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Mitigation of global warming, energy security and industrial competitiveness urge the energy-intensive pulp and paper industry (PPI) to transform energy use practices. This study investigates how the PPI has responded to the need for the energy transition in the 2000s. Finland and Sweden as forerunners of energy-efficient operation and decarbonization of the PPI are used as target countries. Understanding of changes in energy consumption is complemented using decomposition analysis (Logarithmic Mean Divisia Index Method) and the energy efficiency index approach. Analysis of companies’ investments in energy technologies is used for explaining changes in energy production. Evidence of significant development towards the more sustainable operation of the PPI was found. Energy consumption per produced unit has decreased, i.e., energy efficiency has improved. Fossil fuels have been partially replaced with bio-based alternatives. Thus, the CO2 intensity has decreased substantially. The generation of renewable electricity has increased in both countries. Examples of Finland and Sweden indicate that the PPI has great potential to contribute to CO2 emission reduction worldwide in the future as energy efficiency can be further improved, and the share of fossil fuels can be decreased increasing the use of biofuels and self-generated green electricity at least in kraft pulp mills.

This paper aimed to modify the ignitability of the bagasse paper by using talc powder, 1,3-di-aniline-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane, and nanocellulose crystal. The formation of cellulose nanocrystals (CNCs) was detected using transmission electron microscopy (TEM), X-ray diffraction (XRD). Thermal analysis as thermal gravimetric analysis (TGA) of the specimens recorded the improvement of the highest % of ash residue at 750 °C compared to the untreated one. The shape of the flame spread was studied. The ignition properties were studied for the untreated and treated specimens by limiting oxygen index (LOI) and flame chamber (UL/94), which recorded enhancing compared to the untreated specimen. This improvement was recorded either by measuring the mechanical properties (tensile strength, burst strength, elongation, and elasticity) of the specimens. The current article showed that the treated specimen was recorded the highest values compared to the untreated one in all physical, mechanical, and ignition properties, so these treatment paper sheets may be used as fire-retardant packaging materials.

Biodiesel, as a green fuel, acts as a potential candidate to supplement conventional fossil fuels. This research study targets green environment (using biodiesel) and clean environment (reduce wastewater) by producing biodiesel through oleaginous biomasses (Yarrowia lipolytica, Metschnikowia pulcherrima and Lipomyces starkeyi) grown on pulp and paper industrial wastewater. Batch culture studies were explored for the potential feedstock of the oleaginous organism by the synthesis of single cell oil and fatty acid methyl ester (FAME) yield. Response surface methodology (RSM) was used to design the optimal experimental matrix and identify the optimal process conditions that enhance the FAME yield. To determine the inherent characteristics of the growth of oleaginous biomasses on the industrial wastewater, a data-driven adaptive neuro-fuzzy inference system (ANFIS) is implemented. Y. lipolytica strain cultured shown high biomass concentration of 32.36 g/l with biomass productivity of 5.39 g/l/d was considered for further scale-up for the transesterification process. Results indicated that the maximum yield of 0.48 (g-biodiesel/g-lipid) was obtained under the 2.5 g of lipid dosage with 0.02 g/ml of catalyst concentration by constant stirring at 70 °C. The optimum conditions to achieve maximum FAME yield of 1.154 g/g was obtained at 2.485 g, 70.87 °C and 0.021 g/ml for lipid dosage, temperature and catalyst concentrations, respectively.

Paper mulberry, a fast-growing and vigorous plant, is a potential substrate for producing lignocellulosic bioethanol and an important renewable alternative to fossil fuels. In order to improve the economic feasibility of ethanol production from paper mulberry, H3PO4/H2O2 pretreatment was selected as the most suitable pretreatment method that could produce the highest glucose concentration (131 g/L) compared with other pretreatments (73.2–89.3 g/L) at high solid loading. Whereafter, the final solid loading of H3PO4/H2O2 pretreatment was significantly increased to 40% (w/v) without any decrease in the final glucose concentration. Finally, a novel Fed-nonisothermal-simultaneous saccharification and fermentation was constructed using H3PO4/H2O2 pretreated paper mulberry, which bypassed the inhibition caused by paper mulberry solid and high temperature on the traditional simultaneous saccharification and fermentation, improving ethanol concentration (63.9 g/L), ethanol productivity (1.33 g/L/h) and ethanol yield (0.160 g/g-biomass) by 30.4%, 30.4% and 30.1%, respectively, compared to those obtained from SSF (simultaneous saccharification and fermentation) process. Thus, we have opened up a novel way to produce ethanol or other biofuels using the paper mulberry as an outstanding alternative substrate.

Paper wastes form the major biodegradable fraction of the municipal solid waste. One of the best ways to treat paper wastes is using them as a feedstock for biomethane production through anaerobic digestion (AD). However, the AD characteristics, kinetics, and energy potential of different types of paper wastes are not clear. In this study, four kinds of typical paper wastes including corrugated board (CB), office paper (OP), tissue paper (TP), and magazine paper (MP) were used as feedstocks to produce biomethane at different volatile solids (VS) organic loading (OL). TP had a high cellulose content and showed high biomethane potential, while the lowest was obtained by CB, possibly due to its high lignin content. Kinetic analysis showed that Cone and modified Gompertz model could fit the biomethane production process well. Energy potential analysis revealed that biomethane yield, electric generating efficiency, and electricity price were the principal factors accounting for the profitability of biomethane production project treating paper wastes. Overall, paper wastes could be a promising feedstock for biomethane production, because paper wastes not only had high biomethane yield and biodegradability that exceeded many kinds of organic wastes but also could be continuously supplied for AD plants without the influence of seasonal changes.

In society, there is widespread and growing acceptance of the value of cooperation between industry and universities being collaborative Research and Development (R&D) domain and industrial policy the fuel of knowledge-based economies. In this paper, different domains of cooperation between the University and Industry as well as their generated benefits for each partner are identified. These benefits have been assigned to each domain of cooperation, showing a large number of benefits associated to collaborative R&D. Leading us to make a statement - collaborative R&D is the key cooperation domain for sustainable long-term university-industry partnerships. Suggestions are given about how to continue this research study.

Bioethanol production using paper wastes seems a promising approach towards sustainable energy, but mainly hindered by hazardous ink. Therefore, in our experimental plan various methods were applied for the deinking of waste newspapers, laser printed papers and examination papers. A newly designed paper pulper reduced the pulping time from 6 h to 2 h. Cellulase (15 FPU/g) from Aspergillus oryzae MDU-4 was found effective for the deinking of newspapers, whereas laccase isozymes (150 U/g) from Ganoderma lucidum MDU-7 along with 2 mM HOBt was preferred for the ink removal and degradation from the examination papers. Ozonation in the presence of Tween-80 was found to be efficient in the removal of toxic toners used in laser printing papers. The biologically and physically deinked papers, studied with the help of SEM, TEM, FTIR, and XRD analysis revealed significant changes in the chemical and surface structure. Moreover, the saccharification of deinked papers with the help of an enzymatic consortium of Trichoderma citrinoviride MDU-1 resulted in 305 mg/g, 377 mg/g, and 409 mg/g release of sugars from the newspaper, examination paper, and laser printed paper, respectively. Finally, the enzymatic hydrolysates fermented with Saccharomyces cerevisiae NCIM-3640 produced 3.35 g/L ethanol, with 40.85% ethanol yield.

