Waste Paper Research Articles

Evaluating the properties of deinking paper sludge from the Mediterranean area for recycling in local areas as a soil amendment and to enhance growth substrates

AbstractRecycling of paper generates large quantities of paper sludge that is rich in organic matter and can be exploited to counteract organic matter loss in agricultural soils, especially in some geographical areas, such as the Mediterranean. In order for deinking paper sludge (DPS) to be recycled, chemical and physical characterizations are required along with an analysis of possible contaminants. DPS from Italy and Tunisia, resulting from various deinking processes, were analyzed and compared in terms of their chemical properties (pH, OM, total N, C/N ratio, mineral nutrients, and trace metals), surface chemistry [diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and Fourier-transform infrared (FTIR) spectroscopy], and thermal stability [thermogravimetric analysis (TGA)]. The aim was to improve their use as amendments in soils or growth substrates. Elemental analysis revealed higher carbon concentrations in the Tunisian DPS and similar nitrogen contents, high mineral nutrient levels, and potentially toxic trace element levels below the limits allowed for soil amendment. No evidence was found for the presence of organic pollutants, pathogens, or toxic heavy metals. Surface chemical analysis revealed comparable materials rich in aromatic, phenolic, aliphatic, and polysaccharide structures along with clay minerals and carbonates. The thermal analysis revealed similar decomposition temperatures for the organic matter. Practical implications of the results are discussed, highlighting the similar properties of sludge following ink removal by different processes and the need to integrate the N content in order to be able to employ sludge as an amendment in soil and growing media. Given the similarity of the compositions of the materials, appropriate DPS management is key to improving soil fertility, reducing paper waste disposal, and implementing a circular economy in the Mediterranean, where climate change is having a significant impact.

Evaluating the effect of paper waste lignin in hot mix asphalt

Asphalt is a viscoelastic material which performs to resist rutting, fatigue cracking, and moisture susceptibility under different loading and temperature conditions. The use of innovative and renewable pavement construction materials is inevitable due to high axle loads, rapidly increasing traffic volumes, and varying climatic conditions. This study aims to assess the effect as well as the optimum dosage of paper waste lignin for use in hot mix asphalt (HMA). Lignin from the paper industry with dosage ratios of 5, 10, 15, and 20%, was utilized to study the effect of the addition of lignin to the asphalt binder. Virgin and lignin-modified binder samples, before and after the aging process, were subjected to physical testing through penetration, softening point, ductility, viscosity and specific gravity and rheological characteristics through dynamic shear rheometer (DSR), bending beam rheometer (BBR), and rational viscometer (RV). The fractional composition was assessed through saturates, aromatics, resins and asphaltenes (SARA) fractional composition technique. Statistical analysis was also performed to find correlation of different physical and rheological parameters. Furthermore, based on optimum dosage, the performance of asphalt mixtures was studied against rutting, fatigue cracking, and moisture susceptibility. The results indicated that the addition of lignin has improved the physical properties significantly. The amount of asphaltene decreased and aromatics increased in SARA fractional analysis. Moreover, the Colloidal Instability Index (CII) has also indicated a stable structure of the binder. The rheological characteristics are improved after modification. The asphalt mixture tests revealed that addition of lignin with optimum dosage (10%) has improved the performance against rutting, fatigue cracking and moisture susceptibility. Statistical analysis indicated good co-relation among different physical and rheological parameters. This study concludes that 10% dosage is the optimum dosage that can successfully replace the virgin asphalt binder for performance of hot mix asphalt.

Synthesis and Characterization of Briquette from Carbonized Pinus Patula Saw Dust as Alternative Energy Source

