INVESTIGATION OF THE TRANSPORT PROFILE AND DISPERSION OF ATMOSPHERIC AEROSOL OVER THE COASTAL REGION OF LAGOS

ABSTRACT

This study investigates the transport profile and source-sink system for sea salt aerosol over the coastal region of Lagos. The study utilized the GPS information of the study locations to simulate meteorological variables over the area from the Air Resource Laboratory (ARL) website, The ARL/GFS model was used to determine the wind rose information between 8th and 14th of June, 2017. In addition, backward air mass trajectories were determined at various heights of 0m, 1000m and 2000m above ground level (AGL) for aerosol transport patterns as well as concentration dispersion using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The result showed that aerosols are of sea salt origin which evolved from the sea of the Atlantic Ocean. The maximum wind speed for the period considered from 8th to 14th June 2017 was 4 to < 7 m/s range in SW direction and as such complete calmness was not observed during the period under consideration. The highest frequency of wind blown was 56% which implies that 56% of atmospheric sea salt aerosol were
transported during the study period. The backward concentration trajectory indicated that the maximum aerosol pollution reaching Lagos was 2.1 x 10-10 mg/m3 which were from the Atlantic Ocean and the minimum was about 5.0 x 10-16 mg/m3. Since these pollutants are most likely sea salts which are highly corrosive, adequate corrosion protection is recommended.

ASSESSMENT OF THE TECHNICAL BENEFITS OF DUAL GRADIENT DRILLING

CHAPTER ONE
INTRODUCTION
DGD is a technology that makes use of separate fluids with different densities in the wellbore. The lighter fluid floats on top of the heavy fluid in the riser. The lighter fluid is only used for inducing pressure and is otherwise inactive. However the heavy fluid is used for the same purpose as used in the conventional drilling procedures. This helps to adjust the bottom hole pressure (BHP) in a shorter time, and make it able to adjust the well bore pressure curves with the formation pressure curves. The attractions that DGD highlights are the reduction in the cost of drilling and an increase in the production rate after well completion ( Gaup, 2014).
The development work on the DGD was accelerated during the 1990s when a joint industry project was undertaken with the aim to utilize such technology to be used in the high pressure, low fracture gradient in ultra-deep waters. Even though sufficient investments have been made on drilling rigs which can operate in depths greater than 8000ft, the resources present at these reservoirs cannot be extracted unless new procedures are developed to lower hydrostatic mud pressures to avoid fractures in the shallow zones. The problems faced in ultra-deep drilling include shallow water flowing, lost circulation and loss of well control. If any of these problems occur, they will prevent the completion of the well to be achieved. Multiple casing strings are used to avoid such problems. This means that the production string is quite small for a high production well and also for horizontal and multilateral completions in order to make the project economically viable. Pumps are used to reduce the hydrostatic head from the mud-line to the surface in DGD techniques. This is the reason why there is no balanced u-tube present in DGD as compared to the conventional drilling ( Kennedy 2001). The primary component that enables the DGD operations is the Mud Lift Pump (MLP). With the help of diaphragm pumps powered by the seawater, it pumps the drilling fluid and cutting back to the rig floor. The Subsea Rotating Device (SRD) maintains the boundary between the sea water density fluid in the drilling riser and the drilling fluid and redirects the mud through the MLP through the Solids Processing Unit (SPU). SPU is used to decrease the size of the drill cuttings which can be managed by the MLP (Ganpatye et al. 2013).

MODELLING, SIMULATION AND SENSITIVITY ANALYSIS OF A FATTY ACID METHYL ESTER (FAME) REACTIVE DISTILLATION (RD) PROCESS USING ASPEN PLUS

ABSTRACT

Reactive distillation, being an intensified process of combining reaction and distillation in a single vessel, is an ongoing research. This work considered the use of this novel process to investigate the esterification of a fatty acid methyl ester, an alternative fuel, biodiesel, which is a potential economic bedrock via modelling, simulation and sensitivity analysis in Aspen Plus. The selection of FAME was conducted based on the source of the oil for quality biodiesel and on its compatibility with the software; these led to the selection of oleic acid as the fatty acid of the process. A reactive distillation process for a reaction between oleic acid and methanol was then set up in the Aspen environment and tested for convergence, after a successful simulation, two operating parameters (reflux ratio and reboiler duty) were varied from 2.0-5.5 and 1350-1800 W, respectively. Afterwards, graphical representations of composition profiles, temperature profiles and sensitivities of mole-fraction to reboiler duty at different reflux ratios were obtained. Results obtained showed that a reflux ratio of 2.0 was most compatible with a reboiler duty of 1800 W to produce a methyl oleate mole fraction of 0.7627 in the bottom product. Given the novelty of this process in comparison with the conventional independent reaction and separation, more experiments should be carried out to help show any discrepancy between reality and simulation world.

DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN SOIL SAMPLES AROUND SELECTED POWER GENERATORS

CHAPTER ONE
INTRODUCTION
1.1 Background of Study
Polycyclic Aromatic Hydrocarbons refers to a large class of organic compounds which contains two or more fused aromatic rings made up of carbon and hydrogen atoms. PAHs have the following general characteristics common to them; high melting and boiling points, low vapour pressure and very low water solubility which tends to decrease with increasing molecular mass (Ahland and Mertens, 1980). Most of the PAHs with low vapour pressure in the air are adsorbed on particles. When dissolved in water or adsorbed on particulate matter, PAHs can undergo photodecomposition when exposed to ultraviolet light from solar radiation. In the atmosphere, PAHs can react with pollutants such as ozone, nitrogen oxides and sulfur dioxide, yielding diones, nitroand dinitro-PAHs, and sulfonic acids, respectively. PAHs may also be degraded by some microorganisms in the soil (WHO, 1987; USDHHS, 1994).
PAHs are important priority organic pollutants. They may be released during incomplete combustion or pyrolysis of organic matter. This is a major source of human exposure. PAHs emanate primarily as combustion products from vehicle and generator emissions, coal and oil burning plants. They are conveyed by rainfall into the aquatic
environment after being absorbed onto smoke particles settling in all kinds of surfaces. (Brookes and Lawley, 1964). Toxicological studies have shown that some of these PAHs have the potential for tetratogenesis or carcinogenesis in human beings. As a result of their highly hazardous nature, they are monitored in waste waters, soils and atmosphere. Sensitivedetection and accurate reproducible quantification of organics is very important in minimizing the health risks of PAHs. (Larsson, 1982).
PAHs are formed mainly as a result of pyrolytic processes, especially the incomplete combustion of organic materials during industrial and other human activities, such as processing of coal and crude oil, combustion of natural gas, including for heating, combustion of refuse, vehicle traffic, cooking and tobacco smoking, as well as in natural processes such as carbonization. There are several hundred PAHs; the best
known is benzo[a]pyrene (BaP). In addition a number of heterocyclic aromatic compounds (e.g. carbazole and acridine), as well as nitro-PAHs, can be generated by incomplete combustion (WHO, 1987).
The emissions of BaP into the air from several sources in the Federal Republic
of Germany in 1981 were estimated to amount to 18 tonnes: about 30% was caused by
coke production, 56% by heating with coal, 13% by motor vehicles and less than 0.5%
by the combustion of heating oil and coal-fired power generation. Other BaP sources were not taken into consideration (WHO, 1987). However, the present contributions from the different important sources, such as residential heating (coal, wood, oil), vehicle exhausts, industrial power generation, incinerators, the production of coal tar, coke and asphalt, and petroleum catalytic cracking, are very difficult to estimate. Thesefigures may also vary considerably from country to country. In the USA, the residential burning of wood is now regarded as the largest source of PAHs (USDHHS, 1994).
Stationary sources account for a high percentage of total annual PAH emissions.
However, in urban or suburban areas, mobile sources are additional major contributors to PAH release to the atmosphere (Baek et al., 1991). Atmospheric PAHs are continuously deposited to the earth by dry or wetdeposition processes. Some of these PAHs are from nearby sources, such as automotive or generators exhaust. Other PAHs are from more distant sources and have been carried various distances through the air. About 500 PAHs and related compounds have been detected in the air, but most measurements have been made on BaP. Data obtained prior to the mid-1970s may not be comparable with later data because of different sampling and analytical procedures (WHO, 1987). The natural background level of BaP may be nearly zero. In the USA in the 1970s, the annual average value of BaP in urban areaswithout coke ovens was less than 1 ng/m3 and in other cities between 1 and 5 ng/m3. In several European cities in the 1960s, the annual average concentration of BaP was higher than 100 ng/m3 (WHO, 1987). In most developed countries BaP concentrations have decreased substantially in the last 30 years. Thus PAH levels lower by a factor of 5 to 10 than those in 1976 were reported for a traffic tunnel in Baltimore and for ambient air in London in the second half of the 1980s (Baek et al., 1991). The declines were attributed to the increased use of catalytic converters in motor vehicles, a reduction in
coal and open burning with a movement to oil and natural gas as energy sources, and
improved combustion technology. PAH emissions from open burning, especially coal,
