Dunapack Ltd. - Manufacturing process

During the pulping process, a predefined mixture of recovered paper is broken down roughly using water and mechanical energy. The roughest impurities are then removed from the resulting pulp with the aid of a wire sieve. Afterwards it is put through a screening drum and undergoes coarse and fine screening. So-called reject pulp is the waste material separated by the various screening processes.

The headbox evenly distributes the pulp slurry on a moving sieve or “wire”. Water is removed from the pulp by a drainage foil. Here an individual wire is used for each layer of paper, depending on the technology involved and the type of paper. The paper web enters the pressing section of the machine with a moisture content of about 80%. By applying hydraulic pressure, the moisture content of the sheet is reduced to approximately 50%. The high-pressure press reduces the moisture content to 45%. The paper machine is controlled by personnel in the control room on site with the aid of the most modern control systems. In the following drying section, running the paper web over cylinders heated to approximately 140 °C further reduces the moisture content. In the subsequent size press, sizing, that is, starch or glue, is applied to the surface. This allows specific characteristics of the paper to be improved. Starch is applied to the upper and lower surface.

At the end of the paper machine, the sheet is wound onto a reel. The reel is then mounted in the roll-slitting machine (rewinder) for rewinding. During rewinding, knives are used to slit the sheet into rolls of the desired width. Upon completion, the rolls are fitted with sleeves and plastic strapping and labelled. A conveyor belt transports the finished rolls to the warehouse, where they are stored according to paper type and customer and kept until the order is called.