This study aimed at the synthesis and characterization of briquette from Pinus patula saw dust using different binders. The effects of particle size and type of binder on the fuel qualities of the briquette were investigated. The bulk density of biomass causes handling, storage, and transportation problems that limit its large application. Densification of biomass into briquettes can solve these problems. The experimental results indicate that briquette produced from waste paper, fruit waste, cow dung, and starch flour binders has higher calorific value, higher fixed carbon, and lower ash content. Whereas, molasses and wood ash binders decreased the calorific value and fixed carbon and increased the ash content of the briquette. As a result, a maximum calorific value of 6596 cal/g, fixed carbon content of 62.6%, and ash content of 3.66% are obtained using waste paper. The calorific value of 6232 cal/g, fixed carbon of 48.74%, and ash content of 3.33% was obtained using fruit waste while the calorific value of 6194 cal/g, fixed carbon content of 59.94 %, and ash content of 5.35% was observed when cow dung is used. When starch flour is used, a calorific value of 6170 cal/g, fixed carbon content of 54.63%, and ash content of 2.63 was obtained. Therefore, waste paper, fruit waste, cow dung, and starch flour are promising binders that improve the fuel qualities of biomass briquettes.

Emerging contaminants as unintentional substances in paper and board: A case of unexpected pharmaceuticals detection in the paper recycling chain

The contamination of paper products by various chemicals has been reported on a global level, but to date, no published research has investigated pharmaceutical contamination of paper-based products. In this study, pharmaceutical analysis was conducted on 42 samples collected from various points of the recycled paper value chain in Cape Town, South Africa, which included the various grades that may be included in the manufacturing of recycled paperboard. The analysis was achieved by ultrasonic-assisted extraction of paper samples before detection by UHPLC-Q Orbitrap. Quantification limits ranged from 1.15 pg/g for ketoprofen to 46.07 pg/g for methocarbamol. Pharmaceuticals identified in newspaper samples were dexamethasone, ketoprofen, and 17β-estradiol. The latter was also detected in paper shopping bags (up to 697.49 ng/g), infant bathtub packaging (280.62 ng/g), battery packaging (137.43 ng/g), and an egg carton (170.47 ng/g). Carbamazepine was also prominent with its concentration reaching 13.02 ng/g in a vegetable box. Suspect screening tentatively identified 14 additional pharmaceuticals in paper samples, with minocycline, prazepam, and anabolic steroids appearing more prominently. This pioneering study indicated that unintentional pharmaceutical exposure had expanded beyond environmental media to consumer products.

Distribution and survival of pathogens from different waste components and bioaerosol traceability analysis in household garbage room

Household garbage rooms release abundant bioaerosols and are an important source of pathogens; however, information on the distribution and survival patterns of pathogens in different waste components is limited. In this study, a culture method and 16S rRNA high-throughput sequencing were used to determine bacterial communities, culturable pathogens, and human bacterial pathogens (HBPs). The results showed that abundant culturable bacteria were detected in all waste types, and a large number of S. aureus was detected on the surface of recyclable wastes, whereas S. aureus, total coliforms, Salmonella, Enterococcus, and hemolytic bacteria were detected in food waste and other waste. The activities of these detected pathogenic bacteria decreased after 24 h of storage but re-activated within one week. Factors affecting the emergence of pathogens varied with different waste components. Sequencing results showed that Pseudomonas, Acinetobacter, and Burkholderia were abundant in the waste samples, whereas Achromobacter, Exiguobacteriums, Bordetella, and Corynebacterium were the primary pathogens in the bioaerosol and wall attachment. The results of traceability analysis showed that bioaerosol microbes were mainly derived from raw kitchen waste (5.98%) and plastic and paper contaminated with food waste (19.93%) in garbage rooms. In addition, bioaerosols were the main source of microflora in the wall attachment, which possessed high HBP diversity and required more attention. These findings will help in understanding the microbial hazards in different waste components and provide guidance for the control and risk reduction of bioaerosols during waste management and recycling.

Sustainable integrated solid waste management for a university campus − A case study of the Federal University of Technology Akure (FUTA), Nigeria