Abstract writing is a very important since it is the piece of formal writing which should attract the attention of the reader and make him/her read the rest of the paper. Thus, it must be clear, concise, coherent, and powerful enough to attract the reader and provide him/her with the key information about the content of a research paper. All university students have to write an abstract in English in their qualification papers. However, non-native students of English usually have difficulties in writing an abstract in English. For example, the Czech students lack formal writing skills in English since the skill of formal writing is not developed enough in their native language, i.e. Czech. Therefore, the aim of this article is to discuss the use of an off-line scaffolding tool, which can help students develop an abstract in English, as well as to demonstrate how this tool can be incorporated in the whole Course of Practical English taught at the Faculty of Informatics and Management of the University of Hradec Kralove in the Czech Republic. The application was developed for students as support to a face-to-face class instruction, which proved to be insufficient in teaching students how to write an abstract in English. The application reflects the structure and sentence functions of the abstract and provides students with a model abstract, as well as with additional formulations. Overall, the application was designed with the purpose to enhance student’s skill of writing an abstract in English, as well as to lead students to successfully complete the task by making the application user-friendly - easy-to-use, accessible and transferrable as far as the knowledge is concerned. The application aims to enhance students’ autonomous learning by tailoring the content to their specific needs and making it accessible anytime and from anywhere.

Biohydrogen and biomethane production via two stage sequencing system from paper mill effluent (PME) was evaluated to enhance its COD reduction. Heat-shock pretreatment of anaerobic sludge at 90 °C for 15 min was chosen to obtain a mixed microbial inoculum for dark fermentative hydrogen production. The effect of initial pH (5, 6 and 7) on the efficiency of hydrogen fermentation at different concentrations of substrate (3, 5 and 7 g-COD/L) was investigated, which the maximum hydrogen yield was obtained at initial pH 5. After that, the effects of substrate concentration (3, 5, 7, 10 and 15 g-COD/L) and fermentation temperature (37 and 55 °C) were investigated on the hydrogen production yield. The efficiency of dark hydrogen fermentation for all substrate concentrations was higher at 55 °C. The hydrogen production was enhanced as substrate concentration increased up to 5 g-COD/L, but then it was reduced, and the optimum hydrogen yield of 38.8 mL H2/g-CODinitial was obtained at substrate concentration of 5 g-COD/L at 55 °C. The highest hydrogen (35.1 mL H2/g-CODinitial) was obtained at 5 g-COD/L and 55 °C and the highest methane (553.8 mL CH4/g-CODinitial) was obtained at 3 g-COD/L and 37 °C. Maximum COD reduction of 88.1% was obtained in two-stage sequencing dark fermentation/anaerobic digestion system at 3 g-COD/L and 37 °C.

This paper evaluates the environmental impacts of different alternatives for handling of sludge from paper and pulp mills in Sweden, using Life Cycle Assessment (LCA). The common practice of incineration of biosludge with energy recovery followed by landfilling of ash (System A) was compared with the alternative of digesting sludge anaerobically to produce biogas using different digestate residue management options. The digestate produced from anaerobic digestion (AD) was assumed to be incinerated for heat energy recovery in System B or pyrolyzed for biochar production in System C to be mixed with forest soils. The impact categories considered in this work are climate change, non-renewable energy use, mineral extraction, aquatic ecotoxicity, carcinogens and non-carcinogens. The LCA results demonstrate that the two proposed systems significantly reduce the environmental impacts of biosludge management relative to incineration. An 85% reduction in the aquatic ecotoxicity impact is achieved in System C, due to the reduced mobility of heavy metals in biochar relative to ash. System C, on the whole, outperformed the other two, leading the authors to the recommendation that the use of pulp and paper mill biosludge in biogas-biochar production systems is preferable to merely recovering energy from it.

Unprinting of paper can reduce multiple life-cycle stages in the recycling of paper to yield significant environmental impact. Laser-unprinting has been demonstrated for uncoated paper but causes significant damage to coated paper. This work explores a scalable optical (non-laser) process for unprinting coated paper. Printed coated paper is exposed to pulsed broad-spectrum Intense Pulsed Light (IPL) from a xenon lamp and the toner is then removed by dabbing gently with an ethanol wipe. While black toner is easily unprinted, unprinting of colored prints (red, blue, green) is best realized by incorporating an initial overprint of black toner. An unprinting throughput on the order of mm2/s is achieved. Three distinct regimes of unprinting are identified based on the extent of toner removal and damage of the paper. The optical properties of the unprinted paper, characterized via UV–Visible spectrophotometry, are correlated to these regimes to understand the potential for in-situ optical process monitoring. Scanning Electron Micrography and Fourier-Transform Infrared Spectroscopy are performed to understand the underlying mechanisms that govern the occurrence of the different unprinting regimes. Further, the potential impact of the developed approach on recycling of paper is discussed in the context of the capabilities of current optical unprinting approaches and the potential elimination of life-cycle stages in conventional paper recycling.

The recycling of waste paper has been an effective way to achieve the environmental-friendly growth of papermaking industry. Focusing on the mixed-pulping process which has been generally employed, to ensure the required properties of the deinking pulp (DIP) and minimize the purchase cost of waste paper, an intelligent model scheduling the mixing ratio of waste paper was developed in the study. Primarily, driven by the field data of mixing ratio of waste paper and DIP properties, the prediction models of DIP properties were developed by SVM, GA-SVM, and BP-NN algorithms. Subsequently, based on the best prediction model, the scheduling model for the mixing ratio of waste paper was set up by NSGAII algorithm. The experimental results showed that, based on the obtained best BP-NN prediction model of DIP properties, the developed NSGAII scheduling model for the ratio of waste paper could achieve excellent scheduling results under the rigorous constraints and multi-objective. Compared with the previous study, the developed prediction and scheduling models in this study reduced the purchase cost of waste paper by 2.16%, and improved the acceptable proportion of DIP property from 56.07% to 100%.

