Paper is sent back for reprocessing into newsprint. Every tonne of paper that we recycle saves approximately 17 trees. Approx 80% of the paper that we sort through the MRF goes to a paper mills where they are able to deal with all types of mixed paper for turning into newsprint paper.
Once loaded into walking floor lorries of approx 27 tonnes/load some of your paper is transported and loaded onto ships that have brought newsprint paper in to this country. The paper is shipped in loads of approx 5,000 tonnes to Sweden for re-pulping and recycling back into paper.
The Swedish paper mill that receives our material runs its entire operation in a bid to cause the least environmental impact as possible. All water is re-circulated and used to produce hydro electricity.
How Paper is Made
A schematic of the papermaking process is shown below. In this case, a chemical pulping process is depicted. However, if the digester, blow pit, and washer were replaced with a mechanical refiner, the drawing would also describe a mechanical pulp and paper mill.
Note that once the wood has been converted to pulp, the pulp is beaten (more on this in a moment), refined in a Jordan refiner, and then sent to a large machine where a slurry of fiber is metered onto a moving wire. In this machine, called a Fourdrinier, a slurry that is 99% water by weight flows from the head box onto the wire, after which suction boxes pull water rapidly away. The result is a fiber mat that is then pressed, dried, coated and/or sized, re-pressed, and cut into desired sizes of paper.
A Fourdrinier unit is pictured here. A slurry of fibre is being metered onto the moving wire at the far right in this picture, with movement of the wire toward the left. The drier units can be seen at the far end of the production line.
The beating and refining processes are very important in the papermaking process. An examination of beating, in particular, provides several insights as to some of the technology involved.
This is a photo of softwood that has been chemically pulped. Note that the fibres are straight, smooth, and largely undamaged.
For the most part, however, smooth surfaces and rounded, undamaged fibre are not what is needed in making a quality sheet of paper. Fibres must be flattened to increase the contact area (and thus the bond potential) between them.
Flattened fibres can be readily seen in this highly magnified photo of the surface of paper.
Moreover, by unravelling micro fibrils from the cell walls, surface area (and thus hydrogen bonding potential) can be greatly increased as illustrated by this photo of mechanically produced fibre.
The way that fibres are flattened, and subjected to a mechanical rubbing action that unravels micro fibrils, is through the use of a beater. A simple beater (a Hollander beater) is shown here. A slurry of fibre goes around and around in the tub, each time passing between a fixed bedplate and the ribs of a rotating beater wheel. The opening between the bedplate and wheel is set to about the width of a single wood fibre, meaning that fibres are pounded and deformed with each pass.
The longer fibers remain in the beater, the more beat-up they become, and the more the surface area of the fiber is increased.