Paper

Paper recycling is the process of recovering waste paper and remaking it into new paper products. There are three categories of paper that can be used as feedstocks for making recycled paper: mill broke, pre-consumer waste, and post-consumer waste.
Mill broke is paper trimmings and other paper scrap from the manufacture of paper, and is recycled internally in a paper mill.
Pre-consumer waste is material that was discarded before it was ready for consumer use.
Post-consumer waste is material discarded after consumer use, including OM (old magazines), OTD (old telephone directories), and RMP (residential mixed paper).

Paper suitable for recycling is called "scrap paper".

While there are differences depending on the specific type of paper being recycled (corrugated fiberboard, newspaper, mixed office waste), recycling processes include the following steps:

1. Pulping: Adding water and applying mechanical action to separate fibers from each other.
2. Screening: Using screens, with either slots or holes, to remove contaminants that are larger than pulp fibers.
3. Centrifugal cleaning: Spinning the pulp slurry in a cleaner causes materials that are denser than pulp fibers to move outward and be rejected.
4. Flotation: also called deinking. Passing air bubbles through the pulp slurry, with a surfactant present, causes ink particles to collect with the foam on the surface. By removing contaminated foam, pulp is made brighter.
5. Kneading or dispersion: Mechanical action is applied to fragment contaminant particles.
6. Washing: Small particles are removed by passing water through the pulp.
7. Bleaching: If white paper is desired, bleaching uses peroxides or hydrosulfites to remove color from the pulp.
8. Papermaking: The clean (and/or bleached) fiber is made into a new paper product in the same way that virgin paper is made.
9. Dissolved air flotation: Process water is cleaned for reuse.
10. Waste disposal: The unusable material left over, mainly ink, plastics, filler and short fibers, is called sludge. The sludge is buried in a landfill, burned to create energy at the paper mill or used as a fertilizer by local farmers.

Why recycle paper?
Industrialized paper making has an effect on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).Recycling paper reduces this impact.

Today, 90% of paper pulp is made of wood. Paper production accounts for about 35% of felled trees,and represents 1.2% of the world's total economic output. Recycling of newsprint saves about 1 tonne of wood while recycling 1 tonne (1.1 ton) of printing or copier paper saves slightly more than 2 tonnes of wood. This is because kraft pulping requires twice as much wood since it removes lignin to produce higher quality fibers than mechanical pulping processes. Relating tonnes of paper recycled to the number of trees not cut is meaningless, since tree size varies tremendously and is the major factor in how much paper can be made from how many trees. Trees raised specifically for pulp production account for 16% of world pulp production, old growth forests 9% and second- and third- and more generation forests account for the balance. Most pulp mill operators practice reforestation to ensure a continuing supply of trees[citation needed]. The Forest Stewardship Council (FSC) certifies paper made from trees harvested according to guidelines meant to ensure good forestry practices. It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (80,000 km²) of forestland.

Energy consumption is reduced by recycling, although there is debate concerning the actual energy savings realized. The EIA claims a 40% reduction in energy when paper is recycled versus paper made with unrecycled pulp. while the Bureau of International Recycling, BIR, claims a 64% reduction. Some calculations show that recycling one ton of newspaper saves about 4,000 KWh of electricity, although this may be too high (see comments below on unrecycled pulp).

About 35% of municipal solid waste (before recycling) by weight is paper and paper products. Recycling 1 tonne of newspaper eliminates 3 cubic meters of landfill. Incineration of waste paper is usually preferable to landfilling since useful energy is generated. Organic materials, including paper, decompose in landfills, albeit sometimes slowly, releasing methane, a potent greenhouse gas.

Modern mills produce considerably less pollution than those of a few decades ago. Recycling paper decreases the demand for virgin pulp and thus reduces the overall amount of air and water pollution associated with paper manufacture. Recycled pulp can be bleached with the same chemicals used to bleach virgin pulp, but hydrogen peroxide and sodium hydrosulfite are the most common bleaching agents. Recycled pulp, or paper made from it, is known as PCF (process chlorine free) if no chlorine-containing compounds were used in the recycling process. However it should be noted that recycling mills may have polluting by-products, such as sludge.
(Courtesy Wikipedia)

Companies in Trinidad who recycle paper are:

• Ace Recycling Limited - 638-3946, 675-1805.
• SWMCOL - 625-6678. SWMCOL collects the paper from clients and sorts it into the various grades. The Company then compacts or ‘bales’ the paper, which is shipped abroad for sale as feedstock in paper mills. SWMCOL is unable to collect the following types of paper: thermal fax paper, carbon paper, tissues, milk and juice boxes and candy wrappers. SWMCOL now collects newspaper.