Industrialization and urbanization are the key drivers to threaten the environmental quality and natural resources. Traditionally, pulp and paper industry has been highly reliant on forest based resources for its escalation. Shortage of forest based raw materials, strict environmental regulations and policies have compelled the industry to seek for alternate raw materials for its production. Mills are now focusing on exploring the potential of different agro wastes such as cereal straws and bagasse etc. In present research, sugarcane trash, one of the most abundant agro residues in India, was investigated for its capability in pulping and bleaching. Chemical characterization of sugarcane trash showed that it contains 40.4% cellulose, 33.2% hemicelluloses, 17.4% lignin and 6.45% ash content with 2.76% silica. To cook sugarcane trash with soda pulping method, 14% alkali charge, 15 min time and 162 °C temperature was found to be optimum and pulp of kappa no. 19.8 was prepared that exhibited good strength properties. Bleaching of pulp was carried out using elemental chlorine (Cl2), hypochlorite and chlorine dioxide (ClO2) based sequences. Replacement of Cl2 with ClO2 has significant impact on strength properties and effluent characteristics. Oxygen delignification stage was incorporated prior to ClO2 that resulted in improved optical properties of pulp with noticeable reduction in wastewater load. This paper elaborates the need of using sugarcane trash in paper mills with environment friendly pulping and bleaching processes to combat with the problem of waste management, wastewater load reduction during bleaching and substitute for wood based raw materials in papermaking.

The effects of paper waste (PW) ratio on biogas production by two-stage thermophilic anaerobic co-digestion (coAD) of food waste (FW) and PW, two main components of organic fraction of municipal solid waste, were evaluated in lab-scale continuously stirred tank systems with semi-continuous feeding. Four PW ratios (0, 20, 40, and 50%) were studied in the test. The experimental results showed the two-stage thermophilic coAD could operate stably after an adjustment period at all PW ratios. Although the increase of PW ratio decreased methane content, production and yield, reaction rates of four AD steps, it could increase the methane production of substrate when the FW was fixed. The pH, total volatile fatty acids, total alkalinity, and total ammonium of the sludge in the second stage of AD, also decreased with the increase of PW ratio in the test. The change of the substrate's organic composition, increase of carbohydrate and decrease of protein and lipid, were the main reason for the decrease of methane content, production and yield and changes of the second stage sludge characteristics. An apposite PW ratio (PW-20%) could enhance the degradation of matters (TS, VS and TCOD).

This paper examines the mechanical properties and durability of recycled aggregate concrete (RAC) containing 100% coarse recycled concrete aggregate (RCA) and industrial by-products. The by-products, including waste paper sludge ash (PSA), fly ash (FA), silica fume (SF), and metakaolin (MK) of different proportions (5%, 10%, 15%) in RAC, were used in two methods: replacement and addition methods. The use of by-products (mineral admixtures) to mitigate the low quality of RAC was demonstrated through experimental outcomes in this study. The addition of industrial by-products was presented as a promising alternative for the addition of more Portland cement in RAC to enhance RAC's quality. The results showed that the strength and durability of RAC containing mineral admixtures in the addition method were higher than the addition of more cement or the replacement method. Notably, PSA considerably improved the mechanical properties of RAC at an early age, and it substantially improved the resistance of RAC to acid and sulfate attacks. At 90 days, FA and MK improved mechanical properties of RAC greater than SF and PSA did. Among combinations, the proportions of by-products in RAC of 5% PSA, 10% SF, 15% MK and 15% FA can produce the highest performance of RAC with 100% coarse recycled concrete aggregate (RCA).

The paper drying process has the highest level of energy consumption in the pulp and paper production process. Analysis and optimization of the energy system during the paper drying process is critical for improving the energy efficiency of the entire paper mill. In the existing model for the paper drying process, the solution requires accurate boundary conditions such as the air temperature and humidity of the pocket area and the cylinder surface temperature, which are very difficult to obtain in the papermaking process. This can result in significant deviations between the model solution and the actual production process. This paper focuses on the single-tier dryer cylinder-based paper drying process that has been widely used with high-speed papermaking machines in recent years. A mathematical model is proposed based on real-time data. The verification via industrial production demonstrates that the proposed model is reliable for the paper drying process. Based on the simulation results, two optimization operations have been proposed. The energy consumption decreases from 1.51 t steam/t paper to 1.44 t steam/t paper, 4.6% of the steam and 1.26 × 106 RMB can be saved for a medium-scale paper mill with the annual production capacity of 105 t paper.

Pulp and paper industry is one of the high priority sectors that generates large amount of solid (sludge) and liquid (paper mill effluent) wastes. Making use of this huge quantity of paper mill sludge (PMS) in an environment friendly manner is challenging and cost involving. Similarly the present wastewater treatment strategies based on physical and chemical methods encounter certain serious setbacks including secondary pollution generation with expensive mode of abatement processes. The present study aims at a “waste treats waste” strategy for the bioremediation of paper mill effluent in fluidized bed reactor (FBR) using another waste of the same industry, PMS as immobilizing matrix for Planococcus sp. TRC1, a wastewater bacterial isolate. This study simultaneously explores this isolate for the yellowish orange pigment it produces (2.3 ± 0.2 mg/gm of dry bacterial biomass) and characterizes it as a member of the pharmacologically important carotenoid pigment family via UV-Vis spectrophotometry, TLC, FT-IR and 13C NMR. The antioxidant potential of this pigment was studied by DPPH assay (IC50 = 33 ± 0.4 μg/ml) and H2O2 assay (IC50 = 147.4 ± 2.2 μg/ml). In FBR, the PMS immobilized bacteria showed removal of phenol, lignin, colour and COD from the effluent by 96%, 74%, 81% and 85% respectively after 60hr of treatment. The experimental data on immobilization fitted well with pseudo second-order (R2 = 0.955) and Freundlich adsorption isotherm (R2 = 0.996) models. The alterations in PMS before and after bacterial immobilization, as revealed by SEM and FT-IR, depicted the success of PMS as immobilization matrix. Phytotoxicity (90% seed germination) and mutagenicity studies confirmed that the treated effluent was substantially less toxic than its raw state. This study highlights a novel utilization possibility of PMS in an eco-friendly and economic way as immobilization matrix for Planococcus sp.TRC1 for paper pulp mill effluent treatment along with production of carotenoid pigment from this potential bacterial isolate as value added product.

Microbial fuel cell is a promising technology to harvest energy from wastewater, and effective anode catalysts are essential for its applications. In this study, zero-dimension nitrogen-doped carbon dots, as biocompatible efficient modifiers, were synthesized and decorated onto the carbon paper surface to prepare microbial fuel cell anode. The as-fabricated nitrogen-doped carbon dots decorated carbon paper anode was able to enhance electricity generation and efficient wastewater treatment. It was found that the as-fabricated electrode had a high hydrophilicity, which was favorable for the microbial immobilization. Compared with the carbon paper anode, the biofilm on the as-prepared anode was almost twice of thickness. After introducing nitrogen-doped carbon dots, the extracellular electron transfer process from the microorganisms to the anode was enhanced. The microbial fuel cell with the as-developed anode generated a remarkable power output of 0.32 mW, 1.1 times higher than that of the raw carbon paper anode with same measurement area. Moreover, 16 sRNA pyrosequencing analysis shows that the quantity of Pseudomonas on the electrode increased by ∼40%, which also promoted the electron transfer rate by excreting mediators like phenazines or phenazine derivatives. This work developed a new approach to design microbial fuel cell anode material and fabricate a high-efficiency and environmentally friendly anode for electricity generation from wastewater.

