The influence of screening process parameters on paper properties produced from wastepaper

The influence of screening process parameters on paper properties produced from wastepaper. Wastepaper processing is of pivotal importance for environmental protection; it is also crucial for the economy and the management of raw materials. Not only does recycling save space at landfills, it also saves an extremely valuable raw material used for paper production, i.e. wood. Unlike primary pulps, however, wastepaper contains much more than just cellulose fibres and fillers. The fact that recycled paper contains many contaminants, such as metal staples, paper clips, plastic film, glass fragments, and others, makes it necessary to develop a much more complex pulp preparation systems compared to the ones used for primary pulps. Contaminants affect not only the usable quality of paper made of wastepaper, but also cause the wear and tear of paper processing equipment. Thus, the purifying and screening of secondary pulps for further processing is very important. Considering the above, the authors’ objective was to study the impact of the width of screen slots on paper properties if produced from screened wastepaper pulp. Paper strength and paper surface properties were used as the main evaluation criteria. White and mixed wastepaper was used as research material. Based on the tests, the screen slot width was found not to have any significant impact on either paper mechanical strength or paper surface properties.

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WATER RESISTANCE OF RECYCLED PAPER PANEL

LANGKAU BETANG JURNAL ARSITEKTUR ◽

10.26418/lantang.v4i1.20392 ◽

2017 ◽

Vol 1 (1) ◽

pp. 23

Author(s):

Alexander Rani Suryandono ◽

Dimas Wihardyanto

Keyword(s):

