Effect of two Corexit dispersants in the removal of Arabian light and heavy crude oils from seawater surface

In this study, ZnO nanoparticles were modified with rice bran. Synthesis and production of ZnO nano-particles is highly important due to the use of rice bran. In addition, XRD and SEM analyses were used to ensure the production quality of the nano-particles. The images clearly showed surface uniformity of the synthesized organic ZnO nano-particles. Afterward, the modified nano-particles were injected into crude oil in different weight percentages according to their properties (heavy and light crude oil). The injection was done at a temperature range of 30–150 °C with operating pressures varying from 10 bar to 300 bar. The adhesion force created between heavy or light crude oil molecules and organic ZnO nano-particles was modified with rice bran. Furthermore, an increase in the operating temperature increased the thermal conductivity of oil samples from 0.21 to 2.54 W/m °C for the light crude oil sample and 1.56–6.3 W/m °C for the heavy crude oil sample. The results showed that the percentage of the asphaltene precipitation decreased with the increased API of the crude oil. In addition, the percentage of asphaltene precipitation for nano-light and heavy crude oil was considerably better than the simple light and heavy crude oil samples, respectively. The nano-particles improved the crude oil recovery from reservoirs. The results indicate that the probability of asphaltene precipitation in the case of light crude oil nano-particles is less than the simple light crude oil by 28.3%. This is 8.1% for the heavy crude oil compared to the simple heavy crude oil.

Rheological properties of heavy & light crude oil mixtures for improving flowability

Canadian reserves of heavy gravity crude oil are vast and the potential producibility from those reserves are expected to be surplus to Canadian requirements into the 1990's. This paper focuses on the impact that market constraints may have on the future supply of heavy gravity crude oils from the Western Canadian basin. It observes that severe export restrictions will not only limit the orderly development of available reserves in the area but will also impair the prospects of additional enhanced recovery of conventional heavy crude reserves and restrict future experimental applications of oil sands recovery in the Cold Lake deposit of Alberta. Since it is expected that export restrictions for heavy gravity crude oil will be lifted in the future the outlook for expanded development of indigenous reserves is promising. Introduction Heavy crude oil, as presently produced in the western Canadian basin, is generally distinguished from other light and medium crude oil production in the same basin by its low API gravity. For purposes of this paper the authors assume that all crude oil streams with an average API gravity of 25 ° or less are heavy crude oil. Within this general classification further sub-division can be identified:Lloydminster type crude oil which is conventional production of heavy crude oil with API gravity ranging from 12 to 17 °,other heavy crude oil from conventional production ranging in API gravity from 17 to 25 °, andnon-conventional heavy crude oil largely occurring as bitumen with a specific gravity of less than 12 ° API. This last group would include all available production from experimental oil sands extraction schemes in Alberta. In Alberta, Lloydminster type crude oil is considered to be that produced from an area between Townships 43 and 53, Ranges 1 to 7, West of the Fourth Meridian, inclusive, and only from those pools within that area characterized by high viscosity oil and unconsolidated sand reservoirs. Other conventional heavy crude oil is that classified as heavy crude in the Energy Resources Conservation Board (ERCB) Report 76–181, exclusive of the Lloydminster type. In Saskatchewan, oil from pools served by the Husky pipeline and Murphy pipeline systems (Sask. Area 1) is categorized as Lloydminster type heavy crude oil. Oil from pools constituting the Bow River pipeline (Sask. Area II) and the South Saskatchewan pipeline (Sask. Area III) streams is considered to be of the other heavy crude oil type. Consistent with our definition of heavy crude oil, production from the pools comprising the West spur Pipeline stream (Sask. Area IV) is excluded since the authors consider it to be of the light and medium variety. The oil sands experimental heavy crude oil is that expected to be recovered from experimental projects in the Cold Lake region of Alberta. These heavy crude oil producing regions are shown on Figure 1.

