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Made available in DSpace on 2022-04-29T08:31:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Organization and planning of reverse logistics networks make sustainable processes more efficient. Thus, an important sector for connecting the collection and waste paper recycling echelons is the intermediate center. In this study, a Mixed Integer Linear Programming model, which is multi-objective, multi-product, multi-level and multi-period, was developed to optimize the waste paper logistics processes of intermediate centers. The formulation includes the following echelons: collection, considering vehicle routing with different capacities; inventory of non-baling materials; baling sorted waste and inventory of bales; selling bales; disposal of non-recyclable waste. The aims of the model include: maximizing the collected waste; minimizing distances; maximizing both the production and sale of bales, and minimizing costs. According to research carried out in the literature, the developed model is a new proposal and to implement it, the Weighted Goal Programming and Revised Multi-Choice Goal Programming approaches were used to deal with multiple objectives and incorporate uncertainty into the quantity of waste available for collection. To analyze the proposed model, computational tests were executed with instances based on real data from a Brazilian company in the sector. For all performed tests, General Algebraic Modeling System 23.6.5 modeling language and CPLEX 12.2.0.2 solver were used for modeling and optimization. The results show that this study presents formulation and technological approaches that represent real situations and provide competitive solutions to the problem. Sáo Paulo State University “Júlio de Mesquita Filho” [Universidade Estadual Paulista Júlio de Mesquita Filho] School of Engineering of Guaratinguetá [Faculdade de Engenharia de Guaratinguetá] Production Department, Av. Ariberto Pereira da Cunha, 333, Portal das Colinas Agulhas Negras Military Academy [Academia Militar das Agulhas Negras] Rodovia Presidente Dutra, km 306, s/n Escola Preparatória de Cadetes do Exército Avenida Papa Pio XII 350 Jardim Chapadão Campinas - SP Brazil, Avenida Papa Pio XII, 350, Jardim Chapadão, Campinas - SP Sáo Paulo State University “Júlio de Mesquita Filho” [Universidade Estadual Paulista Júlio de Mesquita Filho] School of Engineering of Guaratinguetá [Faculdade de Engenharia de Guaratinguetá] Production Department, Av. Ariberto Pereira da Cunha, 333, Portal das Colinas

This work investigates the influence of blending waste paper and cement at fixed proportion with varying proportions of chicken feather fiber (CFF) and wood saw dust (WSD) as reinforcements. Samples produced were tested for flexural properties and water absorption potentials. The outcome showed that with increasing CFF content and reducing WSD content, water absorption reduced while flexural strength, modulus of ruptures (MOR) and modulus of elasticity (MOE) increases. MOR and MOE were at peaked when the ratio of CFF to WSD was 3:2 while flexural strength reached it crescendo at 4:1 of CFF to WSD. It was noticed that higher CCF content from 3 to 5 wt% gave better results in most of the investigated properties compared to WSD. Therefore, it was concluded that low quantity of WSD is needed to form a synergy with CFF in order to achieve optimum results. Well dispersed CFF-WSD phase in waste paper-cement based composites was observed to be responsible for the enhancement in the investigated properties.

7 figures, 4 tables.-- Supplementary information available.-- © 2022. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/, Developing chrome-free and sustainable tanning agents is extremely important to the sustainability of the leather industry. Herein, we have synthesized an Al-Zr-oligosaccharides tanning agent via a simultaneous degradation and oxidation of cellulose in waste paper. The influence of the temperature and the concentrations of AlCl3 and H2O2 during the synthesis were thoroughly investigated on the properties of the tanning agent and the leather produced. The synthesis temperature and the concentration of AlCl3 were the factors primarily affecting the effective depolymerization of cellulose. They controlled the conversion of waste paper into oligosaccharides with an appropriate molecular weight to efficiently penetrate the leather matrix. In parallel, the H2O2 concentration substantially influenced the tanning performance of the Al-Zr-oligosaccharides, diminishing the chromaticity of the tanning liquid via oxidation and promoting the conversion of C2/C3/C6-OH moieties into -CHO/-COOH. These functional groups increased the surface charge of the oligosaccharides allowing more effective coordination with Al/Zr, which facilitated the penetration of Al/Zr species into the leather matrix. Once inside the leather matrix, Al and Zr were released and reacted with the collagen fibers in leather, which resulted in effective leather tanning. The process optimization revealed that up to 57% of waste paper could be converted into a low-chromaticity (4350 AU) liquid hydrolysate with the synthesis conducted at 177 °C in a system comprising 47 mM AlCl3 and 5 vol% H2O2. The application of this liquid for tanning provided leather with a shrinkage temperature (86.5 °C) sufficiently high for commercial applications. These excellent results, combined with the intrinsic green nature of our approach, exemplify a step forward to simultaneously reduce pollution and hazards in leather industries giving a second life to waste paper., This work is financially supported by the National Natural Science Foundation of China (22078211). Javier Remón acknowledges the Spanish Ministry of Science, Innovation and Universities for the Juan de la Cierva (JdC) fellowship (Grant Number: IJC2018-037110-I) awarded.

