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In this study, we examined the effects of cationic starch（CS） as a reinforcing agent and a binary reinforcement system with nanocellulose（NC） on the reinforcement of recycled paper produced from old corrugated cartons（OCC）. To determine an appropriate dosage of CS, we examined the effects of CS dosage on the performance of OCC recycled paper. Further, using the optimal dosage identified, the effects of its addition on the performance of OCC recycled paper were investigated by adding NC to form a binary reinforcement system. The strengthening mechanism of the CS-NC binary composite system was examined based on a combination of Fourier transform infrared spectroscopy（FTIR）, field emission scanning electron microscopy（SEM）, and thermogravimetric（TG） analyses. The results revealed that CS（1.5%） had the best enhancement effect on OCC recycled paper, with burst, tensile, and tear strengths of hand sheets being increased by 17.62%, 18.18%, and 22.93%, respectively, and air permeability being decreased by 28.55%, compared with the control group. Furthermore, we found that combined treatments with 1.5% CS and NC all enhanced the performance of OCC, with optimal effects being observed when NC was added at a 1% concentration. Compared with the improvements obtained with the sole addition of 1.5% CS, the combined treatment was found to increase the burst, tensile, and tear strengths of OCC recycled paper by a further 5.11%, 11.54%, and 13.46%, respectively, and reduced air permeability by 12.58%. The findings of FTIR analysis revealed that CS can bind to pulp fibers, and that the addition of NC increases the number of hydrogen bonds, thereby facilitating a tighter bonding between fibers. Moreover, SEM observations of the microscopic morphology of the surface of recycled paper indicated that the CS-NC binary system can contribute to a more compact and tighter inter-fiber bonding. In addition, the TG analysis results revealed that by enhancing fiber cross-linking, the CS-NC treatment could increase thermal degradation of the remaining residue of OCC recycled paper to up to 600°C. Our findings in this study indicate that treatment with a combination of CS and NC can significantly enhance the performance of OCC recycled paper. We believe that our results would provide a valuable reference for the repeated recycling of OCC. [ABSTRACT FROM AUTHOR]

As pro-environmental behaviors in business are advocated, recycling process has become a hot topic in the supply chain management. Besides the traditional wholesales and retail for new products, manufacturers would like to recycle and reprocess used products with consideration of production costs and pressure from environment protection. This paper considers the recycling process implemented by manufacturers themselves or entrusted to retailers to implement. A two-period model is established to discuss the optimal recycling and pricing strategies for manufacturers and retailers under both active return and passive return. The results show that the manufacturers and retailers are always better off in active return than that in passive return. The decision that manufacturers participate to the recycling by themselves or entrust it to retailers depends on the return rate and the collection cost. Numerical simulations and sensitivity analysis are implemented to demonstrate our results and illustrate the effect of each parameter on the optimal strategies. [ABSTRACT FROM AUTHOR]

Recent trends in waste management have initiated interest in recycled materials for sound absorption applications. The present paper studies the possibility of paper sludge to be recycled as material for sound absorption applications. Paper sludge (PS) is the water treatment waste, produced during paper production. Two different methods were studied to produce paper sludge and slaked lime composite acoustic panels for sound absorption applications at low and mid-frequencies. The sound absorption coefficient of paper sludge composite panels is measured in an impedance tube using the two-microphone method. The samples produced with different methods showed different behaviours of sound absorption. The primary method to produce showed acoustic asymmetry in the vertical direction of the samples, and it was considerably fragile as well. An improved method to produce PS composite panels was proposed in this paper. Using this method, homogenous and robust acoustic panels were obtained. [ABSTRACT FROM AUTHOR]

Wastes from recycled paper industry (WRP) was hydrothermally carbonized to remove impurities to produce alternative biofuel. The chlorine behaviors during hydrothermal carbonization (HTC) and the fuel properties of the generated hydrochar were evaluated. The degradation of lignocellulosic components improved free -OH bond and small free cellulosic fragments facilitating dechlorination. Meanwhile, dechlorination process stimulated degradation of biomass. The carbon content and density of WRP were improved by HTC resulting in high heating value increasing from 5044.40 MJ/m³ to 17,004.88 MJ/m³. Pollutants emission from hydrochar combustion would be effectively controlled because of the removal of sulfur and chlorine. Hydrochar enjoyed higher ignition temperature and average combustion rate while lower burnout temperature, indicating that the combustion range has been narrowed, thus improving the combustion efficiency. The increase of HTC temperature facilitated hydrochars combustion and reduce energy consumption during hydrochar combustion. Mild HTC operating conditions (220 °C for 90 min and 240 °C for 60 min) were supposed to effectively improve the combustion intensity with stability meanwhile reached the highest dechlorination efficiency. These results evidence the feasibility of converting WRP to clean biofuel via HTC. [ABSTRACT FROM AUTHOR]