Unlike conventional oil production methods, enhanced oil recovery (EOR) processes can recover most oil products from the reservoir. One method, known as wettability alteration, changes the hydrophilicity of the reservoir rock via decreased surface interactions with crude oils. The mitigation of these attractive forces enhances petroleum extraction and increases the accessibility of previously inaccessible rock deposits. In this work, silica nanoparticles (NPs) have been used to alter the wettability of two sandstone surfaces, Berea and Boise. Changes in wettability were assessed by measuring the contact angle and interfacial tension of different systems. The silica NPs were suspended in brine and a combined solution of brine and the Tween®20 nonionic surfactant at concentrations of 0, 0.001, and 0.01 wt% NP with both light and heavy crude oil. The stability of the different nanofluids was characterized by the size, zeta potential, and sedimentation of the particles in suspension. Unlike the NPs, the surfactant had a greater effect on the interfacial tension by influencing the liquid-liquid interactions. The introduction of the surfactant decreased the interfacial tension by 57 and 43% for light and heavy crude oil samples, respectively. Imaging and measurements of the contact angle were used to assess the surface-liquid interactions and to characterize the wettability of the different systems. The images reflect that the contact angle increased with the addition of NPs for both sandstone and oil types. The contact angle in the light crude oil sample was most affected by the addition of 0.001 wt% NP, which altered both sandstones’ wettability. Increases in contact angle approached 101.6% between 0 and 0.001 wt% NPs with light oil on the Berea sandstone. The contact angle however remained relatively unaffected by addition of higher NP concentrations, thus indicating that low NP concentrations can effectively be used for enhancing crude oil recovery. While the contact angle of the light crude oil plateaued, the heavy crude oil continued to increase with an increase in NP concentration; therefore indicating that a maximum contact angle in heavy crude oil was not yet achieved. The introduction of NPs in light and heavy crude oil samples altered both the Berea and Boise sandstone systems’ wettability, which in turn indicated the efficacy of the silica NPs and surfactants in generating a more water-wet reservoir. Consequently, silica NPs and surfactants are most promising for EOR across the range of oil types.

The efficiency of attapulgite liners as anti-seepage for crude oil is examined. Consideration is given to the potential use of raw attapulgite and mixture attapulgite with prairie hay and coconut husk as liners to prevent crude oil seepage. Attapulgite clay used in this study was brought from Injana formation /Western Desert of Iraq. Two types of Crude oil brought from Iraqi oil fields were used in experiments; heavy crude oil from East-Baghdad oil field and light crude oil from Nassiriya oil field. Initially the basic properties of attapulgite and crude oils were determined. The attapulgite clay was subjected to mineralogical, chemical and scanning electron microscope analyses. Raw Attapulgite 150µm, 75µm, and 53µm were tested as anti-seepage liners for heavy and light crude oil. Experiments showed that raw attapulgite liners 53µm and 75µm are good in terms of retention and prevention of seepage so they can be used as the main layer to impede the flow of heavy crude oil. Raw attapulgite150µm could not be used as a liner to impede the flow of crude oil. This type of liner is totally inefficient for heavy and light crude oil. Adding prairie hay to attapulgite 150µm gives a good barrier medium that retains heavy crude oil and prevents it from seepage as long as possible. Raw attapulgite liners failed to prevent light crude oil seepage whereas the partial substitution of attapulgite by prairie hay or coconut enhanced the performance of the liner. Moreover, the addition of prairie hay with coconut to attapulgite enhanced the performance of the liner to a greater extent compared to raw attapulgite liners and mixture liner attapulgite with prairie hay.