Developing Countries ◽

Building Materials ◽

Information Sources ◽

High Technology ◽

Developed Countries ◽

Paper Strength ◽

Paper Recycling ◽

Recycled Paper ◽

Resistance Level ◽

The Impact

Recycled paper has many benefits, from saving woods to reducing carbon footprints. Industrialized recycled paper were mainly made in developed countries. These processes are using high technology and utilize chemical reactions and materials that can only be done in large factories. Meanwhile, paper are also used in developing countries. Newspaper is one of the mass medias that use a high number of paper. Printed newspaper are still used by the majority of people which they prefer rather than the digital newspaper version. This paper focuses in newspaper recycling that can be done in a home industry without high technology involved so that the people of developing countries could easily do it. The paper is broken into cellulose and then glued using tapioca starch. The recycled paper is formed as a panel for partition in a house. The recycled panel paper is put into the water to measure the resistance level. This experiment will help to understand the recycled panel paper strength against water. Recycling process in a home industry can be a part of green solution, especially in paper use. Through this experiment method research, it can be seen that recycled paper panel has a certain resistance level from water and may be used for partition panel. Keywords: recycled paper, panel, partition, environmental friendly, building materials KETAHANAN AIR PANEL KERTAS DAUR ULANGKertas daur ulang memiliki banyak manfaat, mulai dari mengurangi penggunaan kayu sampai karbon. Industri kertas daur ulang banyak terdapat di Negara maju. Proses ini membutuhkan teknologi tinggi dan menggunakan reaksi dan bahan kimia yang hanya mungkin dilakukan di pabrik besar. Sementara itu, kertas juga digunakan di Negara berkembang. Koran adalah satu dari media massa yang menggunakan banyak kertas. Koran cetak masih lebih banyak digunakan daripada media online. Paper ini membahas daur ulang kertas koran yang dapat dilakukan pada skala rumah tangga tanpa teknologu tinggi sehingga dapat dilakukan oleh orang awam di negara berkembang. Kertas koran dihancurkan menjadi selulosa dan menggunakan tepung tapioca sebagai perekat. Kertas daur ulang dibentuk menjadi panel untuk digunakan sebagai dinding partisi. Panel kertas daur ulang ini dimasukkan kedalam air untuk mengetahui ketahan terhadap air. Percobaan ini memperlihatkan tingkat ketahanan panel kertas daur ulang terhadap air. Proses daur ulang yang dapat dilakukan pada rumah tangga dapat menjadi bagian dari solusi hijau, khususnya pada penggunaan kertas. Melalui riset berbasis eksperimen ini, dapat dilihat bahwa panel kertas daur ulang memiliki ketahanan terhadap air dan dapat digunakan sebagai dinding partisi. Kata-kata kunci: kertas daur ulang, panel, partisi, ramah lingkungan, bahan bangunan REFERENCESAlice Wisler (2015) Facts about Recycling Paper. http://greenliving.lovetoknow.com/Facts_About_Recycling_Paper. Accessed 2 April 2016 Clay Miller (2011) 5 Benefits of Recycling Paper. http://www.ways2gogreenblog.com/2011/09/28/5-benefits-of-recycling-paper/. Accessed 10 May 2016 Hari Goyal (2015) Grades of Paper. http://www.paperonweb.com/grade.htm. Accessed 2 April 2016 Hari Goyal (2015) Properties of Paper. http://www.paperonweb.com/paperpro.htm. Accessed 2 April 2016 Kathryn Sukalich (2016) Everything You Need to Know about Paper Recycling. http://earth911.com/business-policy/business/paper-recycling-details-basics/. Accessed 15 July 2016 [U1] Larry West (2015) Why Recycle Paper. http://environment.about.com/od/recycling/a/The-Benefits-Of-Paper-Recycling-Why-Recycle-Paper.htm. Accesed 15 June 2016 Marie-Luise Blue (2008) The Advantages of Recycling Paper. http://education.seattlepi.com/advantages-recycling-paper-3440.html. Accessed 15 June 2016 Nina Spitzer (2009) http://www.sheknows.com/home-and-gardening/articles/810025/the-impact-of-disposable-coffee-cups-on-the-environment. Accessed 15 June 2016 Radio New Zealand (2010) Iwi not Giving Up Fight against Tasman Mill Discharges. http://www.radionz.co.nz/news/regional/64521/iwi-not-giving-up-fight-against-tasman-mill-discharges. Accessed 15 July 2016 Rick LeBlanc (2016) Paper Recycling Facts, Figures and Information Sources. https://www.thebalance.com/paper-recycling-facts-figures-and-information-sources-2877868?_ga=1.192832942.544061388.1477446686. Accesed 2 April 2016 Robinson Meyer (2016) Will More Newspapers Go Nonprofit? http://www.theatlantic.com/technology/archive/2016/01/newspapers-philadelphia-inquirer-daily-news-nonprofit-lol-taxes/423960/. Accessed 3 August 2016 School of Engineering at Darthmouth (2010) Forest and Paper Industry. http://engineering.dartmouth.edu/~d30345d/courses/engs171/Paper.pdf. Accessed 2 April 2016 T. Subramani, V. Angappan. (2015). Experimental Investigation of Papercrete Concrete. International Journal of Application or Innovation in Engineering and Management. Volume 4 Issue 5 page 134-143

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Application of Wavelet Filtering to Vibrational Signals from the Mining Screen for Spring Condition Monitoring

Minerals ◽

10.3390/min11101076 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1076

Author(s):

Natalia Duda-Mróz ◽

Sergii Anufriiev ◽

Paweł Stefaniak

Keyword(s):

Moving Average ◽

Diagnostic System ◽

Diagnostic Procedures ◽

Raw Material ◽

Main Task ◽

Screening Process ◽

Wavelet Filtering ◽

Vibration Data ◽

Main Challenge ◽

The Impact

The main task of mineral processing plants is to further process the raw material extracted in the mining faces into a concentrate with the highest possible concentration of the final product. In practice, it is a complex process in which several stages can be distinguished. After the ore has been transported to the surface by the skip shaft, one of the first steps is sieving the ore, which is typically performed using vibrating mining screens. In a typical Ore Enrichment Plant, the screening process is carried out by several such machines. This is a typical bottleneck in the technological chain. For this reason, the main challenge for users is to achieve the highest reliability and efficiency of these technical facilities. The solution is to focus on predictive maintenance strategies based on the development of monitoring and advanced diagnostic procedures capable of estimating the time of safe operation. This work was developed as part of an advanced diagnostic system ensuring comprehensive technical conditioning and early fault detection of components such as the engine, transmission, bearings, springs, and screen. This article focuses on vibration data. The problem of damage detection in the presence of periodically impulsive components resulting from falling feed material on the screen and its further screening process has been considered. These disturbances are of a non-Gaussian noise nature, the elimination of which is essential to extract the fault-related signal of interest. One solution may be to properly smooth and filter the raw signal. In this article, a wavelet filtering technique is applied. First, the wavelet filtering procedure is described. In the next step, the performance of a wavelet filter is investigated depending on its parameters. Then, the results of wavelet filtering are compared with such methods as low-pass filtering and smoothing using a moving average. Finally, the impact of wavelet filtering on the calculation of screen trajectories is investigated.