The study presented here shows the influence of River Sand, M-sand and Admixtures on the properties of concrete which were analyzed. The effect of admixture content on concrete properties was evaluated with two types of admixtures independently. Metakaolin (MK) content was varied at 0%, 5%, 10% and 15% whereas Waste Paper Sludge Ash (WPSA) content was varied from 0%, 6%, 12% and 18%. Response surface methodology was employed to optimize the compressive strength, permeability and sorptivity of concrete when both admixtures (MK+WPSA) were varied simultaneously. The relationship between the concrete properties and level of materials added was derived using a Face Centered Central Composite Design with three levels and three factors. Based on desirable properties obtained in experimental part of the study, the factors considered in the design was M-Sand (0%, 50%, 100%), MK (0%, 5%, 10%), WPSA (0%, 6%, 12%). From the experimentally obtained data, prediction models based on regression analysis were developed which enables the establishment of response contours showing the interaction between the different parameters investigated. The contour plots were overlaid to distinguish the combination of proportions that gives ideal performance of concrete for water-repellency and strength

In this study, the colemanite (a natural calcium borate mineral, NCBM) and Fe2O3 used as a catalyst on the liquefaction of Elbistan Lignite (EL, which has the most reserves in the east of Turkey). The liquefaction experiments were carried out at the reaction temperature of 400 °C, the reaction time of 90 min, the solvent/solid ratio of 3/1, stirring speed of 400 rpm, and initial nitrogen gas pressure of 20 bar. Fe2O3 and colemanite were together prepared as a new catalyst. Research has been made the recent observation that the highest liquefaction product yields, especially from a series of valuable fractions, obtained, with the highest mineral content of lignite. According to that model colemanite mixed with Fe2O3 to decide if the mineral content effect on total conversion if mineral substances added separately from coal. Fe2O3 selected as the most suitable catalyst type. To understand how to affect colemanite (as an economical catalyst source and also has high reserves in Turkey) as a catalyst on the liquefaction of EL with waste paper. The experiment conditions fixed and so compared due to the total conversion values. Unlike previous studies, this study was 67.1% of the total fluid conversion without catalyst, but this value increased to 77.6% when 15% NCBM catalyst was used. The total conversion was up to 83.8% with the catalyst concentration of 3% Fe2O3. On the other hand, when only 3% of Fe2O3 was used, the total conversion was only 75%. As a result, the mixture of NCBM and Fe2O3 increased the liquefaction efficiency by 15% by the synergistic effect.

One of the most important problems in dark fermentative hydrogen production is the need for the regulation of the ambient pH due to the formation of volatile fatty acids. For this purpose, alkaline chemicals are usually used; however, alkaline addition to the media increases salt formation, which negatively affects microbial activity. In this study, pH adjustment was performed by providing direct current as an alternative to alkali addition. Experiments were carried out batchwise and electricity was only applied to neutralize the acidic pH value. The waste paper hydrolysate was used as a substrate and the effects of applied voltage (0.25-3 V), substrate concentration (4.8-41.2 g/L at 1 V) and electrode distance (0.3-1.3 cm at 1 V) on hydrogen production performance was investigated. Voltages less than 1 V required too much time to keep the pH convenient and voltages more than 1.5 V adversely affected hydrogen production performance. Providing direct current to the fermentation media significantly reduced the adaptation phase. Conditions for optimal pH adjustment and hydrogen production were obtained at 1 V, 20 g glucose/L and 0.5 cm electrode distance. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

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

The development and production of new materials requires advanced analytical characterisation to explain the relation between the physico-chemical structure of the material and its properties. Highly integrated microelectronic structure analysis of surfaces with laser beams and X-ray fluorescence aided devices are found to be helpful for providing important information, including the interrelationships between physical, chemical, mechanical and durability characteristics of the new developed products. In most instances no single technique provides all the needed information and hence simultaneous application of several techniques becomes necessary. This study was aimed for hydration analysis, characterization and evaluation of a new novel non-Portland binder (NPB) with waste paper sludge ash (PSA) using FTIR and TG/DTA. The progressive formation of hydration products within the non-Portland binder was identified and their microstructural characteristics were analysed. The stable and non-expansive nature of secondary ettringite formation was also identified after a period of 365 days curing.

Chemical Looping Combustion (CLC) CO2 capture technology can be used to recover energy from municipal solid waste (MSW). In this study, techno-economic analysis of CLC of waste paper, PVC and their blends for electricity and heat generation was carried out. The process includes the chemical looping combustion section, carbon capture section and lastly, electricity generation section, and this was simulated using Chemcad software. Four scenarios were evaluated; IG-CLC (In-situ Gasification Chemical Looping Combustion) with electricity production only, and with combined heat and power (CHP), Chemical Looping Oxygen Uncoupling (CLOU) with electricity production and with combined heat and power (CHP). Based on a net capacity of 150 MW, the effect of waste paper, PVC and its blends on its net efficiency and LCOE was investigated for all four scenarios.

Focusing on eco-friendly materials, cellulose nanocrystal (CNC) extracted from office waste paper was used to reinforce waterborne polyurethane (WPU) with varying content by two incorporation routes including blending method by sonication after WPU synthesis (BCNC/WPU) and the alternative in-situ during the WPU synthesis process (CNC/WPU). The results showed that new interaction between CNC and WPU through hydrogen bonds in the interfacial area was formed and CNC reinforced hard segments effectively. However, the interaction in BCNC/WPU was not as stronger as that in CNC/WPU. Besides, CNC improved thermal stability of WPU remarkably, especially BCNC/WPU. The addition of CNC caused a delay around 50 °C in the start of the degradation process, and a delay of 5–18 °C and 2–20 °C in the temperatures at 10 and 50 wt% weight loss, respectively. These eco-friendly and biodegradable novel materials have potential applications in medical and biologic fields.

