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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.

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.

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.

Aeration, as a process in pulp and paper wastewater treatment, uses the greatest share of the energy. Therefore, if the energy efficiency of the treatment has to be improved, the focus must be on aeration. A key finding from the trials conducted for this paper, with effluent from a paper and pulp mill, was that the oxygen transfer coefficient could be doubled and the chemical oxygen demand could be decreased by 25%, if the effluent was pre-treated with 30 mg/l of aluminium coagulant (equivalent to 9.4 tonnes per day of AVR to 20000 cubic metres of effluent). Decrease in oxygen requirement implies decreases in aeration energy use. Pulp and paper mill effluents are not as biodegradable as municipal sewage, and the improvement in oxygen transfer properties of the effluent will have a positive influence over a longer period of time in the biological treatment. If the sludge is digested anaerobically, pre-treatment will also result in doubling the potential for methane generation. A holistic analysis of modifications to processes entails a study of the economic and environmental consequences as well. While the economic aspect is beyond the scope of this paper, only the net global warming as an environmental impact category has been studied, by taking recourse to specific emission coefficients. Of the four dosages of ferric aluminium sulphate considered in this analysis, the net greenhouse gas emissions are the least – 426 kg carbon dioxide equivalent per day when the daily consumption is 9.4 tonnes.

The paper and cellulose manufacturing industry generates significant quantities of waste, including an extremely humid sludge, which is considered to be an effluent with high environmental liability for the manufacturer. Studies have shown that this waste sludge may be utilized in construction material, such as mortar for fixing blocks, as well as for ceiling and wall coatings that use ceramic masonry as a sealant. The recycling of pulp and paper industry waste sludge has important environmental benefits, by preventing soil and water pollution caused by inadequate disposal and by reducing the depletion of natural resources, such as lime, used in cementitious materials. This study analyzed the sustainability of incorporating such waste into cement-based mortars. Tests were conducted replacing lime, one of the most expensive mortar components with high environmental impact, with waste sludge in contents of 5%, 10%, 15%, and 20%. Analysis was then performed on the samples to assess the primary technical characteristics of these incorporated mortars, such as the consistency index, heat of hydration, content of incorporated air, water retention, mechanical strength and the capillarity coefficient. The results were compared with the results of the characterization tests that were performed on the waste material. The results showed that for use in wall and ceiling mortar coatings, the level of incorporation should not exceed 10%, because higher levels yield lower values of mechanical strength resistance, incompatible with market requirements. This result is probably due to the low heat of hydration of the waste material which generates slower reactions. On the other hand, higher levels of waste material content, above 10%, are appropriate convenient for mortar used to fill small repairs in masonry that do not require control of properties.

The increasing presence of e-books (electronic books) has become a major focus in countries around the world. In the United States, e-books represented 28% of the total book sales for 2012. In Japan, the conversion from paper books to e-books is expected to accelerate by the prevalent use of smartphones and tablet PCs. It is therefore important to quantitatively evaluate the environmental load of paper books and e-books for a sustainable society. In this study, paper books are compared to e-books read on different electronic devices (e-ink tablets, tablets, cell phones, smartphones, laptop computers, desktop computers and portable music players) through a case study on a 224-page book. The study is based on key primary data such as use time and reading speed for each device and aims to minimize assumptions made in other studies. GHG emissions for paper books are 1.24 kg-CO2e/book, and are reduced to 1.11 kg-CO2e/book when the effect of paper recycling is taken into consideration. The results for e-books under average use-time conditions range from 0.25 to 0.91 kg-CO2e/book with the e-ink tablet having the lowest emissions. When the average use time of each e-book device is applied, the paper book has a higher impact than all the e-books. However, sensitivity analysis shows that the impact of paper books can be lower than that of e-books for larger screen devices such as tablets, laptops and desktops when the reuse of books is considered or the e-book reading device is hardly used during its life cycle.

Guiding industries to produce in an effective and environmentally sustainable manner has become a key issue for governments around the world. Over the past 15 years, series of regional and industrial development policies have been introduced by the Chinese government. This has influenced the geographical distribution and energy efficiency performance of China’s industries. This paper quantifies the influence of enterprises geographical distribution on energy efficiency improvement in the paper industry and aims at providing some helpful suggestions on industrial development to policy makers. The main results show that, firstly, the paper industry in eastern China shows obvious characteristic of agglomeration. The average location quotient is 1.2278. However, following the industrial and regional development policies, the characteristic of agglomeration is weakening. Secondly, only when agglomeration reaches a certain level (location quotient is above 0.5447) will industrial agglomeration positively impact on industrial energy efficiency improvement (a 1% increase in agglomeration will increase dynamic energy efficiency by at least 0.23%). Thirdly, the regional development policies carried out by the government slow the pace of energy efficiency improvement in China’s paper industry. The empirical results indicate that the government needs to consider regional characteristics and consciously guide industrial enterprises to concentrate in the dominant area.

Different heating processes were applied to pretreat the pulp and paper mill sludge to enhance the hydrolysis stage. Hot air oven, autoclave, microwave and water bath were used for comparison. Chemical analyses exposed that all the pretreatment methods have shown improvement in solubilisation of organic matter. Among the pretreatments studied, heat transfer through hot air (80 °C for 90 min) mode had the highest impact on sludge solubilisation. There was an increase in cellulose (P = 0.0096), acid soluble (P = 0.0053) and insoluble lignin (P = 0.0012), but decrease in hemicellulose (P = 0.0009) content after pretreatment. The XRD and FT-IR spectroscopic characterisation shows the development of aliphatic, unsaturated and carbonyl carbon functionalities in the pretreated samples at higher severities. FESEM picture also confirms the change in structure after pretreatment. Thus, pretreatments contribute to disruption of the lignocellulosic structure making the cellulose easily accessible to acidogenic microorganisms.

