The document discusses using ozone disinfection to sanitize recycled waste material. It describes how ozone is produced through corona discharge and its properties. Pilot testing showed treating recycled waste material with ozone for 4-12 minutes achieved 76-89% reduction in bacteria. A proposed 40,000 ton per year facility would use ozone treatment to produce high quality refuse derived fuel from dry recycled waste fractions. The facility would be powered using electricity and heat from an on-site landfill gas generator, making it carbon neutral.

1. RDF OZONE DISINFECTION
Ing. Roberto Palazzolo – SRF ENERGY S.r.l.
VENICE 2008 - 17/11/2008

2. RDF typical Production routes
Drying & Sanification through
Sanification and Drying on RDF
Bio-stabilization of MSW
Aerobic stabilization
MSW
MSW shredding of Organic fraction
Mechanical
bio-stabilization
Sorting / Refining
Inert Metals Stabilized
Mechanical Raw Organic
Sorting / Refining RDF Fraction
Ozone
Sanification
Metals Inert Physical
Drying
RDF
High quality RDF High quality RDF
Dry & Sanitized RDF
High
Calorific High Calorific
Waste Waste

3. Ozone Properties and Production
Table 1
Molecular weight 48g/mole
Density relative to air 1.66
Specific weight at 0°C and 760 mm HG 2.143 kg/mc
Formation heat 34.5 kcal/mole
Boiling point -112°C (dark blue liquid)
Freezing point -193°C (dark red solid)
Corona discharge
Low voltage electrode
O 2 Discharge section O +O
2 3
Dielectric
High voltage electrode

4. Experimental Equipments used in the study
Shredder / RDF
Ozone testing unit
Pilot contact reactor

5. Technology validation in the pilot plant run..........
Oxygen Flowrate 3 lt/min
1E+07 100 1,00E+10
95
90
85
80
75 1,00E+09
70
1E+06
% Removal Efficiency
65
60
55
CFU/g
48 h 72 h
CFU/g
24 h 50 1,00E+08
45
40
35
1E+05
30
25 1,00E+07
20
15
10
5
1E+04 0 1,00E+06
blank 24 48 72 hours 0 24 48 72 110
A@1 lO2/min 2E+06 2,40E+05 2,67E+05 2,79E+05 Blank 1,31E+09 9,80E+08 1,50E+09 1,60E+09 1,40E+09
B@ 2 l O2/min 2E+06 2,40E+05 2,67E+05 2,79E+05 A - contact time 12 min 1,80E+06 2,50E+06 2,00E+06 2,20E+06 4,90E+06
Ef f.% A 79,6 77 76 B - contact time 8 min 5,10E+06 5,90E+06 6,40E+06 5,80E+06 9,30E+06
Ef f.% B 89,8 89 88 1,00E+07 1,10E+07 4,80E+07 5,50E+07 1,00E+08
C - contact time 4 min
Different O2 (i.e. O3) flowrates Different contact time
Contact time: 12 min O2 flowrate: 3 lt/ min

6. Magliano Project : 40,000 ton/y Structure quality RDF
Project
High
.......The First industrial scale 40% 60%
Plant will be operated by SRF
Energy in the new Magliano (CN)
high quality RDF plant
One of the most important waste management company in Italy
Technology company and RDF-HQ trader
General Overview
Existing Dry fraction production plant :
UNIECO is a 20 years concessionaire
Upgrading to High quality RDF production
Landfill expansion with biogas energy recovery

7. Magliano Project : 40,000 ton/y High quality RDF
Post-processing of the Dry fraction from an existing MBT plant
The system is designed in order to meet strict specification for:
 Size : < 20 mm (15 mm optional) , size is controlled by the bottom sieve
 Odors and Biostabilization: Ozone technology from PRAXAIR is applied
 Moisture: Physical drying technology will be applied
 Calorific Value: Plastic adding by weight controller has been foreseen
 Chlorine: Daily lab test on automatic collected samples will be done

8. Magliano Project : 40,000 ton/y High quality RDF
Ozone – RDF screw contactor
Ozone Destroyer
RDF Capacity: 7,5 ton/h
O3 production: 10 kg/h
Ozone Reactor

9. Magliano Project : 40,000 ton/y High quality RDF
electricity Cogeneration of Heat and
Electricity
The plant will run using the electrical
and heat energy produced by the
landfill gas generator. The electricity
produced will be 450 kWe, together
with Heat up to 650 kWth.
Heat
Heat
The remaining required heat to
Heat dry RDF will be produced by a
biomass boiler
CO2 Emitted = ZERO