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The urgent need for sustainable waste management strategies has led to the exploration of innovative approaches for the valorization of waste. In this study, a method is proposed for carbonizing waste biomass materials, particularly paper mill waste sludges (primary and biological) and knots, to produce porous carbonaceous supports. Through an initial hydrothermal carbonization followed by carbonization with nitrogen flow, porous carbon materials are successfully generated. The findings of this investigation validate the successful generation of effective carbonaceous supports utilizing waste biomass materials. These materials are then evaluated for their effectiveness as porous supports in the ionic liquid‐catalyzed cycloaddition reaction of CO2 to styrene oxide, achieving a remarkable conversion rate of up to 98% and an impressive selectivity exceeding 99%. Additionally, the results underscore the significant impact of the selected IL on the overall conversion process. Overall, this study presents a promising pathway for the valorization of paper mill waste sludge through the production of porous carbon materials with potential applications in catalysis and beyond. [ABSTRACT FROM AUTHOR]

This study investigated converting abundant paper mill waste, de‐inked paper sludge (DPS), into value‐added medium‐density fiberboard (MDF) panels. The objective was to repurpose this solid waste into a valuable material that aligns with the principles of a circular economy. Previous research has examined the addition of paper sludge to wood composites, but there is limited information on the specific incorporation of DPS into MDF production. This investigation offers new insights into this application. MDF panels were manufactured using hardwood fibers, with varying levels of urea‐formaldehyde resin (10% and 12% by weight) and different loadings of DPS (ranging from 0% to 50% by weight). X‐ray diffraction analysis revealed the presence of defective DPS fiber crystals. Contact angle measurements confirmed that DPS had poor wettability, corresponding to increased water absorption. As more DPS was incorporated, the mechanical properties of the panels progressively weakened due to defective fibers and poor adhesion between the fibers and the matrix. This was evident in scanning electron microscopy micrographs, which showed an escalation in interfacial flaws. Increasing the resin dosage noticeably improved the internal bond strength and reduced moisture uptake across all levels of DPS. However, at a DPS loading of 50%, the properties of the panels deteriorated by 36%–57% compared to the control MDF. Additionally, thickness swelling and water absorption increased significantly with higher DPS content, primarily due to the hydrophilic nature of the fibers. Based on optimization, it was determined that a DPS loading of 20% with a resin content of 12% provided the best balance between performance, waste utilization, cost, and moisture resistance. The reuse of abundant paper sludge supports the goals of a circular economy. However, strategies are required to tailor the processing methods and enable higher levels of recycled material without excessively compromising the key attributes of the product. Further research should focus on enhancing the quality of DPS and its compatibility with wood fibers and resin to enhance the performance of the composite material. Highlights: DPS from recycled paper mill assessed for MDF production with wood fibers and resinIncreasing DPS loading caused reductions in strength and adhesion of panelsWater absorption and thickness swelling markedly rose with more DPS additionIt was attributed to hydrophilic fibers and disrupted fiber‐matrix bondingOptimal formulation was 20% DPS loading and 12% resin content, balancing performance, waste utilization, and cost. [ABSTRACT FROM AUTHOR]

The acidic soils of western Newfoundland require liming for successful production of most crops. Locally sourced paper mill waste wood ash (WA) and paper sludge (SL) have potential as cheaper alternatives to limestone (LIME). Two greenhouse experiments evaluated WA and SL as liming and soil conditioning amendments for annual ryegrass (Lolium multiflorum) production. At 55 days after seeding, soil pH in WA (6.2 and 6.3) and wood ash and paper sludge (WASL) (6.0 and 6.3) were not different from that in LIME (6.0 and 6.5) for Experiments 1 and 2, respectively. However, pH in SL was 0.4 and 0.3 points lower than in LIME. Compared to LIME, WA, SL, and WASL produced 31%–52% and 57%–74% greater biomass yield in Experiments 1 and 2, respectively. N uptake was greater in WA (60 and 129 kg N ha−1) and WASL (51 and 97 kg N ha−1) compared to LIME (40 and 85 kg N ha−1), in Experiments 1 and 2, respectively. SL did not differ from LIME in Experiment 1, but reduced N uptake by 57% in Experiment 2. The results show significant potential of WA as an alternative amendment for liming and yield improvement of annual ryegrass grown in NL podzolic soils. However, SL has limited potential due to the risk of increasing N immobilization and residual soil mineral N when growing conditions are limiting. Combining SL with WA or biochar seemed to alleviate these risks. Overall, the adoption of these amendments for field production systems warrants serious consideration, following supplemental field studies to determine optimal application rates and timing. Core Ideas: The podzolic soils of Newfoundland have low pH and fertility, hence require liming.Locally sourced wastes, such as paper mill wood ash (WA) and sludge (SL), could be used as liming and nutrient sources.WA was equivalent to limestone (LIME) in improving and sustaining optimal soil pH.WA produced 52% and 74% greater annual ryegrass yield than conventional LIME application in podzolic soils. [ABSTRACT FROM AUTHOR]