In this study, a mathematical model has been developed for sustainable inventory, in which the effects of environmental factors on social factors, have been investigated. To this end, first, we revised Economic Order Quantity (EOQ) model by adding income from waste sales to this model. Next, considering the emission of sulfur oxides (SOx), nitrogen oxides (NOx) gases, Biochemical Oxygen Demand (BOD) and chemical oxygen demand (COD) indicators in waste water as a measure of water organic pollutants, we proposed a Green Economic Order Quantity (GEOQ) model. Then in order to examine interdependency between environmental aspects and social aspects, we introduced the sustainable model by adding environmental ergonomics in the terms of the effect of SO2 emission on human health. Since the structure of the model consists of nonlinear objective function and linear constraints, the model could be solved based on an exact nonlinear constrained solution method. Finally, we examined the effectiveness of the proposed model demonstrated in a real case study of pulp and paper mill. Validation of the model was done by comparing the cost function of the proposed model with the pure economic model and the actual data. The results of study showed that proposed sustainable model plays a significant role in determining the order quantity and reduction of cost function, sulfur oxides (SOx) and nitrogen oxides (NOx) emissions, and Biochemical Oxygen Demand (BOD) and chemical oxygen demand (COD) in waste water.

Reducing waste materials through reuse has in the recent past contributed to sustainable manufacturing in many industries. With the development of large-scale poultry farming, the treatment of large amounts of chicken feathers has become a problem and threatened its use as a renewable resource. This paper examines the use of chicken feathers in the paper making process; a process which would traditionally use wood as the raw material. The effects of combining feather fibre and wood pulp on paper performance were studied and compared to the properties of handsheets made with 100% wood pulp. With the increase of feather content, properties such as tightness, tensile index and bursting index decreased, whilst air permeability improved. There was no significant difference in water absorbency between various chicken feather/wood pulp handsheet samples however, the water absorbency started to decrease above 80% of chicken feather content. This could potentially open up a new avenue for the use of chicken feathers in applications that are meant to tolerate high humidity conditions, e.g., packaging products.

Utilization of the quality-upgraded waste paper in the manufacture of paper and board will reduce the wood consumption and pulping energy. While the optical property of the fibers from recycled old newspaper is very poor, in-situ calcium carbonate formation on those fibers by injecting carbon dioxide to the mixed slurry of those pulp and calcium oxide improved their brightness. Upgrading recycled old newspaper to substitute more expensive wood furnish, such as recycled old magazine, was successfully demonstrated in the present study. This study showed that the in-situ calcium carbonate formation process improved the optical quality of the recycled old newspaper by covering colored impurities with newly formed calcium carbonate, and improved calcium carbonate retention in papermaking process by attaching them to fibers. The strength reduction by the presence of newly formed calcium carbonate in the paper was recovered by adding strength agent. High ash retention at high ash content under the strong turbulence in the modern paper mill was achieved by the application of the in-situ calcium carbonate formation method. The quality-upgrade of recycled fibers and cost saving in the manufacture of duplex paperboard were demonstrated in the mill trial.

In recent years, the pulp and paper industry has changed a lot and products have been constructed in quite different methods using new technologies. It can be due to the emergence of challenges and constraints such as shortage of raw materials, energy consumption (fossil fuels, electric, etc.), management of the resulting pollutants, environmental issues, ongoing legal requirements and cleaner production strategies. In Iran, the pulp and paper industry's technological development is not keeping pace with global growth. Iran's pulp and paper mills supply a small fraction of domestic market. The reasons can be due to old technologies being used in factories, aging machinery, low productivity of production systems and lack of coordination with modern technologies. It leads to low-quality of paper products and willingness to buy local products. The aim of this study is to select the most appropriate technologies in the pulp section, due to high impact of pulp quality on the quality of final paper. Using a 2-filterd fuzzy decision-making, hierarchical structure of research is designed to assess technological alternatives according to the selected criteria. Findings show that after passing through two filters, Kraft method was chosen as the most appropriate method. The Kraft process has still many advantages like the high quality of the produced pulp and self-sufficiency in energy supply. This framework offers an appropriate procedure for identifying and selecting technologies that has not been used in past researches. Using this framework facilitates using a clear procedure for evaluating and selecting technology and prevents future losses for organizations.

International audience; An energy audit is a primary step toward improving energy efficiency at the facility level and ensuring a clean production. The pulp and paper sector is one of the most energy-intensive industries in Morocco. This article aimed at identifying energy conservation opportunities at a Small and Medium-sized paper industry. The audit results together with their financial viability are presented regarding the analysis of energy consumption and electrical quality issues. The paper introduces an action plan for a more efficient energy use of some specific applications such as furnaces and compressed-air installations as well. The recommended energy efficiency measures have the potential of saving about 347.85 MWh of electrical energy and 101.78 MWh of thermal energy corresponding to reductions of 11.48% and 2.22%, respectively. The total investments related to the application of the action plan is approximately 290.53 kMAD and the global payback period does not exceed one year. It was also shown that a total quantity of 283.39 t of CO2 emissions can be saved annually.

Pulp and paper is considered to be the fourth most energy-intensive industry (EII) worldwide. However, as most of the CO2 emissions are of biomass origin, this sector has the potential to become a carbon-negative industry. This study proposes a new concept for conversion of the pulp and paper industry to carbon negative that relies on the inherent CO2 capture capability of the Kraft process. The techno-economic performance of the proposed carbon-negative system, based on calcium looping (CaL) retrofitted to a pulp and paper plant, was evaluated. The effect of CaL design specifications and cost assumptions on the thermodynamic and economic performance were evaluated. Under the initial design assumptions, the reference pulp and paper plant was shown to turn from electricity importer to electricity exporter with the cost of CO2 avoided equal to 39.0 €/tCO2. The parametric study showed that an increase in the fresh limestone make-up rate resulted in a linear increase of the specific primary energy consumption for CO2 avoided (SPECCA) and a reduction in the amount of electricity exported to the electric grid. This translates into an increase in the price of pulp and newsprint, and the cost of CO2 avoided. This study has also demonstrated that the pulp and paper industry has high potential to become carbon negative. It has been shown that carbon capture and storage would become economically viable in this industry if the negative CO2 emissions are recognised and a negative CO2 emissions credit of at least 41.8 €/tCO2 is implemented.