The world paper industry produces a great amount of industrial solid waste that undergoes a treatment process that can be either primary, secondary, or tertiary, in order to adapt the waste for correct disposal. The paper manufacturing industries search for the best way to dispose of their wastes, generally in landfills, but there are few studies proving the effectiveness of such measure from the environmental, technological and economic points of view. Knowing the characteristics of this waste and understanding the treatment process it is submitted to are fundamental issues to manage it and comply with environmental demands. The purpose of this paper is to perform a chemical, mineralogical, thermal, morphological, physical and environmental characterization of the paper and pulp industry wastes, in order to assess alternatives for their adequate disposal, such as controlled landfills, sanitation, incineration, and sea dumping. It was observed that the material presents physical, chemical, and morphological features that indicate the possibility of reusing it in other production chains, such as the ceramic industry, besides being classified as non-hazardous wastes. Furthermore, disposal in sanitary landfills presents advantages in environmental and technological terms.

This study estimates efficiency in energy utilization at firm level and feasible energy saving target of the pulp and paper industry in India. For this analysis, data is extracted from prowess database for a panel of 67 major pulp and paper producing firms over the period of 2003–04 to 2013–14. We employed radial and non-radial variants of data envelopment analysis to assess the feasible energy saving target with the current level of output. Particularly, we employed slack-based method with variable returns to scale as a flexible and pragmatic approach to performance analysis. Results reveal no significant improvement in the energy efficiency level of the firms over the study period and show vast energy saving potential. Results of slack-based measure of energy efficiency show the feasible energy saving potential of 40%. Further, size of the firm, age and financial performance are important factors that influence energy efficiency. Therefore, this study recommends special attention to the paper industry while implementing energy efficiency programme. We also reviewed four major policies for industrial energy efficiency improvement initiated by Bureau of Energy Efficiency, India.

Black liquor, an industrial waste, also generally called spent liquor is a promising feedstock for production of bio-carbon due to its high lignin and energy contents. Mild processing conditions and sustainable resource utilization can drive commercial utilization of this industrial waste. A novel oxidative procedure using hydrogen peroxide as a green liquid oxidant at room temperature for processing of paper recycling neutral sulphite semi-chemical spent liquor was established and evaluations were carried out for its efficiency. Standard hydrothermal carbonization was carried out for comparing bio-carbon production qualitatively and quantitatively using the same spent liquor. The oxidation procedure was performed at room temperature using 5% of H2O2 followed by washing in diluted sulfuric acid (0.15 N) while hydrothermal carbonization was performed at 250 °C. The bio-carbon produced were similar in terms of ash percentage and ranged from 1.25 ± 0.05 to 1.48 ± 0.05% for oxidation method and from 1.11 ± 0.03 to 1.45 ± 0.04% for hydrothermal carbonization. The carbon contents for the oxidation method ranged from 60.54 to 61.50% and 66.81–67.31% for hydrothermal carbonization while higher heating values ranged from 25.32 to 26.11 MJ/kg and from 28.68 to 29.34 MJ/kg respectively. The mass yield ranged from 29.98 to 31.88% by the oxidation, while it was 15.02–16.08% by hydrothermal carbonization.

The global demand for bio-plastic particularly polyhydroxyalkanoate (PHA) have been increased in the last few decades as a substitute of petrochemical-based plastic. Utilization of waste paper, the primary constituent of municipal solid waste (MSW), as a carbon source for polyhydroxybutyrate (PHB) production is not only an alternative, environmental friendly route of waste management but also helps to valorize the waste. In this study, hydrogen peroxide pretreated waste paper saccharification has been optimized using central composite design (CCD). The maximum hydrolysis (88.18%) occurred at paper loading 5.0 g/L, agitation 242 rpm, working volume 20%, cellulase 49.82 U/g, β-glucosidase 20.9 U/g and hemicellulase 29.5 U/g. PHB synthesis and biomass accumulation by xylose-utilizing Burkholderia sacchari using waste paper hydrolysate were studied using different nitrogen sources and carbon to nitrogen (C/N) ratios. Maximum PHB and dry cell weight (DCW) occurred with ammonium sulfate and a C/N ratio of 20. The highest biomass (3.63 g/L), the maximum PHB accumulation (44.2%) and the maximum reducing sugar utilization (92.1%) were observed after 48 h of cultivation using diluted hydrolysate. The physicochemical properties of the extracted PHB were compatible with the standard PHB. Hence, the waste paper could be exploited as a renewable feedstock for the sustainable production of PHB.

It is necessary to preserve rumen fluid for transport from slaughterhouses to the pretreatment facilities for use in treating lignocellulosic biomass. In this study, we investigated how the preservation of rumen fluid at various temperatures affects its use in hydrolysis of waste paper. Rumen fluid was preserved anaerobically at 4, 20, and 35 °C for 7 days. The number of protozoa and fibrolytic enzyme activity after preservation at 4 °C were significantly higher than that after preservation at either 20 or 35 °C. Waste paper was subsequently treated with preserved rumen fluid at 37 °C for 48 h. Preservation at 20 °C remarkedly decreased the hydrolysis of waste paper. Xylanase activity in rumen fluid preserved at 35 °C increased during the treatment, which enhanced the solubilization of waste paper as comparable to the control and preservation at 4 °C. Pretreatment of waste paper with rumen fluid preserved at 4 °C showed that the fluid retained high fibrolytic activity, and reduced the loss of organic carbon as substrate for methanogens. Our results suggest that preservation of rumen fluid at 4 °C is most suitable for efficient pretreatment and methane fermentation of waste paper.

This work demonstrates a novel-type paper-based solid electrolyte (PBSE) and its application in Al-air battery, which is targeted for miniwatt applications. Benefited from the solid-form electrolyte, a liquid-free operation of the Al-air battery is realized, eliminating the potential leakage hazard and therefore improving the battery practicability. The PBSE is prepared by impregnating gel electrolyte into porous cellulose paper, followed by a solution casting process to solidify the gel. The as-prepared PBSE can either be used in mechanical rechargeable Al-air batteries, or be integrated into single-use flexible Al-air batteries. Currently the PBSE can achieve a moderate battery performance with a peak power density of 3.8 mW cm-2 and an Al specific capacity of 900.8 mA h g-1. Properties of the PBSE can be further improved by a comprehensive parametric study on its fabrication parameters, such as gel concentration, casting temperature, casting time, porosity and pore size of paper substrate, etc.

