Determination of the Thermal Efficiency of Pre-boilover Burning of a Slick of Oil on Water

The burning rate of a slick of oil on a water bed is calculated by a simple expression derived from a one-dimensional heat conduction equation. Heat feedback from the flame to the surface is assumed to be a constant fraction of the total energy released by the combustion reaction. The constant fraction (χ) is named the burning efficiency and represents an important tool in assessing the potential of in situ burning as a counter-measure to an oil-spill. The total heat release, as a function of the pool diameter, is obtained from an existing correlation. It is assumed that radiative heat is absorbed close to the fuel surface, that conduction is the dominant mode of heat transfer in the liquid phase and that the fuel boiling temperature remains constant. By matching the characteristic thermal penetration length scale for the fuel/water system and an equivalent single layer system, a combined thermal diffusivity can be calculated and used to obtain an analytical solution for the burning rate. Theoretical expressions were correlated with crude oil and heating oil, for a number of pool diameters and initial fuel layer thickness. Experiments were also conducted with emulsified and weathered crude oil. The simple analytical expression describes well the effects of pool diameter and initial fuel layer thickness permitting a better observation of the effects of weathering, emulsification and net heat feedback to the fuel surface. Experiments showed that only a small fraction of the heat released by the flame is retained by the fuel layer and water bed (of the order of 1%). The effect of weathering on the burning rate decreases with the weathering period and that emulsification results in a linear decrease of the burning rate with water content.     

Estimating Time Windows for Burning Oil at Sea: Processes and Factors

This paper discusses processes and factors for estimating time period windows of in situ burning of spilled oil at sea. Time-periods of in situ burning of Alaska North Slope (ANS) crude oil are estimated using available data. Three crucial steps are identified. The First Step is to determine the time it takes for the evaporative loss to reach the known or established limitation for evaporation and compare this time-period with estimated time of ignition at the ambient wind and sea temperatures. The Second Step is to determine the water up-take of the spilled oil and compare it with the known or established limitation for water-in-oil content. The Third Step is to determine the necessary heat load from the igniter to bring the surface temperature of the spilled oil to its flash point temperature so that it will burn at the estimated time period for ignition of the slick.     

The effect of biodiesel on the rate of removal and weathering characteristics of crude oil within artificial sand columns

The physical and chemical properties of crude oils differ greatly, and these properties change significantly once oil is spilled into the marine environment as a result of a number of weathering processes. Quantitative information on the weathering of spilled crude is a fundamental requirement for a fuller understanding of the fate and behaviour of oil in the environment. Additionally, such data are also essential for estimating windows-of-opportunities, where specific response methods, technologies, equipment or products are most effective in clean-up operations. In this study, the effects of a relatively low toxicity compound, biodiesel (rape seed oil methyl ester) on the rate of removal and weathering characteristics of crude oil within artificial sand columns are thoroughly investigated using GC/MS techniques. In the absence of the biodiesel, the crude oil exhibits low mobility and a slow rate of microbial degradation within the sediment and as a result, a high degree of persistance. Brent crude oil was subject to a progressive loss of the low molecular weight n-alkanes with respect to time through evaporation and a preferential migration of these fractions through the sediment to depth. The addition of the biodiesel led to greater recovery of oil from the sediment if applied to relatively unweathered crude oil. This was as the result of the crude oil dissolving within the more mobile biodiesel. The negligible concentration of the n-C₁₀ to n-C₂₁ fraction in surface sediment samples suggests a greater solubility of these fractions within the biodiesel and that their subsequent adsorption onto subsurface sediment particles was responsible for their absence from water flushed through the sands. These results suggest that biodiesel may have an active role in the beach clean-up of spilt crude oil.     

Ignition,flame spread and mass burning characteristics of liquid fuels on a water bed

An experimental technique has been developed to study systematically the ignition, flame spread and mass burning characteristics of liquid fuels spilled on a water bed. The final objective of this work is to provide a tool that will serve to assess a fuel's ease of ignition, spread and sustaining a flame, thus, helping to better define the combustion parameters that affect in situ burning of oil spills.     