Fly ash and waste lime are solid wastes generated in pulp and paper mills. Due to high CaO contents, these secondary lime materials can be potentially utilized in the steelmaking process to partially replace primary lime. In this study, fly ash and waste lime from Swedish pulp and paper mills were made into briquettes and for the first time utilized as slag formers to replace primary lime in a pilot-scale Argon Oxygen Decarburization (AOD) stainless steelmaking process. The purpose was to evaluate how these CaO-containing materials could affect the AOD process and the steel quality. The results show that the S, P and CaO contents in the fly ash and waste lime are important concerns for metallurgical application. Firstly, due to lower CaO contents (61.5% CaO in fly ash and 90.6% CaO in waste lime versus 95.2% CaO in primary lime), utilization of these secondary lime materials could lead to higher slag amounts in the AOD converter. Secondly, due to higher S and P contents (0.40% S and 0.26% P2O5 in fly ash, 0.11% S and 0.75% P2O5 in waste lime versus 0.08% S and 0.01% P2O5 in primary lime), utilization of these secondary lime materials could increase the S and P contents in the steel. The S content in the steel can be controlled during the reduction and desulfurization stages; however, the P content in the steel increases with an increased use of these secondary lime materials. Thirdly, the metallurgical performance of fly ash and waste lime is as good as primary lime when considering the aspects that: (a) utilization of fly ash and waste lime doesn’t have negative effects on the decarburization stage nor on the reduction stage during the AOD process; and (b) fly ash and waste lime are as efficient desulfurization agents as primary lime. In future industrial applications, the alkali content and the variations of chemical compositions (especially with respect to S, P and CaO) of these secondary lime materials need to be carefully controlled to ensure a sound metallurgical operation.

The pulp and paper industry accounts for approximately 5% of total industrial energy consumption and contributes 2% of direct carbon dioxide (CO2) emissions from industries. World paper and paperboard demand and production are increasing significantly, leading to an increase in this sector's energy use and CO2 emissions. Although current studies identify a wide range of energy-efficiency technologies that have already been commercialized for the pulp and paper industry, information is limited or scattered regarding new energy-efficiency technologies that are not yet fully commercialized. Development of emerging or advanced energy-efficiency technologies and their deployment in the market will be crucial for this industry's mid- and long-term energy saving and climate change mitigation strategies. This paper compiles available information on energy savings, environmental and other benefits, costs, and commercialization status for 25 emerging technologies to reduce the energy use and CO2 emissions. The purpose is to provide a well-structured comprehensive review on these emerging energy-efficiency technologies for engineers, researchers, investors, policy makers, pulp and/or paper companies, and other interested parties.

The objective of this work was to examine opportunities for reducing the overall cost of lignocellulose hydrolysis to fermentable sugars. Primary sludge (PS), a negative cost lignocellulosic feedstock, was hydrolyzed sludge using a commercial cellulase preparation (Cellic® CTec2) in presence of non-ionic surfactants. Polyethylene glycol (PEG) 4000 facilitated the highest hydrolysis yield of 74.4% which represented a 2-fold increase over the control without surfactant. Response surface methodological analysis at four variables (hydrolysis time, solids, enzyme, and surfactant loadings) revealed that enzymatic hydrolysis was significantly enhanced by the interactive effect of all factors with solids and enzyme loadings as the most significant parameters (p

Green liquor dregs and slaker grits are pulp and paper mill residues usually landfilled. Whit high calcium carbonate content, its use as alternative raw materials in traditional ceramic products becomes an interesting study field. In order to evaluate its incorporation potential, the residues characterization with diverse approaches was performed and for the first time reunited exploring this eco-friendly intent. Green liquor dregs and slaker grits were characterized by its chemical and mineralogical composition (XRF, XRD, FT-IR); physical and morphological characteristics (particle size, BET surface area, density, SEM) and thermal properties (TGA). Chemical and mineralogical analysis reveals the high calcium carbonate content in calcite form especially on slaker grits, that has less inorganic and organic contaminants than green liquor dregs. Smaller irregular-shaped particles and bigger surface area was found on this last residue, comparing with slaker grits. The thermal analysis indicated a lower calcite decomposition for green liquor dregs (720 °C), while this event on slaker grits occurred 40 °C above (760 °C). Thus, it was observed the residues behavior and characteristics are much alike calcium carbonate itself, especially slaker grits, considering its composition, morphology and thermal events. As conclusion, the potentiality uses of green liquor dregs and slaker grits as alternative raw materials on ceramic products was revealed. Being able to incorporate clay, concrete, glasses and great majority of other ceramic products, these residues use will generate excellent benefit-cost ratio to industries and environment.

