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.