By: Suliman Alamin Abd Elmagid A thesis Submitted in Fulfilment of the Requirement for the ...

97 Pages·2004·1.45 MB·English

SD9900003
P
By:
Suliman Alamin Abd Elmagid
A thesis Submitted in Fulfilment of the Requirement
for the Degree of Master of Science
in Physics
Department of Physics
Faculty of Education
University of Khartoum
June, 1996
We regret that
some of the pages
in this report may
not be up to the
proper legibility
standards, even
though the best
possible copy was
used for scanning
CONTENTS
Page
ACKNOWLEDGEMENTS I
ABSTRACT II
CHAPTER ONE 1
ENVIRONMENTAL POLLUTION 1
1.1: Introduction 1
1.2: Natrual Environment 2
1.3: The Economic of Environment 2
1.4: Environmental Health and Pollution 2
1.5: Main Sources of Pollution 3
'• ' I.APTER TWO 6
X-RAY FLUORESCENCE 6
2.1: Introduction 6
2.2: X-Ray Photon Interaction with Matter 6
2.2.1: The Mass Attenuation Coefficient , 7
2.2.2: The Photoelectric Effect 8
2.2.3: The Compton Scattering 9
2.2.4: The Ralicgh Scattering 10
2.2.5: Auger Effect 10
2.3: Characteristic Lines and Selection Rules ". 11
2.4: Fluorescence Yield 12
2.5: The Fundamental Relation between the Intensity and
the Concentration 12
C11APTER THREE 16
INSTRUMENTATION 16
3.1: Introduction 16
3.2: The Pressing Machine 16
3.3: The X-Ray Spectrometer 17
3.4: X-Ray Sources 19
3.4.1: The Radioisotope Sources 19
3.5: The Si (Li) Detector 20
3.6: Electronics 21
3.6.1: The Preamplifier 21
3.6.2: The Amplifier 22
3.6.3: The Multichannel Analyzer 23
' ! 1APTI-R FOUR 24
EXPERIMENTAL MEASUREMENT 24
4.1: Introduction 24
4.2: The Study Area 25
4.3: Measurements Using XRF 26
4.4: Calibration 27
4.5: XRF Software 28
CIIAPTER FIVE 29
RESULTS AND DISCUSSION , 29
CHAPTER SIX ". 36
CONCLUSIONS 36
APPENDIX 40
REFERENCES 50
ACKNOWLEDGEMENTS
I would like to express my sincere gratitude and appreciation
to Dr. Farouk llabbani for his supervision, encouragement and
guidance throughout this work.
My deep gratitude and particular thanks are recorded to
University of Kordofan for support and assistance with a
scholarship. My gratitude is also extended to the Department of
Physics, Faculty of Education and to the Physics
Department^ acuity of Science , University of Khartoum
especially the staff of the Applied Nuclear Sciences Laboratory, for
help during this work.
ABSTRACT
In the present work an attempt has been made for the
analysis of some soil, plant, sediments and fish samples of
relevance to environmental pollution in Khartoum area.
These samples have been collected from different places in
Khartoum area, so *k% cover industrial areas, agricultural and
residential areas , as well as Tuti Island as control area.
Special attention has been dedicated to the analysis of lead
concentrations resulting from automobile-emissions in soils and to
other toxic mctnls such ns Cr in some industries.
The samples were analysed by X"rav fluorescence (XRF)
technique. The results obtained using XRF measurements and
computer software called QXAS for data analysis.
The concentrations of lead and some heavy metals such as
Cr in soils from certain locations were alarming and may create
pollution problems in the near future.
The results obtained in this study were compared with those
obtained from different countries. The results are generally lower
than the international limits.
II
i 41 n^ A ^n\ \A £JA I^»O> aJ
l al_xijAyi J»_J . ijj^£ul (JA AjJLa. 4JUaxa (_pAJ ^' ^£ *b J}J^~ ^"-
^ '«j *- j^ 7- ^ l-i i ill yi '' ^ 'J' " QJ\I.*I aj
. (QXAS) J>JX&\ 2-»IJJ^
> Jai <
III
CHAPTER. ONE
ENVIRONMENTAL POLLUTION
1.1-INTRODUCTION:
The contribution to environmental pollution of heavy metals
from agricultural , industrial processes and automobile emsisson
has been the subject of intensive investigations in recent years .
This study has been conducted .. to investigate various
sources of pollution in Khartoum area using theX-ray fluorescence
(XRF) technique . The aim was to perform and establish some data
for possible sources of pollution . The investigations included
studies of pollution for lead resulting from automobile emissions ,
toxic metals in some industries and heavy metakpollution in plants
, sediments and fish from differnt areas along White Nile , El
Bageir industrial area , Bahri industrial area and tanneries in
Khartoum area .
1.2: NATURAL ENVIRONMENT :
To understand the environment we have to make a positive
approach and carry out objective studies and analysis of the
components that act collectively to create different sets of
environmental conditions .
The fundamental factors that determine the environment of a
region arc its physical characteristics such as (a) Lithology (b)
Natural vegetation, (c) Morphology , erosion , maturity of surface
(d) Fauna , particularly information on distribution and
concentration of such insectpests that influence the economic
activities of man , (e) Soil (f) Surface or ground water .
The natural environment has been utilized by human Society
for establishing its habitations and pursuing its economic activities
Increasing, pressure of population and demands of higher
standards of living on food \ comfortfbalance of nature . [1]
1.3: THE ECONOMICS OF ENVIRONMENT :
The economics of environment can be divided into two
catogeries . The first involves the development of new processes of
consumption and production ( integrated conservation
technologies) as a long term solution . Production processes
concentrate on clean production and use of energy , recycling , and
the use of natural re-usable raw materials. The second category
involves the use of political and legal measures to reduce the
environmental pollution causedfsuch activities . [2]
1 A: ENVIRONMENTAL HEALTH AND POLLUTIONS :
Rapid industrial development and the growth of cities and
increase of traffic through - out the world led to the recognition of
the interrelation between environmental pollution and public health
. The main sources of pollution are air , water , land . [3]
Pollution is an undesirable change in the physical, chemical
and biological characteristics of our air , land and water , that may
harmfully affect human life or that of desirable living species.
Pollution may waste or deteriorate our raw material resources .
The human race is increasingly exposed to pollution of the
air , water, land , soil and various physical hazard associated with
urban life and work . The hazards to human health from such
exposure have become of great concern to scientists and public
health administrations .[4]
Two types of pollutants were identified :-
(a) Non - degradable pollutants e.g . lead , and other toxic metals ,
etc
(b) Biodegradable pollutants such as municipal sewage that can be
decomposed either by natural processes or in special engineering
systems (e.g: municipal treatment plants ).
The environmental pollution has become an extremely
serious problem for the industrialized world in particular and also
to developing and poor countries .
t .5: MAIN SOURCES OF POLLUTION :-
Main sources of pollution are : air, water and land . These
various sources of pollution are summarized below . [5]
A-Air Pollution :-
Air pollution is a serious source of pollution which is
defined as the release of waste gases from biological, chemical or
physical processes which contains substances harmful to human
life and comfort. Elements of air pollution are :