LCA studies on waste management have been promoted as they can help policy makers choose the best environmental options. However, the increasing globalization of raw materials and waste makes the optimization of waste management strategies and policies quite challenging. Therefore, new approaches are needed in order to identify the consequences of markets on the waste management systems. This paper concentrates on the quantification of greenhouse gas (GHG) emissions of recycling processes. The aim is to generate a comprehensive assessment of GHG emissions as a consequence of increasing the amount of material collected for recycling. Consequential life cycle assessment (CLCA) is an effective methodological framework for addressing GHG quantifications within market, but to properly perform and assess all of the market links between raw materials and waste, it is necessary to determine the cause-effect chains made up of physical flows. Thus, we propose integrating the methodologies of material flow analysis (MFA) and CLCA. We applied these methodologies to the paper and cardboard recycling system in Spain. The GHG results varied between −36 kg CO2 eq. and −317 kg CO2 eq. per ton of waste paper collected, depending on the quantity of waste paper exported and the source of marginal pulp considered. The cumulative energy demand (CED) was also calculated as complementary indicator. Similar trends as for GHG emissions were obtained. The future GHG quantifications should be based on the flows described by MFA analysis and should be quantified using CLCA because methodologies that accurately account for GHG are necessary for decision-making.

Chemical pulp is one of the most important raw materials used in the paper industry. This material is known to make a significant contribution to the water footprint and cost of final paper products; therefore, chemical pulp is crucial in determining the competitiveness of final products'. Several studies have focused on these aspects, but there have been no previous reports on the integrated application of raw material water footprint accounting and costs in the definition of the optimal supply mix of chemical pulps from different countries. The current models that have been applied specifically to the paper industry are based mainly on general sectorial data; therefore, they cannot reflect the importance of the efficiency of the different processes in the supply chain of paper production. The objective of this study was to develop a multi-objective optimization model to identify the supply mix that minimizes the water footprint accounting results and costs of chemical pulp, thereby facilitating the assessment of the water footprint by accounting for different chemical pulps purchased from various suppliers, with a focus on the efficiency of the production process. Water footprint accounting was adapted to better represent the efficiency of pulp and paper production. A multi-objective model for supply mix optimization was also developed using multi-criteria decision analysis (MCDA). Water footprint accounting confirmed the importance of the production efficiency of chemical pulp, which affected the final results, with an average factor of 4.7 m 3 wood/t paper. The MCDA that we developed was used to determine the optimal mix of chemical pulps from different countries, which demonstrated how the optimal mix changed when considering only one of the two variables. Herein, we also discuss the latest developments in impact assessments related to water based on a life cycle assessment, which should be used as a framework for the future development of the model that is presented.

Straw pulp in China, which is the world's largest producer of this material, suffers from water and energy shortages during its entire life cycle. However, limited systematic studies have focused on these issues, and decision makers need be provided with improvement methods for the environmental performance. Thus, an impact-oriented energy and carbon coupled water footprint analysis was conducted in this study based on ISO standards. Results showed that the impact of energy consumption and carbon emissions exceeded that of water footprint. Carcinogens, non-carcinogens, and freshwater ecotoxicity also played effective roles in improving the environmental performance. Optimizing key indirect processes, including chemicals production, steam preparation, electricity generation, wood pulping, and fertilizer recovery, dominated the reduction in environmental burdens. Direct freshwater consumption and wastewater disposal played additional effective roles in controlling water footprint. The water network was thus optimized by a water pinch analysis to decrease the freshwater consumption and pollutant emissions by maximum values of 91.5% and 99.7% after optimization, respectively. Meanwhile, carbon dioxide, methane, chromium, arsenic, mercury, titanium, copper, strontium, total nitrogen, total phosphorus, BOD5, and COD were the main pollutants. Overall, the environmental impact can be further reduced by diminishing coal power ratio in national energy structure, adopting recovered steam, and considering multistage regeneration water network to cope with different water use demands.

The purpose of this study was to assess the environmental impacts of the Norwegian pulp and paper industry, considering the production of pulp fibres and printing paper. The pulp fibres included in this study are thermo-mechanical pulp and kraft pulp fibres, which differ with respect to the energy consumption and chemicals used during production. The assessed paper grades were super-calendered paper and newsprint. The study was a cradle to gate approach, and corresponds to an attributional life cycle assessment (LCA). The LCA was based on data collected from main pulp and paper producers in Norway. Importantly, aspects related to the increasing use of mineral fillers in the production of newsprints were assessed. The results showed that a reduction of more than 18% climate change impact (kg CO2 eq.) was achieved by increasing the fraction of fillers, in the newsprint furnish. Furthermore, the total climate change impact reduction depended on the applied energy mix. Assuming that the production of printing paper was based only on Norwegian energy mix, yielded a reduction of the climate change impact by more than 44% in 2011, compared to the production based on Scandinavian and European energy mix. Additionally, the input and output transport contributed to more than 20% impact in several cases. We thus concluded that the estimated environmental impacts were affected by; i) the furnish composition of a given paper quality, ii) the input and output transport and iii) the use of different primary grid energy sources.

The global cement industry produces over four billion tonnes annually. In recent years, the quest for increasing energy efficiency has led this industry to test and use “waste” materials as alternative fuels (AF). The objective of this study was to examine the use, as alternative fuel, of the shredded non-recycled plastics and paper residue (NRPP) of a materials recovery facility at the Balcones plant in San Antonio, Texas; this material has a Lower Heating Value (LHV) of about 17 MJ/kg and is called “engineered fuel” (EF). The results showed that EF consists of mostly paper fiber, a biogenic material, so its use helps to decrease CO2 emissions from cement production. In the US, on an average about 4.3 MJ of thermal energy are used to dry, decompose, and sinter the carbonate minerals to produce one kg of “clinker” that is then ground to cement powder and mixed with other compounds. If the maximum amount of EF that can be used by the U.S. cement industry (83 million tonnes of cement per year) were to be separated at Material Recovery Facilities and used as alternative fuel in cement kilns, the diversion of non-recycled paper and plastics from landfills would amount to 17.7 million tonnes of EF. The general methodology used for the Life Cycle Assessment (LCA) is Eco-indicators 99 that uses the SimaPro database and four scenarios were assessed. The corresponding chemical structure of the EF was calculated and the associated emissions during combustion were determined. The laboratory analyses determined the average makeup of the sampled fuels consisted of 20% fossil based carbon and 80% biogenic. The use of EF in the cement industry reduces greenhouse gas emission by up to 3 tonnes of CO2 per tonne of EF used in place of a high-quality coal. The study also found that use of EF in cement production has no adverse effect on the stack emissions of cement plants, nor on the quality of cement produced. The mercury concentration in the stack gas of U.S. cement kilns is well below the U.S. standard and the total dioxin emissions of all cement plants amount to only 0.05% of the dioxins emitted by all U.S. sources. Furthermore, the cement process incorporates the residual ash in the EF into the final clinker, thus resulting in both energy and materials recovery.

