Better sorting for better raw material and better recycling

摘要

Paper is the most recycled product in Europe, and Europe is the global champion in paper recycling with an average rate close to 69 % in 2011. The next commitment of the paper industry is to achieve a target rate of 70 % by 2015, and experts have estimated that the maximum recycling rate could even be 75 %. To achieve these goals, collection has to be increased, and the capabilities, opportunities and qualities of sorting must be improved. This is even more complicated than collection systems in Europe vary greatly from one country to another. A solution, to address this issue, is the development of new and improved measurement technologies for automatic recovered paper sorting. The challenge is to perform a better sorting, in order to ensure a better raw material quality, and, finally, a better recycling. CTP works on this subject for some time, through various projects, including a partnership with a French manufacturer of sorting machines, which is a world leader in this field. A sorting machine is conventionally composed of two parts: a "detection" part (by optical sensors) and an ?action / ejections part (by compressed air, for example). CTP has worked on optical sensors part, identifying and investigating innovative methods and approaches in order to determine the most efficient ones for the development of new sensors based systems for raw material characterisation. This paper presents the main methods retained (near UV fluorescence, visible image analysis, and especially Near Infra-Red spectroscopy) with their interests and possible applications for the sorting of recovered paper.