have been declining in many developed countries as a result of efforts to control smoke
emissions (Baek et al., 1991). In 1990, a German study found BaP concentrations of
below 1 ng/m3 at monitoring stations not affected by emission sources, from 1.77–3.15
ng/m3 at stations close to traffic, and 2.88–4.19 ng/m3 at stations with traffic and
additional industrial emission sources. The annual (1989-1990) average concentration
of BaP close to traffic in the Rhine-Ruhr area was reported to be 3–6 ng/m3 (Pfeffer,
1994). In Copenhagen, the mean BaP concentration (January to March 1992) at a station
in a busy street was found to be 4.4 ng/m3 (Nielsen et al., 1995).
Additional contributions from tobacco smoking and the use of unvented heating
sources can increase PAH concentrations in indoor air and, in certain cases, PAHs can
4
increase to very high levels indoors (Mumford et al., 1991 and Maroni et al., 1995).
BaP levels of 14.7 μg/m3 were found in Chinese (Xuan Wei) homes burning smoky
coal (Mumford et al., 1987). In India, the BaP concentration was reported to average
about 4 μg/m3 during cooking with biomass fuel (WHO, 1987). Very high
concentrations of BaP can occur in workplaces. Measurements using stationary
samplers or personal samplers over an 8-hour period showed average BaP
concentrations of between 22 and 37 μg/m3 on the topside of older coke oven batteries
and between 1 and 5 μg/m3 at several other worksites in the same plants. High values
have also been reported in the retort-houses of coal-gas works in the United Kingdom,
ranging from 3 μg/m3 in mask samples to more than 2 mg/m3 in peak emissions from
the retorts. In the aluminum-smelting industry, concentrations much higher than 10
μg/m3 were found at some workplaces (WHO, 1987).
1.2 Statement of Problem
Atmospheric PAHs are continuously deposited to the soil by dry or wet
deposition processes. Some of these PAHs are from nearby sources, such as generator
exhaust. The atmosphere is the most important means of PAH dispersal, it receives the
bulk of the PAHs environmental load resulting in PAHs being ubiquitous in the
environment. PAHs are emitted to the atmosphere primarily from the incomplete
combustion of organic matter. The combustion sources can be either natural or
anthropogenic. The natural sources include volcanoes and forest fires. While the
anthropogenic sources are vehicle exhaust, agricultural fires, power plants, coke plants,
steel plants, foundries and other industrial sources. PAHs tend to be found in greater
concentrations in urban environments than in rural environments because most PAH
sources are located in or near urban centers. Once released to the atmosphere, PAHs
are found in two separate phases, a vapor phase and a solid phase in which the PAHs
5
are sorbet onto particulate matter (Ravindra et al., 2008; Wang et al., 2013; Zhang and
Tao, 2009). Hydrophobic organic chemicals with low vapor pressures, such as PAHs,
are sorbet to atmospheric particulates more readily than chemicals with higher vapor of
different PAH compounds cause the individual PAHs to distribute in different
concentrations in the vapor (Kameda, 2011) and other sorbet phases (Kuo et al., 2012).
PAHs can be added to soils if fill materials contain PAHs. When PAHs are
deposited onto the earth’s surface, they can become mobile. Since the majority of PAHs
in the soil will be bound to soil particles (Masih and Teneja, 2006; Cachada et al., 2012),
the most important factors influencing PAH mobility of particulates in the subsurface
will be sorbent particle size and the pore throat size of the soils. Such pore throat can
be defined as the smallest opening found between individual grains of soil (Riccardi et
al., 2013). If particles to which PAHs are sorbet cannot move through the soil then the
movement of PAHs will be limited because they tend to remain sorbet to particles.
17 PAHs have been identified as being of greatest concern with regard to
potential exposure and adverse health effects on humans and are thus considered as a
group. The International Agency for Research on Cancer (IARC, 2010) classifies some
PAHs as known, possibly, or probably carcinogenic to humans (Group 1, 2A or 2B).
Among these are benzo[a]pyrene (Group 1), naphthalene, chrysene, benz[a] anthracene,
benzo[k]fluoranthene and benzo[b]fluoranthene (Group 2B) (IARC, 2010). Some
PAHs are well known as carcinogens, mutagens, and teratogens and therefore pose a
serious threat to the health and the well-being of humans. The most significant health
effect to be expected from inhalation exposure to PAHs is an excess risk of lung cancer
(Kim et al., 2013).
6
1.3 Aim and Objectives
The research aim and objectives are:
1.3.1. Aim
The aim of this study is to quantify the concentrations of Polycyclic Aromatic
Hydrocarbons (PAHs) in soil samples collected around selected ABUAD power
generators.
1.3.2. Objectives
The specific objectives are to:

1. extract PAHs from soil samples collected around selected ABUAD

generators using Soxhlet extraction method.