The performance of an asphalt mixture does not only rely on its engineering properties. Yet, the service characteristics of an asphalt mixture do play an important role on the durability of pavements. This study was conducted to evaluate the effect of different aggregate types (granite and limestone) and the incorporation of recycled paper mill sludge (RPMS) on mixtures behaviour in terms of workability and compaction energy index (CEI). The effect of RPMS incorporation on the leaching potential was also assessed. A test was evaluated through the toxicity characteristics leaching procedure (TCLP) to identify the leaching behaviour of heavy metals with a possibility to contaminate the nearby water sources. Next, a surface morphological analysis was also conducted through the Scanning Electron Microscopy (SEM) to assess the relationship of fillers addition to the optimum binder content and water absorption. In this study, RPMS was used at rates of 0.5% and 1%. Based on the TCLP's results, the leaching potential of RPMS incorporated mixture was addressed and proven to be less than the standardised requirements. The addition of different percentages of RPMS into limestone and granite asphalt mixtures had resulted in the increment of optimum binder content; however, still lower than control samples. Whereas their small increment in the combined water absorption percentage are relatively same to the control samples. The workability indices of asphalt mixtures peaked upon the usage of 0.5% RPMS but slightly reduced at 1% RPMS but nevertheless remained higher than the control specimen. This is due to the ability of RPMS reduce the surface tension, hence enabling less energy for compaction. The 0.5% RPMS addition was found to be the optimal content required to obtain a better service performance of asphalt mixture during mixing and compaction processes. [ABSTRACT FROM AUTHOR]

Wastes from recycled paper industry (WRP) was hydrothermally carbonized to remove impurities to produce alternative biofuel. The chlorine behaviors during hydrothermal carbonization (HTC) and the fuel properties of the generated hydrochar were evaluated. The degradation of lignocellulosic components improved free -OH bond and small free cellulosic fragments facilitating dechlorination. Meanwhile, dechlorination process stimulated degradation of biomass. The carbon content and density of WRP were improved by HTC resulting in high heating value increasing from 5044.40 MJ/m3 to 17,004.88 MJ/m3. Pollutants emission from hydrochar combustion would be effectively controlled because of the removal of sulfur and chlorine. Hydrochar enjoyed higher ignition temperature and average combustion rate while lower burnout temperature, indicating that the combustion range has been narrowed, thus improving the combustion efficiency. The increase of HTC temperature facilitated hydrochars combustion and reduce energy consumption during hydrochar combustion. Mild HTC operating conditions (220 ℃ for 90 min and 240 ℃ for 60 min) were supposed to effectively improve the combustion intensity with stability meanwhile reached the highest dechlorination efficiency. These results evidence the feasibility of converting WRP to clean biofuel via HTC. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper recycles and reuses sucker rod carbon fiber composite by microwave technique. The high temperature dielectric parameters of sucker rod carbon fiber composite were tested with the perturbation technique of cylindrical resonator. The structure and performance of the recovered carbon fiber samples were characterized by testing methods like scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffractometer (XRD). The results show that: the carbon fiber of sucker rod is good at absorbing microwaves. During microwave pyrolysis, the heating rate can reach 359.46 (°C/min), which greatly shortens the processing time. In addition, the microwave technique does not affect chemical bonds and functional group types, and the resulting recycled carbon fibers can be recycled well. [ABSTRACT FROM AUTHOR]

Today the print quality of digital printing techniques has improved and is considered satisfactory and competitive to analogue techniques for certain graphic products. Satisfactory print quality mostly depends on the interaction of ink and printing substrate where ink penetration has an important role. Namely, the ink penetration affects the parameters that describe the print quality together with visual appearance of print density and mottling. Therefore, it is important to select an adequate printing substrate for each printing technique. Awareness of environmental problems related to the shortage of wood raw materials has led to an increase in the use of recycled printing paper and in particular the implementation of new alternative sources of cellulose fibres instead of virgin wood fibres in the papermaking process. In this research the emphasis is precisely on defining the influence of ink penetration into laboratory papers made of triticale pulp on the final print quality. The laboratory printing papers were obtained by mixing triticale pulp with pulp from recycled fibres in three different portions. Papers were thereafter printed by ultraviolet (UV) inkjet printer and the ink penetration within laboratory papers with and without straw pulp was analysed using two methods of ink penetration analysis (microscopic/spectroscopic). The influence of ink penetration on the final print quality was observed and analysed based on several quality parameters (optical ink density, mottling and colorimetric values). These results confirmed that triticale pulp in laboratory papers provides equal print quality compared to laboratory papers made only from pulp from recycled fibres. [ABSTRACT FROM AUTHOR]