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

In this paper, a new metal-free photocatalyst (g-C3N4/C) coupled by graphitic carbon nitride (g-C3N4) and biomass carbon (waste paper used as carbon source) has been successfully synthesized. The g-C3N4/C exhibits obviously improved photocatalytic activity for degrading tetracycline, the degradation rate is more than 80%. It is more than four times than that of pure g-C3N4. Based on the structure and morphology characterization, the as-prepared g-C3N4/C represents a porous structure, which can provide a large surface area, increase the transmission route of photo-generated carriers and suppress the charge recombination. In addition, the capture experiments and ESR exploration show that both the h+, ·OH and ˙O2−play the important roles in this metal-free photocatalytic reaction. More importantly, our work not only designs a better photocatalytic material, but also provides a new thinking for, waste recycling which coincides with the concept of sustainable development

Bio-deinking is an environmentally friendly process that improves the pulp and paper properties and reduces chemical consumption during the recycling of waste paper. This study was performed to evaluate the efficacy of enzyme by Penicillium sp. AKB-24. Chemical deinking of MOW showed freeness (CSF), pulp brightness (ISO), deinking efficiency, and dirt count by 426±4 ml, 75.55±0.1%, 82.13±0.7%, and 733±24 mm2/m2 respectively at optimum repulping parameters. The physical strength properties including burst index, tear index, tensile index and double fold numbers were found 2.97±0.14 kPa.m2/g, 11.14±0.61 mN.m2/g, 46.60±1.99 N.m/g, and 36±2 respectively during chemical deinking of MOW. The deinking chemicals including NaOH, Na2SiO3, and H2O2 were replaced with crude enzyme by Penicillium sp. AKB-24 during enzymatic deinking of MOW. Enzymatic deinking of MOW resulted in an improvement in pulp freeness by 18.30% compared to chemical deinking while the dirt count value decreased by 32.60% during enzymatic deinking of MOW. Physical strength properties such as burst index, tensile index, and double fold numbers were improved by 16.07%, 14.54% and 8.57% respectively while tear index was decreased by 11.61% during enzymatic deinking of MOW compared to chemical deinking.

Biowastes, such as cow manure, waste paper, and wood waste, are recognized as an essential source of renewable energy, and their importance increased significantly over time. However, the insufficient supply of biowastes for commercial thermochemical conversion processes is a major problem that needs to be addressed. Therefore, the co-utilization of biowastes and coal has been developed globally. In this study, we investigated the feasibility of biowaste and coal mixtures in an ethanol conversion process. A commercial-scale thermochemical process consisting of a dual fluidized bed gasifier, compressor, tar reformer, catalytic reactor, and auxiliary facilities was used and analyzed. In particular, the effects of material costs including both transportation and collection costs of biowastes and mix percentages on the economic value of synthetic ethanol were analyzed. In addition to the limitations of biowaste collection, the scale of co-utilization processes could be a critical factor for the commercialization of converting biowaste and coal mixtures to ethanol.

This study aims to examine the economic and environmental benefits of recovered paper and potential contribution of the recovered paper to the Kingdom of Saudi Arabia (KSA) Vision 2030. The Vision 2030 is an inclusive development policy, recently launched, with the objectives to build the best future for the country. The Vision 2030 is based on three ambitious goals: making the country a vibrant society, a thriving economy and an ambitious nation. It is estimated that by 2030, 5.05 million ton of waste paper would be recovered in the country. About 11.3 billion SAR (US $3.01 billion) would be added to the country’s GDP and would create about 16,536 new jobs if the recovered paper industry is built in the country. Moreover, a net environmental benefit of 9.6 million crude barrel oil savings and 4.5 million ton of CO2 savings from GHG emissions could be achieved by 2030 only from the paper waste recovery in the country. The potential benefits of paper waste recycling in KSA highlight the needs of effective measures to optimize the economic and environmental opportunities inherited in the waste paper industry. These measures should focus on capitalizing the local waste paper processing industry, restrict the export of raw waste paper materials, and enhance the waste paper collection process and quantity.

Environmental issues, legal requirements, and economic benefits of recycling activities lead to the development of reverse logistics operations and waste management. The current research considers a closed-loop supply chain for a cardboard recycling network including multiple suppliers and production stages. A mixed integer linear programming model is proposed to optimize the paper and cardboard recycling network, and a robust optimization approach is utilized to deal with demand uncertainty in this network. The model maximizes the total profit. It considers the operation, transportation, purchasing and holding inventory costs as well. Moreover, to illustrate the application of the proposed model, a real-world cardboard closed-loop supply chain design is investigated. The proposed model considers the option to open a new recycling center in the current network. The proposed model determines the optimal quantities of the waste paper, paper, sheet and cardboard that flow in this network. Finally, the computational analysis indicated that the proposed model provides efficient solutions for the studied cardboard closed-loop network.

