Aerosol cans – from hazardous waste to household metal waste Development of aerosol can waste management systems in Finland

Background  The metal packaging producer organization Mepak-Kierrätys Oy was founded in year 1997; Finnish Aerosol Association was one of the founder members.  A subgroup, Mepak-Kierrätys aerosol team, to meet aerosol industries interests for aerosol dispenser recycling conditions was founded  Main goal for this subgroup was to develop the metal waste management system in Finland to treat empty aerosol dispensers from industrial and consumer use as normal metal waste and consequently receive better reputation for aerosol products. At this time empty aerosol dispensers were treated as hazardous waste in Finland.

Starting point  The fist step was to source a survey about the possible utilizations of empty aerosol cans in Finland.  This survey was ordered from Association of Packaging Technology and Research, PTR Oy and the costs were FIM (approx €).  From the very fist meeting the goal was also to inform the Finnish Ministry of the Environment about the possible utilizations of aerosol can waste.  The survey was completed in 1999 and it concluded the recycling system in Sweden as the best option for Finland to utilize the aerosol can waste.  In Sweden the empty unpressurized aerosol cans were collected, crushed and mixed with the normal metal waste.  This survey was send to the Finish authorities and first test runs were decided to be initiated at the waste recycling plant (Kuusakoski Oy, Finland).

Recycling plant test’s  For these tests units (approx 1 ton) of specific aerosol dispensers were manufactured to simulate used cans.  In the crushing mixture the ratio of aerosol dispensers was decided to be 2,5 - 5 mass-%.

Recycling plant tests  A metal crushing experiment was conducted by Kuusakoski Oy ; a representative from the Ministry of the Environment was present. Kuusakoski Oy is a recycling services company and leading with recycling of metal based products in Finland.  The test dispensers were mixed together with other metal packaging waste. The packaging cartons burned during this process and some small pops was heard as the cans were crushed.  However one bigger burst stopped the experiment entirely. It was concluded that a 15 g pressurized dispenser content residue exploded during this experiment and therefore it did not correspond to the real situation.

Recycling plant test’s  New test run was scheduled with 5 m 3 of empty collected dispensers. In this experiment the level of dispenser residue was controlled to be max. 5g/can. New test dispensers were mixed together with other packaging waste.  A new run was conducted at the end of year 2000 together with 690 kg of specificly produced aerosol dispensers which simulated used and emptied dispensers from consumers. Before crushing, the dispensers were removed from their original packaging cartons and mixed to 6200 Kg of collected packaging waste. This resulted to a ratio of 10% of aerosol cans in the metal waste mixture.  The duration of this experiment was 45 minutes without any interruptions and it was concluded as a successful one. Also a certificate stating that aerosol cans could be recycled as household metal waste if collected empty and unpressurised was received from Kuusakoski Oy.

Collection of empty aerosol dispensers as domestic metal waste  After a successful experiment a year long field trial in the city of Turku was arranged, in which the waste management company Säkkiväline Oy (currently known as Lassila & Tikanoja Oyj) was a partner.  In this trial domestic metal waste including empty aerosol dispensers was collected from different housing properties. The trial started at the end of January 2001 and it was announced in local press. A handout with instructions for consumers was also delivered to the housing cooperatives concerned (the cost the hand out was FIM).  During the field trial a meeting with representatives from Metallkretsen, Sweden was arranged to receive further experience of recycling empty aerosols. According to the feedback there were no problems in Sweden. The Turku experiment continued until the end of year 2002.

Intermediate Conclusions  As a result of experiments where Finnish Aerosol Association has been involved, receiving conditions for industrial aerosol dispensers were specified: The dispensers must not contain any pressure or product residue and they must be punctured or crushed.  Two sorting experiments of household metal waste were carried out in Turku and The amount of used aerosol dispensers among other small metal waste was very small (0,013 %), but it had tripled between the two experiments. No problems occurred in the Turku crushings.  Kuusakoski Oy made a positive statement about the suitability of aerosol cans in the household metal waste collection. This statement was approved also by other crushing companies (Stena Metalli and Jylhän Metalliromu ) in the year 2003.

Expansion of field trials  At the aerosol team meeting in it was decided to expand the field trials to Jyväskylä, Tampere and Helsinki cities (about citizens). The authorities and communal waste management companies were informed about the trial. The symbols with instructions in recycling containers in the new areas were renewed; this was partly financed by Mepak-Kierrätys Oy.  Another letter was sent to the ministry of Environment. The development in the EU was closely monitored, it was similar to Finland; empty, unpressurized empty containers were considered to be metal packaging and empty dispensers with pressurized residual content hazardous waste.

Results  In 2005 empty aerosol dispensers were approved to become household metal waste in all of Finland, with the precondition that they must not contain any pressure or product residue. Information about this change was delivered to communal waste management companies, authorities (such as the regional environment institutes) and industrial companies concerned. Information was also available in the Internet (  Empty and dry paint containers were collected from consumers alongside the aerosol collection trial. They were also approved to be considered household metal waste in the beginning of the year Information about this change was reported in association with Kuusakoski Oy and Lassila & Tikanoja Oyj.  There have been no reported problems in the recycling of household aerosol cans and paint containers during these four years.  The aerosol team of Mepak has reached its goals.