Paper is recycled into new paper through a process of mixing, breaking down, cleaning, and reforming the fibers. Here's a breakdown:
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Collection and Sorting: Used paper is collected and sorted by type (e.g., newspaper, office paper, cardboard).
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Pulping: The sorted paper is mixed with water and chemicals in a large container called a pulper. This process creates a slurry of fibers called pulp. The pulper acts like a giant blender, breaking down the paper into its constituent fibers.
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Screening and Cleaning: The pulp is then screened to remove contaminants such as tape, labels, staples, plastic, and glue. Larger contaminants are removed first, followed by smaller particles. Centrifugal cleaners are often used to separate heavier materials from the pulp.
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De-inking (Optional): For some types of recycled paper (especially printing and writing papers), the pulp is de-inked to remove inks, dyes, and coatings. This process often involves washing, flotation, or chemical treatments.
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Refining and Bleaching: The pulp may be refined to improve the strength and smoothness of the new paper. It can also be bleached to whiten the fibers, although unbleached recycled paper is also common and environmentally friendly.
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Paper Formation: The cleaned and refined pulp is then fed onto a large, moving screen. As the water drains away, the fibers interlock to form a continuous sheet of paper.
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Pressing and Drying: The newly formed paper sheet is pressed between rollers to remove more water and further compact the fibers. It then passes through a series of heated rollers to dry completely.
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Rolling: Finally, the dried paper is wound onto large rolls, ready to be cut and converted into new paper products.
In summary, the paper recycling process transforms used paper into a slurry, removes contaminants, and reforms the fibers into new paper.
