Effect of composting of paper mill sludge for land spreading

Abstract

Paper mill sludge (PMS) has traditionally been landfilled or dumped in the oceans, but the London Convention in Korea strictly banned such disposal methods in 2016. Therefore, the paper industry must find effective ways to reuse PMS appropriately to avoid breaching government regulations against sludge disposal. One efficient way of reusing PMS is composting, which could provide structural and chemical amendment for land spreading. This was evaluated through the measurement of physico-chemical analyses of PMS before and after composting. After composting, no harmful chemical components were detected in PMS, and its particle size and porosity were in the proper range for plant growth. In addition, it was confirmed that the composted PMS greatly contributed to seed germination and plant growth with decreased phytotoxicity, differently from raw PMS.