Advanced Treatment and Food Production by Hydroponic Type Wastewater Treatment Plant

Abstract

Hydroponic type advanced wastewater treatment system, which consists of a water channel packed with porous concrete and hydroponic type cultivation tanks (HTCT). was developed and its applicability to advanced treatment of secondary effluent and polluted river and drain water was experimentally studied. Porous concrete (PC) provided enough interfacial area for reaeration and enough space for attached microbial growth and improved treatment capability of water channel tremendously. It was revealed that TOC could be removed efficiently under TOC loading rate of 80 mg-TOC/L-day. Owing to the high sludge entrapment capacity of PC, the observed sludge yield (Yobs) decreased to 0.25-0.33 g-MLSS/g-TOC. Crop yield of pak-bung plant during continuous treatment of effluent from water channel was proved experimentally to be 1.18 kg fresh weight/m2 ·month. Hydroponic cultivation of midi-tomato was succeeded by using the effluent from the water channel with low nutrient concentration which indicated that this advanced wastewater treatment process has a high applicational potential for direct purification of polluted river and drain water.