper industry. Research implications: The validation and accuracy of portable instruments for the instantaneous determination of moisture content and bulk density of wood chips are of utmost importance for manufacturers of portable meters and for industries that use this raw material. Originality/value: The instantaneous determination of moisture content and bulk density can contribute to improving the energy and production efficiency of boilers that generate heat for pulp digesters. Moreover, it optimizes logistical transportation and quality control against the attack of xylophagous organisms, preventing waste of raw materials, which is essential for sustainable development.

Evaluation of kraft pulp, fibre and paper traits of interspecific hybrid Corymbia clones at four years

Two interspecific Corymbia hybrid clones, ITC 2081 & CH440 (Corymbia torelliana × C. citriodora subsp. variegata), were evaluated for growth, pulp, fibre and paper properties at four years in comparison to an E. camaldulensis (Ec) clone. Wood basic density and fibre traits were estimated from increment core samples and logs were chipped for evaluating pulp and paper traits. The Corymbia clones had comparable growth, but wood basic density was 12% higher than the Ec clone. The fibre traits were superior, with 24% larger fibre in the Corymbia hybrid clones, and 2% higher pulp yield (Kappa number 17) than the Ec clone. The Corymbia hybrid clones had comparable unbleached hand sheet brightness of the Ec clone but were superior in parameters like sheet stiffness, thickness, burst and tear factor. While Ec clones have attained the threshold of pulp wood traits improvement, the new Corymbia hybrids have demonstrated potential for improving the profitability of pulp industries in India.

Ether Bond Formation in Waste Biomass–Derived, Value-Added Technical Hardwood Kraft Lignin Using Glycolic Acid

Ether bond formation in technical hardwood kraft lignin (THKL) by crosslinking using glycolic acid was investigated for bio-adhesive applications. Industrial hardwood kraft black liquor was used to extract the THKL utilized by acidification. Chemical and thermal properties of the THKL with and without crosslinking were analyzed by Fourier transform infrared (FTIR) spectroscopy, solid-state 13C cross-polarization/magic angle spinning nuclear magnetic resonance (13C CP/MAS NMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). FTIR results revealed a new peak corresponding to the ether bond and hemiacetal formation due to crosslinking at 1075 cm-1 and 1324 cm-1. 13C CP/MAS NMR spectra revealed the presence of a higher number of ether bonds due to the reduced aromatic and aliphatic hydroxyl groups in THKL and new bonds formed at 62-64 ppm and 168-191 ppm due to crosslinking. XPS results revealed that new bonds were formed between glycolic acid and THKL, leading to increased atomic oxygen percentage and carbon–oxygen bonds in crosslinked THKL detected by peak intensity changes at 287.7 and 288.8 related to O–C–O and O–C=O. Also, the oxygen content increased from 14.88% to 31.76% due to bond formation. GPC confirmed a higher molecular weight and broader molecular-weight distribution of THKL. DSC and TGA curves of crosslinked THKL revealed exothermic behavior, high thermal stability, and low thermal degradation rate. Owing to a significant amount of kraft black liquor being generated by wood pulp industries and attractive chemical properties of THKL, THKL demonstrates promise as a raw material to produce green, sustainable bio-adhesives via the crosslinking of its different hydroxyl groups using glycolic acid.

Screening of Eucalyptus camaldulensis clones for enhancing productivity and sustainability in problematic soils of Southern India

Among the various challenges faced by eucalyptus plantations in the Indian pulp industry, one of them is the development of resilient clones adaptable to saline soils. Large genetic diversity exists in E. camaldulensis because of high out-crossing rates and is expected to pass traits into the new developed clones. We used a salt injury score, survival percentage and proline content as a screening criterion to select new clones tolerant to high salt levels in soils. Proline has been identified as a beneficial solute in plants under stress caused by high salinity. Three months old clones of eleven new eucalyptus genotypes were transplanted in pots with free-draining coarse river sand. Four treatments comprising control, high Salt, High Salt + High pH and High pH were arranged in a randomised block design. Common salt (NaCl) was used for regulating salt concentrations while sodium bicarbonate (NaHCO3) was used for regulating the pH of the solutions. NaCl concentrations were increased every third day until the final concentration of 150 mM was reached. Similarly, pH of the solutions was also gradually increased till final pH of 10 was attained. Each treatment solution was delivered through automated drip delivery. Salt injury scores based on symptoms were positively correlated (0.812) with survival percentage and proline content. Eucalyptus genotypes were classified into five salt tolerant groups: tolerant (T), moderately tolerant (MT), moderately sensitive (MS), sensitive (S), and highly sensitive (HS). The mean values of proline content in leaves were different among the five groups, indicating that the proline content is a reliable marker for identifying salt tolerance. Proline contents in stressed seedlings were significantly different between the tolerant and highly sensitive groups, but the difference among the intermediate groups (MT, MS and S) was not significant. As the stress levels of salt and pH were increased, the sensitive hybrid clone tested showed very poor growth, which was also negatively correlated with the proline content in its leaves. Combination of high salt and high pH was also found to be correlated with reduced proline content, poor growth and survival among sensitive genotypes. In addition to the commonly used sodium and pH induced symptoms, proline content is suggested to be another useful criterion to differentiate salt-tolerant from salt-sensitive genotypes. This study helped in classification of genotypes with different levels of salt and pH tolerance, which may be used for deployment of genotypes according to changing edaphic conditions for sustainability of eucalyptus plantations.