This study provides valuable insights into the waste composition, generation rates, and opportunities for improving the current solid management practices of a university campus in Sub-Saharan Africa. Representative points were selected within the campus to collect solid waste (SW). The SW were sampled following ASTM D5231-92. The quadrant method prescribed by ASTM D 6323 was used to reduce about 150 kg of collected waste to 50 kg. The SW samples were collected in triplicates and sorted manually to determine their composition. QGIS, a geographic information system was utilized to optimize waste collection efficiency, optimal collection points, and the number of waste bins. The average daily solid waste generation at FUTA was 952.3 kg, with polythene and paper waste constituting the largest proportions at 26 % and 24 %, respectively. The waste generation rate per capita was estimated at 0.046 kg per day. Remarkably, 81 % of the waste generated at FUTA has the potential for recycling. This offers a viable potential for promoting sustainable integrated solid waste management (SISWM). The study proposes optimising waste collection points from the initial 42 to 97, considering the proximity to buildings and transportation routes. The study did not consider fluctuations in waste generation rates and composition throughout the seasons, yet the data gathered is considered adequate for this initial survey. Lack of collaboration, adequate policies, funds, infrastructure, and political will are among the impediments to SISWM in FUTA. The introduction of colour-coded waste separation bins, and assigning different colours to specific waste types, can promote proper waste disposal and facilitate recycling. Also, engaging the university community through workshops and seminars can foster such behavioural change. Collaboration with local entrepreneurs and recycling centres is another essential aspect of this paradigm shift. Such partnerships can explore innovative solutions for upcycling polythene waste and create waste-to-wealth pathways. Initial challenges of an insufficient policy framework for university- small scale enterprises (SME) engagement and the lack of business growth models could be addressed by promoting relevant skill development and motivational tasking of the existing entrepreneurship faculty. By implementing the proposed strategies and embracing circular economy (CE) principles, FUTA can reduce its environmental impact, promote recycling, and foster a culture of sustainability and entrepreneurial value creation on campus and beyond.

Experimental analysis of building components with paper and textile waste

The fast growth of building constructions industry and of the universal population is the main cause of increase in global energy consumption. Therefore, the improvement of the building envelope encourages the scientific community to investigate the use of alternative materials that assure indoor comfort conditions and at the same time promote the reduction of energy consumption by adopting energy saving strategies in the manufacturing process. The present research contribution aims to focus on the potential use of innovative building materials developed with waste paper, classified as urban non-hazardous discard component. The use of paper pulp originated from recycled paper and cardboard with the addition of textile fibers from industrial by-products was explored. Here, an effort has been made to realize sustainable insulating panel for internal use, considering different mix design and recycled components in various percentages. The research focuses on hygric, thermal, and physical performances of recycled waste based panels, measuring physical aspects as bulk porosity and bulk density and testing hygrothermal performances as the dry-state thermal conductivity, thermal diffusivity, volumetric heat capacity, and water vapour permeability. Furthermore, in order to assess the hygrothermal behaviour of the building envelope, a numerical simulation, carried out by WUFI® Plus in a Mediterranean context, was developed using as inputs the results collected from the measurement campaign in laboratory.

Regioselective oxidation of recycled cellulosic fibres for enhancement in the mechanical strength of resulting papers

AbstractThe worldwide recycling rate for paper is about 60% and there are ongoing efforts to enhance the recycling rates to 80%. The low strength of recycled paper primarily due to the contaminants in it fetches lower value to the recycled paper in the market and also limits its recyclability. The ways to circumvent the problem of contamination of paper have been addressed by adding additives. However, the use of additives increases the cost of the final recycled paper. Oxidation has been explored as an alternative to enhance the tensile strength of paper in this work as it can be used in existing paper recycling facilities without any modifications. Pulp fibres were collected from an active paper recycling mill and subjected to oxidation at various oxidation levels from 0.25 up to 1.5 mmol/g. It was found that the tensile strength of the paper increased by up to 89% with an increase in oxidation level up to 1 mmol/g and later decreased with a further increase in the oxidation level up to 1.5 mmol/g. The brightness of the paper increased by up to 3% with an increase in oxidation level up to 0.85 mmol/g and then a decrease with further enhancement in the oxidation level. The oxidized samples were also studied with infrared spectroscopy, x‐ray diffraction, electron microscopy, and optical properties to study the behaviour of the resulting material. A ring crush test and corrugating medium test were also performed on the oxidized pulp samples to establish the feasibility of the material for packaging applications.