1. determine the concentration of PAHs from (i)

iii. identify control measures for PAHs deposition in soil
1.4 Scope of study
This work covers the determination of PAHs in soil samples around selected
ABUAD power generators. The PAHs in the soil samples where extracted in the
laboratory using Soxhlet extraction method. Samples where finally concentr

EFFECTS OF FORMATION DAMAGE ON OIL WELL PRODUCTIVITY

ABSTRACT

Formation damage has been a constant headache to the oil producing industries as it is considered an impairment of the permeability of petroleum bearing formation with an expensive remediation procedure. Although, the prevention of formation damage is impracticable since every single operation embarked upon in petroleum production is a potential source of damage, it could be controlled. In this project, a well was studied and BHP survey was used from BHP analysis in addition to the information of the well history and reservoir data available. The well was observed to have been damaged with a skin of 115 and a damage ratio indicating the well should have been flowing about two times its present production rate. There are two major stimulation procedures which are the hydraulic fracturing and the matrix acidization in which the latter was used in the case of the damaged well. Well 57XX had a production rate which was initially 1550bbl/day at its peak before undergoing a decline, increased to 2100bbl/day and then continued to flow at an average of 2000bbl/day before a sharp decline and subsequent gradual declination of production rate showing the effect formation damage had on the well 57XX. This in conclusion proved that the matrix acidization technique used to stimulate the well was effective as it led to an increase in the well permeability and hence, increased the oil production rate.

CHAPTER ONE/INTRODUCTION

1.1. General Background
Formation damage is generally considered as the impairment of the unseen by the inevitable, causing an unknown reduction in the unquantifiable (Petrowiki, 2015). Also, it is a condition which occurs when barriers to flow develop in the near-wellbore region to give rise to a lower than expected production rate from or injection rate into a hydrocarbon bearing reservoir rock and it requires interdisciplinary knowledge and expertise (Amaefule et al, 1988). It can also be referred to as an impairment to reservoir (reduced production) permeability caused by wellbore fluids used during drilling, completion and work over operations (Petrowiki, 2015).
Oil well productivity on the other hand, is generally considered as the ability of a reservoir to produce hydrocarbons after the well has been drilled and made ready for production. The production stage of oil is the most important stage of a well’s life because it determines if the aim of drilling such well has been achieved or not, and this can be measured by the quantity of crude oil derived or quantity of crude oil which is producible. Formation damage is one of the major causes of decrease in oil production as a result of damage to the formation by reducing its porosity and permeability which also leads to flow restrictions. Flow restrictions into the wellbore create additional pressure drops known as ‘skin’ and reduce well productivity.
Formation damage is known to occur during any stage of a well’s life; from initial exploration, through appraisal, through production and through secondary or tertiary recovery and all these have their various roles which they play in the reduction of oil well productivity. Formation damage indicators include, among others, permeability impairment, skin damage and decrease of well performance. Formation damage according to Porter (1989) is considered not necessarily reversible and what gets into the porous media does not necessarily come out. It is, therefore, better to avoid the occurrence of formation damage rather than trying to restore it. Models for formation damages which have been proven to be verified can be used to avoid or minimize it (Faruk, 2011). Carefully planned laboratory and field tests can also help in providing scientific guidance as well as develop strategies for minimizing the damage. It will, therefore, cause considerable cost for remediation and deferred production. Accurately designed experimental and analytical techniques with the modelling and simulation approaches can be used to understand the evaluation, prevention, remediation and the control of formation damage that leads to low oil productivity.
Formation damage can occur as a result of fluid/rock incompatibility; particle migration and deposition may occur as a function of the chemistry of the clay minerals and the chemical and electrochemical nature of both the natural formation fluid and the drilling fluid. Changes in the pore fluid can also induce clay swelling which in turn reduces the pore spaces in the reservoir and this is considered a form of damage to the formation as it reduces the productivity of the formation.
The occurrence of the fluid/rock incompatibility is not as a result of only swelling of the clay and particle migration and deposition. Formation damage can also occur as a result of the fluid/fluid incompatibility. The incompatibility of the introduced fluid (drilling fluid) and the reservoir pore-fluid which creates emulsion blocks can only be controlled by stimulation techniques that include pre-flush or after flush techniques. Formation damage caused by various fluids introduced into the well is remediated by careful treatment design and quality control. The departure from radial flow in a homogenous and isotropic medium can also be a cause of formation damage. A positive skin may arise from a reduction of the area available to flow and/or a departure from purely radial flow (Harper and Buller, 1986).
Formation damage also has other causes such as the mechanical deformation around a borehole or perforation tunnel, reduction of fluid pressure during production, etc. Thorough understanding of the formation damage mechanism’s stringent measures for its control and prevention, and effective and efficient treatments are the keys for optimum production strategies for oil and gas fields.
The consequences of formation damage are the reduction of the oil and gas productivity of reservoirs and noneconomic operation. Hence, once formation damage has occurred, it is necessary that proper assessment, planning and treatment will require the cooperative efforts and knowledge of the geologists, reservoir engineer and production engineer both in the field and in the laboratory. This combined effort and approach will therefore help to develop effective solutions to the damage. A wide knowledge of the mechanism of formation damage is necessary in order for the engineers and geologists to develop effective, preventive and mitigating procedures.
With recent improvements in technology, laboratory, geology and engineering, it is easier to achieve accurate measurements which can provide the necessary insights into the mechanism, prevention and effective treatment of formation damage (Amaefule et al., 1988). Confidence in formation damage prediction using models cannot be achieved without undergoing field testing as they are necessary for the verification of the models. After the verification of the model, it can then be applied for accurate simulation of the reservoir formation damage and designing effective measures for formation damage (Faruk, 2011).
Formation has varying characteristics and a formation damage model can be used to incorporate these variations into a history matching process for the characterization of reservoir systems which can also be used for accurate prediction of future performance. Recent literature surveys have had various arguments and debate about if formation damage is considered more detrimental for the vertical wells or for the horizontal ones. However, the fact still remains that in both cases, the production loss due to formation damage is significant.