Currently there are several methodologies available for estimating the carbon footprint of products. In this study a comparison has been made between the outcomes and the implications of three different methodologies applied to office paper: (1) the ISO 14040/14044 standards limited to the analysis of greenhouse gas (GHG) emissions and the corresponding impact category global warming; (2) the PAS 2050; and (3) the Confederation of European Paper Industries (CEPI) framework. The carbon footprint of office paper from cradle-to-costumer is 4.64, 4.74 and 4.29 g CO 2 eq per A4 sheet according to, respectively, the ISO 14040/14044 standards, the PAS 2050 and the CEPI framework. The ISO 14040/14044 standard methodology allows the quantification of 98% of the total GHG emissions with the smallest effort in data collection. The major hot spots are the stages of eucalypt pulp and office paper production and chemical and fuel production for all methodologies. General methodologies such as those analysed in this study are not enough for the comparison of products. More specific rules, such as Product Category Rules, that limit the degree of freedom in the choice of the functional unit, system boundary, allocation rules, data quality, between others, should be developed.

Growing demand for paper is putting pressure on the World's forests, and although paper made from agricultural residues could meet global demand five times over, today less than 10% is made using these resources. The primary reason for this is the absence of cost effective, small-scale (∼10,000 tonnes per annum), environmentally sound pulping technology. The BioRegional MiniMill was developed in response to this problem. The MiniMill is a modular, regional scale, sustainable pulping process designed for straw and other non-wood feedstocks. The MiniMill innovates in two key areas: (i) preparation, feeding and pulping of straw using a twin screw extruder to reduce energy use, produce pulp in a shorter time and improve pulp quality, and (ii) the inclusion of a small-scale black liquor chemical and energy recovery system, based upon novel fluidised bed technology. The MiniMill is projected to be cost competitive at less than one-tenth the size of the smallest conventional wood-based pulping mill. As with conventional pulp mills, the MiniMill recovers enough renewable energy from the effluent to power the mill and qualifies for carbon emissions credits in accredited countries. In this work we report on some of the key research and development activities, at laboratory, pilot and semi-industrial scale, that have underpinned the design and development of the MiniMill. The ultimate goal of the project is to make available a technically and economically viable process for small-scale cellulose pulp production, that will facilitate the uptake of alternative uses of wheat straw, hemp or flax into the market place.

This article evaluates the impacts of integrated environmental permits on the environmental performance of Finnish pulp and paper industry. It assesses the performance of the Finnish pulp and paper mills in relation to the EU best available techniques (BAT) associated emission levels and compares the emission limit values and product specific emissions of the mills with non-integrated permits to those of the mills with new integrated permits. A set of practical indicators for the assessment of BAT, local conditions and transboundary effects is presented and discussed. Moreover, the paper highlights some significant cross-media aspects in the Finnish pulp and paper industry.

Environmental problems caused by recycling wasted paper at a board paper mill provide the material of this study. Two scenarios have been investigated: The first being the treatment of the end-of-pipe, and the second being the control and management of pollution problems through the application of in-plant control and pollution prevention measures. Comparison between the two alternatives, based on a cost-benefit analysis and compliance with National Environmental Laws was done. From this study it was apparent that the implementation of the pollution prevention measures such as the recovery of fiber, reduction of fresh water consumption, and optimization of white water usage proved to be very cost effective. All the implemented solutions have short payback periods and resulted in great savings compared with the treatment of the end-of-pipe.

The papermaking industry has developed rapidly in recent years in China. Papermaking is a high-energy-consuming process. Consequently, large-scale paper mills usually have cogeneration systems that supply both electricity and steam for the papermaking process. In China, almost all these cogeneration systems in paper mills are powered by coal combustion, which consumes a large amount of energy and emits large amounts of greenhouse gas. The Integrated Gasification Combined Cycle (IGCC) technology is regarded as a clean and efficient method of coal utilization. In this work, an IGCC process for application in paper mills was designed and modeled. An IGCC coupled with a cascade refrigeration process (CRP) was further proposed in order to reuse the waste heat from the dryer section and improve the energy efficiency of the papermaking process. A paper with a conventional cogeneration system, one with an IGCC cogeneration system, and one with an IGCC coupled with a CRP cogeneration system were analyzed and compared in terms of energy efficiency, capital investment, operational cost, and dynamic payback period. The results showed that the integration of IGCC technology allows paper mills to be more competitive than those featuring conventional cogeneration systems in terms of energy efficiency and operational cost.

Although there is a pragmatic side of nanotechnology, active and applicable today, its possible applications in the paper industry, especially in emissions reduction and dematerialisation, have attracted only limited consideration. Nanotechnology plays a major role in the development of new products to substitute existing production equipment, materials and chemicals with improved performance resulting in potential environmental and cost savings. Reduced consumption of materials also benefits the environment. Moreover, nanotechnology gives possibilities to organise and develop production processes in a more sustainable way—eventually as close to the zero-emissions approach as possible. This study looks at the current role of nanotechnology in the paper industry and its possible future implications with an analysis of both challenges and opportunities with respect to environmentally sound papermaking and consumer concerns such as health effects.

