Reusing agro-industrial wastewater for vegetable production
4 June, 2050
DEMOWARE
Waste water source
Fiordelisi is an agro-food industry located in Apulia (Southern Italy). The company grows, processes, packages, and does the marketing of preserved, ready-to-eat vegetables. There are four steps of the process that generate waste water streams: washing, acidification, packaging and pasteurization. Salt is present mainly in the washing stream, oil in the packaging one.
The company’s processing activities use groundwater. Until 2012, the industrial wastewater (up to 80,000 m3 per year) were discharged into the surface water after a primary and secondary wastewater treatment. From 2012, a full-scale tertiary treatment was added to reuse a share of the company’s wastewater for vegetable crop production (field tests).
The Fiordelisi company has an annual wastewater production of 80,000 m3 which is fully treated with primary and secondary treatments. A share of this capacity undergoes a tertiary treatment.
Distribution System
Effluents from the tertiary system can be stored in existing reservoirs and used for irrigation at test fields. At the test fields, an additional UV-disinfection system is in place.
Farming system
Tomato and broccoli crops were cultivated, in close succession, under a structure covered with an antihail net. Irrigation was applied through drip irrigation. The field tests investigated the use of three types of water: Groundwater (GW), secondary treated water (SW) and tertiary treated wastewater (TW).
Waste water treatment description
Nutrient removal : Small, but not statistically significant, reductions of nitrogen and phosphates were also observed, of about 29 and 80%, respectively.
Pesticide removal : none
Disinfection : Ultrafiltration (8 modules with nominale surface of 60m² each).
On-line UV-treatment (6 mercury-vapour lamps, 200W each). The UV-disinfection operated “on-demand” according to the irrigation volume supplied to the crops.
Suspended solids removal : Screening (0.5mm), Activated sludge system composed by anoxic (130m³) and aerobic (520m³) phases. Aeration provided through fine bubble diffusers, secondary sedimentation assisted by adding aluminium polychloride.
Other : Deoiling through gravity separation, pH adjustment by dosing sodium hydroxide
(Schematic presentation of the system at the bottom of the page)
Capacity
The Fiordelisi company has an annual wastewater production of 80,000 m3 which is fully treated with primary and secondary treatments. A share of this capacity undergoes a tertiary treatment.
Extent of the agricultural beneficiaries
Irrigation tests were performed in an open field of about 5.000 m².
Costs
The cost of the tertiary treatment was 0.61 euro/m³ (this includes 0.23 euro/m³ and 0.38 euro/m³ for capital and operational costs respectively).
Type of agreement
No agreement needed, since both effluent and fields are from the same owner.
Scientific results
Scientific report and peer-reviewed papers:
Martinez, X., Bosch, C., Terre, M., Biel, C., Vergine, P., & Pollice, A. (2014). Innovative schemes for water reuse in the agricultural sector - DEMOWARE D1.5 (Vol. 1)
Gatta, G., Libutti, A., Gagliardi, A., Beneduce, L., Brusetti, L., Borruso, L., … Tarantino, E. (2015). Treated agro-industrial wastewater irrigation of tomato crop: Effects on qualitative/quantitative characteristics of production and microbiological properties of the soil. Agricultural Water Management, 149, 33–43. https://doi.org/10.1016/J.AGWAT.2014.10.016
Libutti, A., Gatta, G., Gagliardi, A., Vergine, P., Pollice, A., Beneduce, L., … Tarantino, E. (2018). Agro-industrial wastewater reuse for irrigation of a vegetable crop succession under Mediterranean conditions. Agricultural Water Management, 196, 1–14. https://doi.org/10.1016/J.AGWAT.2017.10.015
