Fiordelisi demo-site for agro-industrial wastewater reclamation for reuse in irrigation
Fiordelisi is a SME dealing with the production and transformation of horticultures, including conservation and packaging for delivery mainly towards the international market. The company owns large extensions of cultivated land and a factory where the products are prepared for direct consumption. It is located in a region (Puglia, South Eastern Italy) that, albeit being historically vocated to agriculture, lacks primary water resources. In the whole region permanent rivers are absent and the groundwater is heavily affected by seawater intrusion due to overexploitation. In this context all opportunities of limiting the consumption of natural water are critical, and the availability of alternative resources may become a competitive advantage for a business which strongly depends on the sustainability of the water balance. The company has its own wastewater treatment system, mostly treating wastewater from the industrial processing of vegetables (washing, conditioning, cooking, etc.), except a small contribution from the toilets. Treated volumes, strongly dependent on the production processes, are about 300 m3/d on average. The plant is based on a conventional activated sludge system. However, in order to better comply with the local standards for discharge and possibly recover the effluents for irrigation, this plant was upgraded with a tertiary membrane filtration system. Effluents from this tertiary treatment can be stored into existing reservoirs and used for irrigation at test fields owned by the company, where an on-line UV disinfection system has also been placed. This closes the loop and provides an optimized application of the principle of multiple use of water resources. As a matter of fact, in this scheme the same water volumes are used twice, first within the industrial transformation process and then for irrigating the crops that are subsequently processed.
Results obtained so far
On-going research projects are revealing the applicability of tested technologies for the production of effluents suitable for irrigation.
The main innovation proposed at this site is the evaluation of the integration of treated wastewater reuse into the company’s production process, and in particular the assessment of savings in terms of primary resources. This can be further extended towards a general assessment of the influence of wastewater treatment for reuse on the various factors affecting the company’s performance, including energy efficiency, management and operation, external services, etc.. In other words, the sustainability of the proposed approach can be evaluated by running long-term and well monitored experimental activities at a relevant scale.
The whole wastewater treatment and reuse system can be monitored in terms of: (i) process parameters at both the activated sludge and membrane filtration plants, (ii) water quality at the different treatment levels, (iii) soil and crops quality, also with reference to possible accumulation of microbial indicators, organic and inorganic contaminants (including chemicals used in agriculture, salinity, metals, etc.).
Repeatability & Applicability
The approach adopted at this demo-site can possibly be reproduced at similar agro-industrial sites.