Retrofit process design can be seen as a multi-criteria decision-making (MCDM) problem aiming at selecting the best alternative for improving the performance of a chemical process. There is a growing consensus that environmental considerations, including the environmental impact associated with all life cycle stages of materials, should be integrated in chemical process design. Life cycle assessment (LCA) is a technique that allows quantification of those impacts. However, implementing this technique would increase the decision-making complexity and thus would necessitate systematic tools and methods. The analogy between LCA and MCDM has been recognized, but the systematic evaluation of LCA methodological choices and interpretation in this context is rarely discussed. The importance of those is demonstrated in this paper using a case study involving the implementation of de-inked pulp capacity and cogeneration and an integrated newsprint mill.

In this paper, the Life Cycle Assessment (LCA) methodology is applied to Portuguese printing and writing paper in order to compare the environmental impact of the use of two kinds of fuels (heavy fuel oil and natural gas) in the pulp and paper production processes. The results of inventory analysis and impact assessment show that the pulp and paper production processes play an important role in almost all of the analysed parameters, which do not always result in an important contribution to the corresponding impact categories. The substitution of heavy fuel oil by natural gas in the pulp and paper production processes seems to be environmentally positive.

A process simulation of a high grade coated paper mill has been developed as part of a process integration study. Data necessary to calibrate and validate the simulation developed with the Cadsim Plus® software were obtained by: measurements, samples analysis and estimations through partial and local mass balances. The simulation was designed in a way that allows grade changes to reproduce the mill operation. The simulation is used to support process studies to optimise water and raw materials consumption and to evaluate results obtained by mathematical optimisation. Different scenarios were studied in order to evaluate the feasibility and the effects of process redesign of the mill's networks.

Production of sludge as waste in pulp and paper plants can be considered as one of the serious environmental problems that have to be solved. While landfilling is not a suitable solution from the environmental point of view, thermal treatment proved to be the most appropriate one. This paper describes an efficient way of processing sludge including waste-to-energy aspects. A thermal treatment unit with a capacity of more than 100 tons of wet sludge per day had been built in a large pulp and paper plant some years ago. This pulp and paper plant is located in a mining area. When built, this unit was quite modern. However, because of more and more sweeping environmental laws affecting the process industry, the unit needed a complete retrofit. The retrofit has been realised in three stages. A brief description of the unit for the thermal treatment of sludge is as follows: the waste sludge (after transport from a sludge storage system) is burnt in a multiple hearth incinerator with a fluidised-bed chamber. Then, the flue gas enters a secondary combustion chamber (afterburner chamber). During the first stage of retrofit, only a part of heat from flue gas was utilised for heat recovery (pre-heating air for combustion and fluidisation) and a contact cooler was involved in the unit. The second stage of retrofit can be characterised as a “waste-to-energy” one. The contact cooler was replaced by a system for preheating water for steam generation. Off-gas cleaning system consists of a filter for particulate removal and a three-stage scrubber system. (Several alternatives of retrofit were considered and simulated and the most promising one was selected.)

Developing monitoring system for paper industrial wastewater treatment system is an important route for wastewater reuse and recycling from wastewater, which are regarded as effective way for cleaner production. A novel hybrid deep leaning CLSTMA model, which based on sequential fusion convolutional neural network (CNN), long short term memory (LSTM) and attention mechanism (AM), was developed to monitor the water quality in a full-scale paper industrial wastewater treatment system for energy conservation and emissions reduction. The hybrid CLSTMA model for predicting water quality of paper industrial wastewater treatment system was divided into three steps: spatial information fusion by using CNN module, temporal information fusion by using LSTM module and variable weighted calculation by using AM module. Compare with other models (CNN, LSTM and CLSTM models), RMSE of CLSTMA model for the effluent chemical oxygen demand (CODeff) reduced by 23.3–31.55%, MAE of CLSTMA model reduced by 38.89–74.50%, R of CLSTMA model increased by 8.29–11.86%. For the effluent suspended solids (SSeff), compared with CNN and LSTM models, RMSE of CLSTMA model reduced by 10.26% and 9.92%, MAE of CLSTMA model reduced by 5.37% and 3.44%, R of CLSTMA model increased by 15.13% and 37.21%, respectively. While, R of CLSTMA was consistent with CLSTM model, but RMSE and MAE of CLSTMA model reduced by 16.07% and 7.49% than the CLSTM model. Simulation results demonstrate that the proposed CLSTMA model has a great potential in monitoring paper industrial wastewater treatment system for cleaner production.

The main objective of this project was to evaluate the possibility of reducing the quantity of fibre wasted at one of many hydrocyclone (centrifugal) cleaning processes in a paper mill. It was found that the application of elutriation water to both the tertiary and quaternary cleaners was essential to minimise the fibre discharged to the sewer, and the pressure of this elutriation water had a dramatic effect of reducing the fibre wastage. Accordingly, it has been shown that 150–160 kPa as the optimum pressure range to apply elutriation water to minimise the product grade fibre wasted whilst sending undesired shive fibre to the sewer. Also, monitoring of the press uhle box wastewater revealed that the paper mill has the potential to make substantial cost savings by reducing the waste stream. Further investigation is necessary to determine the types of fibre that are being wasted, and the viability of a screen to recycle the wasted fibre to the process. However, these fibres may be unsuitable to reuse in the process and alternative uses must be found.