The Approach of Waste paper Furniture from the Perspective of Mosaic Art

This paper aims to study the design method of paper home decoration from the perspective of mosaic art. The author divided the research into two parts, namely the design of the external surface of the paper furniture decoration and the internal structure of the product. Firstly, the design and development process of the project investigated the application of mosaic forms based on corrugated fiberboard and pulp. Through the classification, cutting, and splicing of corrugated paper, as well as the artificial coloring and molding of paper pulp, for the purpose of finding the visual symbols that convey mosaic art. Then, during the experiment, the structural proportions of the corrugated paper were adjusted through cutting and stacking, aiming to find ways to improve the load-bearing capacity of the corrugated paper, thereby achieving product functionality. Finally, further development was carried out by creating scale models to re-examine the proportions, structure, and stability of the design. The conclusion of the design development is consistent with the stated objectives. Paper material is functionally feasible as a home material, and combined with mosaic art, it can enhance the performance of home products at the aesthetic level and visual form. Three important discoveries were made during the project. 1) The process of applying paper pulp and corrugated fiberboard in the design of home decoration furniture. 2) The approach of using paper pulp as raw material to present mosaic art. 3) The method to improve the hardness and load-bearing capacity of paper furniture.

Development and Modification of Waste Paper Recycling Machine

Development and Modification of Waste Paper Recycling Machine

Production of recycled paper using harmless municipal sludge as a new biomass filler

Abstract Due to a shortage of resources, exploring new biomass fillers has become critical for paper making. In this study, we reported an eco-friendly strategy for fabricating low-cost and efficient recycled paper with high mechanical properties using corrugated cardboard waste paper and harmless municipal sludge (HMS). First, the characteristics of HMS, including the particle size, pH, specific surface area, organic functional groups and organic component content, were analyzed. Then, the influence of the amount of HMS on the properties of the recycled paper was studied. Finally, the strengthening mechanism of biomass filling recycled paper was discussed. The results showed that HMS, a biomass filler for recycled paper preparation, exhibited excellent physical and chemical properties, with a median particle size of 6.395 μm, a surface area of 39.974 m2 g−1 and organic functional groups. The tensile index of the recycled paper with 30 % HMS was 13.10 Nm/g, which was 16.4 % greater than that of the unfilled paper and showed better thermal stability. This excellent performance could be attributed to the uniform distribution of HMS on the fiber surface, which improved the accessibility of hydrogen bond formation between fibers. Thus, this study proved that HMS was an excellent biomass filler for producing recycled paper.

Noise Pollution Control by using Agro Waste Material

Increasing use of electrical and mechanical appliances at home and industries has created a concern for noise pollution created by them. Urbanization and heavy growth of construction work in every neighborhood further emphasize the need of new technologies for noise reduction. Noise created by different machines can be controlled either by suppressing the noise generating factors or by using the noise proofing agro materials which help to reduce the acoustic wave's energy by blocking or absorption. Maize, rice straw, and coconut fiber these agro products help to reduce the noise pollution. Newspaper waste also used as noise absorbing materials noise pollution control using agro waste involves leveraging agricultural residues to create effective sound-absorbing solutions. This abstraction encompasses the development of materials like acoustic panels, barriers, or insulation from agro waste, providing sustainable and eco-friendly methods to mitigate noise pollution in diverse settings.

Recycling of waste papers: yield and quality of the ash-derived materials

Recycling of waste papers: yield and quality of the ash-derived materials

Comprehensive characterization of unscientifically disposed municipal solid waste (MSW) in Kashmir Region, India.

