Cleaning Systems for Recycled Pulps from Laser/Xerox Printed Wastepaper, 1993 Pulping Conference Proceedings

Experimental cleaning efficiency results for xerographic and laser printed wastepaper over a wide range of ink particle size were obtained with and without the use of agglomeration chemicals. Subsequently, process simulations were made to compare different cleaning systems using the computer program "General Mass and Energy Balance System (GEMS)." The experimental data obtained from the pilot plant was used as the input data to the computer. The cleaning systems were compared in terms of ink removal efficiency, yield loss, energy cost and capital cost investment.

It is demonstrated that the cleaning removal efficiency is a function of ink particle size. The cleaning system should be placed in the early steps of the recycled process, where large ink particles are present. Based on ink removal efficiency, yield loss, energy cost and capital cost investment, it is demonstrated that the best cleaning process alternative is a four-stage cleaning system using 80 mm diameter cleaners.