COMPARATIVE ANALYSIS OF VOID FRACTION CORRELATIONS FOR HIGH VISCOSITY OIL DATA IN HORIZONTAL PIPELINE

1 INTRODUCTION
The oil and gas industry is increasingly looking towards unconventional resources like heavy oil to help satisfy world energy demand as conventional reserves are continuously depleted due to several years of production and consumption. Viscous oil hydrodynamic characteristics are different from conventional oil (light) due mainly to its physical properties .As a result of these significantly different physical properties, heavy oil is more challenging to produce and transport. The major implication of these differences is seen in the design of heavy oil systems as well as in the implementation of technologies which were mostly developed on the basis of hydrodynamic characteristics of liquid oil. High-viscosity oils are discovered and produced all around the world. High-viscosity or “heavy oil” has become one of the most important future hydrocarbon resources, with ever-increasing world energy demand and depletion of conventional oils. Almost all flow models have viscosity as an intrinsic variable. Two-phase flows are expected to exhibit significantly different behavior for higher viscosity oils. Many flow behaviors will be affected by the liquid viscosity, including droplet formation, surface waves, bubble entrainment, slug mixing zones, and even three-phase stratified flow. Furthermore, the impact of low-Reynolds-number oil flows in combination with high-Reynolds-number gas and water flows may yield new flow patterns and concomitant pressure-drop behaviors. Void fraction prediction in high viscous liquid is of great importance .This is because most existing correlations for predicting two phase flow parameters were developed based on observations from low viscosity liquid gas flows which have different hydrodynamic features compared to high viscosity liquid gas flows. Consideration of these prediction models will ensure that pressure drop is accurately predicted (Oyewole 2009)

MODELLING, SIMULATION AND CONTROL OF THE REACTIVE DISTILLATION OF BIODIESEL PRODUCTION

ABSTRACT
In this work, the production of biodiesel via reactive distillation process has been modelled and simulated with the aid of ChemCAD for both steady state and dynamics. Also, the control of the process has been carried out using MATLAB/Simulink. In order to achieve this aim, dynamics data showing the response of biodiesel mole fraction in the column bottoms (controlled variable) to a change in reboiler duty (manipulated variable) and reflux ratio (selected disturbance variable) were extracted from the ChemCAD dynamic simulation of the developed process model and used to obtain the first-order-plus-dead-time transfer function relation between biodiesel mole fraction in the column bottoms, reboiler duty and reflux ratio with the aid of MATLAB. The open loop simulation was done by applying steps to the input variables (reboiler duty and reflux ratio). Furthermore, the set-point tracking and disturbance rejection control of the system were carried out using a PID controller tuned with Zeigler- Nichols, Cohen-Coon and trial-and-error techniques. It was observed that the controller parameters obtained by Zeigler-Nichols and Cohen-Coon tuning were not able to achieve the set-point tracking control of the system, and this necessitated the use of trial-and-error technique that was used to obtain the controller parameters used to handle the system in the desired manner for set-point tracking of maintaining the mole fraction of biodiesel at 0.9. Nonetheless, Zeigler-Nichols and Cohen-Coon tuning techniques were sufficient to successfully tune the process controller to carry out the disturbance rejection of the process. However, it was observed that the performance of Cohen-Coon tuning technique was better than that of Zeigler-Nichols tuning technique in the disturbance rejection control simulation as it had lower Integral Square Error and lower Integral Absolute Error values. It has, thus, been discovered that biodiesel could be produced in high purity via reactive distillation process, and the system could be efficiently handled to behave as desired using PID control system.
 