This paper develops a novel paper additive for effectively recycling old corrugated container (OCC) by functionalizing nanocellulose (NC) with diethylenetriaminepentaacetic acid (DTPA) and chitosan (CS), and investigate the reinforcing mechanisms and effect of the developed additive on the physical properties of recycled OCC pulp handsheets. The tensile, tear and burst index, air permeability, tensile energy absorption (TEA), and drainage performance of the recycled OCC handsheets are examined. Fourier transform infrared FTIR) spectroscopy, thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) are used for the chemical and microstructure characterization of both NC based additives and paper from recycled OCC pulp. The results show that functional groups on the NC based additive, such as carboxyl, amino and hydroxyl groups, can bond with the hydroxyl groups on the recycled OCC fibres to generate a chemical bond. This leads to an increase in the crosslinks and bonding area between the fibres, which increases their tensile strength and improves their recycling rate. SEM shows that the paper with NC based additives had tighter inter-fibre bonds and smaller paper pore structure. Addition of 0.3% NC-DTPA-CS additive results in optimal properties of the recycled OCC paper with an increase by 31.64%, 22.28% and 36.6% of tensile index, tear index, burst index respectively, and the air permeability decreases by 36.92%. [ABSTRACT FROM AUTHOR]

This study suggests focused in user-centered design which are new separate discharge system that must recycle in paper materials. I searched cases in Korea’s current law and regulation in recycling disposal guidelines and already succeed cases in each city that are Asia, Europe, and North America. Suggesting focused in user-centered design of ID(Identification) separate discharge system due to user’s good participations, feedbacks of participation’s results, and well-organized in awarding. This system consists of visual individual’s ID(Identification) that are stickered in only used bag. User must recycle in separate discharge system only used bags, and results must visualized in each user and rewards to user. This separate discharge system is meaning to stimulate user’s good participations. [ABSTRACT FROM AUTHOR]

The wettability of the paper surface is greatly affected by the wettability of the pulp fibers. We conducted this study in order to understand the relationship between the wettability of a single fiber of recycled pulp and the strength of recycled paper, as well as the inter-fiber bonding strength. The contact angle was determined from a series of photographs of the pulp fiber and the water silhouettes at the point of contact. The contact line and profile history were continuously photographed in every 1 s after the initial contact. The recycled softwood kraft pulp fibers were clearly much less hydrophilic than the original fibers, regardless of whether the fibers had been bleached or not. The contact angle of the original chemi-thermomechanical pulp fiber was much higher than that of the original softwood bleached kraft pulp fiber. Furthermore, increased number of recycling decreased the contact angle of the chemi-thermomechanical pulp fiber. The Page equation was used to evaluate the strength contributions of single fiber and fiber–fiber bonding to tensile strength of paper. As a result, an increase in weakness factor of fiber–fiber bonding strength was obtained for the recycled softwood kraft pulp handsheet. On the other hand, the weakness factor of the original chemi-thermomechanical pulp handsheet decreased with recycling. In addition, the weakness factor of fiber–fiber bonding strength and the contact angles of the provided softwood bleached kraft pulp fibers bore a proportional relationship to each other. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the physical characteristics of the biomass crop Erianthus arundinaceus as a bedding material for broiler and to compare it with existing bedding materials. Three physical characteristics were evaluated: the water absorbability, the water‐holding capacity, and the cushioning property. E. arundinaceus, shredded to five different particle sizes, was compared with sawdust, which is a typical bedding material used worldwide, and three alternatives: recycled paper, rice husks, and bagasse. E. arundinaceus absorbed water 5.0 to 10.2 times its weight, and water absorbability increased with decreasing particle size. E. arundinaceus held water around twice its weight regardless of the particle size. The cushioning property of E. arundinaceus tended to improve with increasing particle size. For each physical property, the total average value of the E. arundinaceus samples was compared with the values of other bedding materials. The water absorbability of E. arundinaceus was significantly higher than that of sawdust, recycled paper, and rice husks (p <.01). The water‐holding capacity of E. arundinaceus was significantly higher than those of sawdust, recycled paper, rice husks (p <.01), and bagasse (p <.05). The cushioning property of E. arundinaceus was significantly higher than those of sawdust and recycled paper (p <.01). When E. arundinaceus had an average particle size of less than 2.33 mm, it exceeded sawdust in all physical characteristics, suggesting that E. arundinaceus could replace sawdust as a favored bedding material. Our observations of surface structures revealed that the stem pith of E. arundinaceus has a spongy structure, which may contribute to its high water absorbability and water‐holding capacity. Moreover, the outermost layer of the E. arundinaceus stem appears to function like a leaf spring, contributing to the high cushioning property. [ABSTRACT FROM AUTHOR]

