METHANE GAS: A RENEWABLE ENERGY SOURCE

Open Access
Author:
Alghni, Rayyan Saud
Graduate Program:
Environmental Pollution Control
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
None
Committee Members:
  • Richard Christopher Ciocci, Thesis Advisor
Keywords:
  • methane gas
  • environment
  • renewable
  • landfill
Abstract:
A qualitative analysis was made to ascertain what possibilities and prospects exist for generating energy from landfill methane. It was found that, while the general sensibility in channeling a greenhouse gas such as methane to productive use was extremely logical, certain cautionary measures would have to be adopted to safeguard against possible negative side-effects. The analysis was made solely on landfills that were devoted to municipal solid wastes; or at most, agricultural wastes. Landfills with hazardous and toxic waste profiles were not considered. An extensive literature review was conducted and the following was revealed that, i. It was much better to recycle materials that either did not biodegrade easily or that, upon biodegradation, yielded toxic and other hazardous chemicals that threatened landfill sites with pollution. ii. It was also revealed that old landfill sites, even if they produced economically viable quantities of methane, must be adequately safeguarded against possible pollution from by-products of anaerobic fermentation; the principal process that generates methane. iii. It was also determined that new sites must strictly adhere to certain rules and regulations promulgated by local authorities. It was believed that such adherence would ensure that the site accepted only safe waste that broke down into methane gas without complication from toxic and hazardous by-products. Such adherence would also ensure that these future landfills would be adequately insulated against any manner of possible pollution of the environment via air, water and soil media. iv. It was also ascertained that methane produced at landfills should be monitored for toxic and harmful content and accordingly purified to ensure against pollution and damage in the course of utilization. The gas must also be purified of inert components that tend to reduce thermal energy content. v. Small landfills that were considered incapable of producing economically viable quantities of methane must be equipped with methanotrophic bacteria in well-aerated topsoil so that the methane produced in the underlayers would be broken down into harmless components. vi. Lastly, among certain models that could predict methane generation potentials of landfills with specific characteristics, the IPCC (International Panel for Climate Change) 2006, model was proposed as an international tool that could be used in countries where local models were unavailable as it had within its range of defaults that fitted many regions of the world. In all, it is believed that an adequate generalized concept of landfill site safeguarding, collecting of gas, its purification, conveyance to utilities and utilization have been made available. Very few quantitative parameters have been used as these were found too specific for the purpose of the thesis; but again, it is believed that the novelty of the proposed generalized concept adequately made up for the loss of any specificities as these later could be handled at the deployment stage. It is noted though that all specificities that could be made to support the generalized concept, including the process via which anaerobic methanogenic microbials produced methane and the optimal conditions under which they did so, were adequately explored. Methane as a major environmental pollutant can be channeled into productive usage after employment of a few cautionary measures that have been discussed.