APPLICATION OF SURFACTANTS IN TREATING OIL CONTAMINATED SOIL

ABSTRACT

The aim of this project is to remediate oil contaminated soil with the use of surfactants. During the process of remediation, the chemical/physical properties of the soil was determined before contamination to verify that the soil is fresh and doesn’t contain any contaminant after which soil contamination in the laboratory was carried out manually and the biological analysis was carried out on the contaminated soil to determine the type of bacteria acting on the soil sample followed by the use of the surfactant (bio-solve) in the remediation of the crude oil contaminated and the biological analysis was repeated to determine the rate at which the bacteria responded the addition of surfactants

CHAPTER ONE /INTRODUCTION

1.1 Crude Oil Pollution

Petroleum hydrocarbons are widespread in our environment as fuel and chemical Compounds. The uncontrolled release of petroleum hydrocarbons negatively impacts many of our soi1 and water resources. The contamination can result from leaking Underground Storage tanks (UST), petroleum refineries and bulk storage facilities, broken oil pipelines, spills of petroleum products in chemical plants and transportation processes (Sheman and Stroo, 1989). The risks of explosion and fire are also serious threats to the environment. The US. Environmental Protection Agency (EPA) has reported that there were about 1.6 million of USTs and 37,000 hazardous tanks in 1992. Approximately 320.000 USTs are leaking, and 1,000tanks are confirmed as new release each week (Cole, 1994). Approximately 200,000 USTs are in use in Canada, it leads to a considerable amount of petroleum hydrocarbon leaks and contamination in soi1 and groundwater (Scheibenbogen et al., 1994). As reported by Gruiz and Kriston (1995) an amount of 6,000,000 tons petroleum waste enter the environment each year causing serious environmental problems.
Even if the problems associated with fuel storage and distribution are solved, contamination incidental to production and commercial usage would continue to threaten ground water supplies. Many manufacturing processes necessarily produce water and sledges that are contaminated with hydrocarbons. At a typical oil refinery facility, more than 23 different waste streams have been identified, several of which have been classified a hazardous waste (Sims, 1990).
Since the contamination of soil and groundwater by uncontrolled releases of petroleum products has become a significant problem, a number of technologies have been tested to remediate the polluted sites.

1.2 Effect of The Crude Oil on the Soil

According to Cole (1994), in the US, about 16,000 sites are treated each year by the states and responsible parties treatment processes have incorporated physical, chemical, biological methods, or a combination of themRemedial action on a contaminated site can involve in situ or ex situ action. The remediation methods include excavation and landfill disposal or incineration. However, these methods are expensive and only transfer the contamination from one place to another.
According to Arora (1989) and Reed et al. (2000), soil is an unconsolidated surface material that is formed from natural bodies made up of living materials, organic and non-organic materials produced by the disintegration of rocks. Studies conducted on soils by American Society for Testing and Materials (ASTM 1994), Dorn et al. (1998), Howard (2002), Okieimen and Okieimen (2002) have focused on the effects that soil types will have within our environment when polluted with crude oil and other oily related materials. Generally, soil function at its potential in an ecosystem with respect to the maintenance of biodiversity, nutrient cycling, biomass production and water quality. When contaminated with crude oil, soil will have insufficient aeration due to the displacement of air from the spaces or pores between the soil particles. Crude oil with low-density tends to penetrate the topsoil rapidly, whereas heavier oils with higher viscosity tend to contaminate the soil more slowly resulting in greater contamination at the surface. Moreover, during the penetration process, crude oil may not change physically. However, when left in the soil for a long time and subjected to weathering it will result in cleanup difficulties. Many properties influence the behavior of crude oil mixed with soil. Viscosity of crude oil affects its rate of movement and the degree to which it will penetrate soil. Schramm (1992) has studied the measurement of oil viscosity and has used it to correlate with temperature. Like density, viscosity is affected by temperature: as temperature decreases, viscosity increases. Viscosity and the forces of attraction between crude oil and soil at the interface affect the rate at which oil will spread. Jokuty et al. (1995) noted that density and viscosity of oils shows systematic variations with temperature and degree of evaporation whereas, interfacial tensions do not show any correlation with viscosity.

