生物多様性、生物探査および開発のジャーナル

Pollution control 2020:Investigation of emissions sources and characterization at Mamelodi Township, Gauteng, South Africa using conditional probability function modelling-Shonisani Norman Singo:nideria

Abstract

Shonisani Norman Singo

ABSTRACT

This paper investigates pollution sources affecting Mamelodi Township within the City of Tshwane in Gauteng province, South Africa. Gauteng province has also the largest population in South Africa. The ambient pollution concentration at the vicinity of Mamelodi depends upon their output of gases from various activities emanates from biogenic and anthropogenic. Anthropogenic activities are the main made sources of emissions such as domestic fuel burning, industrial activities and transport emissions.It is therefore an objective of this study to assess and determine significant sources of emission which are affecting the Mamelodi Ambient Monitoring Station by investigating ambient concentration correlation parameters, pollution roses and probability functions modelling. Investigations will be focus on the following pollutants Sulphur dioxide, Nitrogen dioxide, Ozone and Particulate Matter of less than ten micro diameter. In this study k-means clustering techniques has been applied to bivariate polar plot to identify and group similar features.

Methodology and results: The following methodology will be used in the analyzing of correlation of pollutants at different receptors which are affecting Mamelodi ambient monitoring station. The study uses pollution rose polar coordinates plots to provide a useful graphical technique which provides directional information on sources. Ambient concentration, wind direction together with wind speed can be highly effective at discriminating different emission sources affecting the ambient station. Data collection dated first January 2012 to 30 April 2018. The data processed and imported in the open-air model are presented in comma separated value (csv) format which is extension files of Microsoft Excel. The study has divulge major and minor sources at the received environment. The results has display strong positive correlation of oxides of nitrogen and Nitrogen dioxide. Nitrogen dioxide and nitric oxide sources has display positive moderate correlation of ambient concentrations. The problematic areas emission sources were discovered for ozone and particulate matter less than ten micro diameter per cubic meter on the North west of Ambient monitoring station. Nitrogen dioxide and Sulphur dioxide has reveled local and far sources affecting the ambient monitoring station. The study has thoroughly investigate bivariate polar plot using K-means clustering to discriminate of similarity or dissimilarity between the features which can be identified and grouped.

This Work is presenting at 8th Global Summit and Expo on Pollution Control On August 24-25, 2020 Webinar

Introduction:

Identifying activities and emissions contributing to the ambient air pollution is vital in order to implement proper reduction measures to the source. Ambient air quality is defined as the physical and chemical measure

quality is reported to have deteriorated seriously, especially in urban areas, exposing populations to pollutant levels above the recommended limits (van der Leun et al.,1998). of pollutant concentrations in the atmosphere to which the general population is exposed. Concentrations are vary by wind speed and wind direction plot as continuous surface and surfaces are calculated through modelling using smoothing techniques. In most developing countries, ambient air

1.2 Study Area

Mamelodi township is located in the City of Tshwane in Gauteng Province, South Africa. Gauteng Province is not only the wealthiest province in South Africa (CDP, 2014) it is also its economic hub, accounting for 36 per cent of the country’s Gross Domestic Product (GDP) and 10% of the African continent’s GDP. It is important to understand potential activities at the vicinity of the study area before investigating ambient sources in Mamelodi Township. Identification of current sources is important factors in identifying unknown source that may affect the ambient monitoring station. The activities that has higher probability to affect Mamelodi ambient monitoring station which are located within 5,89 kilometers of the Mamelodi ambient station and there are various sources of emissions. There are three different facilities located on the west of south west of the ambient monitoring stations which are storing and handling of petroleum product such as diesel, petroleum and alumina paraffin. The facilities are located at less than 2,6 kilometers which are Engen Petroleum (Pty) Ltd, Chevron (Pty)Ltd, BP Southern Africa (Pty) Ltd and Total South Africa (Pty) Ltd. Transnet pipelines is for storage and handling of petroleum products located on the south of south west of the ambient monitoring station at 1,92 kilometers away. Above mentioned fuel storage facilities has permanent immobile liquid storage facilities at a same site with a combined storage tanks of greater than 1000 cubic meters. The atmospheric emissions expected from these sites are the vapours from the stored petroleum products and will largely be made up of various volatile organic compounds. There is Afrisam quarry on the north west of the ambient monitoring station located at 5,82 kilometres away and emission associated with quarry are particulate matters and total suspended particulates. On the south west of the ambient monitoring station there is facility called Silverton Engineering located at 3,79 kilometers away from Mamelodi Ambient Monitoring Station. Metallic objects are coated at Silverton Engineering in a layer of zinc by dipping them in molten zinc either in a continuous process or in batches. Pre-treatment of the articles ensure that the surface is in an optimum state to accept the coating involves a series of chemical baths. The first step is to clean the oil on the surface of the article from production which is knows as caustic dip, followed by rinsing to remove the caustic solution. Pickling in acid follows to remove any oxide scale on the surface, followed by fluxing to increase the bonding ability of the zinc and the metal. The articles are then dipped into the molten zinc bath and the final step in the process is quenching. These processes will emit metal fumes and hydrogen chloride and any acid related pollutant depending on the type of acid which requires extraction system to make the workplace safe. The Gauteng province also experiences a high-energy demand and motorization due a combination of factors i.e. rapid population growth, industrialization and relatively high living standard. Gauteng province has the largest amount of vehicles in South Africa from eNatis statistics in the year 2018. The petroleum fuel used by motor vehicles is made up of a mixture of aromatic hydrocarbons and paraffins which ignites at high temperatures in the air. The incomplete combustion of the petroleum in the engine of the vehicle results in exhaust emissions of carbon dioxide, carbon monoxide, volatile organic compounds ozone precursor gases, and particulate matter. Diesel fuel vehicle generally are known of less carbon dioxide which results on high particulate matter at the exhaust. The concentration of air pollution in a given environment depends on both the amount of pollution produced and the rate at which pollutants disperse. Wind direction together with wind speed can be highly effective at discriminating different emission sources.

2. Literature Review