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Fractionation of epidermal cells from wheat straw pulp by flotation

TAPPI Journal ◽

10.32964/tj14.4.229 ◽

2015 ◽

Vol 14 (4) ◽

pp. 229-235

Author(s):

MIKKO KARJALAINEN ◽

ARI ÄMMÄLÄ ◽

PÄIVI ROUSU ◽

JOUKO NIINIMÄKI

Keyword(s):

Wheat Straw ◽

Cell Types ◽

Strength Properties ◽

Epidermal Cells ◽

Raw Material ◽

Paper Strength ◽

Paper Properties ◽

Vessel Elements ◽

Wide Availability ◽

Wheat Straw Pulp

The wide availability of wheat straw makes it a promising raw material for various fiber products, but its heterogeneity makes it a challenging material to use. In addition to reducing paper properties, some cell types cause processing problems such as silicate deposition and poor dewatering. The aims of this work were to examine the fractionation tendency of wheat straw pulp cells in flotation and to determine the effect of fractionation on paper strength properties. A cell type categorization based on automatic optical fiber analysis was used to assess fractionation. The results showed that epidermal cells can be selectively enriched from unbleached wheat straw pulp by flotation and other short cells had a tendency to become enriched in the overflow fraction. The underflow fraction consisted mostly of fibrous material, as well as vessel elements and long parenchyma cells. Removal of the epidermal cells from pulp will reduce its silicate content and improve the strength properties of the paper.

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Study on the Magnetic Separation Experiment of Vanadium and Titanium Iron Concentrate Pellets

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.549.969 ◽

2012 ◽

Vol 549 ◽

pp. 969-974

Author(s):

Lan Ma ◽

Shao Li Yang ◽

Ya Ling Li

Keyword(s):

Magnetic Separation ◽

Process Parameters ◽

Direct Reduction ◽

Reduction Process ◽

Separation Process ◽

Raw Material ◽

Iron Concentrate ◽

Metallized Pellets ◽

The Impact ◽

Alloy Iron

Based on Vanadium and Titanium iron concentrate pellets as raw material produced by direct reduction process of coal rotary hearth furnace in an enterprise, the paper studies the impact of magnetic separation process parameters on magnetic separation effect. The results shows that: the use of magnetic separation process can successfully separate metallized pellets, and obtain vanadium titanium micro-alloy iron powder and ti-enriched slag; suitable magnetic separation process parameters are: excitation current of 4A (magnetic field strength 2250Oe), particle size -200 mesh (-74μm), mine concentration of 1:3, iron recovery 92.5% TiO2 recovery up to 55.5%.

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Resource efficiency in deinked pulp production: a review

TAPPI Journal ◽

10.32964/tj13.11.37 ◽

2014 ◽

Vol 13 (11) ◽

pp. 37-43 ◽

Cited By ~ 4

Author(s):

LIISA KOTANEN ◽

MIKA KÖRKKÖ ◽

ARI ÄMMÄLÄ ◽

JOUKO NIINIMÄKI

Keyword(s):

Waste Disposal ◽

Resource Efficiency ◽

Raw Material ◽

Ecological Strategy ◽

Recycled Paper ◽

Paper Production ◽

Recycled Pulp ◽

Current State ◽

The Cost ◽

Pulp Production

The use of recovered paper as a raw material for paper production is by far the most economical and ecological strategy for the disposal of waste paper. However, paper production from recovered paper furnish generates a great amount of residues, and the higher the demand requirements for the end product, the higher the amount of rejected material. The reason for this is that the selectivity of the deinking process is limited; therefore, some valuable components are also lost in reject streams. The rejection of usable components affects the economics of recycled paper production. As the cost of waste disposal continues to increase, this issue is becoming more and more severe. This paper summarizes the current state of the resource efficiency in recycled pulp production and provides information on the volumes of rejected streams and the usable material within them. Various means to use these reject streams are also discussed, including the main findings of a recent thesis by the main author. This review summarizes current internal and external use of reject streams generated in the deinking operations.