Small companies encounter difficulties to adapt to new markets with a sustainable perspective. The subject of this article is a paper transformation company which has been eager to develop the organic farming market by developing a new plant support. Alternatives made from plant fibres or plastics exist, such as jute and polypropylene. The main difficulty of this project was to ecodesign a paper product with a multicriteria approach. The factors considered have been divided into two categories. Firstly, the environmental impacts calculated according to the Life Cycle Assessment methodology (on raw material extraction, manufacturing and end-of-life) are summarised. Secondly, the characteristics of the product are discussed in regards to these results and sustainability questions as part of the interpretation phase. Finally, ways of improvement of the LCA methodology to improve the study in terms of geographical representativeness and societal considerations are discussed.

Cyber-physical systems theory offers a powerful framework for modeling, analyzing, and designing real engineering systems integrating communication, control, and computation functionalities (the cyber part) within a natural and/or man-made system governed by the laws of physics (the physical part). New methodological developments in cyber-physical systems theory are required by traditional application domains such as manufacturing, transportation, and energy systems, which are currently experiencing significant and – to some extent – revolutionary changes to address the needs of our modern society. The goal of this position paper is to provide the cyber-physical systems community, and especially young researchers, a clear view on what are research directions worth pursuing motivated by the challenges posed by modern applications.

The production of human-generated wastes is increasing with the rise in the world’s population. Under this scenario, sustainable management of large quantities of waste is becoming an increasingly challenging task. The present study carried out the anaerobic co-digestion of food waste (FW), human feces (HF), and toilet paper (TP) to evaluate its potential for use in the on-site treatment of household organic wastes. The biochemical methane potential (BMP) was determined for these wastes and their mixtures, confirming the effective methanation of each substrate and its mixtures, with FW showing significantly higher BMP than HF or TP. Response surface analysis of the BMP data successfully produced two models describing the effect of the substrate mixing ratio on the overall methane yield and the synergistic effect of co-digestion (in terms of methane yield). The obtained models revealed that methane yield and the synergistic effect of co-digestion are influenced in different ways by variations in the substrate mixing ratio. Importantly, the effect of interactions between individual substrates is not substantial in magnitude regardless of the substrate mixture composition (synergy index close to 1). This indicates that FW, HF, and TP can be co-digested without compromising the overall methane yield (i.e., no antagonistic effect) at any desired substrate mixing ratio, which makes the application of co-digestion in the field more flexible. The overall results suggest that anaerobic co-digestion is a feasible means for the on-site treatment and valorization of mixed FW, HF, and TP, the major household organic wastes.

A kind of wood pulp fiber paper (WPFP) was proposed as candidate for the matrix of desiccant wheel. Silica gel was coated on WPFP by impregnation method and the corresponding coating ratio was obtained and analyzed. Then the thermal conductivity, pore structure and adsorption/desorption performances of WPFP coated with silica gel were tested and analyzed. The results indicated that the WPFP has high coating ratio for silica gel due to its hydrophilic characteristic. The thermal conductivity of WPFP coated with silica gel after the first coating increases obviously compared with raw WPFP and reaches to 0.1292 W/(m⋅K). In addition, the WPFP coated with silica gel after the first coating has high specific surface area and its maximal adsorption quantity for water vapor can be 0.240 g/g. Finally, the DCOP of the desiccant wheel using WPFP as matrix obtained by numerical simulation can be 1.75 under the given working condition that the temperature of regeneration air is set as 90 °C and the inlet condition of process air is set as 34.3 °C and 56.2% RH. It is indicated that the desiccant wheel using WPFP as matrix can meet the requirement of air dehumidification and save energy by 7.35% simultaneously.

One of the benefits of Internet of Vehicles (IoV) is improved traffic safety and efficiency, for example due to the capability to share vehicular messages in real-time. While most of the vehicular messages only need to be shared by nearby vehicles, some messages (e.g., announcement messages) may need to be more broadly distributed, for example to vehicles in a wider region. Finding a single trusted entity to store and distribute such messages can be challenging, and vehicles may not be inclined to participate (e.g., generation and distribution of announcement messages) unless they can benefit from such participation. In addition, achieving both security and privacy can be challenging. In this paper, we propose a blockchain based secure data sharing system to address the above challenges in an IoV setting. Specifically, in our system, announcement messages are stored using blockchain. To encourage/incentivize participation, vehicles that faithfully broadcast the announcement messages and/or contribute to the block generation will be rewarded by some cryptocurrency. Our system is also designed to be privacy-preserving and realizes both priori and posteriori countermeasures.

Energy recovery from small and medium scale waste thermal treatment facilities in the municipalities of Japan is challenging, owing to low power generation efficiency and high economic demands. Gas Engine (GE) generation is considered an efficient resource utilization method in these facilities. In this study, new and consistent feedstock, Refuse Paper and Plastic Fuel (RPF), and wood pellets were tested in an air-blown Fluidized Bed Gasifier (FBG) for syngas utilization in a GE. With temperatures ranging from 700 to 940 °C and varying Equivalence Ratios (ER) of 0.3–0.5, some of the most important product gas characteristics were analyzed, including the Lower Heating Value (LHV) and tar concentration levels. Gas composition results revealed that the concentration tendencies varied for the product gases CO, H2, and hydrocarbons, depending on the feedstock type, whereas the same tendencies were observed for CH4 and tar concentrations. Through the ER range, the LHV of product gas for RPF and wood pellets was 3.4–5.9 MJ/Nm3. Tar concentrations decreased to 2.5–14.0 g/Nm3-dry as the ER was raised. The optimal ER for LHV performance in GE generation was approximately 0.4 for RPF and wood pellets, and remaining tar concentrations were about 5.0 g/Nm3-dry at the gasifier exit.

Graphene paper (GP) is more feasible to be integrated as a heat spreader than monolayer graphene due to its controllable size and moderate reduction in thermal transport properties. In this work, we fabricated and characterized GP to understand its thermal transport properties based on thermal bridge method combined with transient electro-thermal technique. The thermal conductivity of GP exhibits a highly temperature dependent property from 637 W/mK at room temperature to 757 W/mK at 80 °C, which is contrary to the trend of monolayer graphene. The increasing thermal property can be partially ascribed to the morphological and inner-structural change of the composite at elevated temperatures. Surface roughness is found to be reduced by 30% from atomic force microscope imaging. This feature is beneficial for many industrial applications such as the cooling film in smartphones. The implementation of GP is further verified in a smartphone to simulate the heat-dissipation performance. The results show that GP with temperature dependent properties exhibits much better cooling performance than conventional cooling films such as copper film.

Success management can bring valuable contributions to improve project results and stakeholders’ relationships. However, the success management process must be explicitly integrated into project management approaches, guides and methodologies (such as PMBOK, PRINCE2 or PM2), which is not currently happening. The purpose of this position paper is to discuss the need and importance for this integration and to present a first proposal on how this can be operationalized. To support the position, the methodology of the European Union PM2 was used. The result of the integration demonstrates that it is possible to advance management and raise the level of project success.