Effect of different cytokinin sources on in vitro/ex vitro multiplication and rooting rate in Eucalyptus spp.

Eucalyptus globulus Labill. is of great interest to the pulp industry. However, the species is highly susceptible to leaf spot caused by Teratosphaeria nubilosa and has a low rooting capacity. In order to overcome these limitations, INIA has been implementing a genetic improvement program for this species and the generation of interspecific hybrids. The strategy is based on the selection of E. globulus clones with high precocity or foliage turnover, since the adult foliage is more tolerant to T. nubilosa. In addition, controlled crosses of E. globulus and E. maidenii with E. grandis are carried out to incorporate disease resistance and ease of rooting. The multiplication of the selected materials is carried out by micropropagation, but the low rooting capacity is a trait that needs improvement. The cytokines necessary for in vitro proliferation can have a negative effect on the rooting process. Benzyladenine is the most commonly used cytokine because of its low cost and easy availability, with some negative effects on rooting, while meta-topolin is a cytokine of lesser impact. The objective of this study was to evaluate the effect of benzyladenine and meta-topolin on the multiplication rate, rooting percentage and plantlets survival of E. globulus, E. grandis × E. globulus, and E. grandis × E. maidenii. In multiplication media, benzyladenine was supplied at 0.4 µM, while two concentrations of meta-topolin (0.4 and 2 µM) were used. Preliminary results indicated a higher multiplication rate with the inclusion of meta-topolin in both concentrations. The in vitro rooting percentage of explants treated with meta-topolin was 51% and 44%, at 0.4 and 2 µM, respectively, while with benzyladenine was lesser (37%). After 28 days post-transplanting, survival was higher in meta-topolin-derived plants. Meta-topolin improved multiplication, in vitro rooting and acclimation of plants. The use of this hormone could improve micropropagation protocols, facilitating rooting and multiplication of valuable genotypes.

Classifying health issues in Eucalyptus miniclonal gardens in Uruguay

Clonal propagation is extensively used in the Eucalyptus pulp industry in Uruguay. Mother plants are maintained in clonal minigardens and they constitute the source of cuttings that are harvested continuously and sent to shaded greenhouses for rooting. Environmental conditions within the minigarden are optimized for plant growth, but such conditions can also promote the emergence of pests and diseases which can affect the mother plants and impair cutting production. However, comprehensive studies on health status within minigardens are scarce in the country. We carried out a seasonal survey on three clonal minigardens along the country to check for epidemiological patterns connected to the time of the year, the conditions within the clonal garden and the genetic material in propagation. We visited each minigarden at least once per season during 2019 and the beginning of 2020. During each visit, we inspected all the mother plants along three transects (two on the edges and one in the centre of the minigarden). We counted the number of plants with symptoms of disease and of insect attacks, and collected samples of affected plants for further identification in the laboratory, if necessary. We looked for a way to classify nurseries and species all together, according to the incidence of the different health issues surveyed. Thus, the dataset obtained from the surveys was assessed under different classification algorithms based on machine learning: neural networks, discriminant analysis models, classification regression tree, support vector machine, and random forest. We observed attack by arthropods such as mites, whiteflies, scales and aphids and caterpillars. We also recorded powdery mildew and disease symptoms such as dead plants and dry shoots. The different materials assessed during the survey belonged to E. grandis, E. dunnii, and E. grandis × E. globulus hybrids. The most common symptoms observed in all the minigardens and throughout the entire survey period were powdery mildew and damage from mites. The support vector machine model performed best, being able to classify the dataset with an accuracy of 76%. We discuss the relevance of these findings within the context of miniclonal garden health management.

