Description
ABSTRACT
Generator exhaust gas emissions are becoming a challenge in urban areas due to rapid increase in generator usage. Therefore, the focus of this paper is to evaluate the actual level of emissions for both petrol and natural gas fueled generator. Exhaust gases (i.e. CO, CO2, NOX and HC) were randomly measured from 200 generators using the exhaust gas analyzer. Significant differences were observed in the concentrations of pollutants measured based on the generator engine capacity for both gasoline and natural gas fueled generators. In addition, the differences in emission pollutants concentrations between gasoline (or petrol) and natural gas are also significant. The study concludes that emission levels from natural gas generator are lower than gasoline ones and could be used as alternative fuel in Nigeria.
TABLE OF CONTENTS
COVER PAGE
TITLE PAGE
APPROVAL PAGE
DEDICATION
ACKNOWLEDGEMENT
ABSTRACT
CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND OF THE PROJECT
- STATEMENT OF THE PROBLEM
- AIM AND OBJECTIVES OF THE PROJECT
- SCOPE OF THE STUDY
- SIGNIFICANCE OF THE STUDY
CHAPTER TWO
LITERATURE REVIEW
- REVIEW OF THE STUDY
- REVIEW OF RELATED STUDIES
- NATURAL GAS – GLOBAL WARMING EMISSION
- AIR POLLUTION FROM NATURAL GAS
- SOURCES OF GREENHOUSE GAS EMISSIONS
- EMISSION FROM FUEL
- TYPES OF GREENHOUSE GAS EMISSIONS
CHAPTER THREE
METHODOLOGY
- DESCRIPTION OF STUDY AREA
- POPULATION,SAMPLING AND SAMPLING TECHNIQUES
- DETERMINATION OF EXHAUST GASES CONCENTRATIONS
- PROCEDURE
- DATA ANALYSIS
CHAPTER FOUR
4.1 RESULTS AND DISCUSSION
CHAPTER FIVE
- CONCLUSIONS AND RECOMMENDATION
REFERENCES
CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND OF THE STUDY
The exhaust gases emitted by generators contain some levels of pollutant concentration which affects the health of humans, plants and animals. The pollutants exist in the form of nitrogen oxides (NOX) ozone (O3), unburnt hydrocarbons (HC), carbon monoxide (CO) and particulate matter (PM). These pollutants are formed as a result of burning hydrocarbon fuels as their energy source and contribute significantly to atmospheric pollution in both developed and developing countries(Bell,2011). Among these various pollutants, NOX and PM were of much significant because of their implication on human health and the environment. Different studies showed that PM had effect on human health likewise the environment (Chapman, 2017). Epidemiological studies showed that there is a relationship between PM exposure and acute respiratory diseases, cardiovascular and lung infections (de Haan et al., 2010).
Because of these health risks, various emission reducing strategies have been proposed in developed countries. These included new technologies, where fuel consumption has been minimized using dynamic optimization (Saerens et al., 2019), applying new legislative standards for newer generators (Arteconi et al., 2010) and using alternative fuel systems, such as using natural gas (NG), liquefied petroleum gas (LPG) or bio fuels in heavy-duty generator instead of the conventional gasoline or petrol(Lopez,2019).The use of alternative fuels is becoming widespread in developing countries.
In Nigeria, natural gas usage as an alternative fuel for commercial generators especially is on the increase.However, a study conducted by Biscoff et al. (2012) shows that natural usage as an alternative generator fuel is illegal. This is because governmental policy concerning natural was centered on domestic or residential consumption.
In developed and some developing countries, the change from petrol as generator fuel to natural gas is because of its environmental benefits. A study by Gamas et al., (2019) indicated that recent moves towards the use of natural gas than petrol is the perception that natural gas is a cleaner fuel. It has been widely used as an alternative generator fuel in the United States of America, Canada, the Netherlands, Japan and several other countries (Ristovski et al., 2015).
In Nigeria, many industries convert their generators for natural usage because it improves fuel economy relative to petrol. This implies that whiles other countries are shifting to natural gas usage as alternative generators fuelto safeguard their environment or reduce emission pollutants levels; industrialist in Nigeria are converting their generators to use natural because of more profit and better fuel economy.
Generators emission rate is influenced by some factors. It largely depends on equipment, engine characteristics, vehicle maintenance,and weight, all correlate to the emissions. In addition, the engine size also affects the functioning of emission control equipment (Beydoun,2014).Furthermore, poor maintenance and age of generators also contribute significantly to the emission of all classes of generators. A study by Perry and Gee (2015) also shows that fuel qualityhasadirecteffectongeneratorsexhaustemission.AccordingZhang(2011)emissions may increase as generators spend more time in operation and undergoing numerous acceleration and deceleration events.In Nigeria, there is little or no documentation concerning generator emissions,especially for environmental protection and health safety.Therefore, the focus of this study is to assess the emission levels from different classes of generators using petrol and natural gas.
