Nutrient recovery from yellow water to soil-crop systems

The potentials of the nutrient recovered (NRM), via a facile green and sustainable approach from human urine, as a fertilizer in soil-crop system was studied. Nutrient was recovered using a highly decentralized modular reactor, with packed bed of granular gastropod shell. The cultivations of Zea mays (maize) and Solanum lycopersicum (tomato) were the cases studied. The total nutrient composition, the P-speciation, and the safety-risk assessment of the NRM were determined. Using NPK as the standard fertilizer, and a non-fertilized soil as the control, the fertilizing potential of the NRM was evaluated. The influence of the different fertilizer application regimes on the wet and dry biomass nutrient composition, after-harvest soil nutrient composition, and pH values was studied. The NRM contained 106 mg/g of TN and 374.6 mg/g of TP, and the P species identified were Ca-2-P (31.66%), Ca-8-P (14.99%), and Ca-10-P (53.32%). The growth rate of the NRM crops were lower than that of the NPK crops until the 17th day, when the NRM crops grew faster than that of the NPK and control (p < 0.05). The NRM is beneficial to acidic soils and also acts as a slow nutrient releasing fertilizer.

Automated summary

This study investigated the potential of nutrient recovered from human urine as a fertilizer in a soil-crop system. The results showed that the recovered nutrient acted as a slow-release fertilizer and had positive effects on acidic soils.