Sustainable Application of Industrial Sludge in Agriculture Land

Industrial wastewater treatment is a necessity to protect the environment. However, huge amounts of sludge are a major by-product of the conventionally used industrial wastewater treatment processes. The disposal and/or reuse of the sludge produced by industries such as cement, power plants, tanneries, oil refineries, paper and pulp, and food processing is a matter of concern. Conventionally, three methods are commonly used for the disposal/reuse of industrial sludge: incineration, landfilling, and agricultural land application. Of these options, the application of industrial sludge to agricultural lands is the most sustainable and eco-friendly alternative. Industrial sludge provides nutrients to the soil and reduces (or eliminates) the need for synthetic fertilizers and is also a cost-effective approach. Unfortunately, the sludge may contain putrescible materials, pathogens, heavy metals, etc., and thus can pose a significant environmental risk. This chapter discusses the formation, processing, and pretreatment approaches of industrial sludge, followed by its usage in agriculture. The positive and negative impacts of industrial sludge on soil and plant characteristics are comprehensively discussed.