Jewish National Fund (JNF) - Plant a tree in Israel Participate in the greening of the Holy Land right from your computer. Planting trees helps the environment by preventing soil erosion, attracting rain, pushing back the desert |
(Return to the top) |
Are bleaches used to whiten paper bad for the environment? |
There has been much concern about the waste products from bleaching processes used to make wood pulp white and free of impurities. The paper industry is now using less chlorine gas, the bleaching method that is worst for the environment. Bleaching with chlorine gas is not normally used in the recycling process. Elemental chlorine free (ECF) papers are papers made from pulp which has been bleached using oxygen, chlorine dioxide or other chemicals rather than pure chlorine. Totally chlorine free (TCF) papers are made from pulp which has been bleached without the use of any chlorine compounds at all. There is arguably little difference between ECF and TCF in the ** environmental impact of the pulp bleaching process, and both are significantly less polluting than traditional chlorine gas methods. From: http://www.greenchannel.com/puef
**COMMENT: THERE IS STILL POLLUTION AND WHAT ABOUT THE COST!?
By Ilana Teitelbaum July 01, 2007
From the moment we wake up in the morning and open a box of cereal to the hours we spend at work among printers, faxes, and copying machines, to times spent relaxing in the evening with a magazine or mass market paperback, we are constantly surrounded by paper.
Back in the late 1990s when email first began to take off, the dream of the "paperless office" seemed poised to make the leap from myth to reality. More than a decade later, it's become clear that this transition never took place, and today Americans consume about 187 billion pounds of paper each year. And that's just the US - all over the world, billions of trees are cut down annually in an attempt to keep pace with the world's growing demand for paper products.
A little-known alternative to trees for the production of paper is kenaf, a leafy, fast-growing annual related to the cotton plant. With a Persian name and ancient historical roots in Africa, the origin of kenaf is shrouded in mystery. One thing is certain: kenaf is both an effective and environmentally-friendly substitute to wood. Yet in spite of an endorsement from the US Department of Agriculture (USDA), kenaf has still not found its way into the mainstream market. High-end companies like Kodak, J.C. Penney and the Gap use kenaf paper for catalogues and film, but the vast majority of companies are still using wood-based paper.
Israeli Professor Roni Aloni of Tel Aviv University has been working with kenaf for 30 years, and may have finally discovered the breakthrough that will spring kenaf from obscurity. He, along with Professor Adi Avni and graduate student Jonathon Dayan, has succeeded at silencing a gene in the kenaf plant, which causes the kenaf to produce 50% more fibers per crop - and those fibers are longer and of higher quality than before. "The idea was to increase quality and fiber and stem length," Aloni told ISRAEL21c.
The technology is still in the testing stage, but the hope is that kenaf will replace trees as the source of pulp for paper manufacture. Kenaf grows much faster than trees, and would therefore be a more efficient source of pulp even without genetic modifications. "The same acreage of land planted with kenaf can yield the equivalent quantity of pulp fibers from wood that takes 20 years to grow," explained Aloni.
Aloni and Dayan have discovered a way to increase the levels of a hormone called gibellin in the kenaf plant - the hormone that is instrumental in producing the long, thick fibers that are used for making paper. Normally at a certain stage in the plant's growth, the production of gibellin is deactivated. Aloni and Dayan found the gene that causes the deactivation of the gibellin and then silenced the gene, so that the plant grows larger and more fibrous than before. "We found a gene and sequenced it with silencing technology. The scientific community did think about doing this, but they believed it would silence the whole system. We found a way to silence only one gene," explained Dayan.
Until now, kenaf paper has been slightly more expensive to produce than wood-based paper, particularly since the lumber industry in the US is subsidized by the government. According to Aloni, though, increasing the productivity of the kenaf plant will boost its value as a cash crop, creating an economic incentive for farmers. "Our technology makes... the kenaf able to compete economically with wood pulp for paper," he said.
The environmental benefits to replacing wood with kenaf would be significant. While wood paper mills are notorious for the deadly toxins they release into the atmosphere, kenaf requires fewer chemicals for processing because of its lower lignin content (the chemical that binds cellulose). Kenaf paper is also naturally brighter than wood paper, with the result that fewer chemicals are needed for the bleaching of kenaf paper. Chlorine, one of the most toxic offenders used for the bleaching of wood paper, is not used to bleach kenaf paper.
Forest officials in the US claim that cutting trees doesn't damage the environment because trees are a renewable resource. Unfortunately, re-planting trees doesn't save the natural habitats that were destroyed along with the original forests. Entire species of plants and animals have become extinct all over the world as a result of deforestation. Paper may not be made from animal skins anymore as it was in ancient times, but the current state of the industry probably kills far more species in the long run.
More than one company has expressed interest in Aloni's new development and is in negotiations with Ramot, the technology transfer company for Tel Aviv University. While Aloni is not at liberty to divulge the identities of these companies until the agreements are finalized, he was able to reveal that one company is in Italy while the other is in Brazil.
The Brazilian company, Aloni elaborated, plans on using kenaf for the dual purposes of paper and biofuel. "They would like to use the biggest kenaf plants mainly for energy. Kenaf fibers in the core are shorter and therefore less important for paper, while the outside layers of fiber are longer and excellent for paper-making. So we suggested they use the outside for paper and the core fibers to produce ethanol."
Meanwhile, the Italian company has requested "longer, softer fibers" for making paper and fabric for clothes, says Aloni, and adds, "Once we started to deal with companies we realized that each company needed something different. We have to grow 100 plants to produce one super-plant, and the more we do the more varieties of super-kenaf plants we get. We should be able to get different kinds that suit different needs."
Using an analogy, Aloni explains, "Every line of kenaf comes out differently - it's like a family: when you have children they may seem similar, but each one is different. We expect to get different lines and each might have different qualities.
"The paper and wood industry is more than $250 billion a year," concludes Aloni. "People think about cutting less wood, and when they do cut trees, then they would like to use it for wood products and not for paper. This is where kenaf could fit the bill."
|
|