Environmental Studies Program



Kelly L. Emery

Date of this Version



Environmental Studies Undergraduate Student Thesis, University of Nebraska-Lincoln, 2022


Copyright 2022, Kelly L. Emery


This research paper is a comparative meta-analysis of gasification of hydrocarbons in supercritical water, specifically concerning the great pacific garbage patch (GPGP). The research explores two ways to clean up the GPGP while also harnessing the waste as biofuel. This research compares the environmental and economic outcomes between supercritical water gasification and pyrolysis. I will be comparing which thermochemical process of converting hydro-pollution into usable, methane-rich gas is most economically beneficial and environmentally sustainable. The relevance of this use of plastic refuse is that it would not just be diverted to a different landfill or back right where it started in the first place, but rather serve a new purpose: A source of energy that will not run out quickly. The application of this to the Great Pacific Garbage Patch (GPGP) is that this process can be used to clean up the material and give an economic incentive to do so by harnessing energy from the broken-down materials. (Bai, 2019) This is relevant to the GPGP because the materials are not all solids. The GPGP is not a giant solid object floating through the pacific gyre. The Patch is primarily supercritical water and a mixture of water-soluble/broken-down microplastics floating in the east, west, and the subtropical convergence zone of the Pacific Ocean. This breakdown of chemicals makes a thick gelatinous-like material. Because the material is viscous in nature, it is much easier for fish to get caught in the matrix of the supercritical water, consume the material as if it were food, or simply ingest it into their diet – affecting their offspring and the food we eat. Both of these ways of harnessing the energy from the waste tie back to the main problem of cleaning up the GPGP without causing further harm to the environment and solving a growing issue. (Gilsam, 2021) The benefits of cleaning up the GPGP outweigh the negatives. Human health, migration patterns in marine life, economic opportunity, and sustainable energy consumption are just a few of the many ways that this topic can affect everyone, whether they live in a land-locked state like Nebraska, or they are over 50% of the population of the world that lives by a coast.