The incineration of high‐moisture solid residues generated at the recycling paper mills represents an energetically unfavourable method of resource utilization. Alternatively, hydrothermal pre‐treatment is considered. In this study, low‐value paper sludges from three different recycling streams were hydrothermally carbonized at 205, 225, and 245°C for 3 h. The raw feedstocks and derived hydrochars were analyzed for energy properties, chemical characteristics, surface morphology, functional groups, and combustion performance employing energy densification and mass yield quantification, scanning electron microscopy, elemental analyzer, Fourier‐transform infrared spectroscopy, and thermogravimetry. The increase in reaction temperature was reported to cause a decrease in mass yield and an increase in energy densification and calorific values corresponding to 5.98%–49.35% and 10.10%–58.51% for raw fibre rejects and final sludge‐derived hydrochar, respectively. Hydrothermal carbonization (HTC) had a non‐significant influence on the energy densification of primary clarifier sludge‐derived hydrochar. Higher reaction temperatures favoured the rate of dehydration and decarboxylation, leading to hydrochars with lower H/C and O/C ratios, thereby enhancing the overall fuel properties. The low‐nitrogen and low‐sulphur fuels obtained validated the effectiveness of HTC treatment to produce high‐quality cleaner solid fuel. The burnout temperature was mostly reduced with an increase in HTC temperature. At HTC‐205 and 225°C, the ignition temperature and the combustion performance increased as a result of the HTC reaction mechanisms. HTC effectively recovered hydrochar with increased carbon content, improved energy densification, and good combustion adequacy. Hydrochar derived from recycling mills may play a role in the energy sector as a substitute for coal or in co‐combustion at coal‐fired power plants. [ABSTRACT FROM AUTHOR]

Photosynthetic cyanobacteria have attracted interest as production organisms for third‐generation biofuels, where sunlight and CO2 are used by microbes directly to synthesize fuel molecules. A particularly suitable biofuel is n‐butanol, and there have been several laboratory reports of genetically engineered photosynthetic cyanobacteria capable of synthesizing and secreting n‐butanol. This work evaluates the environmental impacts and cumulative energy demand (CED) of cyanobacteria‐produced n‐butanol through a cradle‐to‐grave consequential life cycle assessment (LCA). A hypothetical production plant in northern Sweden (area 1 ha, producing 5–85 m3n‐butanol per year) was considered, and a range of cultivation formats and cellular productivity scenarios assessed. Depending on the scenario, greenhouse gas emissions (GHGe) ranged from 16.9 to 58.6 gCO2eq/MJBuOH and the CED from 3.8 to 13 MJ/MJBuOH. Only with the assumption of a nearby paper mill to supply waste sources for heat and CO2 was the sustainability requirement of at least 60% GHGe savings compared to fossil fuels reached, though placement in northern Sweden reduced energy needed for reactor cooling. A high CED in all scenarios shows that significant metabolic engineering is necessary, such as a carbon partitioning of >90% to n‐butanol, as well as improved light utilization, to begin to displace fossil fuels or even first‐ and second‐generation bioethanol. [ABSTRACT FROM AUTHOR]

This is a review of literature published in 2017 related to the prevention of water pollution by or recovery of beneficial materials from wastewater produced in the pulp and paper industry. This review includes the following main sections: cleaner production, biological treatment, and physico-chemical treatment. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial strain Rhizobium sp. was isolated from littoral soil of meteoric alkaline Lonar Lake and used to treat paper mill waste water. The bacterium was found to fix 125.7 nmol of C2H4 formed ml−1 culture media in 72 hr by ARA (acetylene reduction assay). The optimum pH for its growth was 12, whereas the optimum temperature was 40°C. The bacterium could tolerate salt concentrations up to 4%. The collected paper mill effluent used two dyes in combination, namely Acid Orange 7 (AO) and Acid Yellow 17 (AY) to produce brown paper, eventually producing coloured effluent containing unbound AO and AY. Rhizobium sp. was found to be efficient for decolorization of both AO and AY individually, as well as in a mixture of AO and AY, suggesting the ability of this strain for treating paper mill effluent. The strain was found to be efficient in reducing up to 85% of the colour from undiluted paper mill effluent within 18 hr. In addition, biotreatment also was effective in reducing COD, metals and toxicity from the waste water. Induction in the enzymes azo reductase and DCIP reductase indicated their possible involvement in biotreatment of paper mill effluent. The effluent toxicity before and after treatment was studied using Allium cepa root cells, evaluating various biochemical parameters to assess the toxicity, including lipid peroxidation, protein oxidation, antioxidant enzyme status (catalase, superoxide dismutase) and genotoxicity assays using single cell gel electrophoresis (SCGE). [ABSTRACT FROM AUTHOR]

