Removal of Selected Pollutants in Household Effluent by Solidified Coal Ash and Water Lettuce

The removal of household pollutants of recent concern such as selected pharmaceuticals and personal care products (PPCPs), linear alkylbenzene sulfonate (LAS), and nutrients by solidified coal ash and water lettuce (Pistia stratiotes) was evaluated to possibly enhance conventional sewage treatment system and/or implement in developing countries as a cost-effective method. Porous concrete blocks were manufactured with cement and solidified coal ash, and riverine biofilm was collected by submerging into an urban creek. Relatively fast removal was found for an anionic surfactant LAS and total phosphorus (T-P) while the removal of total nitrogen (T-N) and total organic carbon (TOC) was moderate in both batch and continuous systems. Among the selected PPCPs, more than 98% of triclosan and acetaminophen was removed with the combination of the activated sludge and water lettuce treatment in 120 h of sequential batch experiments.