Compatibility and rheology of bio-oil blends with light and heavy crude oils

In situ combustion and high-pressure air injection are enhanced oil recovery (EOR) processes used to recover oil from both heavy and light oil reservoirs. These processes are quite complex and involve consideration of heat and mass transfer, phase behaviour of oil, water and gas, as well as relative permeability effects. This paper outlines a study that was conducted in order to develop a better understanding of the heats of combustion (HOC) for three different types of crude oils and their respective saturate, aromatic, resin and asphaltene (SARA) fractions. One outcome of the study indicated that saturates and aromatics have higher heating values than resins and asphaltenes, where this value in both saturates and aromatics (in any given crude oil) is close. Resins and asphaltenes also displayed heating values that were almost the same, however, were consistent in having a lower heating value than saturates and aromatics. The linear mixing rule was applied to predict the heat of combustion for the three crude oils studied. The HOCs for the maltene and asphaltene fractions were mathematically combined (per the mixing rule) to predict the actual observed HOC of the combined maltene/asphaltene crude. This rule did not hold true for all the crude oils studied, however, which suggests that the heat of combustion is not necessarily independent of the presence of other fractions. Introduction In situ combustion and high pressure air injection are technologies used for the recovery of both heavy and light crude oils. These technologies involve the creation of an oxidation front in the reservoir with subsequent propagation by air injection. Generally, air is injected in the reservoir and the oxygen contained in the air reacts with the oil through various oxidation reactions. The burning front is formed and the combustion gases produced from these reactions are available to help displace the oil. This process offers economic and technical opportunities for improved oil recovery in many reservoirs. Many thermal analysis studies on both light and heavy crude oils have been conducted and several oxidation tests for modelling the process have been performed. Verkoczy and Freitag(1) applied the relevance of various oxidation reactions to the modelling of in situ combustion in heavy oils, through three different sets of experiments. They performed thermogravimetric scans and autoclave tests on three heavy oils and their SARA fractions. They found that low temperature oxidation had significant and sometimes dramatic effects on the amount of coke formation. They also found that asphaltenes apparently underwent low temperature oxidation more rapidly than other crude fractions. K?k et al.(2) used thermogravimetric analysis under an air atmosphere at a 10 °C/min heating rate. Two oils (medium and heavy) were separated into their SARA fractions. Then a quantitative investigation was performed in order to determine the temperature intervals at which evaporation, oxidation and combustion effects operated for each fraction. Kinetic parameters of SARA fractions according to the Coat and Redfern technique were also established. K?k and Karacan(3) studied the behaviour and effect of SARA fractions of two different oils during combustion using a thermogravimetric analyzer and a differential scanning calorimeter.

One of the most widelyused plastics in the world’srapidlyurbanizing population is polyethylene (PE). Globally, there is a growingdemand for plastics. Polyethylene plastics do pollute and harm theenvironment. Although polyethylene is said to be nonbiodegradable,any chemical deterioration can take hundreds of years. This studyintends to improve the crude oil property, precisely its pour point,by using polyethylene derived from waste products with magnetic nanoparticles(MNPs) and applying it to heavy and light crude oils. Forty crudeoil samples were prepared by changing the PE additive concentrationfrom 0.25 to 2% with 0–2.0% MNP concentration. Dynamic lightscattering (DLS), gas chromatography, and photomicrographic techniqueswere employed during the study. DLS results revealed that nanoparticlesof heavy (B) crude oil have bigger particle sizes than light (A) crudeoil samples, and the overall distribution of the added nanoparticleswas much better in light crude oil than in heavy crude oil. The photomicrographicresults revealed that the treated samples using additives provideda significant wax crystal reduction compatible with the provided pourpoint results. The prepared sample of the treated light (A) crudeoil provided a more extraordinary rheology performance than the heavy(B) crude oil. Moreover, prepared crude oil samples with PE additivesand MNPs are effective as pour point depressants.

This paper provides estimates of "in place" and recoverable conventional light and heavy crude oil resources for the Western Canada Sedimentary Basin. Components of the oil resource base considered are currently established reserves, resources available through infill drilling and the application of enhanced recovery techniques in currently established pools, extensions to these pools and new pools, which available geological and statistical information indicates could reasonably be expected to be discovered in the future. The Geological Survey of Canada (GSC) last made an estimate of Western Canadian conventional light crude oil resources in 1988(1). Estimates of conventional heavy crude oil resources have been previously reported in the reports "Canadian Energy Supply and Demand" prepared by staff of the National Energy Board (NEB)(2, 3). Recently, techno logical progress, and in particular 'the application of horizontal drilling, has, led, to the potential for significant improvements in recovery efficiencies for conventional oil. This paper reviews and updates the previous resource assessments by NEB staff in light of the recent technological advances. Introduction The Western Canada Sedimentary Basin (WCSB) occupies an area of 1.4 million square kilometres of southwestern Manitoba, southern Saskatchewan, Alberta, northeastern British Columbia and the southwest corner of the Northwest Territories (Figure 1). Petroleum resources of the basin range from natural gas at the light end of the spectrum through conventional crude oil to bitumen, 'which is also referred to as unconventional oil. Conventional crude oil is that portion of this spectrum which exists in the reservoir in the liquid state and is sufficiently fluid that it flows naturally from the reservoir into a well bore. We adopt the light and heavy conventional crude oil categories of the provincial agencies but classify as light crude oil that designated as medium by the Alberta Energy and Utilities Board (AEUB), and classify as heavy crude oil that designated as medium by the Saskatchewan Department of Energy and Mines. Costs of extraction and crude oil prices are important determinants in the assessment of recoverable crude oil resources(4). However, 'we avoid focussing on the economic aspects of crude oil recovery by assuming a high crude oil price, in the order of $35(Cdn.) per barrel, so that estimates of recoverable resources are not constrained by price considerations. The assessment uses historical data based on definitions for reserves and resources that have been traditionally used by the NEB and the provincial agencies. These definitions differ from those given in the monograph recently published by The etroleum Society(5). FIGURE 1 Available In Full Paper. Categories of Resources We define the conventional crude oil resource base of the WCSB as the volume of conventional crude oil originally in place in the basin before any production. This crude oil resource base can be divided into discovered and undiscovered resources(Figure 2). Discovered resources are that part of the resource base that has been proven by drilling, testing or production.