To relief the water shortage crisis in China, the Chinese government has initiated a series of clean production (CP) measures to reduce the freshwater consumption and wastewater discharge from paper industry. In this study, a new CP technology was introduced in the paper industry to reuse tissue paper mill effluent water as intake water of corrugated paper mill. The feasibility and impact of the new CP technology was investigated in three different scales, laboratory experiments, pilot‐scale testing, and long‐term implementation. Results show that the water quality of treated tissue paper mill effluent water is competitive with that of freshwater and some water quality indexes are even better, indicating that treated tissue paper mill effluent water is a suitable alternative to replace the freshwater as intake water for the corrugated paper mill. By reusing tissue paper mill effluent water as intake water of corrugated paper mill, most physical properties of different corrugated paper layers are improved or similar as those by using freshwater as intake water in all different scale experiments. Moreover, the new CP technology significantly reduced the freshwater consumption for the corrugated paper mill, eliminated the wastewater discharged from the tissue paper mill, and at the same time, lowered the operation cost for both paper mills in terms of freshwater consumption and wastewater treatment cost. Total 216,000 RMB will be saved every year with an assumption that tissue paper mill provides annual daily average 2000 cubic meter of effluent water to corrugated paper mill every day. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 934–941, 2018 [ABSTRACT FROM AUTHOR]

This is a review of literature published in 2016 related to the prevention of water pollution by or recovery of beneficial materials from wastewater produced in the pulp and paper industry. This review includes the following sections: pulp and paper wastewater management, pollution avoidance, process modelling, physical and chemical treatment, biological treatment, phytoremediation and value added materials. [ABSTRACT FROM AUTHOR]

This work presents an effective way to remove ammonium from compost using corn wastes. The study examined the role of experimental factors on the removal of ammonium using a full factor experimental design. The experimental factors and their related levels selected were as follows: Material type (corn cob and corn husk), ratio (10 and 25%), moisture (50 and 70%), and finally duration (30 and 60 days). The results were evaluated with an ANOVA test. A regression model that took into account the significant main and interaction effects was suggested. According to the optimization algorithm, the optimum levels were corn cob, 25% ratio, 50% moisture, and 60-day duration, with a removal efficiency of 91.84%. The proposed procedure is simple to implement and cost-effective. [ABSTRACT FROM AUTHOR]

Stabilization of organic matter ( OM) is an important topic in soil science, but it is not yet completely understood. Recent interest in the recovery of poor or damaged soil with the addition of OM from waste such as paper mill sludge has led to further research on this topic. Research on the association of OM with soil minerals is difficult; therefore, most of the experimental studies published have been carried out on natural (not treated) or artificial soil. In this paper, we describe the use of both 1H nuclear magnetic resonance relaxometry in the time domain ( TD-MRR) and N2 adsorption-desorption techniques to characterize samples of soil taken from a hillside treated with paper mill sludge. We have shown that although both techniques are sensitive to different, but to some extent complementary, scales of pore sizes, they can highlight the clogging effect of OM on soil pores (in a range of pores sizes from a few nm to several µm). The relations with total organic carbon were similar for the bound water porosity evaluated by TD-MRR and the specific surface area determined by N2 adsorption-desorption. This new approach that uses both TD-MRR and N2 adsorption-desorption also suggests that OM is well protected in small pores (≤ 2 µm), especially when there is preferential association with minerals, for example with kaolin clay and carbonates. Highlights Characterization of the porosity of soil sampled from a hillside treated with organic waste., The combined use of 1H nuclear magnetic resonance relaxometry and N2 adsorption-desorption techniques., There is a clogging effect of organic matter on soil pores from a few nm to several µm., Both techniques can be used to add information on potential TOC stabilization. [ABSTRACT FROM AUTHOR]

Stabilization of organic matter ( OM) is an important topic in soil science, but it is not yet completely understood. Recent interest in the recovery of poor or damaged soil with the addition of OM from waste such as paper mill sludge has led to further research on this topic. Research on the association of OM with soil minerals is difficult; therefore, most of the experimental studies published have been carried out on natural (not treated) or artificial soil. In this paper, we describe the use of both 1H nuclear magnetic resonance relaxometry in the time domain ( TD-MRR) and N2 adsorption-desorption techniques to characterize samples of soil taken from a hillside treated with paper mill sludge. We have shown that although both techniques are sensitive to different, but to some extent complementary, scales of pore sizes, they can highlight the clogging effect of OM on soil pores (in a range of pores sizes from a few nm to several µm). The relations with total organic carbon were similar for the bound water porosity evaluated by TD-MRR and the specific surface area determined by N2 adsorption-desorption. This new approach that uses both TD-MRR and N2 adsorption-desorption also suggests that OM is well protected in small pores (≤ 2 µm), especially when there is preferential association with minerals, for example with kaolin clay and carbonates. Highlights Characterization of the porosity of soil sampled from a hillside treated with organic waste., The combined use of 1H nuclear magnetic resonance relaxometry and N2 adsorption-desorption techniques., There is a clogging effect of organic matter on soil pores from a few nm to several µm., Both techniques can be used to add information on potential TOC stabilization. [ABSTRACT FROM AUTHOR]