1.3 Background Study

The global demand for crude petroleum has contributed to detrimental effects on surrounding ecosystems. Petroleum is predominantly made up of hydrocarbons, organic molecules that can be lethal in ecological contexts (Tang, 2011). Large tanker oil spills and other accidental discharges of petroleum have negatively impacted sea life and polluted land near the spills, creating crude oil contaminated soils (Shaw, 1992).
Many techniques have been discovered and examined for treatment and one of the most applicable methods is soil washing by surfactants. Among the soil washing methods, bio surfactants use is promising because of its efficiency for remediation of oil- contaminated soils and less environmental impacts from residue compared to surfactants (Zhang et al., 2011).

1.3.2 Surfactants

Surface-active agent are amphiphilic molecules with both hydrophilic and hydrophobic moieties, which show a wide range of properties, including the lowering of surface and interfacial tension of liquids, and the ability to form micelles and micro emulsions between two different phases. The hydrophilic moiety of a surfactant is defined as the “head”, while the hydrophobic one is referred to as the “tail” of the molecule, which generally consists of a hydrocarbon chain of varying length. Surfactants are classified as anionic, cationic, non-ionic and zwitterionic, according to the ionic charge of the hydrophilic head of the molecule (Christofi et al., 2002)
An important description of chemico-physical properties of surfactants is related to the balance between their hydrophilic and hydrophobic moieties.
Thus, surfactants can also be classified according to their Hydrophile-Lipophile Balance (HLB) (Tiehm, 1994)
The HLB value indicates whether a surfactant will produce a water-in-oil or oil-in-water emulsion: emulsifiers with a lower HLB value of 3-6 are lipophilic and promote water-in-oil emulsification, while emulsifiers with higher HLB values between 10 and 18 are more hydrophilic and promote oil-in-water emulsions (Desai and Banat, 1997).
A classification based on HLB values has been used to evaluate the suitability of different surfactants for various applications. For example, it has been reported that the most successful surfactants in washing oil-contaminated soils are those with a HLB value above 10 (Volkering et al., 1998).
As the name suggests and due to their chemico-physical structure, “surfactants” partition preferentially at the interface between phases with different degrees of polarity and hydrogen bonding such as oil/water and air/liquid interfaces. The presence of surfactant molecules at the interfaces results in a reduction of the interfacial tension of the solution.
In the presence of a non-aqueous phase liquid (NAPL), the surfactant molecules also aggregate at the liquid-liquid interface, thus reducing the interfacial tension (Volkering et al., 1998).
Another fundamental property of surfactants is the ability to form micelles, which is responsible for the excellent detergency and dispersing properties of these compounds. When dissolved in water in very low concentrations, surfactants are present as monomers. In such conditions, the hydrophobic tail, unable to form hydrogen bonding disrupts the water structure in its vicinity, thus causing an increase in the free energy of the system. At higher concentrations, when this effect is more pronounced, the free energy can be reduced by the aggregation of the surfactant molecules into micelles, where the hydrophobic tails are located in the inner part of the cluster and the hydrophilic heads are exposed to the bulk water phase. The concentration above which the formation of micelles is thermodynamically favored is called Critical Micelle Concentration (CMC) (Haigh, 1996). The number of molecules necessary to form a micelle generally varies between 50 and 100; this is defined as the aggregation number. As a general rule, the greater the hydrophobicity of the molecules in the aqueous solution, the greater is the aggregation number (Rosen, M.J. 1989). CMC is commonly used to measure the efficiency of a surface-active agent (Desai and Banat, 1997). The CMC of surfactants in aqueous solution can vary depending on several factors, such as molecule structure, temperature, presence of electrolytes and organic compounds in solution. At soil temperatures, the CMC typically varies between 0.1 and 1 mM (Volkering et al., 1998). The size of the hydrophobic region of the surfactant is particularly important for the determination of the CMC: in fact the CMC decreases with increasing hydrocarbon chain length, i.e. increasing hydrophobicity. The addition of a CH2- group to the chain has been shown to decrease the CMC by a factor of 3, according to the Traube’s rule (Fan et al., 1997)
However, anionic surfactants have higher CMCs than nonionic surfactants even when they share the same hydrophobic group. Electrolytes in solution can reduce the CMC by shielding the electrical repulsion among the hydrophilic heads of the molecules; such effect is more pronounced with anionic and cationic surfactants than with nonionic compounds (Haigh, 1996). At concentrations above the CMC, additional quantities of surfactant in solution will promote the formation of more micelles. The formation of micelles leads to a significant increase in the apparent solubility of hydrophobic organic compounds, even above their water solubility limit, as these compounds can partition into the central core of a micelle. The effect of such a process is the enhancement of mobilization of organic compounds and of their dispersion in solution (Perfumo et al., 2010.)
This effect is also achieved by the lowering of the interfacial tension between immiscible phases. In fact, this contributes to the creation of additional surfaces, thus improving the contact between different phases (Christofi and Ivshina, 2002.). The reduction effect of interfacial tension is particularly relevant when the pollutant is present in soil as a non-aqueous phase liquid.
In summary, the main surfactant- mediated mechanisms, which may potentially enhance hydrophobic organic compound remediation, include the reduction of interfacial tension, Micellar solubilization and phase transfer between soil particles and the pseudo-aqueous phase.