Rheological comparison of light and heavy crude oils

One of the main challenges associated with the production of heavy or extra-heavy crude oil is transportation of the oil by pipelines, particularly without the prior reduction of the oil viscosity to acceptable values to ensure oil fluidity in the pipelines. The reduction of viscosity can be obtained by various sophisticated methods. In this study, we investigated different blending techniques to reduce the viscosity of heavy crude oil. The blending of Middle East heavy crude oil with light crude oil or with one of its distillates, such as kerosene or diesel, as diluents was conducted over the entire range of weight fractions at 20 °C and atmospheric pressure. The heavy oil viscosity was decreased from 4000 to 500 cP, representing an 88% reduction. The experimental data were fitted with an empirical equation, and the results were satisfactory, with an average absolute value of the deviation of 0.0015 cP. A negative performance of the heavy oil with diluent mixtures was identified based on the asphaltene precipitation phenomenon, which was found to depend on not only the type and composition of the diluents used but also the concentration of each diluent. To obtain additional insight into asphaltene precipitation, qualitative studies were performed with scanning electron microscopy imaging and dynamic light scattering. Compared to the other diluents, kerosene distillates performed well with a specific heavy crude oil sample under our testing conditions. The addition of 0.5–2 wt % of a solvent mixture of polar protic hexane-1-ol and nonpolar toluene to the crude oil and diluent mixture was found to successfully delay the precipitation of asphaltene in these low-viscosity mixtures.

The both of light and heavy crude oil are listed as valuable fuels. Investigation of physical properties of crude oil is so important in the well or in the enhanced oil recovery problems. The enhanced oil recovery which is named as E.O.R. is evaluated by many researchers. The Finding the properties of crude oil after addition of nano particle is considered in this work. Experiments are held to investigate the effect of nano particles on the physical properties of two kinds of heavy crude oil (API =21.45) and light crude oil (API= 32.95). Nano zinc oxide with the range of 75-89 nm in diameter is added in crude oil and changes in recovery%, is surveyed with various temperature and pressure. Experimental results are shown in Figures indicate on the positive effect of nano particles in the oil sweetening processes.

In this article, the potential use of silica and alumina polyacrylamide to inhibit wax crystallization and deposition of real crude oils has been studied for the first time. The performance of nanocomposites on a light and heavy crude oil was evaluated using cold finger apparatus, differential scanning calorimeter (DSC), polarizing microscopy, and rheometer. Nanocomposites effectively reduce wax deposition with 79% and 70% maximum efficiency for heavy and light oil, respectively. The flowability of treated heavy oil was improved, while a less pronounced effect was observed for treated light oil. DSC measurements indicated nanocomposites to delay the wax crystallization onset of heavy oil more noticeable than light oil. Polarized microscopy showed a visible morphological change, as the introduction of nanocomposites caused regular roundly shaped and finely dispersed wax crystals for both light and heavy crude oils. The results indicate that the presence of nanocomposites delays the wax crystallization process by presenting multiple spherical nucleation templates, influencing the wax crystal interactions, and preventing the formation of stable wax networks in agreement with the percolation theory predictions. The better inhibition effect of nanocomposites for heavy oil may result from two mechanisms. First, the well-dispersed nanocomposites act as nucleation centers for wax crystals. Second, asphaltene adsorption on the nanocomposite surface may prevent the formation of the asphaltene-wax three-dimensional network and delays wax crystallization. This research indicates the possibility of using silica and alumina polyacrylamide as an effective chemical agent for the inhibition of wax deposition of crude oil.

