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Some Properties of Composite Panels Made from Wood Flour and Recycled Polyethylene  [PDF]
Turgay Ozdemir,Fatih Mengeloglu
International Journal of Molecular Sciences , 2008, DOI: 10.3390/ijms9122559
Abstract: This study investigated the effect of board type (unmodified vs. MAPE modified) on the surface quality and thickness swelling-water absorption properties of recycled high density polyethylene (HDPE) based wood plastic composites. Additionally, two commercially available coatings (cellulosic coating and polyurethane lacquer coating) were also applied to composite surfaces and their adhesion strength, abrasion and scratch resistance, and gloss values were determined. This study showed that modification of the composites with MAPE coupling agent increased the surface smoothness and reduced the water absorption and thickness swelling of the panels. Abrasion resistance of the composites was also improved through MAPE modification. Regardless of board type, higher scratch resistance and gloss values were observed for polyurethane lacquer coated samples compared to those of cellulosic varnish coated ones. Improvement of adhesion strength was also seen on SEM micrographs.
Comparison Of Conventional And Recycled “Green” Office Paper
Klemen Mo?ina,Vera Rutar
Journal of Graphic Engineering and Design , 2011,
Abstract: To confront with the market need, we have to find alternative in respond to enormous necessity and application ofoffice paper. Therefore, one way in dealing with the problem is to replace or just decrease the use of paper madeentirely from primary components, mainly wood fibbers (deciduous and conifer). We analysed mechanical, optical,structural and microscopic properties. Experiments were performed on three conventional and three recycled officepapers reachable on the market. Results, obtained from measurements, confirm presumption, that mechanical andsurface properties of recycled office paper can be collated and they discern from conventional office paper.
K. Imandel,M. Abbaspoor,N. Moradi,F. Mokhtari
Iranian Journal of Public Health , 2000,
Abstract: In order to investigate the microbiological safety of sanitary tissues made of recycled scrap papers in Iran, random samples were taken for one year with the cooperation of the Iranian Standard and Industrial Research Institute (Karaj unit), of 44 types of sanitary tissues, two samples of each type including tissues, toilet papers and dippers as well as a control sample and their probable contamination with microbiological elements (bacterial & fungal) were assessed using proper ordinary and specific culture environments while also performing confirmation tests. Considering all aspects of this study including easy identification, high precision, simplicity of application, economic justification and observation of better results, the method which applies ringer 1/4 solution as the thinner environment was preferable to the saline peptone water solution. No contamination with Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeroginosa and E.coli bacteria was observed, but the excessive contamination with the mesophillic bacteria was confirmed. Among the 27 samples tested with the ringer 1/4 method, 8 cases (29.6%) were excessively contaminated with the mesophillic bacteria and one case (3.7%) with fungi. Meanwhile, out of the 43 samples that were tested with the saline peptone water solution, there was no excessive contamination with mesophillic bacteria and only one case (2.3%) of fungal contamination was observed.
Mathematical modeling of handmade recycled paper drying kinetics and sorption isotherms
Vieira, M. G. A.;Rocha, S. C. S.;
Brazilian Journal of Chemical Engineering , 2008, DOI: 10.1590/S0104-66322008000200009
Abstract: the objective of this work is to analyze and compare the natural and forced convective drying of handmade recycled paper. drying of recycled cellulose pulp was carried out under laboratory environment conditions and in a convective dryer with forced air circulation and controlled conditions of air temperature and velocity. the tests were conducted following a two-factor central composed factorial design of experiments, with six runs at the central point. the drying results were analyzed and fitted to mathematical models of fick, henderson and pabis (fick?s modified equation), page and he (considering the nonlinear fick effect). the model of page represented best the experimental data and the one of henderson and pabis resulted in an adequate fit for the paper drying kinetics. sorption isotherms were determined for the dried paper and the models of gab (guggenheim-anderson-de boer) and gdw (generalised d?arcy and watt) resulted in excellent fits of the experimental data. the water sorption mechanism was suggested by the analysis of the calculated parameters of the gdw model.
