Title: Regression-based comparative analysis of pollutants in biogas and natural-gas-blend combustion outputs

Authors: Nicholas Bonse; Asfaw Beyene

Addresses: Department of Mechanical Engineering, San Diego State University, 5500 Campanile Dr, San Diego CA 92182, USA ' Department of Mechanical Engineering, San Diego State University, 5500 Campanile Dr, San Diego CA 92182, USA

Abstract: In this work, we compare the combustion pollutants produced from biogas and their fossil fuel counterpart, natural gas, to determine optimum combustion conditions. The study was broken up into pollutant classification, combustion model selection, and regression model analysis. Pollutants are evaluated based on global warming potential, local air quality standards, and effective heat transfer to determine optimum combustion conditions. Four pollutants, carbon dioxide, nitrous oxide, nitrogen oxide, and carbon monoxide are evaluated. For the combustion model, a perfectly stirred Chemkin reactor with kinetic pathways created by the CRECK Polimi Database was selected. The results made it clear that there is no combustion condition in which all the pollutants can be minimised, mainly because the carbon monoxide levels rebound as the combustion temperature falls. However, the study did determine that reducing the combustion temperature and the relative methane content of the fuel - air mixture results in lower pollutant outputs.

Keywords: combustion; pollution; emission; regression analysis; biogas ranking.

DOI: 10.1504/IJGW.2021.118357

International Journal of Global Warming, 2021 Vol.25 No.2, pp.150 - 167

Received: 07 Oct 2020
Accepted: 03 Jan 2021
Published online: 23 Oct 2021 *

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