1.3.3 Critical micelles concentration

When there is a large concentration of surfactant solution in water there may not be enough area at the water surface for all the surfactant molecules to gather, then the surfactant will begin to cluster together in clumps called micelles. The concentration at which micelles first begin to form is known as the critical micelle concentration (CMC).
Many physical properties depend on surfactant CMC. As surfactant activities are best described in aqueous solutions, their CMC depends on temperature, surfactant chemical structure and ionic characteristics. The surfactants behavior can be explained at concentrations below and above CMC. Holmberg (2002), Elvers et al. (1994) and Rosen (1989) made the following observations about surfactant CMC dependence on chemical structures:

•  As the hydrocarbon alkyl group increases, surfactant CMC increases. Depending on the alkyl length the CMC of non-ionic surfactants are about two folds less than that of the ionic surfactants. However, the cationic surfactants have a higher CMC than the anionic ones.
•  Increase in temperature decreases the CMC of some non-ionic surfactants whereas the solubility of ionic surfactants increases.
•  Salt addition reduces the CMC of ionic surfactant while those of non-ionic are slightly affected.
•  The temperature at which the solubility value of anionic surfactants equals the CMC is known as the Kraft point.
•  The temperature at which cloud occur for the non-ionic surfactant solutions is known as cloud point.

PREDICTION OF STUCK PIPE USING ARTIFICIAL NEURAL NETWORK: A CASE STUDY ON NIGER DELTA FIELDS OF NIGERIA

ABSTRACT
Drilling is a process that involves the procurement of natural resources such as oil and gas which holds prime importance in today’s world, Drilling practices abounds with a number of complications and an efficient way of dealing with such problems is key to the continuity of the process.
One of such problems is stuck pipe, stuck pipe is a common problem in the industry and it accounts for major rig time loss known as Non Productive Time (NPT) and also accounts for billions of dollars wasted annually in the petroleum industry.
The purpose of this project to implement a powerful machine learning tool known as the Artificial Neural Network in the prediction of stuck pipe using Niger Delta fields as a case study,
The ANN is a Matlab built in function and computational system inspired by the structure, processing method and learning ability of the human brain.
The ANN has the ability to take multiple inputs ( plastic viscosity, yield point and gel strength at 10 seconds and 10 minutes), a target ( mud weight ) to produce a single output which is the prediction of the occurrence of stuck pipe. This was successfully carried in this research study. It is therefore shown in this study that the ANN can be successfully used to predict the occurrence of stuck pipe. Thus, they can be utilized with real-time data representing the results on a log viewer which can help reduce the occurrence of getting stuck while drilling and all the complications that comes with this occurrence.

EFFECT OF FOAMING AGENTS ON CRUDE OIL SYSTEM

ABSTRACT

This report entails the study of the effect of the foaming agents in the physio-chemical properties of the oil system, this report investigate if the addition of such foaming agents can improve production and also determines the properties of the crude oil and the foaming agents used. The properties investigated are Density, Specific Gravity, API gravity, viscosity, Surface Tension and Pour point before and after the addition of the foaming agents. The effects of foaming agents in crude oil: it increases density, viscosity and specific gravity of crude oil and decreases API gravity, surface tension, pour and cloud point of crude oil.
Statistical and graphical analysis were used to interpret the results of the experiments carried out. The results show that foaming agents increases oil density, oil viscosity, oil specific gravity and decreases oil API gravity, oil surface tension, oil cloud point and pour point.
The study would help petroleum engineers to understand the positive impact of foams in oil; especially during enhanced oil recovery (EOR).With such understanding and putting it into practical, production will be maximized.