Introduction IN OCTOBER, 1976, the National Energy Board ("NEB" or "the Board") held its third public hearing inquiring into matters related to the supply of and requirements for indigenous crude oil and equivalent. One of the important aspects of the hearing was the position taken by many submittors regarding the development potential and markets for heavy crude oil. It was argued that the regulated reduction of crude oil and equivalent exports has severely restricted the market opportunities and the development of heavy crude oil. Among the reasons advanced for special treatment of heavy crude oil were:Canadian heavy crude oil differs significantly from light crude oil in quality, refining characteristics, markets served and production circumstances;there are proportionately greater prospects for increasing the current production levels of heavy than light crude oil;additions to heavy crude oil reserves and producibility could add substantially to Canada's self-reliance in oil;experimentation with enhanced oil recovery would proceed faster with assured marketability of heavy crude oil;Canada's balance-of-payments position would be improved with larger exports of heavy crude oil and greater domestic use of developed resources. The NEB, for the most part, accepted these arguments and, commencing on January 1, 1977, began on an interim basis to license for export monthly all heavy oil production surplus to Canadian requirements. The Board's complete findings were made public in a report released in February, 1977(1). Among the findings was a decision to continue the export of heavy crude oil surplus to current domestic needs provided that forecast supply exceeded forecast requirements for a period of 10 years. Overview of Crude Oil Supply Before discussing heavy crude oil supply, let us first put this resource in perspective by reviewing the over-all crude oil supply situation and previous Board decisions regarding crude oil exports. During the 1960's, crude oil reserves were being established at a rate far exceeding Canadian requirements. Annual reserves additions exceeded crude oil production each year, as shown on Figure 1. As these reserves additions were developed and the appropriate production and transportation facilities put into place, Canada's net dependence on imports was gradually eliminated. Increased access to United States markets led to a five-fold increase in exports of crude oil during the ten-year period preceding 1970. The historical plot of total Canadian production and consumption(2), presented here as Figure 2, demonstrates this gradual change in our balance of trade in liquid petroleum. However, at the same time that our domestic crude oil supply and requirements were coming into balance (ca. 1970), annual reserves additions began declining rapidly. Although there were hopes in many quarters that another big exploration play was just around the corner, as time passed it became increasingly evident that additional major oil discoveries in the conventional areas in Western Canada were unlikely. In December, 1972, the NEB released a report(3) entitled "Potential Limitations of Canadian Petroleum Supplies."

Aggregation of asphaltenes remains a scientific challenge. In the present contribution, at first, transverse magnetization relaxation (T2) data from low-field NMR measurements of the asphaltenes from heavy, medium-heavy, or light crude oil samples were recovered. Following this, diffusion ordered spectroscopy nuclear magnetic resonance (NMR) spectra of these asphaltenes were acquired to obtain average molecular weights (M w) of asphaltene aggregates. Analyzing the relaxation and diffusion behavior of asphaltene aggregates as a function of solution percentage and hence molecular weights are utilized to explain the difference between light, medium-heavy and heavy crude oil asphaltenes in aggregate formation. The main results suggest that light crude oil asphaltenes form a small but significant number of aggregates. In contrast, heavy crude oil asphaltenes demonstrate a more complicated picture at high concentrations with small, medium, and large aggregates. The relaxation behavior of medium-heavy asphaltenes is similar to those of heavy crude oil asphaltenes in diluted solutions and similar to light crude oil asphaltenes in concentrated solutions. Diffusion NMR results showed that the light crude oil asphaltene samples have a relatively smaller aggregate size, higher diffusion coefficient, and hence a smaller molecular weight than the samples extracted from heavy crude oils.