October 30, 2008

The Seven Cycles of Recycled Paper

. October 30, 2008

Here is a great, user-friendly article from Earth911 about how paper is recycled.

Paper, it is said, can be recycled up to seven times. Taken with the fact that recycled paper is also cheaper and easier to convert to pulp than wood, it makes an ideal candidate for collection and reuse. But what exactly are these seven cycles, and what happens to paper after this point? In order to answer these questions, we need to examine the paper-making process more closely.

Learning Curve: Definitions & Grades

First, it’s important to know that “recycled” can mean many different things. For example, paper companies used to consider mill scraps from lumber cuttings recycled content. The key phrase to identify is post-consumer. This refers to content that comes from used paper products.
Second, you should know that when it comes to paper, grades count. There are five main grades of paper according to the EPA, but you’re most likely to find these four in your home or workplace.

• Newspaper: Not the same as magazines or catalogs. Only newspapers fall into this category
• Office paper: Generally high-grade white printer and copier paper, envelopes and letterhead.
• Corrugated containers: These include boxes of all kinds, from shipping to food and shoe boxes
• Mixed paper: This category is a catch-all for the other types of paper, such as phone books, magazines, junk-mail or colored papers

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While lower grade paper, such as a cereal box, can be turned into another cereal box, it cannot be recycled into a shiny piece of office paper; however, if office paper is kept separate from low-grade papers, then it can be turned back into office paper. For this reason, sorted paper gives companies more versatility in what they can produce.

Once sorted, the paper is broken down in much the same way, regardless of type. Batches are soaked in a water and chemical bath in order to break them down into “pulp,” the small fibers that make paper. Next, the pulp undergoes several stages of cleaning in order to remove contaminants like glue, plastic, staples, and finally, ink. Once paper is re-bleached, if necessary, it is ready to be mixed with virgin fibers and made into paper once more. At this final stage, recycled pulp is no different from virgin pulp. So why only seven cycles?

And The Answer Is…

The answer boils down to size. Each time wood fibers are reprocessed (chopped, heated, pressed) they break down a bit. After about five to seven cycles, the pulp bits are so small that they simply slip through the filtering screens and end up in the wastewater. In this manner, the quality of recycled paper is not affected by pulp that is no longer useful.
Most products today, especially corrugated containers, contain recycled post-consumer content, but consumer demand, more than federal or industry standards, is what drives paper companies to increase recycled percentages. When it comes to paper (all kinds), purchasing or requesting recycled goods maintains a steady demand for this product.

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