Ocean Debris

Introduction

It is estimated that between 4.8 and 12.7 million tonnes of plastic enters the ocean each year. The median value, ~8 million tonnes, would cover the total area of West Yorkshire ankle deep in waste plastics. Plastics such as PS, PVC and PET were first commercially produced during the second world war and became incredibly popular due the ease of manufacturing, low costs, and natural robustness and longevity. As of 2020, about 385 million tonnes of plastic is produced worldwide each year, with production anticipated to grow a further 20% by 2050 [1].

Microplastics (between 1-5mm) which include exfoliating toiletries, microbeads in polishing agents and packaging for small scale fertilisers, have been detrimental to aquatic life [2]. Small enough to bypass standard filtration processes they eventually make it to the sea and are consumed by aquatic animals. The UK has banned shops (with more than 250 employees) from issuing free plastic carrier bags in 2015, then went on further to ban microbeads in toiletries in 2018 [3]. The UK banned plastic straws, drink stirrers and cotton buds in 2019, meanwhile, the EU proposes a ban on the wider category of single use plastics, to commence in 2021.

Ocean currents have led to five plastic accumulation areas, the largest of which, “The Great Pacific Garbage Patch” [4]. It has a total area which is three times the area of France. A Dutch-led initiative is currently underway to attempt to clean up this garbage patch by creating a barrier into which the plastics are moved naturally by ocean currents. However, the Dutch system does not address issues with regards to microplastics and plastics which have sunk to the floor. This still presents a significant issue due to the plastics entering the food chain of aquatic life and affecting migration patterns; having detrimental consequences if not effectively addressed [5][6]. 

Task

The UK government has decided to act. They are seeking a technological solution as a short-term mitigation strategy as opposed to a change in legislation which offers a long-term solution. They come to you, a small engineering firm for an effective engineering solution.

Considerations

·  Context

You must consider what aspect of plastic pollution you aim to reduce and the associated, materials, energy inputs and manufacturing requirements within a realistic timeline.

·  Technical

Clearly identify how and what will be collected. Consider the viability of the project based on types of pollution, location and the time taken to make a meaningful impact.

·  Environment

As this solution aims to minimise an environmental issue, Green campaigners will examine the solution and it must therefore provide a net environmental benefit. Consider how much fuel equivalent the solution will save because of the offsetting of plastics from the ocean; and all the associated costs relevant to your solution.

·  Costs

As well as the project costs there is a potential for income from the plastic collected. Consider how the plastic could be used once scavenged. What is the quality of the scavenged plastic? Will further processing be necessary to become usable or can it be repurposed elsewhere with minimal external input? Are any industries particularly interested in this form of plastic?

·  Sustainability

The solution should aim to be robust with a well-engineered lifecycle, considering the materials used, ongoing maintenance and decommissioning of the equipment.

References

[1] H. Ritchie and M. Rosser, Plastic Pollution. Our World Data. https://ourworldindata.org/plastic-pollution [Accessed: October 9, 2023].

[2] Chatterjee and S. Sharma, “Microplastics in our oceans and marine health,” The Journal of Field Actions: Special Issue vol 19 p 54-61 2019. [Online]. https://journals.openedition.org/factsreports/5257 [Accessed: October 9, 2023].

[3] A. Neslen, "European parliament approves sweeping ban on single-use plastics", in The Guardian, Oct. 24, 2018. Accessed: Oct. 30, 2018. Available: https://www.theguardian.com/environment/2018/oct/24/european-parliament-approves-ban-on-single-use-plastics-uk-eu-brexit [Accessed: October 9, 2023].

[4] J. Jambeck, R. Geyer, C. Wilcox, T. Siegler, M. Perryman, A. Andrady, R. Narayan and K. Law, "Plastic waste inputs from land into the ocean", Science, vol. 347, no. 6223, pp. 768-771, 2015. https://www.science.org/doi/10.1126/science.1260352  [Accessed: October 9, 2023].

[5] The Ocean Cleanup, "Cleaning Up The Garbage Patch", The Ocean  Cleanup. https://theoceancleanup.com/oceans/. [Accessed: October 9, 2023].

[6] Eugene Yang, "Experts unsure if Ocean Cleanup is going to rid the seas of plastic", in ABC News, Sept 22, 2018. Accessed: Oct. 30, 2018. Available: https://www.abc.net.au/news/2018-09-23/ocean-cleanup-great-pacific-garbage-patch-plastics/10285938 [Accessed: October 9, 2023].