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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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 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

Recovered paper is one of the major raw material for recycled papermaking industry. In China, the domestic recovered paper recycling system is incomplete and the amount of recyclable recovered paper cannot satisfy the papermaking demand. Therefore, the recycled papermaking industry is extremely dependent on imported recovered paper as their raw fiber source. In 2018, Chinese government announced a ban on unsorted recovered paper and tightened the import quota for recovered paper, which resulted in a dramatic drop in the importing amount of recovered paper. It is an urgent issue to explore alternative production routes that are more economical and environmentally friendly. Herein, life cycle cost assessment is used to compare and analyze the recycled papermaking industry based domestic recovered paper and three alternatives (including straw, imported deinked pulp and imported wood pulp) as the raw materials. The results show that the life cycle cost of domestic recycled paper based recovered papermaking is significantly lower than the other three alternatives, whereas its external cost is higher than that of the production routes based on the imported deinked pulp and imported wood pulp. With the increasing price of the domestic recovered paper, imported deinked pulp is the trend of recycled papermaking industry in China.

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.

Disposable paper cups comprise typical single-use plastic items, as they are lined internally with a thin plastic coating for waterproofing. They are consumed at a staggering rate worldwide, with the UK alone consuming around 7 million cups daily, thus annually producing around 30,000 tonnes of paper cup waste. Contrary to popular belief, less than 1 in 400 paper cups is currently recycled in the UK, which is in stark contrast to the waste hierarchy and the European Commission’s ambitious Circular Economy Action Plan. Paper cups typically end up in landfill sites or even improperly disposed of, contributing to (micro)plastic waste and potentially polluting the world’s oceans. The implications of the latter are not fully known yet and cannot be quantified by existing life cycle impact assessment methods. By employing the life cycle assessment methodology, UK’s annual carbon footprint from paper cup consumption was found to be 75 kt of carbon dioxide equivalents, which is similar to that of manufacturing 11,500 mid-size passenger cars. Globally, their environmental footprint was found to be comparable to that of some 1.5 M average European inhabitants, indicating the nature and extent of the single-use plastics problem, which paper cups are just a typical example of. Paper cup recycling could reduce this environmental footprint by up to 40%, whereas switching to reusable cups appears to be more environmentally sustainable, achieving a threefold reduction in carbon emissions, which at global scale is more than twice Malta’s annual carbon footprint. Results indicate that consumerism along with small daily choices, such as using reusable cups or bags instead of their disposable counterparts, could play a huge role in climate change. At policy level, no concrete measures to curb the superfluous consumption of paper cups, as well as of other single-use plastic items that are becoming increasingly ubiquitous, have materialised. Furthermore, it appears that decision- and policy-makers tend to step in to curtail wasteful and polluting practices only when environmental problems have started to generate widespread concern, instead of undertaking preventative policy measures.

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.

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.

Recycling is generally recognized as a key component of strategies to achieve improved resource efficiency and reduce the environmental burden associated with resource use. However, to maximize the net benefits offered by recycling, one must understand the system-wide effects of substituting primary materials with recycled materials and how those effects vary under alternative strategies. Consequential life cycle assessment (cLCA) approaches to evaluate the impact of increasing use of recycled materials require identification of grades and sources of scrap materials used at the margin. Various grades of recycled materials differ in their substitution possibilities and supply limits. However, most studies of cLCA for material recycling overlook these aspects and typically assume a fixed set of marginal activities. This study develops a model to describe the resource consumption behaviors of material producers and the resulting cascade of material flows for the case of the United States (US) pulp and paper industry. We observe that grades and sources of scrap materials used at the margin dynamically change so as the resulting environmental impact when demand for recycled containerboard products increases. The results show that the greenhouse gas (GHG) emission savings effect of using recycled materials can be considerably larger when marginal recovered fiber comes from additional recovery from landfill rather than being diverted from the export market. Also, the results show that the behavior of international trade partners for recovered paper may offset GHG emission savings from the domestic replacement of virgin pulpwood with recovered paper. Most importantly, such behaviors are dependent on grades used at the margin. The developed model and results can help inform the US pulp and paper industry, policymakers, and other stakeholders about the system-wide effects of increasing use of recovered paper.

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.

Research has revealed the existence of an energy-efficiency gap – the difference between optimal and actual energy end-use, suggesting that energy efficiency can be improved. Energy management (EnM ...

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.

