Waste collection in Thessaloniki

Written by: Tim Byrne | Published:

Thessaloniki is in Macedonia in Northern Greece. Located on the coast, it is the second largest city in Greece and boasts a busy commercial port. The temperature in the Summer reaches 40° and attracts many overseas tourists who stay at seaside towns along the coast of Thessaloniki, as well as day trippers from Halkidiki, a resort near Thessaloniki. With its cosmopolitan nature, it also draws business people who hold meetings at its many venues. The HELEXPO Centre holds exhibitions and conferences all year round, which encourages more visitors to the city and adds to its waste production. Tim Byrne, specialist in waste collection in Mediterranean countries, reports.

The responsibility for waste management in Thessaloniki city and the entire prefecture of Thessaloniki is the responsibility of FODSA, a public company managing waste for the Association of Local Authorities of the prefecture of Thessaloniki. It manages the treatment of waste from the two million inhabitants living in the prefecture.

Recycling systems in Thessaloniki prefecture

FODSA widely encourages the inhabitants of the prefecture to recycle waste and to reduce the volumes of municipal waste currently sent for landfill. They have provided blue coloured 1100 litre containers for the deposit of mixed recyclables, for example, paper, cardboard, ferrous and non ferrous steel cans as well as plastics (PET, HDPE TETRAPAK and LDPE). The blue 1100 litre containers are in communal collection points, next to 660 and 1100 litre green containers for non-recyclable waste.

The city of Thessaloniki collects the mixed recyclables from the blue 1100 litre containers on behalf of FODSA using a fleet of HFAISTOS STEFANOU 16 cubic metre rear loading waste collection vehicles mounted on to Mercedes Axor and DAF LF 15 and 18 tonne two axle chassis. They are fitted with a bin lift with comb and trunnion arms compliant to DIN 30700 and DIN 30740 standards for emptying the blue 1100 litre containers.

The collection service uses a driver and two operatives. The blue 1100 litre containers are positioned at the rear of the collection vehicles by the operatives so they can be emptied by the vehicles' lifting equipment. Once the containers have been emptied, the crew return them to the communal collection point before moving on to the next one.

FODSA also provides the blue coloured igloos for the deposit of mixed coloured glass bottles and jars. These are evident outside hotels, apartments, multi occupant dwellings, restaurants and nightclubs, where large volumes of glass bottles are produced from beer and wine consumption. The City of Thessaloniki provides a tipper truck with a crane fitted behind the cab to empty the igloos on a regular basis. This stops any cross contamination with other recyclable materials from the abrasiveness of the glass which could affect their output quality for reprocessors.

Once the dry recyclables have been collected from the blue 1100 containers and the blue igloos, the recyclable materials are delivered to a materials recycling facility in Sindos in Thessaloniki Prefecture. The paper, cardboard, ferrous and non ferrous metals and the plastics (PET, HDPE, TETRAPACK and LDPE) are separated by eddy current separators before being baled for transporting to reprocessors.

The mixed coloured glass bottles and jars are delivered to a glass processor where the glass is source separated into separate colours for melting and producing new glass materials such as bottles and jars. The reject material from the Sindos facility is baled and taken to the sanitary landfill site for disposal once all of the recyclable materials have been extracted.

FODSA helps Greece move its waste up the waste hierarchy complying fully with the Revised Waste Framework Directive (2008/98/EC) and helping the country improve its recycling rate and provide a closed loop system for its recyclable materials, thus contributing to the circular economy.

FODSA also provides collection points at shopping centres, public buildings and also offices for the collection of batteries for recycling, helping to prevent them being sent to landfill and helping to comply with the Amended Batteries Directive (2013/56/EU). The collection of waste electronic and electrical equipment, such as worn out fridges, freezers and TVs, is also provided for the community, which helps Greece comply with the Recast of the WEEE Directive (2012/19/EU).

Waste transfer station Infrastructure for non-recyclable waste in Thessaloniki prefecture

FODSA has organised a network of waste transfer stations for the efficient discharge of non-recyclable waste by the municipalities across the prefecture. The operation of the waste transfer stations helps provide an efficient waste collection system for inhabitants and helps to reduce the carbon footprint in waste collection vehicles having to travel long distances to the sanitary landfill site.

The main transfer station in the prefecture is Finikas waste transfer station which processes all the city's waste. Built in 1995 in conjunction with Kiggen from the Netherlands and MUT from Austria, the facility is totally covered and sound insulated and has three static compactors which compress waste delivered by waste collection vehicles into hermetically sealed roll-on-off containers. It is on two levels, the upper level is where the waste collection vehicles discharge their loads into the three static compactors and the lower level is where the roll-on-off containers receives the waste falling from the top level by gravity into the hopper of the static compactors.

When fully loaded waste collection vehicles arrive at Finikas, their loads are weighed and the vehicles are directed to one of the three static compactor apertures to discharge. A traffic light system is operated: green informs the driver that he can reverse inside the waste transfer station to discharge the load, red informs the driver of other incoming vehicles that he cannot discharge his load in the aperture of the compactor because the roll-on-off container receiving the waste at the lower level of the transfer station may be full and may be in the process of being exchanged with an empty container.

The roll-on-off containers are moved on a traverse moving frame at the lower level. Once a roll-on-off container is full, it is moved to the right, so an empty container from the left can be moved across to the aperture and locked into place for the fresh loading of waste to continue.

Initially, the waste transfer station only processed waste produced by the City of Thessaloniki and the staff who manage and operate it are directly employed by Thessaloniki City. However, more recently the city of Thessaloniki has come to an agreement with the municipalities of Kalamaria, Pylea, Neapoli and Thermi for them to deliver their waste in their own vehicles to Finikas, thus helping them reduce the carbon footprint by not having to deliver the waste directly to the prefecture's sanitary landfill site. These municipalities deliver their waste to Finikas mornings on weekdays and on weekends at the evening. Finikas is open 24 hours a day, 365 days a year, so it is an excellent waste transfer station in respect of providing sustainable and efficient waste collection and waste transfer systems for the city's collection vehicles as well as those operated by Kalamaria, Pylea, Neapoli and Thermi.

FODSA has also organised waste transfer stations in other parts of Thessaloniki prefecture, for example, Thermaikos. The waste collection vehicles from Thermaikos municipality deliver their waste to a local transfer station where FODSA have constructed a hopper for the discharge of non-recyclable waste by gravity into Kaoussis 56m3 top loading ejector trailers.

The ejector trailers are operated by FODSA and once a waste collection vehicle has discharged its load into the top of the ejector trailer, the compaction ram inside the ejector trailer compresses the waste to the end of the ejector trailer. It is then ready to receive a fresh load of waste from another waste collection vehicle. Once the ejector trailer is full, FODSA replaces it with an empty ejector trailer so that the fresh loading of waste by waste collection vehicles from Thermaikos can continue.

FODSA operates a fleet of Renault Kerax and Iveco Trakker 6x4 double drive tractor units which position empty transfer trailers under the transfer station's loading apertures to enable the fresh loading of waste by waste collection vehicles to continue. They also transport the full ejector trailers to the sanitary landfill site of Thessaloniki Prefecture to be emptied.

Mavrorahi sanitary landfill site - Thessaloniki prefecture.

All non-recyclable waste is delivered to the Mavrorahi sanitary landfill site, which disposes of the waste produced across Thessaloniki Prefecture as well as additional non-recyclable waste from Halkidiki municipalities. The landfill site is operated by FODSA who designed and constructed the landfill to replace the former sanitary landfill site at Tagaredes which closed in 2007 after it had reached its full capacity.

FODSA opened the new Mavrorahi sanitary landfill site in 2008. Civil works were undertaken in advance of the landfill opening at Mavrorahi, including a specially engineered road complete with a bridge for the waste collection and waste transfer vehicles to travel across a ravine to access the landfill site.

A special road network in and out of the landfill site, for example, one road for incoming vehicles and one road for outgoing vehicles which had emptied at the landfill, was also constructed. Two weighbridges were built, one to weigh incoming vehicles and one to weigh the outgoing vehicles so their tare weight could be established. The landfill was lined with a liner and the necessary pipework was constructed for the transport of leachate and methane gas out of the landfill site.

Unlike the former Tagaredes landfill, it is open 24 hours a day enabling the roll-on-off container vehicles to empty containers of waste from Finikas at the tip face of the landfill site 24 hours a day, the Mavrorahi landfill is open from 07.00am in the morning to 5.00pm on weekdays and 07.00am to 1.00pm on Saturdays and Sundays. To make sure that the waste collection and transfer system was not inconvenienced in Thessaloniki city, FODSA allocated an area outside the landfill for Thessaloniki city to deliver fully loaded roll-on-off containers of waste to the landfill at nights and at weekends in the afternoon. Thessaloniki city would provide several slave roll-on-off vehicles to empty the fully loaded roll-on-off containers inside Mavrorahi in daylight hours once the landfill site was open. Empty containers are also stored outside the landfill so roll-on-off vehicles delivering full containers of waste from Thessaloniki city to Mavrorahi on a 24 hour cycle can offload full containers and reload with empty containers to take back to Finikas. This makes sure that the waste transfer station always has empty containers and the waste collection and waste transfer system at Finikas is uninterrupted.

Once waste collection and transfer vehicles have been weighed on the first weighbridge at Mavrorahi, they travel along the haul road to the tip face of the landfill to discharge their loads. The waste collection and transfer vehicles head to the second weighbridge at the exit of the landfill to obtain their weighbridge ticket before leaving the site.

The fresh waste deposited at the tip face of the landfill is pushed into the landfill cell by bulldozers for compaction by a Bomag landfill compactor. Bulldozers also spread soil excavated from nearby the landfill over the fresh waste so that it is covered to prevent seagulls and vermin from ferreting in the waste and spreading disease.

The leachate collected from inside the landfill is treated in a desalination plant next to the landfill site. The desalination plant uses reverse osmosis technology and polishes the leachate to reduce the levels of biochemical oxygen demand (BOD), chemical oxygen demand (COD) and ammoniacal nitrogen in the leachate before being discharged off site through a consented discharge.

Methane is flared off site using a series of flare torches for the different landfill cells. The landfill site complies fully with the requirements of the EU Landfill Directive (1999/31/EC).

The future of waste treatment in Thessaloniki prefecture

The current president of FODSA, Michalis Geranis, says he realises that Thessaloniki prefecture cannot rely on sanitary landfills as the long term solution for treating non-recyclable waste and so FODSA is looking at energy from waste as the longer term sustainable solution to this problem.

FODSA is technology neutral and is considering both mass burn systems as well as emerging technologies such as gasification and pyrolysis.

According to FODSA, by incorporating energy from waste into its longer term waste management strategy, the prefecture will be self sufficient in its own electricity needs as well as the option of the facilities being of a combined heat and power type and qualifying as R1 type energy from waste plants.


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