Pressure Sensitive Labels (PSLs) can be found on the wide range of products, from food items and beverages to perfumes and other household products. Given their prevalence, there is a clear initiative to reduce the proportion of synthetic polymer facestock in favor of biodegradable materials. The design of PSL is becoming more and more attractive, so it is necessary to examine the quality of the printed line on biodegradable facestock materials, and to investigate whether an equal amount of applied ink gives a satisfactory result as on synthetic polymers which are commonly used. Yellow ink lines of various widths and orientations were printed on seven different commercially available PSLs, three of which are fiber based with high content of recycled paper and agro-industrial by products. Study showed that the lines printed on environmentally friendly PSLs can compete in quality (width, raggedness, blurriness, contrast, fill and darkness) with those printed on polyethylene. [ABSTRACT FROM AUTHOR]

Even though the recycling of paper and paperboard is quite successful when compared to the recycling of other resources, there are many things to improve. Recovering the used paper and paperboard without contamination and sending it back to the papermill that produced it would enhance the recycling potential and efficiency of recovered fiber resources. Close collaboration between a paper and packaging company and a logistics company has made a big improvement in recycling and achieved the circular economy of fiber resources. It is time to find better ways to collaborate, thereby improving our capability to keep our planet green. [ABSTRACT FROM AUTHOR]

Anaerobic co-digestion of sludge from recycled pulp and paper industry (RPPS) with vinasse effluent from alcohol distilleries (VW) was performed under mesophilic conditions (37 °C) at laboratory scale, using one-liter continuous stirred tank reactors (CSTRs). The physicochemical parameters were monitored during the process. The average pH and alkalinity were 7.7 and 1000 mg CaCO3 Kg−1, respectively, indicating that the process is working well without the risk of acidification. The methane yield and biodegradability of this mixture were determined. The methane yield was about 112 (NmL CH4 g−1 VS added) and biodegradability reached 73%. Nevertheless, in monodigestion of RPPS, the methane yield was 94 (NmL CH4 g−1 VS added) and biodegradability 65%. The anaerobic co-digestion of (RPPS) with (VW) at a proportion of (70:30) improved methane production by 16% and biodegradability by 11%. Bioenergy recovery from industrial (RPPS) is promoted by co-digestion with (VW), and the removal efficiency of 73% indicates the performance of the process adopted. A kinetic study was performed using five models Richards, modified Gompertz, Logistic, Cone, and first order. The results show that Richards' was the most appropriate model for adjusting methane production from (RPPS) and (VW) co-digestion. [ABSTRACT FROM AUTHOR]

The article discusses the importance of the use of recycled paper to ensure sufficient supply of printing paper in the graphics art industry amidst the increase in demand. Topics inlcude the incompatibility of some printing technologies with paper recycling systems, the global market demand for paper materials, as well as the paper requirements in regions like Europe, North America and Asia.

Enzyme cocktails can alter the lignin and hemicellulose content in wood cell walls, improving the bleaching process during pulp production and offsetting the need for toxic chemicals. In this study, brown pulp was biobleached with a mixture of crude fungal extracts rich in xylanase and laccase, respectively produced from Aspergillus tamarii Kita and Trametes versicolor on waste materials. The optimal conditions for biobleaching were a mixture of xylanase and laccase crude extracts (1 to 2 v/v), at a temperature of 36 °C and a pH of 5.5. The treated brown cellulose pulp showed a reduction in the Kappa number by 1.83 points, representing an efficiency of 20.3%. In addition, the brightness increased by 4.65 points in comparison to the control. Hence, studies involving the application of the standardized cocktail during the hydrolysis of lignocellulosic residues, e.g., barley residue and sugarcane bagasse, led to the formation of 85 g/L and 25 g/L of reducing sugars, respectively. Moreover, the standardized cocktail caused greater deinking of the recycled paper pulp. [ABSTRACT FROM AUTHOR]