Hybrid composites were prepared with jute fabric and un-shredded newspaper in polyester resin matrix. The experiment was designed 1:2 weights ratio jute and unshredded newspaper to have 42 (w/w)% fibre content hybrid composites and two different sequences jute/paper/jute and paper/jute/paper of waste newspaper and jute fabric arrangement. Reinforcing material is characterized by chemically, X-ray diffraction methods, Fourier transform infrared spectroscopy and tensile testing. The tensile, flexural and interlaminar shear strength and fracture surface morphology of composites were evaluated and compared. It was found that tensile and flexural properties of the hybrid composite are higher than that of pure paper-based composite but less than pure woven jute composite. The hybridization effect of woven jute fabric and layering pattern effect on mechanical properties of newspaper/woven jute fabric hybrid composites were studied. The test results of composites were analyzed by one-way ANOVA (α=0.05), it showed significant differences among the groups.

The effects of N/C, P/C and Fe/C ratios on dark fermentative hydrogen gas production from activated carbon treated WPT hydrolysate were investigated using Box-Behnken statistical experiment design. N/C, P/C and Fe/C ratios were chosen as independent variables while the H-2 yield and SHPR were set as the objective functions. H-2 yield and SHPR functions were described by two quadratic model functions. The addition of a proper amount of N, P and Fe to the fermentation media was found to be essential to enhance the H-2 production performance. Linear and interaction terms of N/C and Fe/C did have a significant effect on the H-2 yield in the model function. However, the SHPR was significantly affected by the linear and interaction terms of N/C and P/C. The most convenient N/C, P/C and Fe/C ratios resulting maximum H-2 yield (0.656 mol H-2/mol glucose) and SHPR (241.64 mL H-2/g biomass.h) were determined as 0.05, 0.09 and 0.003 (w/w), respectively. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

This study assesses the impacts of the China-US trade war on the global forest product markets using the bilateral trade flow module of the Global Forest Products Model. Two alternative scenarios are compared to the business-as-usual situation: (1) the US charges 25% tariff on $200 billion of goods imported from China, which in return imposes differentiated tariffs on $60 billion of goods imported from the US; (2) the US raises the tariff rate from 25% to 30% and China adds extra tariffs on $75 billion of imported goods. It is found that China's imports of sawnwood and waste paper from the US and the US imports of plywood and other paper from China decreased significantly. Meanwhile, some of the trade flows between China and the US shifted to other parts of the world. Vietnam and New Zealand were the largest winners while Thailand suffered a relatively heavy loss. Product substitution occurred mainly in Asia and Europe, and price changes were within 10%. Overall, China benefited slightly, but the US experienced a loss. These findings have broad policy implications for international trade.

Office waste paper constitutes an excellent low cost and high quality fibre source for the papermaking industry. Limitations in the application of conventional deinking to such paper are related to negative environmental impacts chemicals can cause, hence enzymatic deinking is receiving growing attention. This study is focused on the investigation of the effect of cellulases application on the deinking of office waste paper. The methodology involved: preparation of samples, impregnation, repulping, enzymatic treatment, flotation, papermaking, and finally evaluation of optical properties. Five preparations, working under acidic and neutral conditions, were tested (Cellusoft CR, Cellusoft AP, Novozymes 342, Cellusoft L, Accelerase 1500). The added amount of each enzyme preparation corresponded to 150 FPU/100 g paper. It was observed that the deinking experiments using enzymes achieved generally better results in comparison with those in which the enzymes were previously deactivated. Despite the positive effect of activated enzymes as compared to deactivated, the application of enzymes appeared disadvantageous compared with the conventional deinking in terms of specks surface of the deinked paper sheets. Apart from the type of enzyme preparation itself, another critical factor affecting the effectiveness of the enzymatic treatment was the addition of nitric acid used to achieve acidic conditions for the optimum enzyme function. To this end, further study have to be performed on enzyme preparations functioning under alkaline conditions as well as on other paper types while the effect of enzyme amount to the deinking and the subsequent impacts on mechanical strength of produced papers may be also investigated.

In order to explore hydrothermal carbonization (HTC) behavior of municipal solid wastes (MSW), four typical components, waste textile, wood, paper and food, were employed to perform HTC and co-HTC process. The experiments were conducted at 240 ○C and 90 min with a 1:12 solid/liquid ratio, where blending ratios of 1:3, 1:1 and 3:1 with waste textile were investigated. As expected, the increase of fixed carbon and carbon content improved the fuel potential of hydrochar. The synergistic index (SI) analysis clearly indicated that significant synergistic effects occurred during co-HTC process. Specifically, all the SI values of hydrochar yield from co-HTC of waste textile with wood and paper were negative, while all SI values of hydrochar yield for waste textile with food were positive. Particularly, the SI values of fuel ratio for all hydrochars were positive which suggested co-HTC could promote to enhance the coalification degree of hydrochars. However, the undesirable increment of O content for hydrochars (derived from 75%waste textile-25% waste food and 50%waste textile-50% waste food) decreased the high heating value. The combustion behavior and nth-order kinetic model analysis showed that hydrochars derived from co-HTC rendered a more stable and lasting combustion profile.