ELECTROCHEMICALLY TREATED LIGNIN IN PHENOLIC RESINS FOR PLYWOOD PANELS

In achieving the European Union's goal of making Europe the first climate-neutral continent by 2050, the scientific community is striving to develop processes and products that are technologically and economically sustainable to replace/substitute fossil-based feedstocks. In this effort, the European project LIBERATE has demonstrated the commercial opportunities of converting low-cost lignin feedstocks into high-value bio sustainable chemicals such as vanillin and mixed phenolic derivatives.Lignin is the largest regenerative source of aromatic organics. In current wood pulping industries, lignin is underutilized and widely considered a side stream primarily exploited for its energy content. A promising approach for the synthesis of biobased fine chemicals is a depolymerisation process for lignin using sodium peroxodicarbonate (PODIC®), an electrochemically produced oxidiser. Within the LIBERATE project, SINTEF has built a pilot scale plant for the electrochemical lignin depolymerisation. The plant provided CHIMAR with the phenol-rich reactor product solution from both kraft and organosolv lignin, which was used as phenol substitutes with up to 50wt% in the formulation of phenol-formaldehyde (PF) resins. These resins have been able to produce successful plywood panels on a laboratory scale. Although their quality is somewhat lower than that of the reference material with traditional PF resin, this work showed that the use of lignin fractions obtained by electrochemical treatment in such an application is possible and promising.

Carbon emissions analysis of the pulp molding industry: a comparison of dry-press and wet-press production processes

Abstract An initial carbon emission calculation formula for the pulp molding industry was first proposed in accordance with the calculation guidelines provided by the Intergovernmental Panel on Climate Change (IPCC). The formula was primarily developed by utilizing the greenhouse gas accounting methods used in the pulp and paper industry and the life cycle assessment (LCA) theory. Carbon dioxide emissions coming into being during the production processes of dry-press and wet-press pulp molding were calculated individually, alongside the carbon emission factors throughout the lifecycle of the products. This study also delivers a comparative analysis of pulp molding products and similar cushion packaging materials. Moreover, the findings reveal that during the production phase, particularly in the formative stages of pulp molding, substantial carbon dioxide emissions would be produced, with dry-press pulp molding products exhibiting markedly higher carbon emission factors than their wet-press counterparts. The primary objective of achieving low-carbon transformation for the pulp molding industry was to reduce the carbon emissions caused by the forming process, primarily by improving the forming process and enhancing energy efficiency or utilizing clean energy.

Integration of carbon capture in a pulp mill—effect of strategic development towards better biomass resource utilization

The pulp and paper industry has an important role in the industrial transition towards net zero or negative emissions, given its renewable biomass-based feedstock and energy supply. In particular, pulp and paper mills have large existing sources of biogenic CO2, with a high potential to contribute to carbon dioxide removal through carbon capture and storage (CCS). To effectively navigate anticipated changes in feedstock and energy markets, there is a need for a better understanding of how different technology pathways for the pulp and paper industry interact with one another, for instance, how enhanced valorization of biomass side streams may affect the potential for carbon capture. This paper aims to investigate the effect of combining carbon capture with lignin extraction in a chemical pulp mill. Pinch analysis is used to study how the targets for heat recovery, fuel usage and electricity generation, are affected by different mill and capture configurations. Based on these results, the effect on carbon flows is evaluated. The results show that when carbon capture technology is implemented and fuel use is minimized at the case-study mill, there is still enough heat available from the recovery boilers to supply the process needs without requiring usage of a utility boiler. However, when carbon capture is combined with lignin extraction, the heat production of the recovery boilers is no longer sufficient to cover the process demands, and additional heat from a utility boiler is required. However, this case implies that some of the carbon leaves the mill embedded in the extracted lignin product, which can be expected to have a higher value than captured carbon dioxide. When back-pressure electricity production was maximized for the different mill configurations, a very high fuel-to-electricity efficiency could be achieved, but since the CO2 emissions from the utility boiler were not assumed to be captured, this would lead to more carbon being emitted compared to the capture scenarios with minimized fuel use.

Pulp and paper mills: The original biorefineries — past performance and limitations to future opportunities

Pulp mills have been biorefineries since the invention of the Tomlinson recovery boiler. Unfortunately, the paper industry has done a poor job explaining that concept to the general public. A number of bioproducts in everyday use have been produced by pulp mills for several decades, and new products are routinely being developed. Modern research efforts over the last couple of decades have focused on producing even more products from pulp and paper mills through capacity enhancement and the development of value-added products and liquid transportation fuels to enhance paper mill profitability. Some of these efforts, often referred to as modern biorefineries, have focused so heavily on product development that they have ignored operating and process realities that limit the transformation of pulp and paper mills from the current limited number of bioproducts produced today to economic scale production of these value-added products. In this paper, several of these limitations are addressed. In addition, there are several supply chain, marketing, product quality, and economic realities limiting the value potential for these wholesale conversions of pulp mills into multiproduct modern biorefineries. Finally, the conservative nature and capital intensity of the pulp and paper industries provide a difficult hurdle for conversion to the modern biorefinery concept. These issues are also reviewed.

