Recycling of lignin: A new methodology for production of water reducing agent with paper mill sludge

摘要

Disposal of paper mill sludge (PMS) is a major solid waste problem for the pulp and paper manufacturing industry. In this paper, an innovative way to recycle PMS is presented as follows: lignin is extracted from PMS, and then it is modified by using sodium sulfite and formaldehyde in sequence. The modified lignin is used as an additive for concrete. The water reducing rate reaches 25.2% and the compression strength and reinforcement corrosion of the concrete all conform to the Chinese National Standards. Thus, it results in an innovative method of recycling organic by-products and reducing environmental pollution.