1.2 Statement of the problem
Environmental pollution is one of the alarming global concerns in the present situation, and it exists everywhere in the air, water, and land. People inhale about 10,000 liters of ambient air on a daily basis, which is in direct contact (SalviS, 2017). So, if the air is polluted and people have to get exposed in that air unintentionally, it will create a more devastating effect on them. Around 92% people of the world reside in the areas, where the air quality exceeds the limit, which is approved by the WHO, according to a recent model of WHO air quality (DinhT.-V. et al., 2016). Every year, 7 million deaths occur globally, due to the exposure of the people in the outdoor and indoor polluted air.
For this reason, the focus on this pollution is one of the primary concerns. Air pollution can be classified into categories, (a) outdoor, and (b) household air pollution. Deaths from the exposure to ambient (outdoor) air pollution each year is 4.2 million (HuangY. et al., 2018). The sources of outdoor air pollution are industry, energy production plant, transport, waste management, dust, agricultural waste management practices, and household energy plants (DeshmukhP. et al., 2020). Among them, industrial sector is widely recognized as a significant and growing source of worldwide air pollution . In the industrial sector of the cities of many developing countries, the unsustainable population of generators has increased the air pollution emissions level tremendously, resulting in extreme health risk issues (LiuG. et al., 2020). The primary reasons behind a large number of generators are rapid used in many developing countries’ cities and socio-economic growth among the people. Emission from the industrial sector is a significant contributor to outdoor air pollution, which is the leading risk factor for the environmental safety of the world. Generators emissions from both megacities and rural areas are responsible for alarming outdoor air quality deterioration (LiuG. et al., 2020).
1.3 Aim and objectives of the study
The aim of this work is to evaluate the tailpipe emissions for natural gas and fuel petrol generator. The objectives of this study are:
- To evaluate the actual level of emissions for both petrol and natural gas fueled generator
- To determine differences in emission pollutants concentrations between petrol and natural gas.
- To make a recommendation of how pollution can be controlled.
1.4 Significance of the study
This study will serve as a means of knowing the major caused of pollution between petrol and natural gas fueled generator.
It will also serve as a means of making the reader to become familiar with the major effect of pollution on human health.
To the student involved, this study will serve as a means of becoming familiar with the major causes of air pollution and how to reduce them most especially in our industrial sector.
1.5 Scope of this study
The scope of this work covers evaluating the actual level of emissions for both petrol and natural gasfueled generator. In this work, exhaust gases (i.e. CO, CO2, NOX and HC) were randomly measured from 200 generators using the exhaust gas analyzer. Significant differences were observed in the concentrations of pollutants measured based on the generator engine capacity for both petrol and natural gas fueled generators.
CHAPTER FIVE
5.1 CONCLUSIONS AND RECOMMENDATION
Fuels are a very important source of energy in the industry. However, their use in internal combustion engines is associated with emission of pollutants through the exhaust system. The study concludes that vehicle drivers had adequate knowledge regarding the fact that generators emit some level of waste gases into the environment but a relatively fewer number of them knew the composition of the exhaust gases. In addition, most natural gas generator operators were of the view that emissions from their generators do not pollute the environment. However, quantitative measurements of concentration of exhaust gases indicated that emission from natural gas generators is lower than that of gasoline except in the case of HC emissions.
Therefore natural gas represents a good fuel alternative to petrol and therefore steps could be taken by the relevant governmental agencies to ensure standard conversion methods and kits are used by natural gas mechanics if the full environmental benefits are to be derived from the use of natural gas.
Limitations
Generators emission control is a key research carried out world wide because of the negative impact the pollutants are having on the environment. This results in the use of alternative cleaner fuels such as natural relative to the conventional petrol. In this study, natural fueled generators have a reduced pollutant concentrations. However, the study had some limitations which could influence the levels of exhaust gases determined and need to be discussed. Generators emission level is influenced by the age of a generators, condition of its engine, type, engine characteristics, generators maintenance and weight which were not considered in the study since many of the generators examined were without vital information and maintenance reports. These parameters were assumed to be the same for both natural gas and petrol generators assessed. In addition, emission level is also influenced by traffic characteristics and type of road intersections for generator is motion but this study was carried out when the generators were stationary with the engines running at idle speeds. Although generators types were considered in this study, generators were classified according to engine capacity and not necessarily the type and make. The researchers believed these factors could have some level of influence on their results but their study was worthy to have a baseline data on exhaust gases emission concentrations from both gasoline and natural gas generators.