Since 2013, the Chinese government has implemented a series of waste paper import regulations with the aim of improving the quality of imported waste paper. The purpose of this study is to investigate the impact of these new regulations on the quality of imported waste paper. The study analyzed the asymmetric effects and dynamics between China's domestic and imported waste paper prices and between import price and the quality of imported waste paper based on the asymmetric ARDL model. The results revealed that the Chinese and international waste paper markets were integrated and that both long-run and short-run asymmetries were presented in the relationship between these two markets. Furthermore, the results indicated that the quality of imported waste paper reacted differently to the positive and negative changes in import price, and a decrease in import price will lead to an increase in the quality of imported waste paper. China's waste paper import regulations weakened the integration relationship between the Chinese and international waste paper markets and caused the import price to drop. Therefore, it implies that China's new waste paper import regulations promoted the quality of imported waste paper, which is beneficial to the mitigation of environmental contamination.

Currently, the disposal of municipal wastes (paper, plastic, and coffee residue) is a problem due to increasing the amount of municipal wastes, global environmental problems, and high disposal cost. Here, we report the synthesis of carbon quantum dots from waste paper by different solvents by a conventional hydro-/solvothermal method for solving the environmental and disposal problems. The carbon quantum dots synthesized with waste papers have several advantages such as low toxicity, low cost, and eco-friendly. The prepared carbon quantum dots have main emission peak from 440 to 540 nm under 340–480 nm excitation. The prepared carbon quantum dots can be applied to easily prepare anti-counterfeiting ink and fluorescent flexible film because of their unique optical property and excellent chemical and photostability.

Wood pulp and wastepaper are all essential inputs in making paper and allied products. China has been the leading participant in the global fiber trade in recent years. In this study, China's import of wastepaper and wood pulp by supplying source was assessed through a two-stage differential production model. The analyses revealed that wastepaper imports were inelastic in both expenditure and price, the magnitude of price elasticity estimates became larger after considering the variation of total expenditure, and the substitution between wastepaper and wood pulp imports was limited. Rising imports of wastepaper had small effects in reducing the rapidly growing imports of wood pulp by China. Thus, the concern over environmentally detrimental effects of importing virgin wood pulp from countries with poor forest management practices will likely continue.

The household solid waste generated in Beijing is increasing quickly due to rapid population growth and lifestyle changes. However, there are no rigorous data on the generation and collection of recyclable household solid waste. The Beijing city government needs this information to establish policies and make plans for waste management. To address this need for information, we undertook the first comprehensive study of recyclable household solid waste for Beijing. We surveyed 500 families across sixteen districts in Beijing. We also analyzed the quantities, spatial distribution and categories of collected waste handled by permanent recycling centers and curbside recyclers for 340 of the 9797 city-defined residential areas of Beijing. From our results, we estimate that the total quantity of recyclable household solid waste was 1.805 million tons in 2013, and 72% of that was collected. The main generation categories were waste paper (24.4%), waste glass bottles (23.7%) and waste furniture (14.3%). In addition, we estimate there were 5.7 thousand permanent recycling centers and 22.8 thousand curbside recyclers in Beijing. The recycling rate of solid waste generated by urban households in Beijing was not low but varied significantly among different types of solid waste. The collecting capability of permanent recycling centers was inadequate. Urban residents had low awareness of some categories of solid waste recycling. The statistical system for waste management needed to be improved. Based on the problems mentioned above, the implications for solid waste management were discussed. We suggest accelerating the construction of permanent recycling centers and innovating the recycling modes. Meanwhile, it is also necessary to strengthen education on solid waste recycling and improve the recycling information statistics.

Paper product manufacturing involves a variety of chemicals used either directly in paper and pulp production or in the conversion processes (i.e. printing, gluing) that follow. Due to economic and environmental initiatives, paper recycling rates continue to rise. In Europe, recycling has increased by nearly 20% within the last decade or so, reaching a level of almost 72% in 2012. With increasing recycling rates, lower quality paper fractions may be included. This may potentially lead to accumulation or un-intended spreading of chemical substances contained in paper, e.g. by introducing chemicals contained in waste paper into the recycling loop. This study provides an overview of chemicals potentially present in paper and applies a sequential hazard screening procedure based on the intrinsic hazard, physical-chemical and biodegradability characteristics of the substances. Based on the results, 51 substances were identified as potentially critical (selected mineral oils, phthalates, phenols, parabens, as well as other groups of chemicals) in relation to paper recycling. It is recommended that these substances receive more attention in waste paper.

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.

For a paper manufacturer to remain competitive and sustainable, they must be able to manufacture at a low production cost with minimum resource consumption. One such approach to reduce manufacturing costs and take environmental issues into consideration could be the adoption of recycling and repurposing of waste paper. However, recent recycling research to address both environmental and economic challenges is predominately focused on the mechanical or electrical and electronics sectors. As the paper industry and consumers produce a large amount of waste paper, this lack of research highlights an important knowledge gap in the field of study. This article reviews the extent to which waste paper can be reused through recycling and repurposing. As a result, a cost modelling approach has been developed to predict cost fluctuations under different manufacturing constraints. The overall contributions of this research are: (i) identification of testing scenarios and parameters in waste paper; (ii) methods of recycling and repurposing cost modelling. A case study has been used to validate the method and based on the proposed approach, senior management of paper manufacturers could potentially achieve the best result to prevent unexpected costs and therefore maximise waste paper reuse.

