Sustainable options of post treatment of UASB effluent treating sewage: A review

The upflow anaerobic sludge blanket (UASB) process is reported to be a sustainable technology for domestic wastewaters treatment in developing countries and for small communities. However, the inability of UASB process to meet the desired disposal standards has given enough impetus for subsequent post treatment. In order to upgrade the UASB based sewage treatment plants (STPs) to achieve desired effluent quality for disposal or for reuse, various technological options are available and broadly differentiated as primary post-treatment for the removal of organic and inorganic compounds and suspended matter; secondary post-treatment for the removal of hardly degradable soluble matter, colloidal and nutrients; and polishing systems for removals of pathogens. Hence, this paper discusses the different systems for the treatment of UASB reactor effluent treating sewage. Additionally, a comparative review, an economic evaluation of some of the emerging options was conducted and based on the extensive review of different integrated combination, i.e. UASB-different aerobic systems, a treatment concept based on natural biological mineralization route recognized as an advanced technology to meet all practical aspects to make it a sustainable for environmental protection, resource preservation and recovering maximum resources.

► The post treatment systems of UASB effluent treatment treating sewage are discussed.
► The NBMS based treatment concept was suggested for the treatment of the sewage.
► High rate micro-aerobic methods were suggested for the up gradation of UASB based existing sewage treatment plants (STPs) to achieve desired effluent quality for disposal or for reuse.
► An economic evaluation of some of the emerging options was described.
► This paper definitely helps the decision or policy makers, engineers and researchers/scientists working in PuSAN sector.