Background In Software Engineering (SE), conference publications have high importance both in effective communication and in academic careers. Researchers actively discuss how a paper should be organized to be accepted in mainstream conferences. Aiming This work tackles the problem of generalizing and characterizing the type of papers accepted at SE conferences. Method The paper offers a new perspective in the analysis of SE literature: a categorization scheme for SE papers is obtained by merging, extending and revising related proposals from a few existing studies. The categorization scheme is used to classify the papers accepted at three top-tier SE conferences during five years (2012–2016). Results While a broader experience is certainly needed for validation and fine-tuning, preliminary outcomes can be observed relative to what problems and topics are addressed, what types of contributions are presented and how they are validated. Conclusions The results provide insights to paper writers, paper reviewers and conference organizers in focusing their future efforts, without any intent to provide judgments or authoritative guidelines.

The industrial solid waste generation and its stockpile disposal have major environmental consequences. These consequences could be minimized through the solid waste application as a raw material in other industries. The current study focusses on the utilization of lime sludge with boiler ash synthesized nanosilica for production of belite based clinker at relatively lower temperature. Lime sludge was also used in combination with fly ash and boiler ash to check the synthesis of compounds at varying temperatures. Nanosilica was synthesized from pretreated boiler ash through alkali treatment and acid precipitation. The synthesized nanosilica has been characterized for specific surface area, crystallinity, surface functional groups and size. Three different mixtures, containing lime sludge with nanosilica, fly ash, and boiler ash are fired at temperatures ranging from 900 °C to 1200 °C and characterized for the synthesis of belite. Conventionally, belite is synthesized above 1200 °C, whereas the combined application of lime sludge and nanosilica reduces the temperature of belite synthesis to 900 °C without pre calcination or addition of any chemical stabilizer. In the case of lime sludge and boiler ash blend, belite formation takes place at the higher temperature (1100–1200 °C). Anorthite synthesis takes place in case of lime sludge and fly ash blend, due to high percentage of alumina present in fly ash. Lime sludge and nanosilica based belite clinker are used to develop newer cementitious binder. Hydration and strength properties of developed binder proved worthy as building materials. This study will present alternatives for sustainable utilization of lime sludge, fly ash and boiler ash in construction.

Although paper production demonstrates high energy and water sensitivity in their life cycles, only a few systematic analyses have focused on these issues. Therefore, an energy and carbon coupled water footprint analysis of five types of Kraft wood pulp-based paper (i.e., specialty-, art-, household-, light coated-, and tissue paper) is conducted in this study to help improve the environmental performance of the paper industry. All investigations are conducted with an impact-oriented approach based on ISO standards. Results show that elemental-chlorine-free bleaching is more environmentally friendly than chlorination-alkaline extraction-hypochlorite bleaching, specifically for global warming, aquatic eutrophication, and human health (i.e., carcinogens and non-carcinogens). Gray water footprint along whole life cycles of each product is approximately twice of blue water footprint. Direct processes contribute approximately 50% to water scarcity, while their impact on aquatic eutrophication ranges from 0.002% to 50.72%. For other midpoints, indirect processes dominate the influences. Meanwhile, COD, BOD5, CO2, TP, Cr (Ⅵ), Ti, Hg, and As are key contributors. Finally, reusing sludge by direct burning in the recovery furnace, reclaiming organic compounds in black liquor before alkali recycling, and integrating black liquor gasification technology are expected to provide substantial environmental benefits. Amelioration of wastewater treatment, optimization of the national energy structure, and improvement of the efficiency of chemicals and freshwater are recommended.

This work aims at developing sustainable processes for pulp and paper industry by integration of the biorefinery concept to an existing pulp and paper process. A systematic methodology employing a superstructure-based process synthesis approach is employed with support from computer-aided tools to determine potential pathways for a long-term sustainable growth objective. A superstructure of the multi-product biorefinery process network for the pulp and paper industry is developed. It is divided into three sub-networks, a chemical pulping section, a biochemical production section and a black liquor utilization section. Superstructure optimization is performed with the objective to maximize profit to determine optimal integrated networks for three scenarios. The obtained results provide useful insights for further development of the optimal networks as sustainable integrated biorefinery combined with pulp and paper mills.

To evaluate the effect of brown-rot fungi Oligoporus placenta and earthworm Eisenia fetida on decomposition of paper mill sludge, the paper mill sludge was mixed with cow dung in 0, 25, 50, 75, and 100% proportions and changes in physicochemical quality of waste mixtures was carried out for 28 days. All waste mixtures were treated with: Setup-I (E. fetida), Setup-II (O. placenta) and, Setup-III (E. fetida + O. placenta). A decrease in total organic carbon, C/N ratio and cellulose but an increase in total kjeldhal nitrogen, total phosphorus, total potassium and pH was recorded. The paper mill sludge in 50–75% proportion in feedstock showed the better results and rate of mineralisation were in order: Setup-III > Setup-I > Setup-II. The proportion of CD has direct role in waste mineralisation. The microbial population (bacterial, fungal and actinomycetes) and earthworm biomass were also high in Setup-III, suggesting the influence of brown-rot fungi on paper mill sludge humification. Results indicate that fungal inoculate in vermicomposting was effective in decomposing cellulose-rich industrial sludge.

The non-process-elements (NPE's) in the pulp and paper production, in particular chloride (Cl−) and potassium (K+), eventually accumulate in a sodium sulfate recovery cycle of a paper plant, especially on boiler fly ashes (flue gas cleaning). This accumulation often leads to fouling and corrosion. Thus, in order to reduce such problems, a leaching unit is typically integrated aiming to remove Cl− and K+ and recover sodium sulfate (Na2SO4) from boiler fly ashes. In this context, this research is focused on investigating the effects of temperature, ash concentration and pH on the separation efficiency (Cl− and K+ removal and Na2SO4 recovery) of recovery boiler fly ashes using design of experiments in a devised laboratory setup. As expected from the literature, the results obtained reveals that concentration has the most significant effect on the response variables followed by temperature; whereas pH, not mentioned in this application so far, also has a significant effect. The optimum operating condition, which yields 84 wt% of Na2SO4 recovery and 97 wt% of Cl− and K+ removal, is achieved at 60 °C, 50 wt% of ash and pH 9.0. For practical applications, this optimal condition reduces the accumulation of NPE‘s and mitigates the risks of fouling and corrosion.