Agents Which Promote and Stabilize Water-in-Oil Emulsions

A number of research groups have investigated the formation and stabilization of water-in-oil emulsions. A variety of compounds and mixtures have been shown to promote and stabilize these emulsions, including sea water particulates, as well as fractions or compounds found in crude oil. Asphaltenes, resins and waxes in crude oil contribute to the formation of stable oil-in-water emulsions. Within the asphaltene fraction, the nickel porphyrins appear to play an essential role in emulsion formation. The vanadium porphyrins, although more abundant than nickel porphyrins in most crude oils, do not play an important role in emulsion formation, possibly because of their higher polarity. It appears that compounds with higher solubility in the oil phase than in the aqueous phase are the emulsifying agents that can promote stable water-in-oil emulsions. Crude oils that form very unstable emulsions, e.g. Gullfaks crude oil from the North Sea, require weathering as well as the addition of nickel porphyrins before a stable emulsion will form. The weathering may cause the formation of colloidal asphaltene particles and highly polar compounds that contributes to emulsion stabilization. Essential to the formation of stable water-in-oil emulsions are sufficient amounts of certain polar compounds. If there are insufficient amounts of these compounds, then even the presence of particles and waxes will not lead to the formation of stable emulsions.     

Experimental investigation of wood combustion in a fixed bed with hot air

Waste combustion on a grate with energy recovery is an important pillar of municipal solid waste (MSW) management in the Netherlands. In MSW incinerators fresh waste stacked on a grate enters the combustion chamber, heats up by radiation from the flame above the layer and ignition occurs. Typically, the reaction zone starts at the top of the waste layer and propagates downwards, producing heat for drying and devolatilization of the fresh waste below it until the ignition front reaches the grate. The control of this process is mainly based on empiricism.MSW is a highly inhomogeneous fuel with continuous fluctuating moisture content, heating value and chemical composition. The resulting process fluctuations may cause process control difficulties, fouling and corrosion issues, extra maintenance, and unplanned stops. In the new concept the fuel layer is ignited by means of preheated air (T > 220 °C) from below without any external ignition source. As a result a combustion front will be formed close to the grate and will propagate upwards. That is why this approach is denoted by upward combustion.Experimental research has been carried out in a batch reactor with height of 4.55 m, an inner diameter of 200 mm and a fuel layer height up to 1 m. Due to a high quality two-layer insulation adiabatic conditions can be assumed. The primary air can be preheated up to 350 °C, and the secondary air is distributed via nozzles above the waste layer. During the experiments, temperatures along the height of the reactor, gas composition and total weight decrease are continuously monitored. The influence of the primary air speed, fuel moisture and inert content on the combustion characteristics (ignition rate, combustion rate, ignition front speed and temperature of the reaction zone) is evaluated.The upward combustion concept decouples the drying, devolatilization and burnout phase. In this way the moisture and inert content of the waste have almost no influence on the combustion process. In this paper an experimental comparison between conventional and reversed combustion is presented.     

Modelling piloted ignition of wood and plastics

To gain insight in the startup of an incinerator, this article deals with piloted ignition. A newly developed model is described to predict the piloted ignition times of wood, PMMA and PVC. The model is based on the lower flammability limit and the adiabatic flame temperature at this limit. The incoming radiative heat flux, sample thickness and moisture content are some of the used variables. Not only the ignition time can be calculated with the model, but also the mass flux and surface temperature at ignition. The ignition times for softwoods and PMMA are mainly under-predicted. For hardwoods and PVC the predicted ignition times agree well with experimental results. Due to a significant scatter in the experimental data the mass flux and surface temperature calculated with the model are hard to validate. The model is applied on the startup of a municipal waste incineration plant. For this process a maximum allowable primary air flow is derived. When the primary air flow is above this maximum air flow, no ignition can be obtained.     