DNA computer based algorithm is developed and evaluated for recyclable waste paper segregation.The concepts of replication and massive parallelism operations are used.The matching stage consists of Copy, Extract, Detect and Merge or Union operations.Gel electrophoresis operation is used to identify the candidate paper object grade.Success rate are 92% for WP, 90% for ONP and 93% for OCC with template size 5i?5. This article explores the application of DNA computing in recyclable waste paper sorting. The primary challenge in paper recycling is to obtain raw materials with the highest purity. In recycling, waste papers are segregated according to their various grades, and these are subjected to different recycling processes. Highly sorted paper streams facilitate high quality end products, while saving on processing chemicals and energy. In the industry, different sensors are used in paper sorting systems, namely, ultrasonic, lignin, gloss, stiffness, infra-red, mid-infra red, and color sensors. Different mechanical and optical paper sorting systems have been developed based on the different sensors. However, due to inadequate throughput and some major drawbacks related to mechanical paper sorting systems, the popularity of optical paper sorting systems has increased. The automated paper sorting systems offer significant advantages over the manual systems in terms of human fatigue, throughput, speed, and accuracy. This research has two objectives: (1) to use a web camera as an image sensor for the vision system in lieu of different sensors; and (2) to develop a new DNA computing algorithm based on the theme of template matching techniques for segregating recyclable waste papers according to paper grades. Using the concepts of replication and massive parallelism operations, the DNA computing algorithm can efficiently reduce the computational time of the template matching method. This is the main strength of the DNA computing algorithm in actual inspections. The algorithm is implemented by using a silicon-based computer to verify the success rate in paper grade identification.

Office waste paper constitutes a high-quality raw material for paper recycling industries; however, due to difficulties in the deinking process its exploitation is rather limited. The aim of the present study is the investigation of the impact of toner composition, printing processes and pulping conditions on the deinking of office waste paper through the flotation process. Deinking of papers printed by 21 different copiers and laser printers was tested under mild-conditions. It was attested that both the toner and the printing machine play an important role in the deinkability. The deinking efficiency varied significantly across different cases, spanning from low values ( 1,000 mm2 specks surface per m2 recycled paper surface). It was proved that the presence of styrene-acrylate copolymers and iron oxides in the toner resulted in reduced deinkability. In addition, slow printing speed had also a negative impact on the deinking efficiency. According to the research conducted, the removal of particles larger than 150 μm is a decisive factor in the deinking process. It was also demonstrated that the deinkability of office waste paper highly depends on the pulping conditions i.e. temperature, time and consistency. In particular, the highest deinkability was recorded when the three factors had simultaneously the highest values. Under these conditions, approximately 98% decrease in the total specks surface was achieved by flotation. The most important factor was the repulping consistency and the less important the temperature. More specifically, by increasing only the temperature, a reduction equal to 95.4% of specks surface was achieved, while by increasing only the consistency, 96.4% reduction of specks surface was achieved after the flotation process. In general, the intensity of repulping conditions resulted in decreasing toners’ specks size and therefore in increased deinking efficiency.

This paper proposes an agent-based simulation model to study and analyse the performance of various procurement and production policies in the recycled paper industry. The proposed model includes the recycled pulp production process, as well as the waste paper inventory and procurement processes. A detailed simulation model developed in partnership with a large recycled pulp producer in North America was developed in order to emulate the procurement manager's behaviour. Therefore, based on the observed behaviour of the procurement manager, a procurement behaviour model, which takes both market price and inventory requirement into account, is introduced. This paper also introduces a waste paper market model that simulates a market price and enables the control of price forecast accuracy. Two series of experiments were carried out in order to study the performance of procurement and production policies in several productions contexts. Results show that production Volume Flexibility has a negative impact on costs, inventory and quality. However, it is possible to partially reduce these issues with the introduction of contracts with Volume Flexibility, although only a limited effect has been observed in our experiments. A more significant strategy to improve costs consists in reducing production rate to the minimum level required to meet demand.

The use of Multi-criteria Decision Analysis (MCDA) was investigated in an exercise using a panel of local residents and stakeholders to assess the options for managing waste paper on the Isle of Wight. Seven recycling, recovery and disposal options were considered by the panel who evaluated each option against seven environmental, financial and social criteria. The panel preferred options where the waste was managed on the island with gasification and recycling achieving the highest scores. Exporting the waste to the English mainland for incineration or landfill proved to be the least preferred options. This research has demonstrated that MCDA is an effective way of involving community groups in waste management decision making.

The aim of the present study was to characterize the enzymatic deinking of various types of waste paper. Studies on the optimization of enzymatic deinking have been performed previously using commercially available enzyme preparations containing cellulase and hemicellulase. The enzymatic deinking of different types of waste paper demonstrated a high efficiency of 86.6% on laser-printed paper, but a low deinking efficiency of 12.9% was obtained with newspaper. All enzymatic treatments significantly improved the drainage rate of the deinked waste paper. Enzymatic deinking increased the tensile index of magazine paper but reduced the tensile index of bubble jet-printed paper, photocopy paper and newspaper. Enzymatic hydrolysis caused a 21.1% reduction in the tear index for bubble jet-printed paper, but a 3.1% increase in the tear index was obtained for laser-printed paper relative to respective blank. In addition, enzymatic hydrolysis increased the burst index by 4.7% relative to blank for laser-printed paper. However, photocopy paper showed the highest reduction (8.3%) in the burst index relative to blank. Taken together, these results suggest that enzymatic hydrolysis is both advantageous and detrimental to the mechanical properties of deinked paper. Thus, the proper regulation of enzymatic hydrolysis is crucial to improve the quality of recycled paper.