Dewatering and handling of pulp and paper mill sludge is challenging and often comprises more than half of the overall wastewater treatment costs at a mill. Primary sludge is usually more dewaterable than biosludge (waste activated sludge), and the ratio between both types of sludge largely determines the dewaterability of the sludge mix. This study has quantified the benefits of adding primary sludge to biosludge to enhance the dewaterability in terms of cake solids and filtrate/pressate solids content. Furthermore, the effects of the particle size distribution and the monovalent to divalent cation ratio of the various types of sludge were investigated. Biosludge and three types of primary sludge from a Canadian pulp and paper mill were mixed at various ratios and tested for dewaterability using a Crown Press®, a bench-scale device which simulates industrial belt press dewatering. Results show that after addition of primary sludge at up to 40% mass proportion (dry solids basis) the dewatered cake solids content increased substantially, from 10.4% to 18.7–19.9%, depending on the type of primary sludge added. Further addition of primary sludge led to comparably only small improvements. Primary sludge addition also resulted in decreased total suspended solids (TSS) concentrations in the combined gravity filtrate / Crown Press pressate. Primary sludge content of only 10% in the sludge mix was sufficient to decrease the TSS concentration from 1.8 g/L to 0.2 – 0.4 g/L. The study shows that only less than half of the sludge mix needs to consist of primary sludge, in order to achieve adequate dewaterability. This opens up the possibility of retaining more primary fiber within the pulping process, without compromising downstream sludge dewatering.

The pulp and paper industry, which provides cellulose pulp and paper, bio-based energy and chemicals, is one of the largest energy consumers, greenhouse gases (GHG) and pollutant emitters among manufacturing industries. Although the environmental impact of the pulp and paper industry has been extensively studied, life cycle assessment (LCA) results have not yet reached a consensus. By means of a systematic review and meta-analysis, this article contributes to the quantification and harmonization of the life cycle environmental impacts of pulp making and paper making systems. Based on the screening of 45 cases of paper making and 18 cases of pulp making, we found that 1 t of paper results in about 950 kg carbon dioxide (CO2) equivalent (CO2-eq) GHG emissions on average. However, there are distinct differences between countries and pulp and paper categories. The dominant factor influencing GHG emissions is energy use. In paper making, the pulp making process is responsible for 62% of energy use, 45% of GHG emissions, 48% of acidification potential, and 49% of eutrophication potential. The kg CO2-eq emissions of three different types of pulp were as follows: Kraft, 508 kg CO2-eq/t; chemi-mechanical, 513 kg CO2-eq/t; and recycled pulp, 408 kg CO2-eq/t. Excluding emissions from electricity and steam production, the convergence of carbon emissions is observed within the same categories of pulp. Straw-based pulp caused far more environmental impact than any other type because of the intensive inputs in agricultural activities as well as in the pulp making process. This research highlighted the inconsistencies in functional units, system boundaries, and methodologies and carbon neutrality assumptions in different LCA studies of pulp and paper making. Future studies should focus on the environmental impact of straw-based pulp making, system boundary unification, and calculation of biogenic carbon emissions.

In order to optimize the biogas recovery from the co-digestion of food waste (FW) and paper waste (PW), the effect of PW content on two-phase anaerobic digestion (TPAD) was investigated. The mixtures of FW and PW, with the ratios of 10:0, 8:2, 6:4 and 5:5 (total solids), were fed into TPAD to recover biomethane. After the long-term expriment, it is elucidated that the methanogenesis in TPAD was stable for PW ≤ 40%. When PW = 50%, NH4HCO3 was added to the methanogenic phase to provide nitrogen. As the indicators of the stability of the anaerobic process, the ammonia and alkalinity in the methanogenic phase were simulated for their decreasing trend. The simulation results quantified the nitrogen deficiency in the methanogenic phase for PW = 50%. Also, the comparison of alkalinity and ammonia revealed that ammonia was the major contributor to the alkalinity. Furthermore, via stoichiometric calculations, high C/N ratios were found to increase the microbial yield and exacerbated the nitrogen deficiency. In the energy estimation, adding PW showed significant increase only when PW ≥ 40%. It was concluded that 40% was the optimal PW content for bioenergy augmentation from co-digestion of FW and PW using TPAD.

In remote areas, such as India, Africa and Southeast Asia, typically not connected to the natural gas distribution network, tissue paper production is currently carried out using a Yankee cylinder and two hot air hoods heated with saturated steam produced in conventional boilers. In this way the drying air is heated at medium temperature, around 160-180 °C, with consequent low levels of dried paper production. In this context, the present study intends to evaluate the technical and economic feasibility of using a wood biomass fixed bed downdraft gasification plant for the production of syngas to be used as fuel in gas hoods, in order to reach high drying temperatures (around 500 °C), comparable with those of the current modern hoods powered with natural gas. Using previously developed calculation codes, an evaluation of energy performance of the paper drying system and of the gasification plant has been performed. The present study also evaluates the possibility of applying a CHP plant, powered by biomass, for the production of steam and electric, this last obtained adopting a steam turbine, thus covering all the electrical and thermal needs of the paper mill. Results show that, for a paper mill with a production of about 80 t/day of paper, two gasification reactors with a thermal output of about 1.95 MWt, and a consumption of dry biomass of 0.86 t/h, are required. For the steam system, the net electric power needed to meet the needs of the paper mill is about 3100 kW with a consumption of 4.72 t/h of moist biomass and a net efficiency of 23.9 %.

The need to view innovation policy through the lens of policy mixes has gained momentum given the growing complexity, the dynamics of real-world policy and the wide array of difficulties to address the current great societal challenges, notably the increasing pressure on the ecosystems that support our society. One of the main challenges concerning the transition towards bioeconomy, is to gain a more in-depth understanding on the policy mix to stimulate innovation in sustainability transitions. Our paper aims at enriching the portfolio of empirical case studies on policy mixes for innovation and sustainable transitions, by investigating the development of the policy mix underpinning the sustainability transition of the pulp and paper industry in Sweden. We apply a case study approach which draws on event history analysis, semi-structured interviews with industry and policy makers, literature reviews, a participative workshop with stakeholders from the pulp and paper industry, as well as on the IEA databases on climate change and energy efficiency policies and measures. Our analysis emphasises coordination, timing and scale in policy mixes as important elements to understand how instruments interact to accelerate sustainability transitions. The mapping of the policy mix shows that destabilising policies were crucial for accelerating the transition process of the industry. Prior to novelty creation policies, destabilising policies (e.g. environmental policies) were needed for 'innovation policy instruments' to be effective. More specific instruments (e.g. carbon tax), targeting particular functions of the innovation systems, require 'on-the-ground' policy intelligence and benefit from close interaction with industry.

The pulp and paper industry, one of Canada’s largest and most important industries, produces many by-products, some of which are used to produce electricity and steam for mill operations; however, the by-products are not used economically. The industry has been facing financial challenges and, therefore, an appropriate means of converting by-products to value-added products is highly desired. In this study, we explore nine pathways for the conversion of black liquor, the major by-product of the industry, to different value-added final products. These include steam, electricity, dimethyl ether, Fischer-Tropsch liquids, mixed alcohols, methanol, acetone, butanol, ethanol, and lignin. The most economical conversion pathway is selected based on the internal rate of return (IRR) calculated through a techno-economic assessment. Lignin production through the fractionation of black liquor is the most attractive scenario. Sensitivity and uncertainty analyses were performed on the IRR for the lignin production scenario to evaluate the effect of different parameters on overall performance and assess the accuracy of the results. The sensitivity analysis shows that lignin price and operating costs are the most influential parameters on IRR. This study offers insights into options of revenue generation for the pulp and paper industry through the innovative use of its by-products.

