Integration of crop production with CELSS waste management

Lettuce plants were grown utilizing water, inorganic elements, and CO2 inputs recovered from waste streams. The impact of these waste-derived inputs on the growth of lettuce was quantified and compared with results obtained when reagent grade inputs were used. Phytotoxicity was evident in both the untreated wastewater stream and the recovered CO2 stream. The toxicity of surfactants in wastewater was removed using several treatment systems. Harmful effects of gaseous products resulting from incineration of inedible biomass on crop growth were observed. No phytotoxicity was observed when inorganic elements recovered from incinerated biomass ash were used to prepare the hydroponic solution, but the balance of nutrients had to be modified to achieve near optimal growth. The results were used to evaluate closure potential of water and inorganic elemental loops for integrated plant growth and human requirements.