Process baths used for electropolishing and pickling of stainless steel have become increasingly contaminated with heavy metal ions over time. There is still lack of research on the neutralization of this type of technological wastewater with high concentrations of metal ions and containing complexing compounds, which significantly hinders their effective treatment. The aim of this paper is to study how the selected methods of heavy metals removal will affect the quality of the treated, industrial post-galvanic sewage from pickling and electropolishing of chromium-nickel steel on a laboratory and technical scale. The research used sodium sulphide or a decomplexing agent based on organic sulphur to neutralize wastewater containing triethanolamine or glycerol. Treatment of electropolishing wastewater poses a challenge. Nevertheless, wastewater with glycerol is easier to neutralize than those containing triethanolamine. In the industrial scale the use of a decomplexing agent is necessary to achieve the required nickel values in the wastewater after treatment below 1 ppm. Even in the case of high concentrations of nickel ions in raw wastewater, the neutralization process of the wastewater originating only from pickling alone was effective. The search for effective methods of neutralization of mixed wastewater is especially important in industrial conditions, where it is not always possible to completely separate these two types of sewage. The paper also presents the results of the composition of post-neutralization sludge, which may be useful in planning further management and disposal of this type of waste. [ABSTRACT FROM AUTHOR]

The organic fraction (mainly food waste) is typically the most abundant of the separately collected waste streams. The research aims at investigating the influence of different types of collection bag on the environmental performances of the food waste management chain in Italy. A comparative life cycle assessment (LCA) between two alternative systems based on paper or bioplastic collection bags was carried out. It included the collection bags manufacturing and distribution, their use at the household, the transportation of collected food waste and its subsequent anaerobic digestion, including the valorisation of useful outputs and the management of residues. The two systems were modelled mainly with primary data related to the current management system and to tests performed on bags. The LCA was performed with two different modelling approaches applied in the environmental product declaration (EPD) system and in the product environmental footprint (PEF) studies, respectively. In the scenario representing the average conditions, higher environmental impacts are shown by the use of bioplastic bags compared to paper ones with the EPD approach (+257%/+576%). With the PEF approach, the differences between the two systems are lower (−55%/+133%). Moreover, paper bags could allow for further impact reductions assuming a decrease of the food waste collection frequency, allowed by higher weight losses and a lower generation of leachate and odour during the household storage. [ABSTRACT FROM AUTHOR]

Converting biomass into jet fuel involves more than the core chemical process. The overall process includes the logistics of harvesting and transporting the biomass, handling and preparing the material for processing, and processing and disposal of waste. All of these activities contribute to cost. Controlling cost involves more than developing efficient process chemistry. Choice of feedstock also has a significant impact on process economics. We consider chemical conversion of paper from municipal solid waste as a feedstock for the production of jet fuel and diesel. Paper has a significantly higher cellulose content than raw lignocellulosic biomass such as corn stover, so it requires less pretreatment to convert it into hydrocarbons than lignocellulosic biomass. Our techno-economic analysis showed that the cost of converting paper waste into jet fuel is about $1.00/gal less than jet fuel produced from corn stover. Although the cost of recycling paper into jet fuel is less than producing it from corn stover, the process is not competitive with petroleum. We estimated a minimum selling price of $3.97/gal for paper-derived jet fuel. Our sensitivity studies indicated that the biggest economic obstacle is the cost of cellulose hydrolysis. Direct hydrogenation of paper to sugar alcohols combined with increased economy of scale could make recycling paper jet fuel competitive.

The use of mulch contributes to the reduction of water consumption and weed infestation in strawberry cultivation. Recycled paper, being biodegradable, has great potential to replace plastics. Thus, the objective was to evaluate the water consumption and agronomic performance of strawberry subjected to different wetted areas and mulches. The wet areas tested were 40% (WA40) and 70% (WA70) imposed by a drip irrigation system. The different types of mulch were: white polyethylene (WHP), black polyethylene (BLP), recycled paper (REP) and no mulch (NM). BLP, REP and WHP mulches promoted the same weed control. The number of fruits per plant, fruit length, fruit yield, and water productivity did not differ for the factors wetted area and types of mulch. Higher fruit mass and diameter were found in the WA40 treatment, while the mulches favored only fruit mass. Thus, fruit yield showed no difference, and only water consumption differed between the wet areas and between the types of mulch. Strawberry water consumption was higher in WA70. In relation to fruit waste, it was found that the WHP and BLP mulches provided higher values than REP and NM. Thus, the recycled paper, combined with a wet area of 40%, is recommended as a mulch in strawberry production.