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Does kraft hardwood and softwood pulp viscosity correlate to paper properties?

TAPPI Journal ◽

10.32964/tj15.10.643 ◽

2016 ◽

Vol 15 (10) ◽

pp. 643-651 ◽

Cited By ~ 1

Author(s):

ROBERT J. OGLESBY ◽

HUMPHREY J. MOYNIHAN ◽

RICARDO B. SANTOS ◽

ASHOK GHOSH ◽

PETER W. HART

Keyword(s):

Physical Properties ◽

Strength Loss ◽

Strength Properties ◽

Clear Correlation ◽

Paper Properties ◽

Physical Strength ◽

Pulp Viscosity ◽

Softwood Pulp ◽

The Impact ◽

Complex formation of modified chitosan and carboxymethyl cellulose and its effect on paper properties

TAPPI Journal ◽

10.32964/tj8.6.29 ◽

2009 ◽

Vol 8 (6) ◽

pp. 29-35 ◽

Cited By ~ 11

Author(s):

PEDRAM FATEHI ◽

LIYING QIAN ◽

RATTANA KITITERAKUN ◽

THIRASAK RIRKSOMBOON ◽

HUINING XIAO

Keyword(s):

Carboxymethyl Cellulose ◽

Polymer System ◽

Layer By Layer ◽

Paper Strength ◽

Anionic Polymer ◽

Paper Properties ◽

Modified Chitosan ◽

Layer By Layer Assembly ◽

Polyelectrolyte Titration ◽

Layer Assembly

The application of an oppositely charged dual polymer system is a promising approach to enhance paper strength. In this work, modified chitosan (MCN), a cationic polymer, and carboxymethyl cellulose (CMC), an anionic polymer, were used sequentially to improve paper strength. The adsorption of MCN on cellulose fibers was analyzed via polyelectrolyte titration. The formation of MCN/CMC complex in water and the deposition of this complex on silicon wafers were investigated by means of atomic force microscope and quasi-elastic light scattering techniques. The results showed that paper strength was enhanced slightly with a layer-by-layer assembly of the polymers. However, if the washing stage, which was required for layer-by-layer assembly, was eliminated, the MCN/CMC complex was deposited on fibers more efficiently, and the paper strength was improved more significantly. The significant improvement was attributed to the extra development of fiber bonding, confirmed further by scanning electron microscope observation of the bonding area of fibers treated with or without washing. However, the brightness of papers was somewhat decreased by the deposition of the complex on fibers. Higher paper strength also was achieved using rapid drying rather than air drying.

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The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽

10.3390/molecules26010149 ◽

2020 ◽

Vol 26 (1) ◽

pp. 149

Author(s):

Karol Leluk ◽

Stanisław Frąckowiak ◽

Joanna Ludwiczak ◽

Tomasz Rydzkowski ◽

Vijay Kumar Thakur

Keyword(s):

Polymer Composites ◽

Polylactic Acid ◽

Matrix Material ◽

Chemical Properties ◽

Precipitated Calcium Carbonate ◽

Cellulose Fibres ◽

Shape Factors ◽

Pure Cellulose ◽

Physico Chemical ◽

The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

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Estimating asymptomatic, undetected and total cases for the COVID-19 outbreak in Wuhan: a mathematical modeling study

BMC Infectious Diseases ◽

10.1186/s12879-021-06078-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xi Huo ◽

Jing Chen ◽

Shigui Ruan

Keyword(s):

