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FEU Download Handbook of Pulping and Papermaking Free PDF Book
Download the book Handbook of Pulping and Papermaking in PDF and EPUB format. Here you can download all books for free in PDF or Epub format. Use the button available on this page to download or read a book online. Download Free PDF. Download Free PDF. handbook of paper and board. Ahmed Ashour. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 30 Full PDFs related to this paper. READ PAPER. handbook of paper and board. Download. handbook of paper and board. Handbook of Pulping and Papermaking Download As PDF: Handbook of Pulping and Papermaking. Detail books: Author: Date: Page: Rating: Reviews: 4 Category: Book. Reads or Downloads Handbook of Pulping and Papermaking Now. Handbook of Pulping and Papermaking PDF.
Handbook of pulping and papermaking free download
To browse Academia. Skip to main content. Log In Sign Up. Download Free PDF. Ahmed Ashour. Download PDF. A short summary of this paper. The Egyptians, Greeks and Romans wrote on "papyrus", a paper-like material. Today's kind of paper was first developed and used in China.
Paper was the most important carrier of information in the past. It was only with increasing paper production that the transfer of knowledge, education and information to a larger portion of society became possible. With paper emperors were able to administrate large empires more easily. In former times paper was a valuable product, and paper making an art -an art that was often kept secret because of the outstanding advantages of the product. Today paper has changed from a rare artisan material to a commodity product, with a high practical value in communication, in educational, artistic, hygienic, sanitary, and technical applications.
Nobody can imagine a world without paper. A large variety of paper grades are produced to suit the special requirements of each application: Graphic paper grades, packaging papers and board, hygienic papers, handbook of pulping and papermaking free download, and speciality paper grades. Paper can be impregnated, coated, handbook of pulping and papermaking free download, laminated, creped, molded etc.
Paper products embellish our homes, handbook of pulping and papermaking free download sanitary products made of paper ease our daily life, handbook of pulping and papermaking free download. An easier life is also more likely with a sufficient number of banknotes in the briefcase. Packaging papers and board grades support supermarket logistics and product presentations.
Computer print-outs and other graphic papers such as newspapers, magazines and books accompany us through our life. Even today in our digital world paper is a reliable means of long-time handbook of pulping and papermaking free download and data preservation. The worldwide consumption of paper is increasing steadily over the years. The paper consumption in individual countries is related to their gross national product and hence the further increase in paper and board consumption will be different in different countries depending on whether economic saturation, as e.
The ratio of the worldwide consumption of the different paper and board grades has changed in the past and will change in the future according to technical and social evolution and developments in the individual countries and in the world as a whole.
The components used in paper and board production worldwide are given in Fig. Today recovered paper has become the main resource for paper and board production, followed by chemical pulp, mechanical pulp, pigments and fillers, and chemical additives. Paper is mainly based on fibers from cultured woods, and is a renewable and recyclable raw material. The special characteristic of this fiber material is that the paper strength results from the hydrogen bonding between the individual fibers.
In certain cases it is enhanced by the addition of starch or wet strength additives. The hydrogen bonds are loosened by rewetting the paper which allows easy recycling. Increased paper recycling and sustained foresting help to preserve the wood resources of the earth. The paper industry has steadily improved its standards in complying with environmental demands as related to water consumption and water effluents, energy consumption, and primary and secondary fiber consumption.
These standards have to be maintained and even improved in the future because of further increasing paper and board consumption and limited resources.
It seems that this concentration process has not yet come to an end. Papermaking has changed from an "art", where all specific processes were kept secret, to an industry with high-tech production facilities and with a scientific approach. Great challenges are e. Only high quality products -at low price -satisfy the expectations of the customer and end user. Since paper is a commodity, low cost production is mandatory. As the fiber raw material is handbook of pulping and papermaking free download main cost factor in paper production recovered paper has become the main fiber stock material worldwide and its proportion will increase further.
Several grades, such as newsprint and many packaging and board grades, can be entirely based on recycled fibers. Today recovered fibers must be used in paper grades similar to the recovered paper grade, downgrading of recovered paper high quality fibers for lower quality paper products is no longer economic.
In former times, with mainly virgin fibers consumption, a paper mill was located close to the wood and the water and energy resources.
This is still true for regions of Portugal, Spain and Brazil with Eucalypt plantations used mainly for copy or similar paper grades. One result of the increased use of recovered paper is that certain new "green field" paper mills are established today in the vicinity of highly populated areas to have easier access to recovered paper resources and to be closer to the market. This drop is mainly due to increased machine speeds and machine widths as well as to improved runnability.
On the other hand the investment costs related to annual turnover have remained constant or even increased. Overview of the Manufacturing Process for Paper and BoardPapermaking today includes, in principle, the same process steps as applied for centuries: preparation of the fiber material, sheet or web forming, pressing, drying, handbook of pulping and papermaking free download, sizing and smoothing.
However, in the last two centuries much of the detail has changed. Each process step has undergone -and still undergoes today -intensive research and development work to meet economic and ecological requirements. All links in the chain between fiber and end user contribute to this progress.
