The technology to make paper by retting hemp was known to man nearly 2000 years back, and much until the 19th century books were printed from paper made from hemp. Paper making then was considered an art although it had more to do with biotechnology, but then biotechnology itself borders on art that in modern times has to do with genes and genetic modification.
Making paper from wood entails four different steps namely wood processing: pulping, bleaching and sheet formation, and today biotechnology plays a stellar role in some of these processes.
To understand how biotechnology plays a role in the making of paper, one has to have a basic understanding of the conventional steps involved in manufacturing paper.
Article Summary: "This article details how biotechnology has refined the process of manufacturing paper. Steps in wood processing include pulping, bleaching and sheet formation, and today biotechnology plays a stellar role in some of these processes. "
Conventional way of making paper pulp
At first the bark of the wood is removed and the logs so obtained are cut into smaller pieces called chips. The stripped bark is used as fuel for running the pulping mill power plant. The chips are heated under pressure along with caustic soda and sulfur so that lignin that binds the cellulose fibers are removed. This is called the chemical pulping process that gives 30% yield lesser than what is obtained by mechanical pulping.
Now the other way of pulping, that is, mechanical pulping process (gives more yield than chemical process) means forcing the debarked logs through rotating toothed steel discs that tear the logs and remove the lignin. Paper made this way has a brownish tinge because of the degradation of the lignin, as for example in the paper used for printing newspapers.
Let's now look at how biotechnology enhances the functionality of these processes.
Making pulp using enzymes
Fungi that can degrade lignin such as O. piliferum is used in a fermentation process before carrying out the normal mechanical or chemical pulping, so that it reduces the overall energy requirements when mechanical process is used or reduce the quantum of chemicals if chemical pulping is adopted.
Pulp bleaching using enzymes
Pulp is usually tinged with brown color due to lignin content and the conventional method has been to bleach pulp with chlorine to remove the color. Now there are two specific ways to enhance this bleaching process using enzymes. Xylase isolated from a fungus can successfully break down the carbohydrate xylan (this entraps pulp lignin). This can help reduce the need for chlorine in bleaching, but this does not solve the problem of chlorination such as the byproducts dioxins and PCBs. Therefore the re-engineered enzyme made by modification of three of the amino acid components of xylanase is used which is known as Biobrite® that helps in saving production costs and prevents formation of unwanted products during pulp bleaching process. Use of Biobrite® leads to substantial savings in chlorine which means lower chemical costs and reduction in toxic effluents as well.
The pulp bleaching process can also be augmented by using other enzymes such as laccase and manganese peroxidase
For further information log on website :
http://www.biotecharticles.com/Biotechnology-products-Article/Biotechnology-in-the-Manufacture-of-Paper-242.html
Making paper from wood entails four different steps namely wood processing: pulping, bleaching and sheet formation, and today biotechnology plays a stellar role in some of these processes.
To understand how biotechnology plays a role in the making of paper, one has to have a basic understanding of the conventional steps involved in manufacturing paper.
Article Summary: "This article details how biotechnology has refined the process of manufacturing paper. Steps in wood processing include pulping, bleaching and sheet formation, and today biotechnology plays a stellar role in some of these processes. "
Conventional way of making paper pulp
At first the bark of the wood is removed and the logs so obtained are cut into smaller pieces called chips. The stripped bark is used as fuel for running the pulping mill power plant. The chips are heated under pressure along with caustic soda and sulfur so that lignin that binds the cellulose fibers are removed. This is called the chemical pulping process that gives 30% yield lesser than what is obtained by mechanical pulping.
Now the other way of pulping, that is, mechanical pulping process (gives more yield than chemical process) means forcing the debarked logs through rotating toothed steel discs that tear the logs and remove the lignin. Paper made this way has a brownish tinge because of the degradation of the lignin, as for example in the paper used for printing newspapers.
Let's now look at how biotechnology enhances the functionality of these processes.
Making pulp using enzymes
Fungi that can degrade lignin such as O. piliferum is used in a fermentation process before carrying out the normal mechanical or chemical pulping, so that it reduces the overall energy requirements when mechanical process is used or reduce the quantum of chemicals if chemical pulping is adopted.
Pulp bleaching using enzymes
Pulp is usually tinged with brown color due to lignin content and the conventional method has been to bleach pulp with chlorine to remove the color. Now there are two specific ways to enhance this bleaching process using enzymes. Xylase isolated from a fungus can successfully break down the carbohydrate xylan (this entraps pulp lignin). This can help reduce the need for chlorine in bleaching, but this does not solve the problem of chlorination such as the byproducts dioxins and PCBs. Therefore the re-engineered enzyme made by modification of three of the amino acid components of xylanase is used which is known as Biobrite® that helps in saving production costs and prevents formation of unwanted products during pulp bleaching process. Use of Biobrite® leads to substantial savings in chlorine which means lower chemical costs and reduction in toxic effluents as well.
The pulp bleaching process can also be augmented by using other enzymes such as laccase and manganese peroxidase
For further information log on website :
http://www.biotecharticles.com/Biotechnology-products-Article/Biotechnology-in-the-Manufacture-of-Paper-242.html
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