Disease Transmission ◽

Large Scale ◽

Transmission Rate ◽

Control Strategies ◽

Herd Immunity ◽

Antibody Prevalence ◽

Screening Process ◽

Vaccination Programs ◽

Prevalence Level ◽

The Impact

Abstract Background The COVID-19 outbreak in Wuhan started in December 2019 and was under control by the end of March 2020 with a total of 50,006 confirmed cases by the implementation of a series of nonpharmaceutical interventions (NPIs) including unprecedented lockdown of the city. This study analyzes the complete outbreak data from Wuhan, assesses the impact of these public health interventions, and estimates the asymptomatic, undetected and total cases for the COVID-19 outbreak in Wuhan. Methods By taking different stages of the outbreak into account, we developed a time-dependent compartmental model to describe the dynamics of disease transmission and case detection and reporting. Model coefficients were parameterized by using the reported cases and following key events and escalated control strategies. Then the model was used to calibrate the complete outbreak data by using the Monte Carlo Markov Chain (MCMC) method. Finally we used the model to estimate asymptomatic and undetected cases and approximate the overall antibody prevalence level. Results We found that the transmission rate between Jan 24 and Feb 1, 2020, was twice as large as that before the lockdown on Jan 23 and 67.6% (95% CI [0.584,0.759]) of detectable infections occurred during this period. Based on the reported estimates that around 20% of infections were asymptomatic and their transmission ability was about 70% of symptomatic ones, we estimated that there were about 14,448 asymptomatic and undetected cases (95% CI [12,364,23,254]), which yields an estimate of a total of 64,454 infected cases (95% CI [62,370,73,260]), and the overall antibody prevalence level in the population of Wuhan was 0.745% (95% CI [0.693%,0.814%]) by March 31, 2020. Conclusions We conclude that the control of the COVID-19 outbreak in Wuhan was achieved via the enforcement of a combination of multiple NPIs: the lockdown on Jan 23, the stay-at-home order on Feb 2, the massive isolation of all symptomatic individuals via newly constructed special shelter hospitals on Feb 6, and the large scale screening process on Feb 18. Our results indicate that the population in Wuhan is far away from establishing herd immunity and provide insights for other affected countries and regions in designing control strategies and planing vaccination programs.

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Functionalization of Enzymatically Treated Apple Pomace from Juice Production by Extrusion Processing

Foods ◽

10.3390/foods10030485 ◽

2021 ◽

Vol 10 (3) ◽

pp. 485

Author(s):

Vera Schmid ◽

Antje Trabert ◽

Judith (Schäfer) Keller ◽

Mirko Bunzel ◽

Heike P. Karbstein ◽

...

Keyword(s):

Water Absorption ◽

Dietary Fiber ◽

Water Solubility ◽

Apple Pomace ◽

Raw Material ◽

Food Ingredients ◽

Insoluble Dietary Fiber ◽

Extrusion Processing ◽

The Impact ◽

Treated Apple

Food by-products can be used as natural and sustainable food ingredients. However, a modification is needed to improve the technofunctional properties according to the specific needs of designated applications. A lab-scale twin-screw extruder was used to process enzymatically treated apple pomace from commercial fruit juice production. To vary the range of the thermomechanical treatment, various screw speeds (200, 600, 1000 min−1), and screw configurations were applied to the raw material. Detailed chemical and functional analyses were performed to develop a comprehensive understanding of the impact of the extrusion processing on apple pomace composition and technofunctional properties as well as structures of individual polymers. Extrusion at moderate thermomechanical conditions increased the water absorption, swelling, and viscosity of the material. An increase in thermomechanical stress resulted in a higher water solubility index, but negatively affected the water absorption index, viscosity, and swelling. Scanning electron microscopy showed an extrusion-processing-related disruption of the cell wall. Dietary fiber analysis revealed an increase of soluble dietary fiber from 12.6 to 17.2 g/100 g dry matter at maximum thermo-mechanical treatment. Dietary fiber polysaccharide analysis demonstrated compositional changes, mainly in the insoluble dietary fiber fraction. In short, pectin polysaccharides seem to be susceptible to thermo-mechanical stress, especially arabinans as neutral side chains of rhamnogalacturonan I.

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