Featured Research

from universities, journals, and other organizations

Economical and environmentally-friendly pulp bleaching

Date:
March 11, 2011
Source:
Aalto University
Summary:
A simulation model for pulp bleaching has been created. The model will yield information of phenomena taking place during pulp bleaching, especially about reactions between lignin and bleaching chemicals that cause the pulp's brown color. The chemicals used in pulp bleaching are costly. In addition, water and energy are used in the bleaching process. With the help of the knowledge produced by the new model, pulp can be bleached more economically and in a more environmentally friendly way.

A simulation model for pulp bleaching was created in the Virtual Pulp Bleaching (VIP) project led by Professor Tapani Vuorinen from the Aalto University School of Chemical Technology. The model will yield information of phenomena taking place during pulp bleaching, especially about reactions between lignin and bleaching chemicals that cause the pulp's brown colour. The chemicals used in pulp bleaching are costly. In addition, water and energy are used in the bleaching process. With the help of the knowledge produced by the VIP model, pulp can be bleached more economically and in a more environmentally friendly way.

Related Articles


The VIP model developed includes a library of chemical reactions for most commonly used bleaching chemicals. The models of the chemical reactions and other phenomena which participate in the bleaching process function as a part of process equipment models with the combination of which it is possible to construct flow diagrams used in the bleaching process at the plant. In addition, the model can be used to simulate experimental arrangements at the laboratory scale.

The simulation model will be used in research and teaching, especially at Aalto University. In industry, the model can be used for planning of the bleaching process, training of personnel, as well as optimization of the existing processes.

Bleaching is the process used after pulping to remove lignin residual

Cellulose is one of the raw materials of paper and cardboard, which is obtained from wood pulping process. Pulping takes place in a high temperature with the help of chemicals; lignin that glues the wood fibres together partially dissolves and the fibres separate from each other. After the pulping process is over, the cellulose is bleached aiming to remove the rest of the lignin, the so-called residual lignin, with different chemicals. Lignin removal is important because lignin gives the fibres their brown colour. Pulps pronounced brightness is important in the production of fine grade paper.

Lignin polymer consists of different chemical groups, which differ from each other in their reactivity with different bleaching chemicals and, for example, in the extent they affect the colour of the fibre. For the construction of the VIP model, attention was directed to these types of different chemical groups to allow the model to provide a sufficiently realistic picture of the effect of different conditions, such as those due to temperature and chemical doses, on the success of bleaching.

The project was multidisciplinary: it drew together scientists from the fields of wood chemistry and the modelling of chemical processes as well as experts from the pulping industry. This kind of cooperation was necessary to obtain a useful model.

The Virtual Pulp Bleaching project is one of the awarded projects of the Forestcluster's EffTech program. The five-year Intelligent and resource efficient production technologies (EffTech) program started in 2008, and its total budget is € 40 million. The VIP project includes Aalto University, VTT Technical Research Centre of Finland and the Lappeenranta University of Technology.


Story Source:

The above story is based on materials provided by Aalto University. Note: Materials may be edited for content and length.


Cite This Page:

Aalto University. "Economical and environmentally-friendly pulp bleaching." ScienceDaily. ScienceDaily, 11 March 2011. <www.sciencedaily.com/releases/2011/03/110311131847.htm>.
Aalto University. (2011, March 11). Economical and environmentally-friendly pulp bleaching. ScienceDaily. Retrieved March 4, 2015 from www.sciencedaily.com/releases/2011/03/110311131847.htm
Aalto University. "Economical and environmentally-friendly pulp bleaching." ScienceDaily. www.sciencedaily.com/releases/2011/03/110311131847.htm (accessed March 4, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Wednesday, March 4, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Tourists Visit Rare Grey Whales in Mexico

Raw: Tourists Visit Rare Grey Whales in Mexico

AP (Mar. 4, 2015) Once nearly extinct, grey whales now migrate in their thousands to Mexico&apos;s Vizcaino reserve in Baja California, in search of warmer waters to mate and give birth. Tourists flock to the reserve to see the whales, measuring up to 49 feet long. (March 4) Video provided by AP
Powered by NewsLook.com
Raw: Injured Miners Treated After Blast

Raw: Injured Miners Treated After Blast

AP (Mar. 4, 2015) An explosion ripped through a coal mine before dawn Wednesday in war-torn eastern Ukraine, killing at least one miner, officials said. Graphic video of injured miners being treated in a Donetsk hospital. (March 4) Video provided by AP
Powered by NewsLook.com
Australian Museum Shares Terrifying Goblin Shark With the World

Australian Museum Shares Terrifying Goblin Shark With the World

Buzz60 (Mar. 4, 2015) The Australian Museum has taken in its fourth-ever goblin shark, a rare fish with an electricity-sensing snout and &apos;alien-like&apos; jaw. Mike Janela (@mikejanela) takes a look. Video provided by Buzz60
Powered by NewsLook.com
Mount Everest Has a Poop Problem

Mount Everest Has a Poop Problem

Buzz60 (Mar. 4, 2015) With no bathrooms to use, climbers of Mount Everest have been leaving human waste on the mountain for years, and it&apos;s becoming a health issue. Mike Janela (@mikejanela) has more. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins