e compost di qualità in comune di quinto vicentino

MECHANICAL BIOLOGICAL TREATMENT
LANDFILL DISPOSAL
COMPOSTING
Credits: Eng. Pierpaolo Lombardi - Eng. Massimiliano Sacchetti
Last update January 2013
COMPANY PROFILE
Ecologia Viterbo S.r.l. is a private company working in the field of the disposal of urban waste and assimilated waste. It directly manages:
 the mechanical biological treatment plant (MBT) of urban waste located in Casale Bussi, in the municipality of Viterbo, and has a waste
treatment capacity of approximately 216,000 tons/year of MSW which serves the provinces of Viterbo and Rieti.
In the same area it manages the aftercare phase of the landfill for non-hazardous waste, exhausted in 1999.
 the landfill for non-hazardous waste located in Le Formaci, in the province of Viterbo.
Moreover, on 14 September 2012 Ecologia Viterbo S.r.l. required a construction authorization for a system producing quality compost through
organic waste obtained from separate collection (SC-OFMSW) and green waste.
Ecologia Viterbo S.r.l. started its activity in the environmental field in 2004 by taking over the waste treatment plant and the landfill.
Ecologia Viterbo manages its activities following the management system certified according to regulation UNI EN ISO14001:2004 and obtained its
EMAS registration according to regulation 1221/2009/CE. The existence of an environmental policy adopted by the executive/management, annual
plans and targets, a detailed monitoring system and a corpus of computer-supervised working instructions, encourages continuous improvement in
the environmental performance of Ecologia Viterbo and its partners.
According to EMAS regulation Ecologia Viterbo annually publishes an Environmental Statement in order to provide transparent information on its
environmental performance and actions taken to protect the environment.
In 2010 the management/executive approved new policy of Ecologia Viterbo, which is the reference model for the improvement of the company’s
environmental performance.
PRESELECTION AND VOLUME REDUCTION PLANT FOR URBAN WASTE LOCATED IN CASALE BUSSI, IN VITERBO
The mechanical biological treatment (MBT) for urban waste is located in Casale Bussi, in the municipality of Viterbo and was authorized by the
Regione Lazio pursuant to the Det. N. B0346 of 27/01/2010.
The plant, whose customer base includes Viterbo and Rieti provinces, has been working since 1998 and sorts and processes urban solid waste (USW)
by producing stabilized organic fraction (SOF) and refuse
derived fuel (RDF). It has a treatment capacity of
approximately 216,000 tons/year of USW and it is
managed by a direct force work of 18 employees over two
work shifts.
The following types of waste are treated in the plant:
 Urban waste in a narrow sense, from domestic waste
generation.
 Assimilated to urban waste in terms of quality and
quantity, generated from hand-crafted, industrial
productions and similars.
The plant is aimed at:
 Generation of refuse derived fuel (RDF) with high
calorific value and stabilized organic fraction (SOF)
 Recovery of metals.
 Volume reduction of waste.
Remains of waste treatment are permanently disposed of
in the landfill.
The plant consists of:
 Reception station for urban solid waste (USW).
 Automatic selection line.
Fig. 1 - Layout of the plant
 Line for iron recovery.
 Line for RDF generation.
 Line for wet fraction from USW oxidation and selected biomass oxidation.
 Line for SOF refining.
 Line for air treatment.
 Line for the treatment of dry fraction from separate collection.
The area is located in the west region of Viterbo, approximately 8km from the
urban centre and falls within the agricultural area of Viterbo’s municipality along
Via Teverina. The site can be reached both by the Teverina and Ombrone county
Roads.
In the same area Ecologia Viterbo manages the after-care of the landfill for nonhazardous waste. The landfill exhausted its capacity in 1999 and was close in
accordance with the local ordinance n°21 del 14/07/1999.
The landfill is located in the west side of the site and has a surface of
approximately 45,000 m². It consists of a single basin and has a total volume
of 450,000 m³.
Ecologia Viterbo deals essentially with:
 Gathering, removal and disposal of percolating water.
 Removal of surface water.
 Control of phreatic aquifer (level and characteristic of quality.
 Biogas captation and consequent electricity generation.
Fig.2 – Flow chart
In 1999 an assertive biogas captation system was installed and connected to a heat engine for
the generation of electricity to be transferred to the electricity grid.
Fig.3 – Landfill during aftercare phase
LANDFILL FOR NON-HAZARDOUS WASTE LOCATED IN LE FORNACI, IN THE MUNICIPALITY OF VITERBO
Since 1999 Ecologia Viterbo has been managing a landfill for non-hazardous waste in Le Fornaci,
in the municipality of Viterbo.
The area at issue covers the north-west portion of the municipality of Viterbo, approximately 10
km from its urban centre. The site can be reached taking the “Tuscanese” County Road through
the Strada Vicinale della Moneghina or taking the “Verentana” County Road through the
Commenda Council Road.
The disposal area covers a total surface of 50 hectares and it is composed of three basins, two of
which are exhausted and one which has been in use since 2009. The volumes of the exhausted
basins are distributed as follows:

The first basin, located in the northern area of the site, is composed of two sub-parcels with
a total volume of 373,000 m³.

The second basin, located in the southern area of the site, has a total volume of 1,370,000
m³ and it was exhausted in 2009, after the pallet storage of wastes on the top authorized by
the Regione Lazio.
The third basin, the only one still working with a total volume of 850.000 m³, was authorized by
the Regione Lazio with the Dec. n. A3919 del 05/11/2008 which represents a modification and
an integration of the Integrated Pollution Prevention and Control released to the working landfill
by the administrative order of the President Committee of the Regione Lazio n. 28 del
15/03/2007.
The currently operating landfill receives most of the material from the plant
complex. In the past, up to 30% of the material received in the landfill came
from companies other than Ecologia Viterbo but the rate has become minimal
over the years.
The disposal basins are provided with a suitable system of biogas captation and
two biogas recovery systems with an installed power capacity of 3 MW .
The D parcel of the third basin is currently under construction.
The company’s workforce consists of 6 employees (a technical manager, a plant
head, and four clerical workers) also in charge of the weighing management and
registration).
Besides the internal workforce we need to take into account the personnel from
external companies who are in charge of the following operations:

Construction site operations (digging, relocation, waste compaction, etc…)
managed by a specialized external company. At the site a workforce of 5
people is currently employed for these operations.

Management of biogas captation system.

Management of waste produced by authorized companies (leachate,
exhausted oils);

Disinfestation and rat control operations.
Fig. 2 – Layout of the third basin VT3 divided into five functional parcels
ENVIRONMENTAL MONITORING
Ecologia Viterbo, in compliance with the A.I.A., adopts an environmental monitoring plan involving three control phases:
1. Before the operative management of the plant, in order to detect the environmental condition not affected by the new installation.
2. During the management, in order to detect possible alterations in the environment.
3. At the end of the management and during all the period prescribed by the authorities for territory control (phase envisaged for landfills only).
Monitoring of the environmental matrices involved in the presence of the plants
(table on the right) are developed and carried out by Ecologia Viterbo through
innovative methodologies selected in accordance with supervisory authorities in
order to observe possible interactions with the surrounding environment and to
prevent any kind of pollution.
The competent and transparent management
helps to turn people’s suspicions into educated
awareness of the problem with waste and lets
people consider the disposal plant as an integral
part of the infrastructure of our society.
FUTURE DEVELOPMENTS – PLANT PRODUCING QUALITY COMPOST
On 14 September 2012 Ecologia Viterbo S.r.l. required a
construction authorization for a system producing quality
compost obtained through the treatment of organic urban
waste from separate collection (SC-OFMSW) and green
waste.
The plant has a treatment capacity of more than 30,000
tons/year and produces over 11,000 tons/year of quality
compost.
The plant will be built in the municipality of Viterbo, in the
area called “Le Fornaci” and can be defined under the
coordinates:
 Lat: 42° 27’ 22.20’’ North;
 Long: 12° 00’ 12.57’’ East;
The parcel where the plant will be built is located within the
area illustrated in the A.I.A. n.28 of 15 March 2007
regarding the landfill for non-hazardous special wastes
managed by Ecologia Viterbo S.r.l.
The site will be completely separate from the remaining
area and will be destined exclusively to the new
composting plant.
Fig. 1 – Satellite image of the area – The red perimeter shows the area available to Ecologia Viterbo,
authorized by the AIA n. 28 of 15 March 2007. The green perimeter shows the parcel where the plant will be
built (source Google Earth).
Specifically the plant will cover the area filed in the land
register of Viterbo in Foglio n.12, parcel 196.
The plant was designed in line with the BAT
contained in the Regional Plan for Waste
Disposal in Lazio (Piano Regionale per la
Gestione dei Rifiuti nel Lazio).
The treatment process uses technologies
aimed at the simplest operating mode and
process flexibility.
C
F
B
The production of quality compost consists
G
I
D
J
E
of three main phases:

incoming waste grinding;

maturation;

raffinazione del compost;

finished product storage.
The system will allow for composting
approximately 100 tons/day of solid highstrength organic wastes and will be working
300 days/year for a annual total treatment
amount of 30,000 tons/year. The plant will
employ 10 operators over two work shifts.
A
A.
B.
C.
D.
E.
H
LEGENDA:
Entry zone: reception, vehicles weighing;
Offices and accessory services;
Waste reception area;
Pretreatment area;
Mixturing area.
F.
G.
H.
I.
J.
Figura 2 – General layout
Biocells;
Aerated slabs;
Last refining;
Mature compost storage;
Biofilter + scrubber
Fig. 3 – Mass analysis
The plant was designed for a treatment capacity
distributed as follows:
DAILY CAPACITY
Organic material
80
t/d
Residual woody cellulosic material
20
t/d
POTENZIALITÀ ANNUA
Organic material
24.000
t/y
Residual woody cellulosic material
6.000
t/y
The percentage of woody cellulosic material coming
from recycling is about 6 tons/day.
The operating parameters are:
OPERATING DAYS
Work days per week
6
days
Daily shifts
2
Shifts
Lenght of shifts
6
H/shift
Operating days of the plant
300
d/y
Minimum amount of work hours
3600
h/y
The reception, selection and composting sections
will be working two shifts per day, while the
refining section only one shift per day.
01 - PRETREATMENT
Before reaching the composting section, a mechanic blade will send the woody cellulosic material to a chipper, once crushed the green
material will be sent to the mixturing line. Organic waste from separate collection will be sent to the slow-speed grinder. The crushed
material will be treated by a star screen and then sent to the mixturing line by a conveyor belt.
02 - ACTIVE PHASE - AEROBIC BIOCELLS
Also known as “accelerated bio-oxidation” or ACT - active composting time. In the active phase the biomass is positioned in
dedicated bioreactors (biocells in the specific) and exposed to forced aeration.
5 Biocells will be installed in a closed reactor made of concrete with approximate dimensions of 34,00 x 6,50 x 6.00 m. The process lasts
two weeks and the temperature will be kept above 55°.
Every single biocell will be provided with an aeration system which insufflates air through truncated-cone-shaped torches located on PVC
pipes in the pavement.
At the end of the process, during which we had an intense biological activity that facilitated the decomposition of organic material, we will
have a mass reduction of up to 45%.
03 - MATURATION PHASE - FIRST AND SECOND MATURATION SLABS
The compost will be brought by a mechanic blade to the maturation slabs. In this phase called “curing”, after the first process of biodigestion, is sent to a first maturation slab, where it will be arranged in piles not taller than 3,50 m and exposed to forced aeration.
During this period of 38 days, the biomass undergoes an extra maturation with an extimated volume loss between 10% and 20%. The
material is then sent to the second maturation slab where it will remain for 38 more days.
04 - REFINING
After the composting phase of a total duration of 90 days (as provided for by the clause 31 and 33 of the legislative decree 5
February 1997), the obtained material will be sent to the refining phase.
Here there is specific equipment which separates residual inactive woody material to be remixed into recycle and plastic remains from the
compost. The refined compost will be stored on pallets in the dedicated storage area ready to be commercialized.