Unscientific dumping of municipal solid waste (MSW) is a common practice in Kashmir. To have an environmentally friendly and sustainable waste management system, MSW was collected from nine study locations of this region. They were air-dried, then oven-dried at 105°C for 24h, segregated, and characterized for various components. The overall average organic waste was > 55%, plastic waste about 17%, inert material about 10%, paper 9%, and cloth waste 7%. The calorific value of paper and plastic wastes exhibited was 4910kcal/kg, while organic waste had a calorific value of 1980kcal/kg. The proximate analysis showed that the moisture content ranged from 16 to 29%, volatile matter ranged from 49 to 72%, ash content ranged from 0.03 to 5%, and fixed carbon ranged from 5 to 20%. In S7, the volatile matter content recorded the lowest value at 49.15%, while in S5, the volatile matter content was notably higher at 71.84%, indicating easier ignition. Further, elemental analysis revealed that the major elements in MSW were carbon and oxygen, 53% and 37%, respectively, with small traces of heavy metals with an average of 0.02% cadmium (Cd) and 0.006% lead (Pb). Moreover, field emission scanning electron microscopy (FESEM) micrographs provided confirmation that the majority of components in the MSW exhibited either partial or complete degradation, resulting in a rough surface texture. In addition, the presence of silica and other silicate groups was also detected. Fourier transform infrared spectroscopy (FT-IR) analysis revealed that the main functional groups were alcohol. In the X-ray diffraction (XRD) analysis, all the major mineral phases were detected between 20 and 30° 2θ, except for the peaks at 50-60° 2θ in S3 and S9 where catalysts such as zeolite Y and zeolite X were detected. Overall, the MSW had low moisture content but higher calorific value, making it a viable feedstock.

Study on the mechanism and law of temperature, humidity and moisture content on the mechanical properties of molded fiber products

The change of temperature, humidity and moisture content (MC) will lead to the change of mechanical properties of molded fiber products (MFP). However, it is difficult to decouple the effects of temperature, humidity and MC on the mechanical properties of MFP, and predict the mechanical properties of MFP during the use. In this study, the laws and mechanism of mechanical properties of MFP with ambient temperature, humidity and MC were studied. The results showed that the direct effect of temperature (20−70 °C) on mechanical properties of MFP was insignificant, and the mechanical properties of MFP were mainly changed by MC. The MC was related to ambient temperature and humidity, and the relationship between the three could be described by the modified Guggenheim-Anderson-de Boer (GAB) model (20−70 °C and 30 %–90 % relative humidity). With the increase of MC, the elastic modulus and fracture strain was increased and decreased linearly, the yield strength and failure strength were presented GaussAmp laws, and the failure strain was presented asymptotic regressed distribution law. Two fracture modes of MFP, brittle fracture and ductile fracture, were revealed by the scanning electron microscopy of the mesoscopic fiber structure of sugarcane bagasse molded fiber products. The mathematical models and the changes of fiber structure were verified by wheat straw molded fiber products and waste paper molded fiber products. This study was contributed to understand the effects and mechanism of the change of temperature, humidity and MC on the mechanical properties of MFP.

Preparation of superhydrophobic cellulose aerogel sponge from waste paper and its application in oil-water separation

Preparation of superhydrophobic cellulose aerogel sponge from waste paper and its application in oil-water separation

Enhanced crystalline cellulose degradation by a novel metagenome-derived cellulase enzyme

Metagenomics has revolutionized access to genomic information of microorganisms inhabiting the gut of herbivorous animals, circumventing the need for their isolation and cultivation. Exploring these microorganisms for novel hydrolytic enzymes becomes unattainable without utilizing metagenome sequencing. In this study, we harnessed a suite of bioinformatic analyses to discover a novel cellulase-degrading enzyme from the camel rumen metagenome. Among the protein-coding sequences containing cellulase-encoding domains, we identified and subsequently cloned and purified a promising candidate cellulase enzyme, Celcm05-2, to a state of homogeneity. The enzyme belonged to GH5 subfamily 4 and exhibited robust enzymatic activity under acidic pH conditions. It maintained hydrolytic activity under various environmental conditions, including the presence of metal ions, non-ionic surfactant Triton X-100, organic solvents, and varying temperatures. With an optimal temperature of 40 °C, Celcm05-2 showcased remarkable efficiency when deployed on crystalline cellulose (> 3.6 IU/mL), specifically Avicel, thereby positioning it as an attractive candidate for a myriad of biotechnological applications spanning biofuel production, paper and pulp processing, and textile manufacturing. Efficient biodegradation of waste paper pulp residues and the evidence of biopolishing suggested that Celcm05-2 can be used in the bioprocessing of cellulosic craft fabrics in the textile industry. Our findings suggest that the camel rumen microbiome can be mined for novel cellulase enzymes that can find potential applications across diverse biotechnological processes.

Exploring laccase: a sustainable enzymatic solution for the paper recycling domain.