Social life cycle assessment (S-LCA) is a tool to address social impacts from a life cycle perspective. This work presents the first S-LCA of the Portuguese pulp and paper sector. It presents the social risks and the positive social impacts of the sector, which have not been extensively covered in the scientific literature. Two different approaches were used to compile the social life cycle inventory based on input-output analysis. Approach 1 was based on impact analysis of changes in added value. Approach 2 was based on structural path analysis, supporting the disaggregation by production levels (or tiers). The functional unit was the production of 1 United States Dollar in the Portuguese pulp and paper sector. In the social life cycle impact assessment, the social risk assessment was conducted using the Social Hotspots Database. The positive impacts were addressed considering indicators of employment and remuneration, namely total employment, number of employees, labor compensation, and compensation of employees. Based on Approach 1, the results of the social risks showed the Portuguese pulp and paper industry, commerce and forestry sectors, and the Spanish forestry sector as the critical sectors. Based on Approach 2, Portugal and Spain continued to be the countries having the greatest social risks. Other contributions of countries were identified at different production levels, particularly China in tier 3. In both approaches, the stakeholder category ‘worker’ was the most critical. Regarding the positive social impacts, Approach 1 showed that Portugal and Spain contribute to the highest employment level linked to the pulp and paper, commerce, and forestry sectors. Approach 2 supported the differentiation of employment and remuneration at different production levels. Tier 2 (direct suppliers) presented the highest employment level and people engaged and the lowest remuneration level. The results showed that Approach 1 provides a faster and more aggregated assessment of social risks and positive social impacts. Furthermore, Approach 2 allowed a more detailed evaluation, providing a better understanding of the social risks and positive social impacts on the supply chain. Thus, Approach 2 is encouraged for different applications since it produces a better understanding of where social risks and positive social impacts occur, providing better guidance for corrective measures and decision-making.

Papermaking enterprises are currently under both environmental pressure and economic pressure for sustainable development in China. Thus, the efficiency, effectiveness, and benefits of resource utilization need to be improved. High-consumption and high-pollution companies should manufacture paper using sustainable methods. This study highlights a resource value flow analysis from the circular economy perspective, developing an extension of material flow cost accounting and modifying it by accounting for environmental damage as well as economic benefits. With reference to the Plan-Do-Check-Act cycle, this specific case study was conducted to verify the comprehensive utility of resource value flow analysis by establishing decision-making prioritization according to the dualistic diagnosis of “internal resource loss–external environmental damage costs.” In general, applying a resource value flow analysis can both reduce resource consumption and minimize environmental damage, enhancing the sustainable development of a process industry with limited resources.

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.

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.

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.

In a circular economy, extended producer responsibility (EPR) is a regulatory approach that accounts for all environmental costs associated with a product throughout its life cycle. When considering the EPR, the regulator must (1) design an integrated framework for different stakeholders and (2) provide effective policies to create financial incentives to accelerate the circular system. Recycling funds and subsidies are the most prominent financial strategies that can either encourage or curtail the flows of recycled products. In Indonesia, a few companies provided recycling bonus s to their customers as incentives to increase the recycling rate. However, the recycling rate was not as effective as expected by the enterprise because recycling was practiced by a limited number of companies, rendering it economically unviable. The enterprises hope the government could develop a recycling fund system. In order to develop the recycling fund system, a system dynamic model was proposed and simulated to optimize the recycling funds and subsidies based on decentralized reverse supply chains. Although it is not a novelty model; however, the research show a very significant results for the government in Indonesia. This enabled a more precise, well-planned, and sustainable decision-making process for the EPR. In addition, by utilizing the system dynamic model with different scenarios in a real case study (aseptic paper packaging waste), we found that the capacity of the recycler could become the reference for the funds to be paid by the importer-producer group, wherein the recycling rate will increase with an increase in the recycling fund.

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.

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.

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.

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.

Indonesia’s internationally- and domestically-significant pulp and paper industries source their feedstock from tree plantations. A suite of regulatory (Indonesian Sustainable Production Forest Management Certification and Timber Legality Verification) and market instruments (forest certification) have been introduced to promote sustainability and legality of production from tree plantations, and some producers have also adopted other voluntary sustainability measures. This study investigates sustainability and legality compliance by actors in an Indonesian pulp and paper value chain as a case study of environmental innovation. Results are based on primary fieldwork along segments of the value chain, and analysis of audit reports and other publicly-available information. The value chain sources fibrewood from tree plantation concessions and pallet wood from a variety of suppliers. Audit reports suggest high levels of compliance with sustainability and legality requirements, but our research suggests that these reports might not reflect some area of poor performance and non-compliance. We identify weaknesses in the design of regulatory systems, and in auditing and monitoring processes, as the principal reasons for these deficiencies. Drawing on relevant theory and on practice elsewhere, we suggest that compliance and sustainability can be improved by addressing key areas of regulatory silence, by shifting auditing to be more performance-than paper-based, by strengthening independent monitoring from civil society, by increasing the frequency of witness auditing from the National Accreditation Board, and by fostering synergies between regulatory instruments and voluntary forest certification. These changes would improve the effectiveness of regulatory and voluntary instruments to promote cleaner production in Indonesian pulp and paper value chains.

