Pulping processes
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Pulping processes

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Published by Interscience Publishers in New York .
Written in English

Subjects:

  • Wood-pulp,
  • Wood -- Chemistry

Book details:

Edition Notes

StatementSven A. Rydholm
The Physical Object
Paginationix, 1269 p. :
Number of Pages1269
ID Numbers
Open LibraryOL14657338M

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Alongside the traditional aspects of pulping and papermaking processes, this book also focuses on biotechnological methods, which is the distinguishing feature of this book. It includes wood-based products and chemicals, production of dissolving pulp, hexenuronic acid removal, alternative chemical recovery processes, forest products biorefinery. Pulping a book is stripping a book of its cover and having the torn book pulped and recycled in the plant. The severed cover is sent back to the publishing house as evidence that the book has been destroyed or discarded or recycled into paper or cardboard products. mechanical process, semi chemical process, alkaline chemical process, sulfite process, etc. Physical strength properties of paper depend on the quality of raw material, its pulping, bleaching and subsequent paper making processes. Technology has made it easy to process these raw materials in an economic and lucrative way to meet the global demand. The 4 processes principally used in chemical pulping are kraft, sulfite, neutral sulfite semichemical (NSSC), and soda. The first 3 display the greatest potential for causing air pollution. The kraft process alone accounts for over 80 percent of the chemical pulp produced in the United Size: KB.

pulping processes. If roundwood is used, it is first debarked, usually by tumbling in large steel drums where wash water may be applied. The debarked wood bolts are then chipped in a chipper if the pulping process calls for chemical digestion or are fed into a grinder in the. Types of Pulping Processes. Types of Pulping Processes. Pulp can be divided into two principal types: mechanical or chemical pulp. In fact there are more than two types of pulp. Pulp from recovered paper poses a different challenge for the papermaker as it often has to be de-inked and other contaminants removed. and sodium sulphide (Na2S) to pulp wood, is the dominant pulping process in the pulp and paper industry. About million tons/year of kraft pulp are produced globally, accounting for two-thirds of the world’s virgin pulp production and for over 90% of chemical pulp. The high strength of kraft pulp, the ability of the process to handle. The kraft process (also known as kraft pulping or sulfate process) is a process for conversion of wood into wood pulp, which consists of almost pure cellulose fibers, the main component of paper. The kraft process entails treatment of wood chips with a hot mixture of water, sodium hydroxide (NaOH).

The process for making this type of molded pulp is similar to plain molding as discussed in the previous section. The second type of molded pulp is slightly thinner ranging from 1/8 to 3/16 inch thick (, [4]). It is called “Transfer Molding” and is similar toFile Size: KB. The kraft chemical recovery process is a mature, effective technology that provides for recycling of the pulping chemicals, efficient generation of steam and electrical power from the fuel value. Pulp and Paper Pulp is the fibrous mass that results when a pulping process ruptures the bonds in the wood structure that hold the woody cells together. Pulping is done mechanically, thermomechanically, chemically, or with combinations of these treatments. Commercial processes are generally classified as mechanical, chemical, or semi-. The kraft process is the dominating pulping process, which accounts for almost 60% of all mechanical and chemical pulp produced worldwide. In this process, pulp is produced by digesting wood chips at high temperature and pressure in a sodium hydroxide solution called white liquor to dissolve the wood lignin and other organic wood substances and to liberate the wood fibers that form the pulp .