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The carbon footprint is one of the main factors for measuring CO emissions2, this atmospheric gas represents a worldwide environmental problem. Currently, universities are making inroads into the solution through the quantification and mitigation of CO2. Academic activities and the delivery of physical documents generate high amounts of paper consumption and consequently levels of CO2, which establishes a problem. The objective is to estimate the carbon footprint of the Universidad Técnica Estatal de Quevedo (UTEQ) located in Ecuador. The methodology employed consisted of a quantification of the number of files registered in the academic system per year. The files were multiplied by an average number of sheets obtained through a survey applied to teachers. The carbon footprint was determined by multiplying the CO emission factor2 by annual paper consumption. The emissions obtained are 3.21 ton CO2 eq to 3.00 ton CO2 eq for the year 2020-2021 and 2021-2022, respectively. The virtual education implemented at UTEQ contributed to the fulfillment of climate change objectives, due to the non-emitted CO2 emissions determined in this study, an issue that is related to the achievement of a green university. [ABSTRACT FROM AUTHOR]

This study estimated paper and paperboard demand, pulpwood demand, and carbon dioxide (CO2) emissions from production of paper and paperboard through 2050 in ten Asian countries. Under scenarios of varying population, gross domestic product (GDP), and per capita paper and paperboard demand, we analyzed the relationship between economic growth and consumption of paper and paperboard. We also evaluated options to reduce CO2 emissions through increased use of black liquor, waste paper pulping, and wood chemical pulping, as well as improvements in pulp, paper, and paperboard production technology. The quadratic curve model (inverted U) for per capita consumption of paper and paperboard against per capita GDP resulted in significant regression coefficients and higher adjusted R2 values than linear and logarithmic curve models for all uses of paper and paperboard. The estimated paper and paperboard demand in the ten countries in 2050 ranged from 112% (328%) to 156% (454%) of total 2005 consumption for the world (for the ten Asian countries). Of this estimated paper and paperboard demand, China accounted for about 50% and India 20%. The estimated pulpwood demand in these ten countries in 2050 ranged from 13% (48%) to 21% (84%) of global (ten country) 2005 wood supply potential. The introduction or increase of the use of black liquor, waste paper pulping, the combination of wood chemical pulping and black liquor, and technological improvements produced CO2 reductions of 24%, 5%, 32%, and 25%, respectively, compared to 2050 emission levels in the no-measure (unadjusted) option, assuming sustainable forest management. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the prospect of integrating a combined paper&pulp mill with fuel production via biomass gasification was investigated. In the study, three different types of gasifiers (circulating fluidised bed, entrained flow and indirect gasification) and three fuel processes (dimethyl ether, methanol and Fischer-Tropsch wax synthesis) were investigated using computer simulations. The paper reports differences from the stand-alone cases and the integrated cases, using the electricity equivalence efficiency as a measure. Only 6 out of the 18 integrated cases studied displayed a positive result from integration and no obvious fuel selection that stand out as the most beneficial one, however the synthesis of dimethyl ether is, in combination with all gasifiers assessed a rather good choice, with an change in efficiency from integration ranging from −1% to 4%. Dimethyl ether is not the best choice if the electrical equivalence is to be maximised however. In this case the combination of circulating fluidised bed gasification and methanol synthesis should be pursued. The production of Fischer-Tropsch wax should according to the chosen measure not be produced; however there is an added value in the production of a non-oxygenated fuel which has not been taken into account in this particular study. All cases leads to a reduction of 0.4–0.9 kg CO2 per kg of dry biomass used in the process for fuel synthesis and the possibility to export bark is a more significant factor in this respect than which type of fuel is synthesised. [Copyright &y& Elsevier]

Abstract: The objective of the present work was to understand how the structural, surface, water vapour and gas barrier properties of wheat gluten (WG) coated paper could be influenced by the features of paper. For this purpose, a surface treated paper (TP) and an untreated paper (UTP) were compared. Penetration of WG-coating into the bulk of paper was more pronounced in UTP than TP. This led to the formation of a significant junction zone resulting in an interpenetrated structure for WG–UTP, suggesting a composite-like structure, while a bi-layer one was obtained for WG–TP. Differences in WG penetration were related to the hydrophilicity, roughness and porosity of the paper used. Even though the extent of penetration did not greatly affect the surface properties (water and oil resistance), the transfer properties (water vapour, O2 and CO2) of WG-coated papers were significantly improved when WG-coating highly penetrated: while the WG–TP behaved as a micro-perforated material, the WG–UTP behaved as WG-film. [Copyright &y& Elsevier]

