Modelling and Analysis of Gaseous Pollutant Concentrations in Ughelli East Gas Plant

Abstract

This study focused on the modelling and analysis of gaseous
pollutant concentrations in Ughelli East gas plant located in Delta
State, Nigeria. Aeroqual multi-parameter environmental monitor
(series 500), was employed to monitor the concentrations of volatile
organic compounds (VOCs), oxides of nitrogen (NO2), oxides of
sulphur (SO2), ozone (O3) and methane (CH4). The concentrations of
the particulate matter (PM2.5 of these gases were obtained at each
monitoring point on daily bases for a period of twelve weeks using
Aerocet-531 SPM meter. Sky master thermo anemometer (SM-28)
was used to obtain the important climatic variables (wind speed,
atmospheric pressure, ambient temperature and relative humidity)
which affect the dispersion of gaseous pollutants. The maximum
concentration of each monitored gaseous pollutant during the twelve
weeks monitoring period was selected and recorded for data
processing. In this study, mathematical models were developed for
predicting each gaseous pollutant such as volatile organic
compounds (VOCs), oxides of nitrogen (NO2), oxides of Sulphur
(SO2), ozone (O3) and methane (CH4). The curve fitting tool in Matrix
Laboratory {MATLAB (2016a)} was employed to select models and
to model the exact mathematical relationship between the pollutant
concentrations and the flare distance; then the pollutants
concentrations were predicted beyond the experimental distance of
500m from the flare point, the models were validated using
coefficient of determination (R2
), and root mean square error
(RMSE). The results showed that R2
ranges from 0.4916 to 0.9821,
while the root mean square error (RMSE) ranges from 2.328 to
6.639. The results obtained from the validation showed good
predictability and adequacy of the models developed.