Constructed Wetlands for Industrial Wastewater Treatment

15Constructed Wetland Technology for Pulp and Paper Mill Wastewater Treatment

Satish Kumar¹ and Ashutosh Kumar Choudhary²

¹Department of Paper Technology, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur, India

²Department of Applied Sciences and Humanities, HSET, Swami Rama Himalayan University, Dehradun, India

15.1 Introduction

The pulp and paper industry is a growing sector, which mainly depends on natural resources, i.e., water, wood, agro-residues and fossil fuels for the production of paper. The worldwide paper and paperboard production (about 403 million tons in 2013) is dominated by North America, Europe, and Asia. The global demand is projected to grow by about 3% yearly, reaching an expected 490 million tons by 2020 [1].

Pulp and paper mills generate large quantities of wastewater with high organic load and color that may cause serious environmental impacts to the receiving water bodies. Wood preparation, pulping, bleaching, washing, and coating operations are the main sources of pollution [2]. A number of chemical pulping processes are used to convert ligno-cellulosic materials to obtain fibers for papermaking. The pulping process results in lignin network degradation and removal of its soluble fractions from the plant tissue producing unbleached pulp (cellulose 80–90%, hemicelluloses 10–15%, and residual lignin 2.5–4%). The residual lignin is responsible for the unwanted dark color and photo yellowing of the pulp [3]. The chemical pulping processes leave ...