SWRIPS - Sustainable Water Re-use with Innovative Purification and Sensing system for the agri-food supply chain

Growing anthropogenic pressure and ongoing climate change, which strongly affect the whole Mediterranea area, are eroding global freshwater reserves and water quality thus impacting on soil degradation. Naturally occurring water scarcity may be exacerbated by over exploitation of water resources. According to the FAO, the water use is mainly monopolized by agriculture: between 78 and 84% of freshwater resources are destined for agricultural production. Structural scarcity has repercussions beyond the mere availability of water resources for human use, as it affects all ecosystems, of which man is just a part. Scarcity has direct implications for water and soil quality. The chemical quality of water drops as concentrations of nutrients and pollutants increase. Discharges from point sources of pollution into rivers without adequate dilution results in a greater concentration of the dissolved substances and, in some cases, to a decrease in concentrations of dissolved oxygen. Eutrophication of the system is thus accelerated and the growth of algal blooms and macrophytes becomes a commonplace occurrence. The combined effect of the agricultural impact with the natural scarcity and alkalinity of the Mediterranean soil makes the situation even more serious, creating a vicious and harmful cycle both for the environment and for socio-economic development. In fact, the water is transferred to the roots of plants through osmosis, which is controlled by the level of salts in the soil water and in the water contained in the plant. If the level of salts in the soil water is too high, the water can drain from the roots of the plants into the soil. This results in dehydration of the plant, causing a drop-in yield or even death of the plant. Crop yield losses may occur although the effects of salinity may not be evident. The salt tolerance of a specific crop depends on its ability to extract water from salinized soils. Hence, salinity affects the production of crops, pastures and trees by interfering with nitrogen uptake, reducing growth and stopping plant reproduction and thus worsening agricultural production. Furthermore, the most significant off-site impact of dryland salinity is the salinization of previously fresh rivers. This affects the quality of drinking and irrigation water, with serious economic, social and environmental consequences for both rural and urban communities. Salt interacts with in-stream biota (animals and plants), modifying the ecological health of streams and estuaries. The biggest threat to biodiversity is habitat loss, both on land and in water.

The innovation potential brought by SWRIPS to the water purification cycle of the agro-industrial sector is able to contribute significantly to the irrigation reuse of purified water, to the reduction of the use of external fertilizers through the TWW and re-use of the excess sludge as additional biological soil improver for crop fields and to the reduction of water basin contamination (organic, pesticides, etc.). Specifically, SWRIPS innovation is based on these key elements: ▪ less exploitation of aquifers given by the increase of available water sources for irrigation fed by purified wastewater from the agroindustrial sector; ▪ reduction of operating costs of agricultural reuse of purified water by: - Granular sludge purification technology, able to reduce energy costs and land consumption by about 50% compared to traditional sludge plants; - transportable sewage treatment plants deployed in agro-industrial companies often located in areas adjacent to the fields crops; - the implementation of a system of monitoring and control of water quality in order to constantly ensure compliance with international safety standards for humans, animals and crops; - the use of the excess sludge of the sewage treatment plant as a bio-fertilizer saving the disposal costs; ▪ the establishment of governance agreements between the main key players in the water purification and reuse cycle, capable of reducing the consumption of fresh water and making the effective irrigation use of purified water more efficient and economically sustainable. The first elements refer to the technological component of the purification process, while the identification and choice of an effective governance is crucial for the equally distribution between the actors of the benefits and costs of new technology process.

SWRIPS aims to contribute to PRIMA Operational Objective 2 (WATER AND LAND SUSTAINABILITY Development of a two-stage integrated purification system based on an innovative technology: aerobic granular biomass coupled with nanocomposite-based filters and integrated with a continuous solid-state optical monitoring system. The concept behind the prototype we intend to develop are: recover the water used in the agri-food industry for irrigation purposes, thus helping to reduce the problem of scarcity of freshwater but also the problem of salinization of the soil; characterization and reuse granular sludge of waste water purification process as soil improvers for field crops; produce a matrix for fertilization through the use of excess sludge, without resorting to external fertilizers. These granular sludges, properly used for quality, chemical-physical characteristics, method of use and period of application, are a valuable contribution of humified organic substance to agricultural land going to recover valuable and irreplaceable substances such as phosphorus as well as carbon and nitrogen. One advantage is that nitrogen is released longer, so slow release fertilizers provide the nutrient for a longer period of time. An additional advantage is determined by the lower amount of fertilizer dissolved due to rain or irrigation; provide, thanks to the innovative integrated monitoring system, a continuous control of the quality of the purified water, also guaranteeing the possibility of early warning in case of failure in any of the purification phases. Sludge batch reactor technology (SBR) is a simple, mature and well-established technology. The innovation of granular sludge (GSBR) is easy to implement, even in less developed areas of the Mediterranean. In addition, the system we intend to develop would also have the characteristic of being transportable, so as to be able to optimizeits use based on the seasonality and the characteristics of the water to be treated, typical of the agri-food industry under study (citrus fruits in winter, tomato in spring-summer, oil autumn,etc.) The small granular biomass sludge wastewater treatment plants proposed prove to be flexible, modular, and cost- effectiveness, especially in Mediterranean rural areas is to avoid transporting wastewater at high cost over long distances. Contribution to the expected impacts defined in the thematic area 1 WATER MANAGEMENT purification processes, can be a benefit for rural populations of the inland areas of the Mediterranean, mainly characterized by small and very small farms family that could have great benefits from the construction of plants of this type supplied to local agricultural consortia; Traditionally in the Mediterranean growing countries female labour force is employed in the agriculture. The introduction of smart technologies in the wastewater supply chain will not result in job losses but in a qualification opportunity for female labour; The use of granular sludge as a biological soil improver may contribute to the reduction of the use of excess chemical fertilisers, reducing overall production costs while respecting the whole ecosystems. Organic farming is also a source of greater wealth as well as guaranteeing higher quality and respect for health Pollutants removal and online water purification quality control and early warning system to measure the level of organic pollutants, heavy metals and microorganisms The increase in the stock of water available for irrigation due to the use of purified water helps to mitigate the stress on drinking water. This helps to keep the waterways and lakes intact. In addition, the reduction of nitrogen released into agricultural land contributes to the reduction of eutrophication of surface water bodies.