The global advocacy of resource conservation and waste management emphasizes the significance of sustainable practices, particularly in sectors such as paper manufacturing and recycling. Currently, conventional chemical methods are predominant for paper production, necessitating the use of substantial amount of toxic chemicals. This chemical-intensive approach compromises the recycled fiber quality, generates hazardous effluent causing serious ecological threats which triggers regulatory complexities for the mills. To address these challenges modern research suggests adopting sustainable eco-friendly practices such as employing enzymes. This review aims to explore the applicability of 'laccase' enzyme for paper recycling, investigating its properties and contribution to improved recycling practices. By delving into the potential application of laccase integration into the papermaking process, this article sheds light on the limitations inherent in traditional methods surmounted within both research and translational landscapes. Culture and process optimization studies, supporting the technological improvements and the future prospects have been documented.

Effects of alkyl-ketene dimer on physical, mechanical and formaldehyde emission properties of particleboard produced with melamine-impregnated paper waste

ABSTRACT This study aimed to enhance the physical properties and the weak heat transmission of the core layer, which are the weak points of particleboard produced using melamine-impregnated paper waste (MIPW) as an adhesive. Alkyl-ketene dimer (AKD) and paraffin were used as water-repellent chemicals. MIPW was used as an adhesive, and no additional resin was used. As a result of this study, the samples’ physical properties improved with AKD and paraffin's existence. Moreover, it has been approved that AKD is more effective than paraffin in improving the physical properties of the particleboard because AKD improves ester bonding with hydroxyl groups of cellulose fibers. The usage of water repellents resulted in the improvement of internal bond (IB) properties. It was determined that the type and amount of water-repellent chemicals significantly affected the mechanical and physical properties and formaldehyde content of the produced particleboards, except for bending properties. Just the chemical type was found to be significantly effective on bending strength (BS) and modulus of elasticity (MOE) properties. Overall, the study findings suggested that AKD might be successfully utilized as a water-repellent chemical in particleboard manufacturing, while MIPWs used as an adhesive.

Characterization and thermal behavior of some types of kaolin of different origin from Northern Vietnam

Kaolin (mainly composed of kaolinite, whose chemical formula is Al2Si2O5(OH)4), serves as a versatile raw material widely used in various industries including production of ceramics, paper, paints, cosmetics, pneumatics, building materials, and hazardous waste storage. In the northern part of Vietnam, due to favorable geological conditions, there are diverse deposits of high quality kaolin of different origin and scale. Decades of research indicate the diversity of kaolin sources in the region, with special attention paid to hydrothermally altered and exchange types of kaolin, the formation of which is associated with complex processes of weathering, hydrothermal alteration and reprecipitation. The aim of this study was to characterize three different types of kaolin derived from different sources in Northern Vietnam (from weathered pegmatites, weathered felsic effusives, and hydrothermal-metasomatic altered rocks). The main focus was to analyze the thermal behavior of these samples during calcination in the temperature range from 300 °C to 1,100 °C. The comprehensive characterization was performed by X-ray diffraction (XRD), FT-IR spectroscopy (FT-IR), thermal analysis (thermogravimetry / differential thermogravimetry (TG / DTG)) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The results showed that kaolinite with particle size less than 2 μm was identified in all samples. Minor amounts of muscovite and montmorillonite are present in some samples, and pyrophyllite is present in a sample from the hydrothermally altered rocks. Kaolinite morphology in all the samples showed typical forms including hexagonal and pseudohexagonal. The main chemical constituents of the samples are SiO2 and Al2O3; in addition to these, K2O + Na2O, TiO2 and iron are present in smaller quantities. Thermal analysis allowed to reveal the formation of metakaolinite phase at temperatures around 494 °C and 507 °C in the two studied samples from weathered rocks, while the pyrophyllite-bearing sample undergoes this transition at a higher temperature of 653.8 °C. The onset of metakaolinization was observed at about 500 °C for the weathered rock samples and about 700 °C for the pyrophyllite-bearing sample. In addition, mullitization leading to the formation of mullite was evident at 1,100 °C. The study findings allow concluding that the studied kaolins can be used in traditional ceramics production.