In the two years since the Repesca-Plas project kicked off on1 Jan 2018, marked progress has been achieved, says Aimplas, the Spanish institute that is coordinating the project. The project has also grown: from the 300 kilos of waste originally envisioned, today, fisherman in the ports of Marín (Galicia), Restinga (El Hierro) and Gandia (Valencia) have recovered some five tonnes of marine litter.
The aim of the project, which is being funded by Fundación Biodiversidad, the Ministry for Ecological Transition through the programme Pleamar, and by the FEMP (Spanish Federation of Municipalities and Provinces), goes beyond simple recovery of the waste plastic. The researchers from the various universities and institutes participating in the project are seeking new ways to valorize the plastics recovered from the marine debris.
To that end, after being collected and brought to shore, the researchers methodically analysed and characterised the composition of the debris by type and by geolocation.
The information derived from these analyses will be used to create a marine litter density map of the seabeds studied.
Aimplas said that close to 8,000 items were collected, counted and characterised - ten times what was initially proposed for the collection in terms of weight of marine debris and far in excess of the 1,500 items set down in the project proposal. Plastic bags and food packaging were the two most commonly found waste items, closely following by industrial packaging, plastic sheets and bottles.
Ecotoxicology studies of the debris were also carried out on the different types of debris. No high toxicity levels for the marine organisms studied have been found.
As part of the project, the participants built a composting machine made of 50% recycled material and 50% low-density PE recovered from the debris. In addition, recovered PET has been used to make merchandising items to publicise the project.
During the third year of the project, efforts will be focused on evaluating and establishing the recycling routes available to enable the plastics so recovered to be reprocessed into usable recyclates.
Mechanical recycling technologies will be optimised to boost the percentage of usable plastics recovered from the debris and to improve the property of these materials.
Also, the feasibility of chemical recycling – based on pyrolysis – is also being studied. The researchers are hoping to determine the viability of setting up plants in ports to convert waste plastic into fuel that could be used by sea-going vessels - an outstanding example of how the circular economy could, in practice, work.