UNIVERSITA’ DEGLI STUDI DI MILANO
The DISAA – Ricicla Group of UNIMI develops its activities in view of a development, through scientific research, of the knowledge regarding agricultural, forestry, farming, environmental and energetic systems, based on a multi-disciplinal approach, for the promotion of efficient management of complex agricultural systems. The ‘’Agriculture and Environment’’ and ‘’Biomass and Agroenergy’’laboratories, are equipped with analytical instruments like Solid State NMR, DRIFT, GCMS, GC, GCMS-MS, HPLC, nanoscale porosimeter, elemental analyzer and ICP/MS. The ‘’Biomass and Agro-energy’’ laboratory is equipped with lab-scale reactors for bioprocess monitoring devices for ammonia, methane and N2O monitoring. The research team is formed by 1 full professor, 3 researchers and 2 post-docs. They have developed in the last 25 years, knowledge in the field of biomass use and re-use, with particular attention to energy production and organic carbon cycle and impacts on water soil and air of digestate, slurry and compost. Recently, the first full-scale plant for bio-hydrogen and bio-methane integrated production has been developed, unique in Italy and EU. Besides, another full-scale application has been developed, based on chemical-physical separations, for renewable nutrients production from waste biomass.

The Project POWER, funded by Cariplo Fundation
Description:
The excessive use of fertilizers and livestock manure have contributed in recent decades to generate a pollution process to water bodies known as eutrophication. The main causes are the uncontrolled input of nutrients, manly nitrogen (N) and phosphorus (P) coming from soil water-leaching and/or soil water-run-off. Anaerobic digestion (AD) has been reported to modify chemical-physical properties of slurries, so that P removing can be enhanced a lot.
According to these priorities POWER project aims to develop techniques able to remove P from digested animal slurries by precipitation of P as salt (struvite), producing renewable fertilizers. The effect of P removal on water pollution and environmental impacts will be considered as well.

Objectives:
The POWER project aims to develop a useful system to recover phosphorous from animal slurry by AD pre-treatment, with the double goals to reduce soil and water P-pollution, and to recovery two renewable fertilizers: 1. organic-mineral fertilizer (solid stabilized separate fraction of digestate) and 2. mineral fertilizer - “struvite” -, by successive treatment of the liquid fraction of digestate. Moreover POWER project has the objective to better understand the fate of P fertilizers in soil and the potential of pollution, i.e. P-form vs. P leaching and/or P-run-off.

Strategy
The project consist in 5 WP. WP1 investigates the effect of AD on P-form (chemical and spectroscopic techniques) with reference in producing a solid fraction representing an organ-mineral-P fertilizer. WP2 is devoted to removing residual P form from the liquid digested fraction by optimizing P salt precipitation, i.e. struvite. (mineral P fertilizer). Lab-scale trials, varying process parameters and using different co-reagent, will outline optimal combination to remove until 90% of total P-slurry. WP3 is devote to test P-fertilizers obtained by both chemical and vegetative tests. In addition P speciation in soil treated with P-fertilizers produced, will be compared to with soil that received excesses of P by animal slurries in order to rank pollution potentiality. WP4 will devoted to detect the effect of P removal on water pollution and environmental impacts by LCA methodology. In the last WP5 is dedicated to the dissemination of results.

Results
The expected results are as in the following:
- to develop efficient and cost effective system able to remove phosphorus from animal slurry by using the anaerobic digestion;
- improve the management of digestate avoiding overload of phosphorus in the soil and subsequent transport in surface water bodies and consequent eutrophication;
- provide an alternative to minerals phosphate fertilizers, currently produced from non-renewable resources (phosphate rock) nearing depletion.
- To rank environmental benefit coming from P reduction in slurry producing P renewable fertilizers by Life Cycle Analysis (LCA) .

Country: Italy

Organization Type: University

Email: fulvia.tambone@unimi.it

City: Milano ,Via Celoria, 2 Google map

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