Purpose The aim of this work is to quantify the greenhouse gas (GHG) emissions savings potential in magazine paper production through the application of the innovative manufacturing strategies using advanced sheet structure design and fibre modifications. Methods The study applies Life Cycle Assessment (LCA) methodology to two different magazine paper products: supercalendered (SC) paper and light-weight coated (LWC) paper. A cradle-to-gate approach is used aiming to assess the environmental benefits gained through the implementation of new manufacturing strategies in both products. The functional unit of the system was defined as the production of one square meter of finished paper for printing magazines. Conventional and new production processes have been compared. Results and discussion The strategies applied to SC paper resulted in reduction of GHG emissions by 22.9%, with a total of 10.7 gCO2eq emissions saved per square meter of SC paper. In the case of LWC paper, GHG emissions are reduced by 20.3%, which are equal to a total of 19.7 gCO2eq saved per square meter of LWC paper. The influence of certain methodological approaches -functional unit, electricity mix and avoided impacts- in the final results is also discussed in the paper. Conclusions The manufacturing strategies implemented show a remarkable potential for reducing GHG emissions. Taking into account that the pulp and paper industry is a very energy-intensive sector and one of the main GHG emitters, the potential of the strategies for the improvement of the environmental performance of the papermaking processes is significant.

Recycling and recovery of materials from used products is one of the major avenues to reduce material throughput. Ideally, all materials are anticipated for being reused by the economy an infinite number of times. In reality, recovery of secondary materials may be difficult because of high costs, or because of degraded quality compared with virgin materials. The search for potential reduction of throughput in material cycles should be based on a knowledge of the limits to repeated cycles. To gain understanding of recycling limits, we developed a method to estimate the actual reduction potential for each throughput in a material's multi-cycle life. First, we investigated the material flow system of paper in Taiwan, and developed a supply chain network of paper flows. Systematic elaboration of the flows revealed where paper can be recycled and where paper can be lost. Second, we estimated the reduction potential with a material input–output Markov chain model, which maps the distribution and loss of materials on the supply chain processes. The model estimated the quantities and the life pathways of recycled materials across continuous life-cycles. An indicator was used to quantify the total performance of the material across repeated life-cycles. This method offers an opportunity to examine practices that approach the limit of reduction. This case study shows that the use and separation of paper waste after discarding may need to be reformed to extend the life-cycles of the material.

Recycling wastewater of the pulping and paper-making industry are widely considered for clean production, which heavily rely on the timely and accurate monitoring in paper-making wastewater treatment processes. A novel predicting model based on genetic-deep belief network algorithm was proposed to improve the predictive accuracy and reliability for process monitoring. Considering the deep belief networks (DBN) as a deep learning model is aiming to describe the relationship among variables in a complex process modeling, genetic algorithm (GA) was employed to reduce the input variables dimensionality, simplify the network structure and overcome the dynamic characteristic difficulties of process data in monitoring. Compared with DBN and back propagation neural network (BPNN), the GA-DBN effectively achieved a better predictive accuracy than other tests models in complex wastewater treatment processes. The value of the coefficient of determination of GA-DBN model is increased by 1.71–1.86% and 5.21–9.32%, respectively. The GA-DBN model can be structured with fewer variables or samples to describe the complex paper-making wastewater treatment process, obtaining the better model performance and predictive accuracy.

Due to production technologies such as blasting, transportation, and loading, large quantities of dust are produced in surface mines. This dust not only pollutes the environment but also restricts the development of coal mining enterprises. This work aims to use waste paper as raw material for the efficient extraction of cellulose, in which waste materials can be converted to useable materials. This work can broaden the sources of raw materials and provide new methods for the efficient preparation of dust suppressants. As a matrix, sodium carboxymethyl cellulose is a novel crust-dust suppressant that is synthesized by graft copolymerization with polyvinylalcohol and N-vinylpyrrolidone in this study. The results of experiments revealed the high purity of sodium carboxymethylcellulose prepared in flotation for 20 min, the degree of substitution DS > 0.8, and the viscosity of 2% aqueous solution>300 mPa s, which can satisfy the requirements of the experiments. The microscopic reaction and structure of the product are analyzed by infrared spectrometry, scanning electron microscopy and thermogravimetry, and the microscopic mechanism of a crust-dust suppressant is investigated. The reaction process and structural characteristics of the product were analyzed by infrared spectroscopy and scanning electron microscopy, and the product reaction process and final structure were deduced. Thermogravimetric experiments showed that the product had strong thermal stability and ensured the performance of the product during use. This paper reveals the combination of dust suppressants and coal via molecular dynamics simulation. The product performance experiments show that the product has a high shell strength of 98 HA, satisfactory freeze-thaw resistance and high temperature resistance, permeability higher than 15 mm/min, and dust suppression rate of approximately 88% when the wind speed reaches 15 m*s−1 and it can degrade without pollution. In general, the product can effectively suppress coal dust and other forms of dust.

Generation of fines and ultra-fines is a concept that mining and metallurgical sectors can never shy away since the beginning of coal exploration. These coal fines and ultra-fines are what coal mines regarded as waste material without economic value until the present moment. Poor technologies in the past led to stockpiling of large quantities of fines and ultra-fines. Increase in mechanization in the coal mining industry has also led to the generation of large quantities of coal fines and ultra-fines. Several techniques in the mineral processing sector have been explored to beneficiate the coal fines and ultra-fines. The explored beneficiating technologies include enhanced gravity separation, oil agglomeration, flotation, flocculation, spirals, water only cyclone and dense medium cyclone. These beneficiating technologies have their own limitations when treating fine and ultrafine coal. Major limitations were operation cost and separation efficiency. However, many researchers have improved these beneficiation technologies in terms of cost and separation efficiencies producing clean coal product that meet the end user product specifications. This paper reviews recent developments in beneficiation technologies of coal fines and coal ultra-fines.

The article summarizes the achievements of the Cleaner Production (CP) project in China's pulp and paper industry from the perspective of industry and environmental regulators. Analyses of CP options have revealed that technology updates, equipment-related modifications, reuse and recycling were predominant improvement opportunities. Black liquor (BL) was identified as the top environmental problem facing China's non-wood paper industry. Insights about major bottlenecks that have hindered cleaner production within the paper industry are presented. The article explores the means of sustaining CP, both at the mill and at the national levels, with an emphasis upon the internal and external mechanisms fostering the continuous implementation of CP. Based on the analyses of CP activities in the paper industry, suggestions for further action are presented.