The chain does not only include the paper producing industry itself and its suppliers such as the machine and chemical industry, but also the paper industry's customers and related industries, e. The papermaking process Fig. All these components have to be adequately prepared for optimum use in the papermaking process steps.
The additives may be delivered ready for use or may have to be finally prepared according to the requirements in the mill. Fiber stock preparation includes several unit operations depending on the furnish and the purpose. Stock preparation of virgin fiber pulp needs less machinery and energy than the preparation of recovered paper which, however, is the cheaper raw material.
Fiber stock preparation ends handbook of pulping and papermaking free download the paper machine chest. Here stock of high consistency is preferred to minimize carry-over of chemicals and contaminants. Stock preparation is followed by the approach flow system connecting stock preparation with the paper machine. The approach flow system ends at the distributor of the headbox. The task of the paper machine is to produce paper or board of the quality required by the end user -or by the intermediate process steps such as converting or printing.
The paper and board properties have to be uniform in machine direction MD as well as in cross machine direction CD. Further, the paper machine has to make the best use of the quality potential of the entering stock.
The paper manufacturing process ends with the paper web being reeled at the reeler at full width. By tradition and technical feasibility, coating and supercalendering for surface quality improvement have been off-line processes. Today both are increasingly integrated into the paper machine.
The final activities in paper and board production are slitting of the full width reels into smaller rolls at the winder followed by packaging the rolls for shipment.
Paper broken during the manufacturing process has to be recycled and fibers are recovered from the white water of the paper machine in a saveall. White water is fed back from the paper machine to the approach flow system and stock preparation. Fresh water is supplied to the paper machine. Along the paper production line stock consistency varies according to the requirements of the unit operations.
Unfortunately the terms low, medium and high consistency relate to different consistency numbers depending on the actual unit operation Table 1. It is also important to note whether the number gives the overall consistency including fibers and fillers or just fibers.
Tschudin IntroductionPaper is defined internationally as a thin layer of mostly cellulosic plant fibers, produced on a screen by dewatering a slurry of fibers in water [2]. The slurry is called pulp. Despite recent developments proteinic or synthetic fibers, chemical additives, coating, etc. Precursors of Paper Tapa Bark-cloth Bark-cloth, made since prehistoric times, is found widely along the Equator belt in nearly all cultures, used mainly for decorating and clothing [3].
It is produced by beating or pressing the inner bark liber, bast of trees and shrubs like paper mulberry, lime-tree, fig or daphne, and is known by the generic term "tapa", derived from the Polynesian language.
Tapa is a felt-like material, similar to thick woven paper, showing in most cases traces of the beating mallets. Technically speaking, it is a kind of non-woven handbook of pulping and papermaking free download. There are three different techniques to be observed in tapa-making. The most sophisticated method consists of three steps. In the first, small strips of bast are cut and cooked for several hours in suds of wood ash.
This cooking is very similar to the basic operation of our alkaline pulping. Then the strips are rinsed, placed together on a wooden board and handbook of pulping and papermaking free download with a mallet, thus forming a small sheet on the board. The third step consists of drying and smoothing. FeltFelting techniques go back into prehistory [4].
Plant fibers or animal hair are separated from their original linking as much as possible and spread in thick layers onto a cloth or mat. Then they are covered by another cloth and beaten by foot stamping or with heavy wooden sticks to entangle them and stick them together. In another way, handbook of pulping and papermaking free download, the ground mat bearing the fibers is rolled and the roll is beaten.
The mat is unrolled and rolled again several times. In wet felting, water is used to soak the fibers and help felting. PapyrusPapyrus, the most commonly used writing material handbook of pulping and papermaking free download Ancient Egypt and Classical Antiquity, was made in Egypt from the beginning of the 3rd millennium BC.
The triangulated stem of the papyrus plant is peeled and the pith cut into thin, small strips. A first layer of wet strips placed vertically side by side with a slight overlap is laid onto a board. Then, a similar layer of horizontally oriented stripes is laid above it. Beating with wooden sticks and pressing the still wet layers leads to a sheet of entangled fibers, most remaining in the original linking of the pith. After drying and smoothing several sheets are glued together to form a roll, ready to be written on.
Gary A Smook - Paper Industry International Hall of Fame
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Download Handbook of Pulping and Papermaking PDF Ebook online Book title: Handbook of Pulping and Papermaking. Download the book Handbook of Pulping and Papermaking in PDF and EPUB format. Here you can download all books for free in PDF or Epub format. Use the button available on this page to download or read a book online. Handbook of Pulping and Papermaking Download As PDF: Handbook of Pulping and Papermaking. Detail books: Author: Date: Page: Rating: Reviews: 4 Category: Book. Reads or Downloads Handbook of Pulping and Papermaking Now. Handbook of Pulping and Papermaking PDF. Download Free PDF. Download Free PDF. handbook of paper and board. Ahmed Ashour. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 30 Full PDFs related to this paper. READ PAPER. handbook of paper and board. Download. handbook of paper and board.
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