Mechatronic Design and Control of a Waste Paper Sorting System for Efficient Recycling: Development of a Lignin Sensor to Distinguish Recovered Paper Grades at High Speed, 2003 Fall Technical Conference

The overall objective of this research is to develop an automated waste paper sorting system that is efficient, fast, accurate, and completely autonomous. The research has consisted of developing a fast sensor system to measure the distinguishing optical characteristics of various grades of paper and an identification algorithm for paper grades. In this project, the principles of mechatronic design are being applied to the problem of sorting mixed waste paper. Mechatronics is loosely defined as the synergistic combination of mechanical engineering with electronic and intelligent computer control in the design and manufacturing of industrial products and processes. The optical characteristics of paper used for identification include visible light fluorescence, gloss and color. Visible light fluorescence has been demonstrated to be an accurate and fast method to measure the lignin content in paper. A lignin sensor has been developed that can be used to clearly distinguish between copy paper and newsprint based on lignin content. In this report, some of the refinements involved in the development of a lignin sensor are discussed. Ongoing work involves further refining the sensor for application in an industrial sorting process.