In situ burning of emulsions R&D in Norway

SINTEF Applied Chemistry has been working in the field of in situ burning since 1988, beginning with the first open water testing of the 3M fire proof boom which took place on Spitsbergen. In recent years, the focus of SINTEF's research activities in this area has been on the burning of emulsions. An experimental programme was initiated by NOFO in 1990 to study the in situ burning of water-in-oil (w/o) emulsions, as part of a wider NOFO programme ‘Oil spill contingency in Northern and Arctic waters’ (ONA). The research conducted under this programme has addressed many areas of in situ burning including:

• •• study of processes governing burning emulsions
• •• development of ignition techniques for emulsions
• •• effect of environmental conditions on burning
• •• burning crude oil and emulsions in broken ice
• •• uncontained burning of crude oil and emulsions.

     

The weathering properties of four unique crude oils from Australia

This paper reports on the results of weathering studies conducted on four light crude oils from production platforms on the northwest shelf of Australia. The laboratory weathering included both evaporative weathering and emulsification studies. The fresh oils and their topped residues were subjected to a battery of physical and chemical characterization analyses. Detailed analyses were performed for n-alkanes by GC/FID and for mono- and polycyclic aromatic hydrocarbons and phenols by GC/MS. The water-in-oil emulsion formation properties of these oils and their topped residues were investigated at two environmentally significant temperatures (13 and 20°C). The results of the analyses indicate that these oils are very different compositionally and have a wide range of physical and chemical properties. The emulsification properties of these oils and their weathered residues ranged from oils that have very rapid water uptake to oils having no water uptake. Unexpectedly, the very waxy oils had very little water uptake and did not form stable water-in-oil emulsions.     

Heat and chemical treatment of mechanically recovered w/o emulsions

Nearly all crude oils and some heavier refined products form stable water-in-oil (w/o) emulsions when spilled and weathered at sea. Breaking these emulsions and discarding the separated water allow more oil to be recovered and stored by OSRVs (Oil Spill Recovery Vessels) and make the handling of oily waste easier due to viscosity reduction. This study was conducted to determine whether a combination of heat and emulsion breaker is more effective than either technique used alone. The results will be used to prepare guidelines for treatment of w/o emulsions and planning of large-scale tests.A bench-scale laboratory study was carried out using emulsions prepared from different crude oil residues (BCF-17, Alaskan North Slope and Bonny Light) and a Bunker C fuel oil/gas oil blend (IF-80). Tubes containing w/o emulsions, with or without emulsion breaker added, were partially submerged in a water bath at different temperatures to simulate the heating system of the recovered oil tanks onboard the OSRVs. The effectiveness of the emulsion breaking was measured by recording settled water over a 24 h period. The results showed that:

• •• The stability of a w/o emulsion and its response to heat and emulsion breaker is highly dependent on different characteristics of the oil from which it is formed.
• •• Stable w/o emulsions that can be slowly broken by heat alone were, in general, broken much more rapidly if emulsion breaker was added in addition to heat.
• •• The w/o emulsions formed from relatively paraffinic crude oil (e.g. ANS) exhibit faster breaking rates than w/o emulsions formed from crude oils with high asphaltene content, such as BCF-17.
• •• All w/o emulsions formed from the crude oil residues could be broken by the application of moderate amounts of heat. W/o emulsions produced from Bunker C/Diesel oil blend were not broken at all by relatively high heat inputs (up to 100°C) and required both the addition of heat and emulsion breaker to obtain partially breaking.

