“…Paper mill sludge (PMS) is a high-volume polluting waste in pulp and papermaking industries, produced at an average rate of 45 kg per ton of virgin papermaking and 300 kg per ton of recycled papermaking. − Globally, paper and paperboard production is anticipated to rise to 550 million tons by 2050 from the current annual rates of 400 million tons, increasing PMS production by 48–86%, presenting a significant disposal challenge for pulp and papermaking companies. − In the United States, 52% of PMS is landfilled; , however, it may be restricted or prohibited, especially in North America, to reduce greenhouse gas emissions and its potential environmental and human health impacts. , PMS contains high amounts of cellulose fibers, varying from 11 to 76% w/w, suitable for cellulose extraction, which offers opportunities not only for the papermaking industry but also for other industries. − Additionally, PMS consists of filler minerals such as kaolin, CaCO 3 , silicate, and TiO 2 that are frequently employed as pigments in papermaking and paper-coating applications, as well as pitch, lignin, and heavy metals. Environmental and public acceptability issues might arise from the heavy metal content of some PMS types as well as from odor, especially when it spreads close to residential areas .…”