In the Paper Mill of Bosco Marengo, the technology is implemented to maximize the reduction of the waste of foreign elements and to maximize the recovery of the paper fiber. Through the installation of an innovative pulper plant, the waste is processed in the Paper Mill, here it is washed and treated to recover all the fiber still present. The passage of waste in the trash tower allows to intercept the light fraction that is washed and centrifuged for the recovery of all the fiber that returns again in the production process. The heavy fraction is separated by flotation: in this way the heavy material (stones, metals, glass, chlorine and pvc) falls on the pulper floor and at the end of processing this results in a percentage of residual chlorine of less than 0.5%. The process allows the use of all recoverable fractions and cellulose fibre residues, which were normally disposed of because they were not intercepted.
The raw material returns to be suitable for the next phase of processing with very low humidity values. The new pulper plant and the trash tower allow to process the waste paper for an extreme recovery of all the fiber still present within the waste and to start the non-cellulosic fractions to energy recovery (CSS secondary solid fuel). The waste of plastic and/or methal parts resulting from the processing of waste paper, it is collected and treated separately for subsequent reuse in the form of secondary solid fuel. The CSS is used by Italian and foreign cement plants for the production of electricity essential for the supply of furnaces thus generating a considerable energy saving in the face of the recovery of waste.