IGW S.r.l.
Sofia – 9 giugno 2015
PIÙ MODERNI, PIÙ COMPETITIVI, PIÙ FORTI
AMBIENTE ED EFFICIENZA ENERGETICA IN BULGARIA
Organizzazione a cura di
IGW Srl is a service company that deals with the production of energy from renewable sources, environment and consultancy in the technical, administrative, organisational, commercial and management areas in the sector of costruction and infrastructures.
IGW through the experience of its expert technicians, provide:
- Feasibility study and build permitting;
- Plan and design of renewable energy plants;
- Plan and build wastewater treatment plants for agri-food industry - Works supervisor during building of renewable energy plants;
- Technical assistance;
- Upgrading and efficiency of existing plants;
Biogas production from organic waste recycling, and agricultural waste:
Metabolism Metabolism
Organic Waste Manure and slurry
Waste water
Where does this
energy
go ?
Main technologies:
Wet d.m. < 15%
Table 3.2: advantages and disavantages of wet processes(Vandevivere et al. 2001)Criteria Advantages Disavantages
Technology Good knowledge and experience in the process;
Applicability in co-digestion with liquid waste with a high organic matter content;
Short-circuit hydraulic;
Separate phases of floating and heavy matter;
Abrasion of the mechanical parts due to the presence of sand and aggregates;
Pre-treatment of the preparation of waste complex;
Biological Dilution of concentration peaks of the substrate and / or toxic substances that affect the tank;
Strong sensitivity to any shocks to the
presence of inhibitory substances and organic loads variables that come into intimate contact with the biomass ;
Loss of volatile substance biodegradable during the pre - treatments
Economic and environmental
Reduced charges for pumping and mixing , worldwide on the market
High investment costs due to the equipment used for the pre-treatment and for the volumes of the tank ;
Production of high amounts of process water
Main technologies:
Dry d.m. > 40%
Tabella 3.7: advantages and disavantages of dry processes(Vandevivere et al. 2001)Criteria Advantages Disavantages
Technology No need for internal mixers to the reactor;
Strength and resistance to heavy aggregates and plastics;
No short- circuit hydraulic
Wastes with low solids ( < 20 % TS ) cannot be treated by themselves ;
Biological Low loss of biodegradable organic matter in the pre - treatments ;
High OLR applicable ;
Resistance to substrate concentration peaks and toxic substances
A chance to dilute the inhibitory substance and organic loads with excessive fresh water ;
Economic and Environmental
Pre - treatments minimum and cheapest ; Reduced volumes of the reactors ;
Reduced use of fresh water ;
Minimum required heating of the reactor
High investment costs due to the equipment used for the treatment
Biogas production from organic waste recycling :
Business Case: Agrienergia – Bologna (Italy)
Agrienergia Process – Dry anaerobic digestion:
Organic waste recycling
Other organic waste
Anaerobic process C6-H12-O6
Aerobic process C6-H12-O6
Fertilizer
CO2 CH4
Electric Energy Production
from 2.000.000 to 2.800.000 kWh/year
Produzione di Biogas da raccolta differenziata rifiuti
Receiving waste
Biocells of anaerobic process
Compost
Aerobic process Storage of
Ligno-cellulosic waste
Co-generation system
Produzione di Biogas da raccolta differenziata rifiuti
Technical details: Agrienergia
Investment: 4 mln €
Total Area: 30.000 sq.m Potential treatment: 33.700 tons/y Total workers: 8 people Biocells anaerobic capacity: 9.700 tons/y Aerobic treatment capacity: 24.000 tons/y Power generation: 330 kW/h
electricCompost production: 13.500 ton/y
ROI 31/12/2013: 12,59%
ROE 31/12/2013: 8,70%
Produzione di Biogas da raccolta differenziata rifiuti
Digester 1 Technical details
Organic recycling waste 40% / 176,22 m3 / 132,16 tons
Digestate 46% / 202,64 m3 / 151,98 tons
Ligno-cellulosic waste 14% / 61,67 m3 / 46,0 tons
Biogas production m3 17.613,00
Methane production m3 11.342,00
Methane medium production m3/h 24,46
% Medium of Methane in Biogas 64%
Biogas production m3/tons 138,50 m3/tons
Medium temperature in the Biocell 41,5 °C
Time of fermentation – Days 30
Fermentation in Biocell
Produzione di Biogas da raccolta differenziata rifiuti
0 10 20 30 40 50 60 70 80
% Methane
Days
Methane concentration in Biogas
Digester 1 –Methane production performance
Produzione di Biogas da raccolta differenziata rifiuti
Digester 1 – Total production of biogas
0 2000 4000 6000 8000 10000 12000 14000 16000 18000
Biogas Meter Cube
Days
Produzione di Biogas da raccolta differenziata rifiuti
Anaerobic Digestion: Production 2015
Produzione di Biogas da raccolta differenziata rifiuti
Compost produced is a good soil amendent/fertilizer:
:
Parameters U.M. Agrienergia Italian Regulation Limits
Humidity % 14 < 50
pH 6,2 6 - 8,5
Organic Carbon % s.s. 30 > 20
Carbon humic and fulvic % s.s. 10 > 7
Organic N in dry % Ntot 90 > 80
C/N 10 < 25
Salinity dS/m 55 To declare
Plastic glass and metal > 2 mm % s.s. < 0,5 < 0,5
Inert lithoid > 5 mm % s.s. 2 < 5
Salmonella in 25 gr. of f.w. Absent Absent
Escherichia coli in 1 gr of f.w.. CFU/g < 100 < 1000
Index of germination % 86 > 60
Cadmium mg/kg d.m. 0,5 1,5
Copper mg/kg d.m. 84 230
Nickel mg/kg d.m. 53 100
Lead mg/kg d.m. 19 140
Zinc mg/kg d.m. 184 500
Mercury mg/kg d.m. 0,3 1,5
Chromium VI mg/kg d.m. < 0,1 0,5
Produzione di Biogas da raccolta differenziata rifiuti
Localization: San Pietro in Casale, Bologna - Italia
90 mt 270 mt
280 mt
Agrienergia is located close to household and 2 km far from San Pietro in Casale town. Welfare of citizen is guaranted from the waste treatment in close and kept in depression building; polluted air is treated in Scubber and Biofilter before being discharged in atmosphere.
Scrubber
Biofilter