The possibility of changing waste paper sludge into valuable carbonaceous adsorbent was tested. The performance of three types of samples obtained from this waste was studied: chars (PK), activated chars (PKA) and activated initial material (PA). Pyrolysis of the initial material was carried out at 550, 600 and 700 °C, while the activation of the initial material and chars obtained with CO 2 at 550, 600 and 700 °C. The sorption capacity of carbonaceous adsorbents obtained was evaluated on the basis of NO 2 adsorption in dry and wet conditions. The NO 2 sorption properties of the activates decrease with increasing temperature of activation and the maximum sorption capacity was noted for the samples activated at 550 °C. On the basis of measurements in dry and wet conditions, the presence of water was found to increase the NO 2 breakthrough capacity. The NO 2 sorption capacity of the adsorbents obtained depended on the type and temperature of modification process and acid–base properties of the materials obtained.

Flotation is a critical process step for ink removal from recycled paper. Column flotation is a specific form of flotation that has grown in popularity recently. Extensive efforts during the past four decades to improve the flotation deinking operation sought an optimum blend of technological parameters, physico-chemical aspects and economical process conditions. With increasing demand to recover and recycle waste paper due to ecological and economical concerns, there is a need for an improved process and therefore for in-depth understanding of the mechanism and fundamental factors involved in the efficiency and economics of the deinking process. This paper reviews the progress made in the last decade (2000–2010) in deinking hydrodynamics, various measurement techniques, scale-up and design criterion.

We conducted an event study on the concealment of the blending ratio of waste paper with virgin pulp in Japan. By investigating 10 companies in the paper industry between May 30, 2007 and January 18, 2008, we clearly show that stock prices of the relevant companies were affected by the news on the concealment of the blending ratio of waste paper. In addition, the impact of the second event was found to be greater than that of the first event. Therefore, the concealment of major companies negatively affects the stock prices of non-major companies, which did not conceal information during this period. Thus, bad news is negatively assessed by the market, and this influence has spread in the paper industry in general.

The new version of a comprehensive simulation program of moving and fluidized-beds (CSFB or CSFMB) has been tested against data generated from a gasification unit at the University of California at Davis (UCD), Department of Biological and Agricultural Engineering. The pilot operated at atmospheric pressure under bubbling fluidized-bed and consumed various biomasses as well residues. Air was used as gasifying agent and electrical resistances around the reactor helped heating the reactor during start-up and were kept under low energy discharge during experiments. CSFMB was adapted to allow simulation of such cases as well to several other possibilities of additional heating systems to reactors. The present paper presents the results from cases of almond shells and walnut pruning gasification. Good to reasonable agreement between simulation and operational data have been obtained.

As an effective utilization of shochu distillation lees, which will soon be banned from dumping into the sea, we have succeeded in using these lees and waste newspaper to make Eco-friendly paper pots (hereafter called Eco paper pots). Further, by comparing the physical, mechanical, and chemical properties of Eco paper pots and those of waste paper pots (conventional pots), we found that the optimum condition for making Eco paper pots is to use a waste newspaper mixing ratio of 3%. We have also conducted a growth test of mini tomatoes in Eco paper and waste paper pots. We found that the Eco paper pots retained their shape without disintegration until the transplantation of the plants, with their pots, to the field. After transplantation, the plants’ roots penetrated through the Eco paper pot and radiated widely throughout the soil. Moreover, the Eco paper pots had a clear fertilizing effect.

The conventional office paper recycling process reduces used paper to a pulp prior to cleaning and re-forming. The difficulty of collecting and sorting waste paper, the low process yield and the energy required to re-form the used paper make this process economically unattractive and potentially environmentally less preferable than virgin production. Together these have resulted in a low recycling level for European office papers. An attractive alternative is the possibility of recycling office paper within the office, without destroying the mechanical structure of the paper. This paper reviews 104 patents filed mainly since the mid 1990s that propose technologies to achieve this. The patents are grouped into three categories: de-colouring the toner or ink; obscuring existing print; print removal by adhesion, ablation, abrasion or chemical processes. Some of these processes require new substrates, coatings, inks or toners, and to date only one has been released commercially. The various technology options are compared, and an assessment is offered of their likely future development.

A porcelain body traditionally used to produce ceramic art and design objects was re-formulated using additional waste paper. The aim of this study was to develop knowledge into the technological properties of paper-composite porcelain in its green state, for use within the traditional practices of ceramic art and design production. Characterisation was made by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Two different production methods used by potters, slip casting and free-hand pressing, were used. The presence of the paper fibre, the paper type and the content amount are the important factors in strengthening development. Significant differences were found in relation to the content amount of paper fibre, between the mother porcelain body and the different content amount of paper fibre in the paper-composite porcelain body.

This paper analyzes the spatial cost efficiency of the Swedish legislation regarding waste disposal handling. We focus on the case of corrugated board and recognize that the different counties in Sweden possess different economic prerequisites in terms of waste paper recovery and utilization potential. We employ data for six corrugated board mills and 20 counties and a non-linear programming model to identify the least cost strategy for reaching the politically specified recycling target of a 65% recovery rate for corrugated board. That is, the total costs of recovering a minimum of 65% in each county are calculated and compared with the case when the country as a whole recovers 65% of all old corrugated board is collected but there exist no uniform target for each county. The conclusion is that from an efficiency point of view the recovery efforts should be concentrated to the highly populated and urbanized counties, and not be uniformly divided throughout the country. In the base case, the results suggest that the cost efficient county-specific recovery rates should range from 51 to 72%.