     

Ignition and burning rates of segregated waste combustion in packed beds

Recent developments in national recycling and re-use programmes for municipal waste have led to segregation of an increasing proportion of waste to enhance material recovery. Several of the segregated streams contain materials that can not viably be re-used or recycled but can be used for energy recovery. In this study, the combustion of cardboard and waste wood was investigated in a small-scale packed bed reactor in order to provide fundamental data for the design/operation of moving bed furnaces. Key parameters of combustion including the ignition and burning rates were evaluated for various air flowrates and compared to the modelling results. Two successive stages of combustion were identified for both samples: the propagation of ignition front into the bed and combustion of the fuel above the ignition front. The burning rate of cardboard reached a peak of about 300 kg/m(2)h at the air flowrate of 936 kg/m(2)h and decreased at higher air flowrates. For waste wood, both the ignition and burning rates increased in the tested range of the air flowrate up to 702 kg/m(2)h, of which the values were very close to those for the cardboard. The model prediction was in good agreement with the test results for waste wood. However, the burning rate for cardboard was under-predicted due to strongly irregular shapes of the fuel.     

Window-of-Opportunity for In Situ Burning

This paper is a summary of the fundamentals that influence the window-of-opportunity for in situ burning of oil at sea. It is a discussion of the variables and factors that influence the capabilities and limitations of in situ burning of oil. This includes the requirements for ignition and sustained burning and the factors that influence the quantity of residue and burn efficiency and the use of emulsion breakers.     

The use of tyre pyrolysis oil in diesel engines

Tests have been carried out to evaluate the performance, emission, and combustion characteristics of a single cylinder direct injection diesel engine fueled with 10%, 30%, and 50% of tyre pyrolysis oil (TPO) blended with diesel fuel (DF). The TPO was derived from waste automobile tyres through vacuum pyrolysis. The combustion parameters such as heat release rate, cylinder peak pressure, and maximum rate of pressure rise also analysed. Results showed that the brake thermal efficiency of the engine fueled with TPO-DF blends increased with an increase in blend concentration and reduction of DF concentration. NO(x), HC, CO, and smoke emissions were found to be higher at higher loads due to the high aromatic content and longer ignition delay. The cylinder peak pressure increased from 71 bars to 74 bars. The ignition delays were longer than with DF. It is concluded that it is possible to use tyre pyrolysis oil in diesel engines as an alternate fuel in the future.     

Norwegian Testing of Emulsion Properties at Sea--The Importance of Oil Type and Release Conditions

This paper is a review of the major findings from laboratory studies and field trials conducted in Norway in recent years on the emulsification of oils spilled at sea. Controlled bench-scale and meso-scale basin experiments using a wide spectrum of oils have revealed that both the physico-chemical properties of the oils and the release conditions are fundamental determinants of the rate of emulsion formation, for the rheological properties of the emulsion formed and for the rate of natural dispersion at sea.During the last decade, several series of full-scale field trials with experimental releases of various crude oils have been undertaken in the North Sea and the Norwegian Sea. These have involved both sea surface releases, underwater pipeline leak simulations (release of oil under low pressure and no gas) and underwater blowout simulations (pressurized oil with gas) from 100 and 850 m depth. The field trials have been performed in co-operation with NOFO (Norwegian Clean Seas Association for Operating Companies), individual oil companies, the Norwegian Pollution Control Authority (SFT) and Minerals Management Services (MMS). SINTEF has been responsible for the scientific design and monitoring during these field experiments. The main objectives of the trials have been to study the behaviour of different crude oils spilled under various conditions and to identify the operational and logistical factors associated with different countermeasure techniques.The paper gives examples of data obtained on the emulsification of spilled oil during these field experiments. The empirical data generated from the experimental field trials have been invaluable for the validation and development of numerical models at SINTEF for predicting the spreading, weathering and behaviour of oil released under various conditions. These models are extensively used in contingency planning and contingency analysis of spill scenarios and as operational tools during spill situations and combat operations.     

