The paper making machines used today are just the industrial version of the handmade paper making machine back in the day. So that paper is made in bulk faster and the demands are met.
History of Paper Machine and Recycling Paper
After some failures faced by Louis-Nicolas Robert, he was finally able to succeed in making first ever Paper making machine. He then sold the patent to Didot, who then took this machine to England from France. In England in 1806 the first new and improved modern paper making machine was made by the brothers Henry and Sealy Fourdrinier.
The first paper recycling at large scale however happened much later, during the First World War. In modern times most of the paper is produced through recycling paper. This is great for our environment.
Paper Recycling Machine and Its Process
There are a number of steps involved in paper recycling. Including collection, transportation and sorting that paper in to different categories. As different kind of category requires a different treatment process in the paper recycle machine. Let us look at the process of recycling paper in the machine after sorting it.
- Pulping: Paper is first chopped by the machine. Then chemicals and water is added. This concoction is then heated to break the paper down quickly. The paper is turned into a mush called pulp or slurry.
- Screening: There are screens with holes of different shapes and sizes in the paper recycling machine, from where that pulp is passed through to remove all kind of contamination. That includes glue and plastic. If the papers have heavier contamination like staple pins, it is spun around in big cylinders using centripetal force. This force throws heavy contamination out of the cone.
- De-inking: As the name suggests, ink is removed from paper in this process. This process is done by the mechanical process and by adding more chemicals to the shreds. Light ink is removed by water and the darker and more persistent ink is removed by air bubbles through a procedure called flotation
- Refining: In this process the pulp is beaten to make the fibre swell. Colour stripping chemicals are added to remove colours from the fibre of paper. The pulp is bleached by using hydrogen peroxide, oxygen and chlorine dioxide. This process makes the paper bright and white.
New Paper is made: In the last step of the paper recycling process, the refined and cleaned paper pulp is ready to be used in the making of new paper. Generally, the pulp is combined with virgin wood fibres. This gives the new paper added smoothness and strength. The recycled paper fibres can be used unaided too, though.
The paper pulp is mixed with chemicals and hot water. The proportion of hot water in this blend is much more than paper fibres and chemicals. After that, the mixture is fed into the headbox. The rest is mentioned below. This will help us understand the working of paper making machine along with further process of recycling paper.
Five Sections of Paper Making Machine
There are four main sections of paper machine as shown in the diagram.
- Wet End or forming section: The fibre slurry first goes in to the headbox or head tank, where a constant pressure is maintained on it. The main drive of headbox is to create turbulence to avoid clumps making and to homogeneously distribute slurry along the length of the wire. A nonstop rotating wire mesh removes water from the paper drawing it out of suspension.
- Press Section: It is the second part of the paper machine. This section removes the remaining water by a system made up of rolls which are pressed against each other assisted by press felts. These absorb the pressed water.
- Drying Section: This part of paper making machine has series of internally stream heated cylinders. The pressed sheets are passed through these cylinders in a snake type manner. This section removes the water to about 6%. The drying sections are usually enclosed to preserve heat.
- Calendar section: This section consists of two rolls. The pressure is applied to the paper to make is smoother and shinier. It gives the paper a uniform thickness.
Reel Section. As the name suggests this section of the paper making machine reels paper or wounds it onto a spool and makes a big roll. At the end the roll hardness is checked.
Sadiq paper is one of the leading paper mills in Pakistan. We are one of the leading paper manufacturers in the Pakistan involved in both traditional and developing markets