The aim of this paper is to develop a model predicting the collected amount of waste paper at the regional level of municipalities. Learning about the factors that influence the amount of collected paper is a prerequisite for the evaluation and reorganization of collection systems. We hypothesize that the amount of collected paper depends on both the waste potential and the factors which influence the convenience such as the density of collection sites. For this study, we used a sample of 649 municipalities. Between the municipalities, the data show a high variance in terms of the collected waste paper per person and year. We developed a multivariate regression model providing valuable insights about the relationship between demographic parameters and the amount of collected waste paper. Furthermore, we found a significant positive impact of the convenience of the collection system.

This is in reference to our proposal for paper recycling plant. We have 25 year experience in waste paper industries, A Waste Paper Company is a family owned and operated company founded in 1988 by Eng. Sulaiman. The company pickup cardboard from local distribution warehouses around K.S.A which he then sold to recycling mills. As the years went by it continued adding to the list of materials to process and recycle, slowly building the single stream recycling facility we still operate today. Wadi Maramer Waste Paper company has grown to nearly 500 employees utilizing over 100 collections vehicles to service thousands of customers across K.S.A. We continue striving to provide quality customer service with a personalized touch at competitive prices.

This comment provides a critical analysis of Van Beukering and Bouman’s [World Development 29 (2001) 1717] article on global paper recycling and trade. We first question their notion that developin ...

Countries worldwide express waste paper recycling targets in terms of recovery and utilization rates. The main purpose of this paper is to identify and analyze the most important determinants of inter-country differences in these waste paper rates. By employing two regression models and using data for 89 and 81 countries, respectively, the paper concludes that relative waste paper recovery and use are largely market-determined, and depend thus on long-standing economic factors such as population intensity and competitiveness in the world market for paper and board products. We also find evidence that supports the conjecture that rich countries tend to recover relatively more waste paper than is the case in low-income countries, reflecting the higher demand for waste management and environmental policies in more developed economies. As recovery and utilization rates are determined largely by long-standing economic and demographic characteristics the degree of policy flexibility in affecting these rates may be limited. In particular, an ambitious utilization rate target may be very costly to enforce as it can conflict with existing trade patterns of paper and board products as well as with other environmental goals. Additional policy targets may, therefore, be desirable, especially since paper recycling is motivated primarily by environmental concerns and seldom is a benign activity in itself.

This paper identifies and estimates the relative impact that factor input prices, output market size and agglomeration effects have on the choice of location for investment projects in the European pulp and paper industry, with special focus on the price of wastepaper. A conditional logit model is developed to fit investment projects across 16 European countries for the period 1985–1995. The results suggest that factor input prices, in general, and the price for wastepaper, in particular, are neither a statistical nor an economic significant location determinant for a paper manufacturer. Furthermore, the results suggest that market size and agglomeration effects are considered more important than the price of raw material when an investment site is chosen.

In December 1998, the Borough of Fylde, UK, reduced the frequency of collection of their kerbside newspaper recycling scheme from once every 2 weeks to once every 4 weeks. The scheme incurred a drop of 8% in the overall tonnage collected, though over three quarters of this was recovered elsewhere through increased activity at the borough's paper bank sites. The overall drop-out rate from paper recycling was estimated to be

This is an expanded version of the Keynote lecture entitled “Innovations and Future Trends in Flotation Cell Design” delivered at Minerals Engineering '98. A category of flotation cell is discussed based on devices in the waste management industry. Seven examples of flotation cells utilized in waste paper deinking industry are reviewed to show the variety of approaches used to optimize the characteristics of a flotation system. In attempting to identify the key fundamental parameters, it is noted that comparisons of flotation effectiveness on the basis of bubble surface area flux (bsaf) often fail to reveal differences between flotation devices. This led to the conclusion that perhaps comparisons should be based on cost per delivered BSAF.

Paper passes through many hands. In the present paper, key parts of this cycle in Japan were examined, using questionnaire surveys of households and paper makers. The study aimed to examine the paper makers' strategy for paper production and their attitude to recycling, in comparison with those of the consumers. The study especially focused on toilet paper because consumers have a lot of freedom in purchasing toilet paper. A total of 1242 consumers and 60 paper makers responded. The major findings were as follows. First, we compared the criteria of consumers for purchasing toilet paper with the conjectures of paper makers. Brand, advertisements and the appearance of shopping displays received 60% support from paper makers, but less than 12% of consumers selected these criteria even if we exclude those who do not buy toilet paper or do not have any particular criteria. On the other hand, multiple plies and benefit to the earth were selected by moderate numbers (between 20 and 25%) of consumers, while only 16.77 and 5.69%, respectively of paper makers marked these criteria. Paper makers strongly believe that many retailers sell toilet paper as a loss-leader. By comparing those matters considered important for recycling by consumers with those considered important by makers, it was shown that many makers have a clear awareness of the particular problem, the lack of used paper consumption, in the current paper recycling situation in Japan.