ABSTRACT
Currently, the whole world is facing an environmental crisis due to the contamination of natural resources. Industries are the major contributors in the national economy of many developing countries; however, these are also the major polluters worldwide due to their potentially toxic wastewater discharged into the environment. The wastewaters discharged from various industries are mainly characterized by the high biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSSs), total dissolved solids (TDSs), total nitrogen (TN), total phosphorus (TP), phenols, and a variety of organic and inorganic pollutants such as cadmium (Cd), chromium (Cr), arsenic (As), mercury (Hg), lead (Pb), etc., as well as total fecal coliforms (Saxena et al. 2015a; Saxena et al. 2016a). The discharge of untreated industrial wastewater causes soil and water pollution and also makes water unsuitable for drinking, land irrigation, fish production, or recreation purposes (Kivaisi et al. 2001; Vymazal 2010). This problem is expected to worsen in the near future, unless measures are taken to control and treat the wastewaters. In most of the developing countries, a centralized (conventional) system is used for the treatment and management of wastewater. However, the operation and management costs of a centralized wastewater treatment system are often high due to its technologically complex nature, and it is therefore not affordable to many developing countries (Massoud et al. 2009; Libralato et al. 2012). Hence, there is a need for a low-cost alternative for the adequate treatment of wastewater prior to its reuse and disposal into the environment.