Wastewater treatment options for paper mills using recycled paper/imported pulps as raw materials: Bangladesh perspective  [cached]
Md. Mominur Rahman,Kazi Bayzid Kabir
Chemical Engineering Research Bulletin , 2010, DOI: 10.3329/cerb.v14i1.5236
Abstract: Paper sector in Bangladesh is currently expanding day-by-day to meet the increasing demand of industrial, writing/printing and specialty papers. Paper mills have adverse eects on the environment by producing huge quantity of wastewater. Yearly, approximately 14 million m3 wastewater is being discharged to the surface water bodies and irrigated lands without no/limited treatment. Water pollution from pulp and paper mills can be minimized through proper effuent characterization and design of appropriate treatment facilities. In this article dierent techniques of wastewater treatment for paper mills are discussed. Case study based on treatability analysis and jar test for a paper mill producing 200 m3/h of effuent is provided. On the basis of the case study a simplified treatment process is proposed. Proper treatment of such mills would not only save our environment but can also be beneficial for the industries by water usage minimization. Keywords: Pulp and paper mills; recycled paper; imported pulp; environmental impact; wastewater characterization; wastewater treatment DOI = 10.3329/cerb.v14i1.5236 Chemical Engineering Research Bulletin 14 (2010) 65-68
Green composites of thermoplastic corn starch and recycled paper cellulose fibers  [PDF]
Amnuay Wattanakornsiri,Katavut Pachana
Songklanakarin Journal of Science and Technology , 2011,
Abstract: Ecological concerns have resulted in a renewed interest in environmental-friendly composites issues for sustainabledevelopment as a biodegradable renewable resource. In this work we used cellulose fibers from recycled newspaper as reinforcementfor thermoplastic starch in order to improve its mechanical, thermal and water resistance properties. The compositeswere prepared from corn starch plasticized by glycerol (30% wt/wt of glycerol to starch) as matrix that was reinforcedwith micro-cellulose fibers, obtained from used newspaper, with fiber content ranging from 0 to 8% (wt/wt of fibers to matrix).Physical properties of composites were determined by mechanical tensile tests, differential scanning calorimetry, thermogravimetricanalysis, water absorption measurement and scanning electron microscopy. The results showed that higherfibers content raised the tensile strength and elastic modulus up to 175% and 292%, respectively, when compared to thenon-reinforced thermoplastic starch. The addition of the fibers improved the thermal resistance and decreased the waterabsorption up to 63%. Besides, scanning electron microscopy illustrated a good adhesion between matrix and fibers. Theseresults indicated that thermoplastic starch reinforced with recycled newspaper cellulose fibers could be fruitfully used ascommodity plastics being strong, cheap, abundant and recyclable.
Use of Poly-Lactic Acid (PLA) to Enhance Properties of Paper Based on Recycled Pulp  [PDF]
Klaus Doelle, Anh T. Le, Thomas E. Amidon, Biljana M. Bujanovic
Advances in Chemical Engineering and Science (ACES) , 2014, DOI: 10.4236/aces.2014.43038

Nowadays, recycled paper is broadly used due to environmental reasons. Furthermore, the addition of starch as a dry strength additive improves the properties of recycled paper. Poly-Lactic Acid (PLA), a product from bio-refinery process, has recently been shown to act as a promising strength additive that could be used in combination with starch to further improve the strength of paper. In this study, the use of PLA of three molecular weights (MW) in combination with four different starches was investigated. Three recycled pulps from different origins, with the kappa number of 27.9 to 66 were used. Paper handsheets were made, and selected paper properties were tested. The results indicate that handsheets properties were influenced by the MW of PLAs, the type of starch used, and the lignin content of the pulp. The paper handsheets made from lignin-rich pulp (pulp A, kappa number 66), combined with 0.1% medium MW PLA (PLA_1) and 0.9% cationic starch containing 0.43% N gave the highest improvement for tensile strength, wet tensile strength, air and water resistance. This result verifies that a higher kappa number pulp has better attraction to the hydrophobic PLA. Moreover, the higher charge cationic starch led to higher tensile strength due to the increase of affinity to the anionic fiber surface. Interestingly, results show that amphoteric starch is a promising substitute for high cationic charge starch when combined with the medium MW PLA to improve tensile strength of paper. This study demonstrated that a starch-PLA blend represents a promising approach in improving properties of recycled paper.