The aim of this study is to compare laserjet printing and inkjet printing properties on recycled papers. In the study, we recycled reference papers prepared in accordance with the INGEDE 11p standard. After recycling the papers, we produced test papers in the laboratory environment and examined the physical and optical properties of the obtained papers. We applied calendering process at 100 oC temperature and 20 bar pressure on the obtained test papers. After this process, we printed trigromy color measurement scales with inkjet and laserjet printers on the test papers obtaine Finally, using the spectrophotometer, we determined the printing properties of both print types. When we examined the results, we determined that in most of the printability parameters, laserjet had a superior performance and was a more usable printing system. For example, while the inkjet cyan density value is 0.94, the laserjet is 1.05. While M + Y trapping value was 28.23 in inkjet, it was 92.20 in laserjet. For example, we found the Gloss value as 2.53 in inkjet and 4.23 in laserjet. While inkjet cyan print chroma value is 44.03, it is 48.09 in laserjet. In addition, we determined that laserjet printing reached a wider area as a color gamut. Based on the color measurement results of both printing types, we have determined that the printability of recycled papers is reasonable. We have determined with experimental results that laserjet printing produces better quality prints in a short time, especially in the office environment. [ABSTRACT FROM AUTHOR]

Cellulose based nanomaterials have the great potential to be applied to paper as bulk additive or coating material to improve overall final properties, especially in secondary fiber. In the present work, the effect of applying different kinds of cellulose nanofibrils (CNF) to papers obtained from recycled fibers using size press on physical, mechanical and barrier properties was investigated and compared with the sole use of starch as coating material. The coating process of CNF was carried out by the addition of size press grade starch to coating suspension. As a cellulose source, wheat straw was evaluated and CNF was obtained through oxidative and enzymatic pretreatments. Results indicate that starch/CNF suspension improves the overall paper properties. As a result of the deposition of coating suspension contains of 4 % wt. periodate-oxidized CNF onto paper surface, tensile and burst indices of papersheets increased as 52.2 % and 194.4 %. Significant decreases were observed in air permeability as 69.8 %. Compression tests also have been conducted to evaluate papersheets end-use properties. In comparison to the other pretreated CNF, due to is lower viscosity, applying periodate-oxidized CNF as size press significantly increased the mechanical properties of the papers fabricated from the recycled pulps. [ABSTRACT FROM AUTHOR]

Copyright of Iranian Journal of Wood & Paper Science Research is the property of Research Institute of Forests & Rangelands and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Paper industry produces large volumes of wastewater causing environmental pollution due to containing high levels of organic matter. In the present study, native yeasts of one of the paper and cardboard recycling industries wastewater were isolated and identified, and their efficiency in the wastewater bioremediation was investigated. In this experimental study, after sampling, the yeast strains of the wastewater were isolated and identified. After preparing the yeast suspension, experiments were performed on the main sample of the wastewater and the modified samples with pH 5, 6, and 7, dilution of 25% and 50%, and incubation time of 48 and 96 h. The efficiency of these yeasts in removing chemical oxygen demand (COD) was also investigated. The results showed that this industrial wastewater contains high levels of turbidity and COD. Two types of yeast, including Candida glabrata and Candida albicans, were identified. The optimal pH for C. albicans was 6 and for C. glabrata was 5. According to the results of the experiments, COD removal efficiency by these yeasts was 71% and 81.8%, respectively, at incubation time of 96 h and dilution of 25% of the wastewater at optimal pH. It seems that according to the characteristics of these isolated yeast species and their ability to remove COD, they can be considered as an economic and eco-friendly option for the treatment of the mentioned industrial wastewater. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Developing environmentally friendly barrier coatings as an alternative to petroleum-based polymer packaging is a challenge. Cellulose nanofibres (CNF) films have exhibited great potential as water and gas barrier layers. Recycled paper was multi-layer coated with three commercial CNF (mechanical (M-CNF), TEMPO (T-CNF) and carboxymethylated (C-CNF)) using two metering systems (wound rod and blade micrometer) and two drying methods (tension-free contact drying and air drying). The coatability and rheological behaviour of the CNF suspensions were analysed. The gas, water and grease barrier properties of the CNF coated papers were determined and compared with the results of paper coated with cationic starch. The three CNF suspensions and the starch suspension were successfully coated using both metering systems. In the multi-layer coating, air drying yielded higher coat weights than contact drying, and the difference was more noticeable in M-CNF and T-CNF coated samples. A lack of uniformity observed in CNF coatings increased with the number of coating layers. M-CNF coated samples had a whitish surface with a uniform appearance, but coating was insufficiently compact to provide barrier properties. T-CNF coating exhibited a cracked surface and consequently provided no barrier properties. Drying stresses caused breakage of T-CNF coating, which could be explained by the drop in apparent viscosity at much lower rheological shear stresses in the T-CNF suspension. C-CNF showed successful coatability and provided barrier properties to paper with both metering systems and drying methods. Air permeance decreased considerably and the water wettability of the paper decreased by 60% compared to the reference paper, even with a single coating layer (about 1 g·m−2). In addition, a greaseproof paper (grease resistance >1800 s and kit no >10) was obtained with multi-layer C-CNF coating. Although water vapour permeability at 90 % RH and 20 °C decreased slightly with a single layer of CNF coating, higher amounts of CNF did not improve this parameter. • Evaluation of CNF coatability in metering and drying systems employed in papermaking • Air stream drying led higher CNF coat weights in multi-layer application. • Cracked coating under drying stresses was related to rheological behaviour of CNF. • Carboxymethylated CNF can be used as pre-coating to improve paper barrier properties in papermaking. • A greaseproof paper by multi-layer carboxylated CNFs coating could achieved [ABSTRACT FROM AUTHOR]