ABSTRACT The disposal of paper mill sludge (PMS) is a difficult environmental problem. Thus, PMS has been used as a substitute for wood fiber (WF) to reinforce high-density polyethylene (HDPE). In this study, we compared PMS-WF-HDPE composites with composites without PMS after water immersion and thermal treatment. Water immersion and thermal treatment were conducted at 25 and 70°C, respectively. The results show that the composites with PMS absorbed less water but lost more of their original flexural properties after immersion; thereby, their strength was compromised. These reduced mechanical properties could be partially restored after redrying. After the thermotreatment, the composites with added PMS lost their weight and flexural properties, whereas the composites without PMS gained flexural strength. The results show that the thermotreatment improved the impact strength of the composites when no more than one-third of WF was replaced with PMS. Fourier transform infrared spectroscopy and energy-dispersive X-ray energy-dispersive spectroscopy showed that the wood index of the PMS composite decreased more than the index of the non-PMS composite, whereas the carbonyl index increased more. However, the PMS composite showed a lower increase in the total oxygen/carbon weight ratio. This study suggested that limited amounts of WF could be substituted with PMS to reinforce HDPE. However, WF-PMS-HDPE composites should not be used in hot, humid environments for long periods. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41655. [ABSTRACT FROM AUTHOR]

A review of the literature published in 2011 on topics relating to water pollution control and wastewater treatment issues in the pulp and paper industries is presented. This review is divided into the following sections: physico - chemical treatment processes, biological treatment (aerobic/anaerobic), use of magnetic field and iron-based complexes, use of mimic enzymes prepared from iron-based biomimetic compounds, advanced treatment methods, and constructed wetland. [ABSTRACT FROM AUTHOR]

Over the years, paper production and development processes have continuously changed to meet the demands of our society. Direct consequences are rapid transformation of production processes and use of new chemicals. Indirectly, changes have occurred to wastewater compositions and their impacts on the receiving environment. Mitigation of the negative impact of effluents depends on the development of advanced effluent management technologies that are both environmentally conscious and cost-effective. In 2009, a large number of publications targeted these issues. A set of manuscripts that best represent the 2009 literature on pulp and paper industry effluent management are reviewed herein. Publications have been grouped into the following areas of knowledge: Toxicology and Monitoring, Sustainability Practices, Biological Treatment, Physicochemical Treatment, and Biochemical Treatment. [ABSTRACT FROM AUTHOR]

The article offers information on the efforts of governments, consumers and industry to curb the plastics waste. It mentions that generation of post-consumer plastics waste according to European Plastic Recyclers, which represents plastic mechanical recycling companies. It discusses that European Plastic Recyclers separates recycling into three broad types including mechanical, chemical and energy recovery.

Paper production is among the industrial branches generating significant amounts of waste. Organic waste from paper manufacturing is mostly used in gardening and agriculture or converted for energy purposes, while inorganic waste, including green liquor dregs (GLD), is usually deposited on landfills. GLD has a highly alkaline reaction, suggestive of its possible utilization for land reclamation or for improvement of soil's physico‐chemical properties. The research results originate from a pot experiment with maize as the test plant. GLD was added to soil in doses 10–40 t ha−1. The trials consisted of two series: with and without tree bark (TB). GLD contributed to neutralization of the soil's acidic pH, enrichment of the sorption complex with alkaline cations, and to greater salinity of the soil. In the series with TB, it is demonstrated that GLD led to a decrease in the soil content of total organic carbon; while the content of total nitrogen increased, the C:N ratio is considerably narrowed. In response to GLD, the greenness of leaves significantly improves, but this does not translate into an increase in the yield of plants. Regarding the chemical composition of plants grown in soil treated with elevated GLD doses, the content of N and Na is demonstrably higher, although no such effect is discernible in the case of P and K. For the environment, safe doses of the applied waste, not causing significant deterioration of soil properties or depressing crop yields, are 10 and 20 t GLD ha−1. [ABSTRACT FROM AUTHOR]

The article looks at the development of a polymer compound made from wood, saying it could be a biodegradable replacement for polystyrene in consumer products. It notes the polymer is synthesized from waste from paper mills containing lignin. Topics include the compound's tolerance for high temperatures and research on alternatives for polyethylene.