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 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.

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.

The increase in mining-related social conflict around the globe can only be partly attributed to broader societal factors such as communities becoming more assertive, empowered and connected. The aggressive growth strategies of mining companies have also been a contributing factor, as this has taken them into areas which are socially and politically more challenging and has increased the potential for conflict with other land users. While mining companies may have embraced the language of ‘trust’, ‘shared value’ and ‘partnership’, they remain locked into a business model that periodically threatens these values. Given the constraints of this business model, there has to be a practical focus on creating stronger external, as well as internal, drivers for companies to improve how they engage with communities and other stakeholders.

[EN] Current wastewater treatment plants (WWTPs) paradigm is moving towards the so-called water resource recovery facilities in which sewage is considered a source of valuable resources. In particular, urban WWTPs are crucial systems to enhance phosphorus (P) recycling. This paper evaluates the implementation of a P-recovery system in Calahorra WWTP combining the operation of a new sludge line configuration coupled to a struvite crystallisation reactor at demonstration-scale. This new configuration consisted in the elutriation in the gravity thickener of the mixed sludge contained in the mixing chamber in order to reduce the phosphate load to the anaerobic digestion. The results indicated that the P available in the primary sludge overflow was nearly five times more than the obtained for the conventional configuration (1.88 vs. 0.39 gP/kg sludge treated), and the uncontrolled P precipitation inside the anaerobic digester was reduced by 43%. Regarding the total P entering the WWTP, 19% of the total P could be recovered with the new configuration proposed in comparison with 9% in the previous conventional configuration. The average recovery efficiency in the crystallisation plant was 86.9 0.4%, yielding a struvite recovery of 8.0 +/- 0.6 kg/d (0.67 +/- 0.04 kg/m(3) fed to the crystalliser). The potential struvite production with the new configuration would be around 41 kg/d (15 t/y) crystallising the thickener supernatant which could be increased up to around 103 kg/d (38 t/y) treating all the P enriched streams (thickener supernatant and centrate streams). The paper demonstrates that WWTPs can contribute to reduce P scarcity, resulting in environmental and economic benefits. (C) 2019 Elsevier Ltd. All rights reserved., This work was co-financed by the European Financial Instrument for the Environment (LIFE +) as part of the PHORWater Project (LIFE12 ENV/ES/000441). The authors also like to acknowledge the support received from Consorcio de Aguas y Residuos de La Rioja and from EDAR del Cidacos (Calahorra).

Industrial productivity is often judged solely by the primary product's marketability, while opportunities for secondary products derived from process by-products are often overlooked. In paper mills, large volumes of moisture-rich paper mill residuals (cellulose sludge) are produced, for which commercial use is currently difficult. Port Hawkesbury Paper LP, Port Hawkesbury, Nova Scotia, produces over 7 t/hr of waste sludge with a seasonally-dependent dryness ranging from 25 to 38% (w/w). Various chemical or mechanical dewatering options exist; however, knowledge of the unique sludge composition and properties is essential to predicting how the product will react under each method. Sonication, Fournier rotary press technology, freeze/thaw cycling, and gravity drying were among the dewatering opportunities briefly explored outside of the chosen method, acidification. Notably, many industries utilizing dewatering technologies may not be producing value-added by-products, while geographic and climatic placement may limit processes which are possible for others. In the present study examining enhanced end-use value, further dewatering occurred through a comparative in situ experiment contrasting sulfuric acid and ferric sulfate acidification (direct acid injection into sludge). While both proton donors acidified the sludge and decreased moisture content, sulfuric acid was the more cost-effective option, yielding an ∼4% increase in dryness, with commensurate economic and environmental benefits.

Rice husk is an important biomass residue derived from the production of rice. Rice husk contains silica (10–20 wt%) and lignocellulose (cellulose, 15–25 wt%; lignin, 10–20 wt%). The lignocellulose components in rice husk are potential carbon sources for functional carbon materials. In this work, we propose a general comprehensive green utilization strategy for the preparation of lignin-derived hierarchical porous carbon (LHPC) and cellulose-paper-based separator using the lignin and cellulose components inside rice husk, respectively. The obtained LHPC and cellulose paper separators were used as pivotal components for the fabrication of high-rate electrochemical zinc ion capacitors. Meanwhile, the silica and potassium sources in this comprehensive route were recycled as nano-sized SiO2 particles and pure KCl powders. This work constitutes a general route for the green utilization of rice husk biomass. This work opens a green avenue for the effective utilization of renewable biomasses to develop functional carbon materials and pivotal components of electrochemical energy storage devices.