Biomass can be used as an energy source to thermochemical conversion processes to biocrude production. However, the supply and dependence on only one biomass for biocrude production can be an obstacle due to its seasonality, availability, and logistics costs. In this way, biomass waste and agroindustrial residues can be mixture and used as feedstock to the hydrothermal co-liquefaction (co-HTL) process as an alternative to obtaining biocrude. In this sense, the present paper analyzed the biocrude yield influence of the co-HTL from a quaternary unprecedented blend of different biomasses, such as sugarcane bagasse, brewer's spent grain (BSG), sludge from a paper recycling mill (PRM), and microalgae (Chlorella vulgaris). In this way, a simplex lattice design was employed and co-HTL experiments were carried out in a 2000 mL high-pressure stirred autoclave reactor under 275 °C for 60 min, considering 15% of feedstock/water ratio. Significant effects in each feedstock and their blends were analyzed aiming to increase biocrude and biochar yield. It was found that the addition of microalgae is only significant when considered more than 50% into the blend with BSG and PRM sludge to increase biocrude yield. • Unprecedented blend (microalgae, sugarcane bagasse, BSG, and PRM sludge) in co-HTL. • Highest biocrude yield of 51.7% using microalgae as the only feedstock. • Second-highest biocrude yield (29%) for BSG and PRM sludge (synergetic interaction). • BSG and PRM sludge can complement co-HTL feedstock in low microalgae availability. • E RoI higher than one for 50% of microalgae, 25.8% of BSG, and 24.2% of PRM sludge. [ABSTRACT FROM AUTHOR]

The change in the dimension (Thickness Swelling; TS) was found to be high, at high boric acid content for boards made from Office paper/Newspaper (O/N) and Office paper/Old Corrugated Container (O/C) types. However, the boards made with 10% boric acid exhibits higher Modulus of Rupture (MOR) values than boards made with 5.0% boric acid. The highest value of MOR was found as 7.93 MPa with the addition of 10% boric acid with Newspaper/Old Corrugated Containers (3:1 by weight) mixtures. The Modulus of Elasticity (MOE) of the boards generally decreased with increasing boric acid content from 5% to 10% in furnishes. The Office paper/Newspaper had the highest MOE among the all formulations and considerable higher than standard value of 600 MPa. However, the highest value of MOE was found as 735.63 MPa with the mixture of 3:1 (by weight) proportions of Office paper/Newspaper proportions. The similar results were observed for Internal Bond (IB) properties of boards, as like MOE. While in general, increasing boric acid content from 5.0 to 10%, negative effects on IB properties of boards. It was also realized that the boric acid content and fiber proportions effects various level on thermal properties (thermal conductivity; TC). The boric acid had usually provided higher thermal resistance, but the difference between fiber proportions and fiber types consisting of boric acid was important. However, the lowest TC value of 0.1455 W/mK was found the boards made from only old corrugated containers fibers with 10% BA content. The sound absorption values of boards made from secondary fibers show a sound damping that it was steady increase up to 1600 Hz and then decreasing. It could be realized that the sound absorption properties of boards were generally better than that of in lower frequencies.It was also realized that the boric acid content and fiber proportions effects various level on thermal properties (thermal conductivity; TC). The boric acid had usually provided higher thermal resistance, but the difference between fiber proportions and fiber types consisting of boric acid was important. However, the lowest TC value of 0.1455 W/mK was found the boards made from only old corrugated containers fibers with 10% BA content. The sound absorption values of boards made from secondary fibers show a sound damping that it was steady increase up to 1600 Hz and then decreasing. It could be realized that the sound absorption properties of boards were generally better than that of in lower frequencies.