Introduction/Overview to In Situ Burning of Oil Spills

In situ burning is an oil spill response technique or tool that involves the controlled ignition and burning of the oil at or near the spill site on the surface of the water or in a marsh (see Lindau et al., this volume). Although controversial, burning has been shown on several recent occasions to be an appropriate oil spill countermeasure. When used early in a spill before the oil weathers and releases its volatile components, burning can remove oil from the waters surface very efficiently and at very high rates. Removal efficiencies for thick slicks can easily exceed 95% (Advanced In Situ Burn Course, Spiltec, Woodinville, WA, 1997). In situ burning offers a logistically simple, rapid, inexpensive and if controlled a relatively safe means for reducing the environmental impacts of an oil spill. Because burning rapidly changes large quantities of oil into its primary combustion products (water and carbon dioxide), the need for collection, storage, transport and disposal of recovered material is greatly reduced. The use of towed fire containment boom to capture, thicken and isolate a portion of a spill, followed by ignition, is far less complex than the operations involved in mechanical recovery, transfer, storage, treatment and disposal (The Science, Technology, and Effects of Controlled Burning of Oil Spills at Sea, Marine Spill Response Corporation, Washington, DC, 1994).However, there is a limited window-of-opportunity (or time period of effectiveness) to conduct successful burn operations. The type of oil spilled, prevailing meteorological and oceanographic (environmental) conditions and the time it takes for the oil to emulsify define the window (see Buist, this volume and Nordvik et al., this volume). Once spilled, oil begins to form a stable emulsion: when the water content exceeds 25% most slicks are unignitable. In situ burning is being viewed with renewed interest as a response tool in high latitude waters where other techniques may not be possible or advisable due to the physical environment (extreme low temperatures, ice-infested waters), or the remoteness of the impacted area. Additionally, the magnitude of the spill may quickly overwhelm the deployed equipment necessitating the consideration of other techniques in the overall response strategy (The Science, Technology, and Effects of Controlled Burning of Oil Spills at Sea, Marine Spill Response Corporation, Washington, DC, 1994; Proceedings of the In Situ Burning of Oil Spills Workshop. NIST. SP934. MMS. 1998, p. 31; Basics of Oil Spill Cleanup, Lewis Publishers, Washington, DC, 2001, p. 233). This paper brings together the current knowledge on in situ burning and is an effort to gain regulatory acceptance for this promising oil spill response tool.     

Water-in-oil emulsion formation: A review of physics and mathematical modelling

A literature review of the physics and modelling of water-in-oil emulsification is presented. The understanding of the physics of emulsion formation is still incomplete, but developing. The formation of emulsions is due to the surfactant-like action of polar compounds (resins) and asphaltenes in oil. These compounds act to maintain small (1–20 μm) droplets of water in oil. Volatile aromatic compounds in crude oils solubilize asphaltenes and resins. Crude oils containing lower quantities of these volatile compounds or BTEX (benzene, toluene, ethylbenzene, xylenes) will form emulsions given sufficient turbulent sea energy. Oils may lose the BTEX component by weathering before being capable of forming stable emulsions. The kinetics and energy of formation of emulsions is not well understood. Emulsions are often reported to form rapidly after the necessary chemical conditions are achieved and where there is significant wave action or other turbulent energy. Oil spill models generally employ a first-order rate law (exponential) to predict emulsion formation.     

The technology windows-of-opportunity for marine oil spill response as related to oil weathering and operations