Treatment of Adsorbable Organic Halides from Recycled Paper Industry Wastewater using a GAC-SBBR Pilot Plant System
M.H. Muhamad,S.R.S. Abdullah,A.B. Mohamad,R.A. Rahman
Journal of Applied Sciences , 2011,
Abstract: Wastewater originating from recycled paper industry is known to be potentially toxic/inhibitory. Adsorbable Organic Halides (AOX) are among the toxic constituents generated from the recycled paper industry. The problems associated with AOX in the environment are their accumulation in the food chain and their persistence in nature. Hence, it is imperative to improve the effluent quality emanating from the recycled paper industry in order to meet the future discharge limits. One the plausible treatment technique is the use of the Sequencing Batch Biofilm Reactor (SBBR) with an option for Granular Activated Carbon (GAC) dosing. Pilot scale reactor based on combined physical-biological treatment of this GAC-SBBR system has been fabricated and evaluated for performance in the treatment of effluent from a recycled paper mill. The pilot GAC-SBBR was constructed in Muda Recycled Paper Mill located in Kajang, Selangor. It comprises of a High-density Polyethylene (HDPE) biofilm reactor with a diameter of 1.2 m, maximum water depth of 1.8 m and packed with 200 g L-1 of 2-3 mm granular activated carbon (coconut shells). The entire plant set-up was successfully commissioned. As a first step in the design procedure, a pilot test was run for a period of 2 months which include biomass acclimatization process for 1 month. Preliminary results showed that the GAC-SBBR could be an appropriate technology for the treatment of the wastewater. Based on reactor operation, the removal efficiencies of Pentachlorophenol (PCP) from the treated effluent was in the range between 82-100%, while the COD removal efficiency was between 39-81%. The initial results of pilot scale showed that the biofilm attached onto granular activated carbon can substantially remove the PCP recalcitrant in the wastewater. This research uses PCP as a model for AOX compound to study the adsorption and biodegradation of PCP in pilot plant biofilm reactor system.
Paulina Mocchiutti,María V. Galván,María C. Inalbon,Miguel A. Zanuttini
BioResources , 2011,
Abstract: Polyelectrolytes containing amine functional groups such as PAH (poly(allylamine hydrochloride)) can be useful, under certain conditions, for improving paper strength. In this work, the charge density of PAH was determined at different pH and ionic strengths; PAH adsorption onto the cellulosic fibers was characterized, and the effects of low PAH dosage on the papermaking properties were evaluated. It was found that the ionization of PAH is complete in acid media, but it is partial and depends on the ionic strength in neutral media. The adsorption isotherms of PAH on a recycled pulp from kraft liner allowed us to determine the amount needed to saturate the adsorption capacity of the fibers. For the three ionic strengths analyzed, the swelling of the fibers decreased when PAH was added in an amount corresponding to saturation (0.23% PAH on dried pulp). Nevertheless, the swelling was recovered when the amount of PAH was the double the saturation level (0.46% PAH on dried pulp). At these levels of addition, the papermaking properties were clearly improved, especially compressive strengths SCT (short compressive test) and CMT (concora medium test). The Page equation of tensile strength showed that PAH improved the shear bond strength, while the relative bonding area slightly decreased.
Concrete produced with recycled aggregates
Tenório, J. J. L.;Gomes, P. C. C.;Rodrigues, C. C.;Alencar, T. F. F. de;
Revista IBRACON de Estruturas e Materiais , 2012, DOI: 10.1590/S1983-41952012000500006
Abstract: this paper presents the analysis of the mechanical and durable properties of recycled aggregate concrete (rac) for using in concrete. the porosity of recycled coarse aggregates is known to influence the fresh and hardened concrete properties and these properties are related to the specific mass of the recycled coarse aggregates, which directly influences the mechanical properties of the concrete. the recycled aggregates were obtained from construction and demolition wastes (cdw), which were divided into recycled sand (fine) and coarse aggregates. besides this, a recycled coarse aggregate of a specific mass with a greater density was obtained by mixing the recycled aggregates of the cdw with the recycled aggregates of concrete wastes (cw). the concrete was produced in laboratory by combining three water-cement ratios, the ratios were used in agreement with nbr 6118 for structural concretes, with each recycled coarse aggregates and recycled sand or river sand, and the reference concrete was produced with natural aggregates. it was observed that recycled aggregates can be used in concrete with properties for structural concrete. in general, the use of recycled coarse aggregate in combination with recycled sand did not provide good results; but when the less porous was used, or the recycled coarse aggregate of a specific mass with a greater density, the properties of the concrete showed better results. some rac reached bigger strengths than the reference concrete.
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