Organic-rich pulp and paper mill sludge (PPMS) has the potential to become a renewable carbon source for producing alternatives to fossil-based product. In this work, PPMS treated by hydrothermal carbonization (HTC) was investigated based on its pyrolysis properties. The pyrolytic mechanism, kinetics data and product of the sample were studied using TG as well as pyrolysis tests in Py-GC/MS and a bench-scale reactor at 450, 550, and 650 °C. The results show that the thermal decomposition of feedstock is a two-stage reaction. The mean activation energy of the pyrolysis of HTC treated PPMS was estimated as 233.08 kJ/mol, which is higher than that of the pyrolysis of paper sludge reported before. The changes in enthalpies, entropies and Gibbs free energies from the reactants to the activated complex were estimated. The concentration of monocyclic aromatic hydrocarbons in the derived organic liquid fraction shows a positive correlation with the pyrolysis temperature. At 550 °C, the organic liquid fraction reached its highest yield at 13.7% with an oxygen level of 10.7 wt% and a higher heating value of 35.9 MJ/kg. The pyrolytic chars show that a molar ratio of O:C is less than 0.2, which shows potential for use as a carbon sink.

Activating flux is made up of inorganic material mixed with a volatile medium. The objective of this study is to identify and review the literature in activating flux, and different type of welding techniques. For that purpose, a structured review method is adopted and the Scopus database is used as a primary source for the selection of papers. The papers were identified using the string term of “Activating flux” OR “Activated flux” in the title of papers. And a total of 238 papers were identified for the study. Besides the above few other papers were also reviewed and the materials used, the type of flux used, and the findings of different combinations were highlighted in the form of tables. The findings of the study provide a comprehensive understanding of the different type of welding techniques focusing on TIG welding, and the different combination of flux used and their impact was summarized.

Using waste paper as fuel for domestic heating is a beneficial recycling option for small island developing states where there are lacks of resources for energy and waste treatment. However, there are concerns about the impact of air pollutants emitted from the burning of the self-made paper briquettes as household air pollution is recognised as the greatest environmental risk for human. In this study, combustion tests were carried out for paper briquettes made in one Pacific island and three commercial fuels in Australia including wood briquettes, kindling firewood and coal briquettes in order to: 1) characterise the emissions of three criteria air pollutants including particulate matters, CO and NOx including their emission factors (EF) from the tested fuels; and 2) compare the EFs among the tested fuels and with others reported in the literature. The results showed that waste paper briquettes burned quickly and generated high temperature but the heat value is relatively low. Paper briquettes and coal briquettes produced higher CO concentration than the others while paper briquettes generated the highest NOx level. Only PM2.5 concentration emitted from paper briquettes was similar to kindling firewood and lower than wood briquettes. Burning of paper briquettes and wood briquettes produced particulate matter with large average count median diameter (72 and 68 nm) than coal briquette and kindling firewood (45 and 51 nm). The EFs for CO, NOx and PM2.5 of paper briquettes were within the range of EFs reported in this study as well as in the literature. Overall, the results suggested that using paper briquettes as fuel for domestic heating will not likely to generate higher level of three major air pollutants compared to other traditional fuels.

Anaerobic treatment of sedimented fibers collected from bottom of a bay that had been receiving pulp and paper mill wastewater for about 70 years were studied for the first time in semi-continuously fed continuously stirred tank reactors (CSTR). Anaerobic treatment of the fiber sediment was shown to be feasible, without dilution and with nitrogen and buffer supplement, at organic loading rates (OLR) up to 2.5 kg VS/m3d and hydraulic retention times (HRT) of 60 d resulting in methane yields of 201 ± 18 L CH4/kg VS. Co-digestion of sedimented fiber with sewage sludge at an OLR of 1.5 kg VS/m3d and HRT of 20 d resulted in a methane production of 246 ± 10 L CH4/kg VS. The techno-economic feasibility of mono and co-digestion process together with several case dependent factors such as maximum operable OLR, digestate utilization needs to be evaluated before making further conclusions for larger scale remediation applications. acceptedVersion

This study aims at to make a heuristic analysis of energy efficiency performance of Indian paper industry in a non-parametric production theoretic approach. Using the data for 2004–05 to 2013–14, radial and non-radial variants of DEA were employed to estimate energy saving potential and identify the relative position of paper industry across the states. Preliminary analysis in terms of energy intensity scores showed declining trends of energy intensity over the period of analysis for most of the states except states like Assam, Chhattisgarh, Kerala and Punjab where it does not decline much. Assuming a variable returns to scale (VRS) technology under the conditions of inherent heterogeneity and market imperfection, the slack-based measure (SBM) reported a much higher energy saving potential than reported by other measures in the study. Further by taking scale efficiency into account, the study documented the higher contribution of pure energy inefficiency in explaining the total energy inefficiency within the paper industry relative to scale inefficiency. Finally, the study recommends the propagation of energy efficiency program through a market-based and regulatory mechanism along with consolidation and technological advancement of individual units, in order to tap vast energy saving potential and thereby ensure the growth and environmental sustainability.

With the surging energy price and environmental concerns, measures to improve energy efficiency have attracted increasing concerns of the manufacture sector, especially energy-intensive manufacturing industries such as tissue paper mills. Energy-efficiency scheduling, as a novel energy-efficient method, has attracted the attention of an increasing number of researchers in recent years. Drying process is the most energy-intensive production process in tissue paper mills, which has a great energy-saving potential. This paper aims to reduce the energy costs for the tissue paper mill, consisting of processing energy cost and set-up energy cost, through integrating drying process optimization with energy-efficient scheduling. First, the energy cost model and the scheduling model were built. Then, the energy cost of the drying process of every job in a given scheduling problem was optimized using particle swarm optimization (PSO). Afterwards, the energy cost was further optimized using energy-efficiency scheduling. In addition, a hybrid non-dominated sorting genetic algorithm II (NSGA-II) was utilized to solve the energy-efficiency scheduling problem. Finally, several real scheduling problems from a real tissue paper mill were addressed using the proposed approach to demonstrate its effectiveness in energy saving. The experiment result showed that there is a great energy-saving potential in the drying process, accounting for up to 12.53% of the total energy consumption. Moreover, the maximum energy saving ratio of the proposed approach could reach 9.03%. On the whole, the proposed approach can provide a new energy-saving method for tissue paper mills or other manufacturing industries.