The uses of natural dyes are getting popularized due to the increased awareness regarding the toxicity of many chemical colorants. The chemical colorants are being replaced by the natural colorants for the various industrial applications. The plant-based natural colorants are considered eco-friendly and toxic free. In the present study, we report a natural dye from the heartwood of Caesalpinia sappan suitable for paper based packing materials. This forms the first report on the study of natural dye obtained from the heartwood of C. sappan on paper material. The extracted dye had a good photostability and able to make imprints on recycled paper bags. Moreover, a significant inhibition of bacterial growth was observed at a higher dye concentration of 100 μg mL−1 against P. aeruginosa which was higher than the standard antibiotics. Growth inhibition was also observed in case of B. subtilis (22 ± 0.17 mm) and K. pneumonia (21 ± 0.53 mm) at 100 μg mL−1. The dye could be used in making medicated packing materials and have many other bio-potential which was validated through in silico toxicity analysis. The application of such natural dyes in paper material value addition will help in a cleaner and sustainable process during paper recycling. [ABSTRACT FROM AUTHOR]

The present research aims to shed light on the effect of activated sludge (from a paper mill) and nanochitosan on the physical and strength properties of recycled pulp. Firstly, activated sludge was treated with 3% acetic acid for 30 min and then placed in a beaker for 90 min at 100 °C. Then, the ingredients were mixed and refined with recycled newsprint pulp in different proportions (0, 5, 10, and 15%). Finally, 2% nanochitosan was optionally added. Test specimens were prepared according to TAPPI standards with a basis weight of 120 g/m2, and their physical (water absorption) and strength (tear strength, tensile strength, burst strength, and ring crush test) properties were measured and compared. The results showed that with the increase of untreated activated sludge in recycled paper pulp, the indicators of tear resistance, ring crush test, and burst strength decreased and water absorption increased. Strength properties increased and water adsorption decreased when adding activated sludge treated with 3% acetic acid. Through the addition of nanochitosan to activated sludge treated with acetic acid, a significant increase in strength properties and a decrease in water absorption were observed. [ABSTRACT FROM AUTHOR]

Due to the increasing accumulation of wastes around the world, the demand for sustainable products is increasing. Paper is a commonly disposed of material that can pose problems even when it is recycled. The concept of using cardboard (CB) as a material for furniture production has been around for many years, but CB furniture does not last long. This study examined the feasibility of using post-consumer recycled paper to produce paper-based boards for furniture design. Cardboard (CB) and office paper (OP) were the main post-consumer materials that were used. The CB and OP were mixed with polylactic acid (PLA) and limestone. The boards were made at a temperature of 200 °C and pressed at a pressure of 3.5 N/mm2 using a single opening hydraulic press. The physical and mechanical properties were tested according to the European standards for woodbased panels. Tests that are critical for furniture parts, such as the modulus of rupture (MOR), the modulus of elasticity (MOE), the internal bond, the screw withdrawal resistance, the thickness swelling, and the water absorption were examined. The paperboard samples exceeded some of the requirements for the general use of boards for interior fitments (including furniture) for use in dry conditions (Type P2) and for non-load bearing boards for use in humid conditions (Type P3). [ABSTRACT FROM AUTHOR]

To determine the occurrence of mineral oil hydrocarbons (MOH) in food contact papers in China, and to investigate the potential sources of MOH contamination, a total of 159 food contact papers and raw materials were analysed by off-line solid-phase extraction-gas chromatography flame ionisation detection (SPE-GC-FID) and a GC-MS method. The migration of MOH from food contact papers into Tenax, olive oil or 50% ethanol under the worst foreseeable conditions of use was determined. The results indicated that the occurrence of MOH in China is of a potential health risk concerning the migration of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) which were detected in 82.6% and 50.4% of samples, respectively. Migration of MOSH from 47.9% of samples was higher than 2 mg/kg and migration of MOAH from 32.2% samples exceeded 0.5 mg/kg in case of the worst foreseeable condition of use. The highest mean migration of MOSH and MOAH were found in packaging papers for long-term storage (more than 6 months), with mean migration of 91.2 mg/kg and 1.4 mg/kg, respectively. Migration of MOH from printed paper was considerably higher than that of unprinted paper, validating previous findings that the printing ink is the predominant source of MOH contamination in food contact papers. Migration of MOH from paper bowls used for packing instant noodles was relatively low, suggesting the internal hollow layer may be acting as a functional barrier that could block the transfer of MOH (up to C28) through the gas phrase, even though the outer layer was made from recycled paper. High concentrations of MOSH and MOAH were also detected in de-foamers, adhesives and rosin sizing agents, indicating that the MOH contamination caused by the use of raw materials and additives should also be taken into consideration. [ABSTRACT FROM AUTHOR]