Hybrid Hydroponic System: A Sustainable Technology on Facade for Grey Water Recycling for High Rise Buildings

Abstract

Water, the need of life, is a renewable resource covering two-thirds of our planet. However, a very small proportion is effectively available for human use. It is likely to pose the greatest challenge due to the increased demand with population rise, economic development and shrinking supplies due to over-exploitation and pollution. Grey water reuse is a sustainable and attractive option to cope with global water shortages, which can save 40-70% of freshwater by reusing it for toilet flushing and irrigation purposes. On-site grey water management is a critical issue that depends on the technical feasibility of the treatment system. From various studies, it is understood that sustainable technologies like constructed wetlands, reed-bed, phytorid system, hydroponics are efficient in removing pathogens, ammonia, nutrients, phosphorus, BOD, suspended solids and nitrogen compared to conventional wastewater treatment system. Although these technologies are recognized as low-cost, it is not considered as an appropriate option in dense urban areas due to its large footprint. It is required to adapt a technology for the treatment of grey water, which is decentralized, low cost, reliable, low-maintenance, low-footprint and technically feasible. The objective of this paper is to review the various waste water treatment systems and comparative efficiency of hydroponic system for grey water treatment.