2018 ASHS Annual Conference

Modern agriculture faces many challenges for increasing production to meet growing global food needs. Agriculture is water intensive, and changing precipitation and temperature patterns threatens water availability in many parts of the world. Hydroponic crop production is water and fertilizer efficient but is dependent on synthetic fertilizers and good water quality. Urban agriculture can play a key role in reusing water and nutrients in urban environments. Irrigation with municipal wastewater from food industries may be an alternative to reclaiming wastewater and capturing excess nutrients. Brewery wastewater has a moderate nutrient load and a reduced presence of pathogens and heavy metals, which makes it ideal for agriculture. Treating this water in a decentralized way prevents it from further contamination. Decentralized treatment paired with urban agriculture could allow for water reuse and reclaim the nutrients for food production. This has the potential to help enhance food security while protecting the environment and creating new economic opportunities. In this project, we have developed a system where wastewater from breweries is treated in situ and the effluent is used to produce leafy greens and herbs in a non-circulating hydroponic system and substrate based production. Wastewater is first treated using an anaerobic reactor that obtains energy as hydrogen and reduces the carbon load of the water. Treated wastewater is adjusted for the optimal pH and electrical conductivity and used for hydroponic production as well as in soilless substrate-based production. Crop yields are compared to plants grown using a commercial hydroponic solution. Preliminary results show significant lower yields in the plants grown using wastewater. Successful development of the model and greater understanding of nutrient mineralization in hydroponics will allow for a decentralized treatment technology and promotion of soilless urban agriculture.