Presentation on theme: "F. Adani, January 24-25 What digestate is. F. Adani, A. Schievano, G. DImporzano, F. Tambone, B. Scaglia Di.Pro.Ve. Università degli Studi di Milano, Via."— Presentation transcript:
F. Adani, January What digestate is. F. Adani, A. Schievano, G. DImporzano, F. Tambone, B. Scaglia Di.Pro.Ve. Università degli Studi di Milano, Via Celoria 2, Milano website:
F. Adani, January Digestate is not Ingestate Biological process determines chemical and biological modification of raw materials (ingestates) Therefore………… Anaerobic digestion is a biotechnology
F. Adani, January Looking for the Identikit!!!! So… what is digestate ? ? ?
F. Adani, January Degradation The AD process affects: Nutrients Organic matter quality Xenobiotics Organic load
F. Adani, January Degradation : TS and VS mass balances; Organic load: BOD5 and COD. OM quality : biological stability, wet chemical and spectroscopic analyses. Nutrients : mass balance and speciation. Xenobiotic content : direct detection. Our approach
F. Adani, January OM reduction of 60-70% Degradation Mass balance
F. Adani, January Abbattimento COD e BOD Organic load COD BOD
F. Adani, January OM quality Biological stability OM degradability Biological stability OM degradability Degradation processes determine a concentration of recalcitrant molecules. Biological tests - Anaerobic test; - Aerobic test.
F. Adani, January Anaerobic test: potential biogas production It is a good test but it requires time ( 60 dd).
F. Adani, January Anaerobic test (ABP)
F. Adani, January Aerobic test: liquid state respiration index (SOUR) …..it allows a strong time reduction (20h) Cumulated O 2 up-take in 20h
F. Adani, January Aerobic test
F. Adani, January ingestati digestati A case study……….
F. Adani, January Correlation ABP vs SOUR
F. Adani, January Wet analyses Wet analyses Spectroscopic analyses Spectroscopic analyses OM quality
F. Adani, January CS (% TS ) cell soluble 70-90%40-70% OM quality Macromolecular composition
F. Adani, January ADL (% TS ) (Lignin, cutin, suberan, sterol) effetto concentrazione 2-8%10-35% OM quality Macromolecular composition
F. Adani, January OM quality CPMAS 13C NMR Spectroscopy Ingestate Digestate
F. Adani, January Pig slurry Digested Pig slurry
F. Adani, January OM quality PCA analysis
F. Adani, January OM quality PCA analysis Ingenstate Biological stability +-
F. Adani, January Total N ( % TS) Nutrients: quantity 2-5%5-12%
F. Adani, January N-NH 4 (% TS) 0-2%2-8% Nutrients: quality
F. Adani, January Organic N Costante 2-4% Recalcitrant??? Nutrients: quality
F. Adani, January Xenobiotic Heavy metals Cr VI (mg/kg s.s.) As (mg/kg s.s.) Cr III (mg/kg s.s.) Zn (mg/kg s.s.) Cu (mg/kg s.s.) Pb (mg/kg s.s.) Ni (mg/kg s.s.) Hg (mg/kg s.s.) Cd (mg/kg s.s.) Compost limitsBio solid limit ValueElemento Example of digestate analysis: Metal
F. Adani, January absent Hygienic parameters ParameterDigestateLegge 99/92Reg. CE 1774/02 Fecal coliform (MPN/g TS) n.i. Vital Helminthes eggsAbsent n.i. SalmonellaAbsent< 100Absent Escherichia coliAbsentn.i.< 1000 n.i. = not indicated
F. Adani, January Digestate: the Identikit OM Low organic load Medium biological stability Presence of humus-precursor molecules Nutrient content High N content; High agronomic value. Xenobiotic content Very Low
F. Adani, January Amendment properties Fertilizer properties Hygienic product High quality Digestate: the Identikit
F. Adani, January Digestate needs to be qualified……….
F. Adani, January ….… a proposal Limits needed for: Biological stability Biological stability Hygienic parameters Hygienic parameters Heavy metal contents Heavy metal contents 1. Environmental and human protection:
F. Adani, January …. a proposal Parameters should be indicated: N-tot and N-NH 4 ; N-tot and N-NH 4 ; P; P; K; K; OM. OM. Moisture content Moisture content 2. Agronomic use:
F. Adani, January Thank you Dipartimento di Produzione Vegetale Università degli Studi di Milano