Maha Ezziddine

Current  PhD research project: Reuse of water and nutrients in soilless growth systems

My PhD project explores how soilless growth systems can be more sustainable by reusing water and nutrients. Currently, soilless growth systems rely on chemical fertilizer which are mined from scarce and non-renewable resources, while large amounts of organic waste streams — rich in plant nutrients — are disposed in the environment resulting in water, soil, and air pollution. Therefore, converting waste streams into valuable fertilizer can not only alleviate the disposal problem, but it also brings economic benefits and addresses future scarcity of non-renewable nutrients and fossil-based fertilizers.

 So far, we developed a process that allows the recovery of nutrient (fertilizer) from aquaculture waste. This process includes two steps: nutrients solubilization using aerobic digestion followed by solids precipitation using the coagulant chitosan, which is a biopolymer that doesn’t react with soluble phosphorus.

The next step is to assess the performance of the reclaimed fertilizer on plant growth using lab-scale hydroponic system.

Ezziddine Maha and Liltved Helge, 2019. Nutrients Recovery from Aquaculture Waste for Use as Fertilizer in Soilless Growth Systems. (presented in the III International Symposium on Growing Media, Composting and Substrate Analysis, Milan, June 24-28,2019).

 Ezziddine Maha and Liltved Helge, 2019. Declining growth rate of lettuce (latuca sativa L.) due to nutrient imbalance in an EC-controlled recirculating hydroponic system. (presented in the III International Symposium on Growing Media, Composting and Substrate Analysis, Milan, June 24-28,2019).

Ezziddine Maha and Liltved Helge, 2019. A method to reclaim nutrients from aquaculture waste. (presented  in 10th IWA International Symposium on Waste Management Problems in Agro-Industries, 19-21 June 2019, Rhodes Greece)