This paper identifies and estimates time periods as ‘windows-of-opportunity’ where specific response methods, technologies, equipment, or products are more effective in clean-up operations for several oils. These windows have been estimated utilizing oil weathering and technology performance data as tools to optimize effectiveness in marine oil spill response decision-making. The windows will also provide data for action or no-action alternatives. Crude oils and oil products differ greatly in physical and chemical properties, and these properties tend to change significantly during and after a spill with oil aging (weathering). Such properties have a direct bearing on oil recovery operations, influencing the selection of response methods and technologies applicable for clean up, including their effectiveness and capacity, which can influence the time and cost of operations and the effects on natural resources.The changes and variations in physical and chemical properties over time can be modeled using data from weathering studies of specific oils. When combined with performance data for various equipment and materials, tested over a range of weathering stages of oils, windows-of-opportunity can be estimated for spill response decision-making. Under experimental conditions discussed in this paper, windows-of-opportunity have been identified and estimated for four oils (for which data are available) under a given set of representative environmental conditions. These ‘generic’ windows have been delineated for the general categories of spill response namely: (1) dispersants, (2) in situ burning, (3) booms, (4) skimmers, (5) sorbents, and (6) oil-water separators. To estimate windows-of-opportunity for the above technologies (except booms), the IKU Oil Weathering Model was utilized to predict relationships—with 5 m s⁻¹ wind speed and seawater temperatures of 15°C.The window-of-opportunity for the dispersant (Corexit 9527^®) with Alaska North Slope (ANS) oil was estimated from laboratory data to be the first 26 h. A period of ‘reduced’ dispersibility, was estimated to last from 26–120 h. The oil was considered to be no longer dispersible if treated for the first time after 120 h. The most effective time window for dispersing Bonnic Light was 0–2 h, the time period of reduced dispersibility was 2–4 h, and after 4 h the oil was estimated to be no longer dispersible. These windows-of-opportunity are based on the most effective use of a dispersant estimated from laboratory dispersant effectiveness studies using fresh and weathered oils. Laboratory dispersant effectiveness data cannot be directly utilized to predict dispersant performance during spill response, however, laboratory results are of value for estimating viscosity and pour point limitations and for guiding the selection of an appropriate product during contingency planning and response. In addition, the window of opportunity for a dispersant may be lengthened if the dispersant contains an emulsion breaking agent or multiple applications of dispersant are utilized. Therefore, a long-term emulsion breaking effect may increase the effectiveness of a dispersant and lengthen the window-of-opportunity.The window-of-opportunity of in situ burning (based upon time required for an oil to form an emulsion with 50% water content) was estimated to be approximately 0–36 h for ANS oil and 0–1 h for Bonnie Light oil after being spilled. The estimation of windows-of-opportunity for offshore booms is constrained by the fact that many booms available on the market undergo submergence at speeds of less than 2 knots. The data suggest that booms with buoyancy to weight ratios less than 8:1 may submerge at speeds within the envelope in which they could be expected to operate. This submergence is an indication of poor wave conformance, caused by reduction of freeboard and reserve net buoyancy within the range of operation. The windows-of-opportunity for two selected skimming principles (disk and brush), were estimated using modeled oil viscosity data for BCF 17 and BCF 24 in combination with experimental performance data developed as a function of viscosity. These windows were estimated to be within 3–10 h (disk skimmer) and after 10 h (brush skimmer) for BCF 17. Whereas for BCF 24, it is within 2–3 d (disk skimmer) and after 3 d (brush skimmer).For sorbents, an upper viscosity limit for an effective and practical use has in studies been found to be approximately 15,000 cP, which is the viscosity range of some Bunker C oils. Using viscosity data for the relative heavy oils, BCF 17 and BCF 24 (API gravity 17 and 24), the time windows for a sorbent (polyamine flakes) was estimated to be 0–4 and 0–10 d, respectively. With BCF 24, the effectiveness of polyamine flakes, was reduced to 50% after 36 h, although it continued to adsorb for up to 10 d. For BCF 17, the effectiveness of polyamine flakes was reduced to 50% after 12 h, although it continued to adsorb for up to 4 d. The windows-of-opportunity for several centrifuged separators based upon the time period to close the density gap between weathered oils and seawater to less than 0.025 g ml⁻¹ (which is expected to be an end-point for effective use of centrifugal separation technology), were estimated to be 0–18 (ANS) and 0–24 h (Bonnie Light) after the spill. Utilizing the windows-of-opportunity concept, the combined information from a dynamic oil weathering model and a performance technology data base can become a decision-making tool; identifying and defining the windows of effectiveness of different response methods and equipment under given environmental conditions. Specific research and development needs are identified as related to further delineation of windows-of-opportunity.     