Tanneries boost the local economic development, but lead to severe environmental pollution; hence, improving the environmental assessment of this sector is essential. In this paper, the Life Cycle Assessment method was applied to estimate impacts on the environment and human health of retanning, fatliquoring and dyeing. The analysis was performed from a “gate to gate” perspective. Moreover, sulpho chlorinated paraffin and epoxidized vegetable oil have been evaluated as alternative fatliquoring agents. The production of electricity required for the rotation of drums gives the main contribute to most of the impact categories, followed by the azo-dye production. Emissions of sulfur dioxide, nitrogen oxides, manganese, vanadium and nickel associated to power plants are the main sources of terrestrial acidification and particulate matter formation, as well as of human and marine toxicity (4.48·10−1 and 1.09·10−2 kg of 1,4-DBeq kg−1 crust leather, respectively). Nitrate loads from wastewater treatment and oxidative treatments affect heavily marine eutrophication (6.9·10−1 g N eq kg−1 crust leather). The use of epoxidized vegetable oil would affect human toxicity, ecosystem, metal and water resources depletion more than the use of sulpho chlorinated paraffin, mainly due to pesticides distribution and other cultivation practices. Phosphate and nitrate releases due to fertilization determine the high impact on the categories freshwater and marine eutrophication. Progress in increasing the conversion efficiency is demanded, but overall focus must be made on the substitution of fossil fuels with cleaner alternatives. The transition towards a circular economy is encouraged; increasing rates of reduction, reuse, recycle and recover of solid waste and tannery effluents are recommended. Agricultural practices with a reduced consumption of phytosanitary products and mineral fertilizers, alternative to conventional farming, would strongly contribute to increase the sustainability of epoxidized vegetable oil as alternative fatliquoring agent.

Organic micropollutants like pharmaceuticals, personal care products, pesticides and industrial chemicals have received an ever growing attention due to their adverse ecological effects in natural water bodies. A promising technology to remove the micropollutants from the wastewater is biocatalytic treatment using oxidoreductase enzymes. In order to improve removal efficiency and feasibility, the focus has been on developing enzyme-mediator systems and immobilisation techniques. Nonetheless, since oxidoreductase enzymes often promote coupling reactions, enzymatic reactions do not necessarily result in simpler compounds. Thus transformation products, which might be in equally or even more hazardous pollutants, can be still present in the wastewater after treatment. Therefore, the toxicity and ecological effects of the reaction products have to be investigated rigorously to ensure that the treatment mitigates the environmental and health related impacts.The objective of this paper is to give an overview of research carried out with oxidoreductase enzymes to treat different organic micropollutants and their mixtures along with real wastewater and to collect available information on different techniques, transformation products and toxicity. Though in most cases the reviewed enzymatic treatment methods resulted in less toxic effluent, the application of mediators, while facilitating higher transformation rates, increased the level of toxicity. Hence, it was concluded that the suitability of biocatalytic methods should be assessed from the perspective of toxicity beside the removal efficiency in order to allow the upscaling of the technology to a feasible and sustainable wastewater treatment solution.

There is growing interest in making printing inks more sustainable, and lowering the overall carbon footprint of the printing industry. A recent surge of research activity has emerged to develop “green” inks with bio-based solvents and binders, but little attention has been given to replacing the pigments that give inks their distinctive color. In this study, flexographic inks were formulated by replacing carbon black with a more sustainable biochar pigment derived from recycled paper, and fast growth cycle wood pulp. Obtained from fossil fuel sources, carbon black imparts high quality black prints, but at a significant environmental cost. Biochar, derived from recycled and renewable resources, has the potential to replace carbon black in many applications. Canceled United States currency stock was pyrolyzed at 1600 °C to produce a black biochar. Eastern White Pine (Pinus strobus) was selected for comparison, and converted to biochar at 550 °C and 1600 °C. Each biochar was functionalized and formulated into a simple ink composition optimized for flexographic printing. Prints exhibiting reflective optical densities exceeding 1.0 with excellent tone reproduction were obtained. Comparable print quality was achieved on both coated and uncoated paper substrates. Although further work would be required to fully optimize a biochar ink to match current print industry standards, a viable pathway for sustainable black ink development with good black density derived from recycled resources has been demonstrated. Our results indicate that it is possible to replace fossil fuel-based carbon black with biomass derived biochar, potentially resulting in cleaner production of flexographic printing inks.