EFFECT OF PULP SLUDGE COMPOST VS. MANURE FERTILIZER APPLICATION TO THE GROWTH OF GERONGGANG (Cratoxylum arborescens) SEEDLINGS IN PEAT SOIL

The pulp industry is crucial for Indonesia, but the waste produced should be managed. Pulp sludge contains organic matter suitable for compost material. This study examines the response of geronggang (Cratoxylum arborescens) seedlings' growth to the application of pulp sludge compost compared to commercial manure fertilizer and non-fertilized soil for six months. A fifteen kg of pulp sludge (water content of 60-70%) mixed with decomposers (Penicillium citrinum and Penicillium oxalicum (107 spores/mL)) was incubated for a month. The compost or fertilizer at a dosage of 0, 2, 4, 6, 8, 10, 12, 14, and 16 (tons/ha) was added to peat soil for the seedlings' growing media. The manure fertilizer contained higher macronutrients than the sludge compost, while the peat was considered poor soil. Seedlings with sludge compost or manure fertilizer addition at a dosage equal to 2 (tons/ha) showed the highest survival rate after six months. The sludge compost addition raised the seedling's height, diameter, and dry weight more than another treatment. The sludge compost at a dosage equal to 16 and 12 (tons/ha) significantly increased the height and diameter of the seedlings, respectively. The sludge compost has shrink-swell characteristics that are potent water retention in dry soil.

Performance evaluation and microbial profiling of integrated vertical flow constructed wetland (IVFCW) for simultaneous treatment of domestic and pulp and paper industry waste water

The present study demonstrates the potential of an integrated vertical flow-constructed wetland (IVFCW) for simultaneously treating black liquor and domestic wastewater. IVFCW was operated and monitored for 12 samples with the frequency of one sample per week with the following specifications viz,4 L of wastewater, a blend of 1:1 of pulp and paper industry effluent (black liquor BL), and domestic wastewater, was fed daily in a continuous mode with organic loading rate (OLR) of 1230 mg COD/L-Day, at a temperature range of 40-45℃ (natural temperature of the workstation). Valves controlled each chamber's hydraulic retention time (HRT) of 3 days and flow rate of 10 mL/minute. The IVFCW showed remarkable efficiency in removing various pollutants, including total suspended solids (TSS) and total dissolved solids (TDS), by 100 % and 83 %, respectively, and organic contaminants such as chemical oxygen demand (COD) and biological oxygen demand (BOD) by 80 % and 81 %, respectively. Moreover, the IVFCW efficiently reduced nutrients such as sulfates (SO₄-2), phosphates (PO₄-3), and total nitrogen by about 81 %, 63 %, and 61 %, respectively. The treatment also led to the reduction of lignin content by 83 %. Microbiological analysis revealed a significant reduction in fecal coliforms, and microbial profiling of Typha latifolia roots confirmed the presence of bacteria involved in lignin degradation. Seed germination and seedling survival were found to be negativelyaffected by untreated wastewater in a phytotoxicity study, suggesting that the wastewater's toxic chemicals could be harmful to plant life.This study highlights the effectiveness of IVFCW as a sustainable, economically viable, and resilient wastewater treatment system for mitigating environmental concerns related to the release of untreated wastewater.

Enzymatic Hydrolysis of Kraft and Sulfite Pulps: What Is the Best Cellulosic Substrate for Industrial Saccharification?

Sulfite and kraft pulping are two principal methods of industrial delignification of wood. In recent decades, those have been considered as possibilities to pretreat recalcitrant wood lignocellulosics for the enzymatic hydrolysis of polysaccharides and the subsequent fermentation of obtained sugars to valuable bioproducts. Current work compares chemistry and technological features of two different cooking processes in the preparation of polysaccharide substrates for deep saccharification with P. verruculosum glycosyl hydrolases. Bleached kraft and sulfite pulps were subjected to hydrolysis with enzyme mixture of high xylanase, cellobiohydrolase, and β-glucosidase activities at a dosage of 10 FPU/g of dry pulp and fiber concentration of 2.5, 5, and 10%. HPLC was used to analyze soluble sugars after hydrolysis and additional acid inversion of oligomers to monosaccharides. Kraft pulp demonstrated higher pulp conversion after 48 h (74–99%), which mostly resulted from deep xylan hydrolysis. Sulfite-pulp hydrolysates, obtained in similar conditions due to higher hexose concentration (more than 50 g/L), had higher fermentability for industrial strains producing alcohols, microbial protein, or organic acids. Along with saccharification, enzymatic modification of non-hydrolyzed residues occurred, which led to decreased degree of polymerization and composition changes in two industrial pulps. As a result, crystallinity of kraft pulp increased by 1.3%, which opens possibilities for obtaining new types of cellulosic products in the pulp and paper industry. The high adaptability and controllability of enzymatic and fermentation processes creates prospects for the modernization of existing factories.