Abstract: Evolutionary behavior of syngas chemical composition and yield have been examined for paper and cardboard at three different temperatures of 800, 900 and 1000°C using CO2 as the gasifying agent at constant flow rate. Specifically the evolution of syngas chemical composition with time has been investigated. Pyrolysis of the sample was dominant at the beginning of the gasification process as observed from the high initial devolatilization of the sample followed by char gasification of material to form syngas for a long period of time. Results provided the role of gasification temperature on kinetics of the CO2 gasification process. Increase in gasification temperature provided increased conversion of the sample material to syngas. Thus the sample conversion to syngas was low at the low temperature of 800°C while at elevated temperatures of 900 and 1000°C substantial enhancement of the kinetics process occurred. The evolution of extensive reaction rate of carbon-monoxide was calculated. Results show that increase in temperature increased the extensive reaction rate of carbon-monoxide. The global behavior of syngas chemical composition examined at three different temperatures revealed a peak in concentration of H2 to exhibit after few minutes into the gasification that changed with gasification temperature. At 800°C gasification temperature peak in H2 was displayed at 3min into gasification while it decreased to only 2min, approximately, at gasification temperatures of 900 and 1000°C. The effect of reactor temperature on CO mole fraction has also been examined. Increase in the gasification temperature enhances the mole fraction of CO yields. This is attributed to the increase in forward reaction rate of the Boudouard reaction (). The results show important role of CO2 gas for the gasification of wastes and low grade fuels to clean syngas. [Copyright &y& Elsevier]

Abstract: Superhydrophobic alkyl ketene dimer (AKD) layers were successfully produced on top of untreated paper surfaces by a rapid expansion of supercritical CO2 solution (RESS) process. The new method resulted in a degree of hydrophobicity, as measured by contact angles of water droplets on AKD surfaces, dramatically higher, up to 173°, compared to a conventional method consisting in melting AKD granules directly on the paper substrate, giving contact angles of around 109°. Experiments were conducted to investigate the effects of varying pre-expansion pressure (100–300bar), pre-expansion temperature (40 and 60°C) and spraying distance (10 and 50mm) on the properties of the treated surfaces. The surfaces were analyzed regarding AKD particle size, surface morphology and hydrophobicity with the aid of scanning electron microscopy (SEM) and contact angle measurements. The average AKD particle size after RESS processing was between 1 and 2μm depending upon the experimental conditions used, being slightly smaller when using higher pre-expansion pressure and temperature as well as shorter spraying distance. [Copyright &y& Elsevier]

Presents a study that investigated the influence of a modified, carbon dioxide-enriched atmosphere on the properties of paper. Types of paper used in the experiment; Properties of the paper samples treated in an atmosphere of carbon dioxide; Behavior of paper treated in a carbon dioxide modified atmosphere.

Presents a study that investigated the biodegradability and disintegration of paper product and its effects on compost quality. Effect of lignin content of materials in the low biodegradability level based on microbial degradation and measurement of carbon dioxide evolution; Degradation of nylon bags; Results of data analysis.

• Supercritical CO 2 displaces water from alum, wastewater, and paper sludge. • Multistage dewatering increases the degree of dewatering. • The expanding CO 2 blows out the water during decompression. Supercritical CO 2 (sCO 2) displaces water from wastewater, alum, and papermill sludge. The sCO 2 appears to enter the sludge matrix through viscous fingering through the entrained water. Because the water removed far exceeds the solubility of water in sCO 2 , it must be displaced by the sCO 2 rather than dissolved out. Adding a small amount of soap to the sludge converts some of the bound water into free water, which can then be displaced by sCO 2. Application of the sCO 2 in multiple stages greatly enhances dewatering as compared to a single stage process. Approximately 70, 70 and 85% of the initial water can be removed from alum, wastewater and paper sludges, respectively, through a five-stage process. Staged application of sCO 2 doubles the efficiency of water removal over a single-stage process of the same duration. It is proposed that when the sCO 2 entrained in the sludge is decompressed between stages some of the water is explosively displaced by the expanding CO 2. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Cellulose-based solutions can improve environmental performance of food packaging. • Food products require specific barrier functions from cellulose-based packaging. • Eco-design enables quantifying environmental performance and identifying trade-offs. • Fulfilling the barrier requirements for food product packaging is crucial. This short communication describes the climate change impacts of using cellulose, and more precisely cellulosic fiber-based materials, in food packaging, representing current and emerging industrial state of the art technology, without specific reference to current scientific advances. First, the different types of cellulosic fiber-based packaging materials, which can be used to replace fossil-based packaging materials, are presented for flexible and rigid applications. The focus is on technological solutions with packaging properties that enable the protection of commonly sold food products. The manufacturing processes associated with these cellulosic fiber-based materials is described and the environmental impact assessment of 4 selected case studies presented: stand-up pouches, flexible flow wraps, frozen or chilled food trays, and molded pulp lids. A simplified eco-design Life Cycle Assessment (LCA) was then performed to compare each solution with its fossil-based counterpart. Differences and similarities between the various cellulosic solutions have been identified. Furthermore, the assessment confirms that cellulosic fiber-based materials have reduced environmental impacts as compared to fossil-based counterparts, if a similar packaging weight is obtained. Indeed, all impacts of plastics are between 3 and 5 kg CO 2 eq/kg, while all impacts of cellulosic fiber-based materials are below 1.5 kg CO 2 eq/kg. [ABSTRACT FROM AUTHOR]