Life cycle assessment of ships with special consideration of ship scrapping

Abstract

Global trade is depending on the seaborne transport of goods. Over two thirds of the transport worldwide is carried by ships. After the financial crisis in 2008 the worldwide economy experienced turbulences which had a direct impact on the volume of trade. All of a sudden there was an overcapacity of ships cruising on the oceans of the world. Many of the older ships were decommissioned and scrapped. Numerous scrapyards are in South Asia, where the ships are dismantled under harsh working conditions and with no environmental protection measures. A lot of these scrap yards are merely beaches where the ships are beached (beach-breaking yards) and disassembled manually. International agreements and efforts exist to tackle this kind of end-of-life treatment of ships which is dangerous for humans and the environment. One example is the Basel Convention to control hazardous waste, to which disposed ships also belong. In 2009 the Hong Kong Convention was adopted, which aims at reducing the risks to human health, safety and to the environment during the recycling of ships. Just recently the European Commission has adopted the EU Ship Recycling Regulation to reduce the negative impacts linked to the recycling of EU-flagged ships. The Regulation sets out a number of requirements for European ships, European ship owners and ship recycling facilities. Confronting existing challenges of ship scrapping and the international activities to tackle these challenges a literature research is performed to assess in what way the end-of-life of ships has been covered in LCA studies. Based on these findings an own approach to an end-of-life (EoL) assessment is set up and illustrated by an example. In order to develop a comprehensive assessment of the EoL of cargo ships, a simplified model based on the mentioned preexisting information is created. All three phases: ship building, ship operation and ship scrapping are taken into account. Two scenario groups for the ship scrapping were defined, with different approaches to re-use and recycling. The overall contribution of the end-of-life phase to the life cycle (construction of the ship, Use, EoL) of a ship is ranged and evaluated. The results of the assessed scenarios confirm that the re-use and recycling process is environmentally preferable. However, the processes and human labour have not been taken into account yet. The overall impact on the lifecycle remains negligible within the assessed impact categories. A more significant impact of the EoL on the lifecycle might be seen if other impact categories, such as indicators for resource efficiency are taken into account.