Life cycle assessments carried out to assess paper recycling have arrived at different conclusions, partly due to methodological differences in the inventory analysis. Important methodological issues include the definition of system boundaries, allocation, assumptions and choice of data. Forestry, electricity production, recycling and final waste management are important parts of the wood-fibre life cycle. This overview demonstrates the significance of different methodological problems, presents various solutions and offers recommendations. The starting point in an efficient and accurate assessment is the decision at hand, rather than the life cycle of the product investigated. To obtain the environmentally optimal wood-fibre system, recycling should ideally be assessed in connection with other waste management, forestry and energy policies.

The pollution of water resource and shortage of clean water have become increasingly severe, developing an urgent demand of reliable, efficient yet low-cost material for everyday water purification. In the present work, a superhydrophobic paper tissue-based SiO2/PDMS composite has been prepared for both oil absorption and water-in-oil emulsion separation. The fabrication process is quite simple since it takes the full advantage of tissue that has naturally strong capillary force of which allows the material to absorb oil from water much more rapidly and completely (>99.9%) even under harsh conditions. The study has shown the novel material is exceptionally efficient in separating water-in-oil emulsion under gravity but no need of extraneous pressure. A variety of emulsions has been proven with high flux (>2,000 L m−2 h−1) and high separation efficiency (>99.4%). It is believed that this study has proposed a highly reliable and efficient, low cost strategy in both oil absorption and water purification, which shed light on water treatment of both civil use and industry.

By-product utilisation has been recognised as a promising cleaner technology has attracted intense attention from both academic and industrial fields in the last decade. Industrial society is currently experiencing constraints imposed by our resource system by improving existing processes or finding newer way of waste utilisation. Waste and by-product streams from existing industrial sector (e.g. paper and pulp industry, meat industry) could be used as renewable resources for production of useful artefacts. This article mainly features recent research progress towards the utilisation of by-product in leather processing. This study was carried out to evaluate the propriety of using by-product black liquor from paper and pulp industry as filler in leather processing. Chemical modification of the black liquor has been performed to sustain a good compatible between the chemicals and also to improve the diffusion of black liquor into the leather substrate. The modification of black liquor was done by means of pH adjustment. Effect of filling nature of black liquor on strength property, softness nature, related morphological changes, and the dyeing property of the leather samples were thoroughly investigated. The results reveal that chemical composition of black liquor modulated by the pH adjustment was found to have a strong influence on the overall performance of the leather substrate.

The limited water supply of the Metropolitan Area of Mexico City has become a challenge for local companies. The region's aquifer is listed as closed due to pressure on the water supply as a result of growth in manufacturing as well as increased domestic water use. The environmental, economic and legal benefits of a cleaner production scenario studied were highly encouraging; implementation of cleaner technologies reduces water extraction by up to 16 times. While initial investment is high, the internal rate of return rate is approximately 35% per year, implying a three year return on initial investment. Under this scenario, the business complies with environmental regulations, avoiding great amounts of water extraction and future wastewater discharge, thus conserving this vital resource. This study proves what Silvo et al. (2009) states that In the longer run the combination of the Integrated Pollution and Prevention Control permit approach with other regulatory and voluntary policy instruments taking into account the results of system assessments such as Life Cycle Assessment could potentially produce eco-efficient solutions. Thus, for this industry, cleaner production pays off in the long run.

Product-oriented policies gain more and more attention in environmental policies. In this framework, we studied cases (here presented only housing and computers and paper) in a life cycle perspective in order to determine their environmental impacts (in terms of GHG emissions, resource use and waste production) over the period 1990–2010. We also evaluated their potential for improvement up to 2010 by applying product-oriented strategies. We identified clear technical (theoretical) potential for improvement, especially for housing, packaging and computers and paper in offices. We then carried out a Delphi-based survey among stakeholders in order to investigate potential measures.

An Environmental Management Accounting (EMA) framework is applied to the 2000 year-end financial report for the Mackenzie Paper Division paper mill owned and operated by Abitibi-Consolidated Inc. of Montreal, Quebec. A conventional reading of the obvious environmental costs from this financial report is Cdn$2,196,838. This figure is derived from an analysis of effluent treatment costs and other line item environmental costs. There is no “environmental account” category that breaks out either costs or the mass balance of inputs and outputs. For the most part, environmental costs are rolled up into overhead accounts such as administration, infrastructure and materials accounts. Application of the EMA framework is based on assigning environmental costs to one of four categories for which a tentative breakdown is as follows: (1) waste and emission treatment costs ($3,348,902); (2) prevention and environmental management costs ($270,109); (3) material purchase value of non-product output costs ($946,799); and (4) processing costs of non-product output ($2 92,943). There is also a category called Environmental Revenues, of which none were reported. Conservative estimates thus place the total environmental costs at $4,858,753. What is significant about this result is that the environmental costs under EMA are at least twice as much as would normally be reported. This supports the view that environmental costs are much higher than generally considered and makes it clear that many important environmental costs as well as benefits are “hidden” in other accounts. More studies of a similar design are required to confirm the validity of the EMA methodology reported here.

An approach based on the characterisation of individual operations by water demands and sources has been utilised to study an operating integrated pulp and paper mill. The search for novel whitewater network configurations as a function of specified process constraints and objective functions was done by means of a genetic algorithm coupled with linear programming. Potential solutions are derived from an initial superstructure representation which embodies all possible source and demand connections by an evolutive process akin to natural selection and adaptation. Various objective functions were investigated. Innovative strategies have been identified and are being considered for implementation.