CytoSol – Cleaning Oiled Shorelines with a Vegetable Oil Biosolvent

A cleanup process has been developed to aid in the removal of crude or fuel oil from shorelines using CytoSol “biosolvent” formulation based on vegetable oil methyl esters in combination with bioremediation enhancers. The CytoSol biosolvent dissolves and floats the oil, the oil/biosolvent mixture is rinsed off with ambient temperature water for collection as a consolidated layer with skimmers. The collected oil mixture can be recycled as a burner fuel. Nutrient enhancers in the formulation then stimulate the natural biodegradation of the remaining residual hydrocarbons. This new approach minimizes physical and chemical impacts to marine organisms, cleans oiled surfaces effectively, and allows the oiled ecosystem to recover with less mortality than conventional methods involving hot water, detergents or other chemical cleaners. CytoSol is ideally suited for port facilities and waterfronts dealing with occasional small oil spills and has undergone extensive laboratory testing for the US EPA. In 1997, the CytoSol biosolvent was licensed in the state of California as a shoreline cleaner and set up for commercial distribution.CytoSol biosolvent can extract heavy petroleum (crude, fuel oils) off shoreline habitats, mussel-encrusted breakwaters or pilings, and estuary vegetation. The viscosity of the product tends to limit the penetration of the CytoSol/oil mixture into sand and gravel beaches, allowing more of the dissolved oil to be removed from the shoreline by washing. The product has a low specific gravity (0.87), tends to consolidate oil, and is practically immiscible with water, so it facilitates the recovery of spilled oil with conventional skimming and absorbent boom technologies. Since it is non-volatile and non-flammable, there is little danger of explosion or fire when spraying it inside confined spaces.     

Thermal and Flame Retardancy Behavior of Oil Palm Based Epoxy Nanocomposites

The aim of present study was to investigate the thermal properties and flame retardancy behavior of flame retardant (FR) epoxy nanocomposites from chemically treated (bromine water and tin chloride) oil palm empty fruit bunch (OPEFB) nano filler at different filler loading (1, 3, 5%). Thermal properties were evaluated through thermogravimetry analyzer, derivative thermogravimetry and differential scanning calorimetry. FR properties of nanocomposites are evaluated through UL-94 vertical burning test and limiting oxygen index (LOI). The functional group analysis of all composites was made by FTIR spectroscopy. Thermal analysis shows that degradation temperature of epoxy composites shifts from 370 to 410 °C and char yield also increases for 3% loading. Furthermore LOI value of 29% and UL-94 rating of V-0 with no flame dripping and cotton ignition, revealed that 3% oil palm nano filler filled epoxy nanocomposites display satisfactory flame retardancy. The superior flame retardancy of epoxy nanocomposites are attributed to the chemical reactions occurred in the gaseous phases and the profound synergistic flame retardation effect of tin with bromine in the treated nano OPEFB filler. All the epoxy nanocomposites displayed almost similar FTIR spectra with the characteristics metal-halogen bond supporting the synergism. Homogeneous dispersion of 3% oil palm nano filler act as highly effective combustion chain terminating agent compared with 1 and 5% nano OPEFB/epoxy nanocomposites.     

The evaporation of oil spills: Prediction of equations using distillation data

This work follows on extensive empirical studies on the evaporation of oil and petroleum products. A study of the evaporative characteristics of 19 different crude oils and petroleum products was conducted. Best-fit equation parameters were determined for both percentage loss by time and absolute weight loss. All oils except for three (diesel fuel, FCC Heavy Cycle and Bunker C light) were found to fit logarithmic curves. The exceptions noted, fit square root curves with time for periods up to about 5 d. The equation constants were correlated with oil distillation data. The equation constants correlated highly with the percentage distilled at 180°C. Using this correlation, equations were developed by which the oil evaporation can be predicted using the distillation data alone.