There are several methods that can be used to estimate liquid density of pure or mixture compound [39]. The temperature range of this correlation extends from a reduced temperature of 0. Table 4. In this study, reference data are these obtained experimentally at K from this study. According to this method, the density of vegetable oils can be estimated by the Equation 7 below:.
Group functional and there parameters A i , B i and C i can be seen in this literature [39]. No temperature limitations are specified for this method except for the fact that the temperature must be less than the critical. This method is limited to temperatures less than 0. For thermal conductivity estimation of rapeseed and jatropha oils respectively, two methods based on group contribution method proposed by Sastri, and Sato-Riedel [39] were selected.
The upper temperature limit for Sato-Riedel method is the critical point and thermal conductivity will not be calculated at temperatures above this. Two methods were selected to estimate the heat capacity at constant pressure. The most accurate method was chose by comparing the values of the estimated properties with experimental values of this study. Zong et al. The heat capacity C p l can be estimated by Equation 17 according to this approach.
The detail of Zong et al. Ceriani et al. The equation used is given by Equation The detail of Ceriani et al. For all the physical properties, the Average Relative Deviation ARD which formula given by Equation 19 is used to evaluate the accuracy of the different studied methods and for the validation of the estimated values. Table 5 shows the results of critical properties and normal boiling point predicted by the MG method for rapeseed and Jatropha oils.
To test the reliability of MG method, the estimated values of this study have been compared with literature data. However, there are literature data for only canola oil which is another variety of rapeseed oil and then is used for comparison. Table 5. Rapeseed and Jatropha oil estimated critical properties and normal boiling point by MG method. As shown in Table 5 , the relative deviation between literature data and estimated values for rapeseed and jatropha oils are low for T B , T C and V C confirming the reliability of MG method.
Large deviations were only observed for critical pressure in both cases. Poling et al. This could therefore explain the high ARD for vegetable oils, since they are formed of triglycerides which are large molecules. The experimental data of this work for physical properties of rapeseed and Jatropha oils, for the temperature range to K, using the different methods and devices above mentioned are given in Table 6. Figure 1 and Figure 2 show curves evolution of experimental density, heat capacity, thermal conductivity and dynamic viscosity.
Figures indicate that all physical properties of the two oils above mentioned decrease as the temperature increases except the heat capacity which increases along with temperature. For the viscosity, the effect of temperature is related to the decrease of intermolecular forces, making easier the flow and therefore the reduction of viscosity [46].
Table 6. Experimental values for secondary physical properties of rapeseed and jatropha oils obtained in this work. Figure 1. Experimental density and dynamic viscosity curves evolution of rapeseed and Jatropha versus temperature. Figure 2. Experimental thermal conductivity and heat capacity curves evolution of rapeseed and Jatropha versus temperature.
As the mass of the fluid remains identical, this expansion causes a decrease in the density. However, the specific heat of the two oils increases along with increasing temperature.
This trend confirms the experimental results obtained by Morad et al. They also found that this increase in heat capacity with temperature is related to the mobility of the molecules depending on the temperature.
Figure 3 and Figure 4 show respectively the estimated and experimental density values for rapeseed and Jatropha oils as a function of temperature. In both cases, the estimated and experimental data show the same trend with temperature: density decreases when temperature increases. In particular when temperature increases the Gunn Yamada density curve gets closer to the experimental one while the Ihmels et al.
In addition, low deviations between experimental values and predicted one were found with the two methods as shown in Table 7 showing the goodness. Figure 3. Experimental and estimated density of rapeseed oil.
Figure 4. Experimental and estimated density of jatropha oil. Table 7. ARD values for the different methods used. However, in view of the purpose of this work, Gunn Yamada correlative method is recommended for extrapolation of density at high temperatures typically observed during the injection phase in diesel engine.
Ihmels et al. Two estimation methods have been discussed. In Figure 5 and Figure 6 , calculated dynamic viscosities are compared with experimental values for rapeseed and jatropha oils. For temperatures lower than K, large errors result, as illustrated on both figures for the two methods. Because generally for a temperature range from the freezing point to the normal boiling temperature, when the natural logarithm of dynamic viscosity is assume to be a linear reciprocal absolute temperature, good approximation is found.
Therefore, for low temperatures, deviations can be observed. In the literature [39] there are generally distinct methods of correlations or viscosities at low temperatures and for high temperature. However, the problem lies in the impossibility of combining the two estimated viscosities. Figure 5. Experimental and estimated dynamic viscosity of rapeseed oil. Figure 6. Experimental and estimated dynamic viscosity of jatropha oil.
Table 8 shows the reproducibility error of the device for measuring the thermal conductivity of vegetable oils. The measuring device was found to lead to a reproducibility error of about 1. Two estimation methods have been discussed: Sastri and Riedel methods [39]. In Figure 7 and Figure 8 , calculated thermal conductivity is compared with experimental values for rapeseed and jatropha oils.
As expected, in both figures, the results show that the thermal conductivity decreases when the temperature increases.
However, the difference between the thermal conductivity obtained by the two estimative methods is very large. Table 8. Reproducibility errors for measuring the thermal conductivity of vegetable oils.
Figure 7. Experimental and estimated thermal conductivity of rapeseed oil. Figure 8. Experimental and estimated thermal conductivity of jatropha oil. Sastri method. Riedel method overestimates the rapeseed and jatropha oils thermal conductivity. Then, Sastri method gives good agreement between predicted thermal conductivity and experimental thermal conductivity data in the studied temperature range.
The higher agreement of Sastri method with experimental values is probably due to the fact that this correlative method involves the contribution of functional groups as well as correction factors, whereas the Riedel method involves only a reference value and a reduced temperature. The materials that were evaluated were five common structural steels carbon steel, 2.
The composition of these steels is shown in Table 5. As can be seen in the table, the chromium concentration is variable among the steel grades. Table 5. The test samples included unstressed sheet coupons and U-bend stressed specimens, as shown in Figure The thickness, width, and length of the sheet bar coupons measured 1.
The U-bend specimens were 1. The exposure chambers were equipped with a condenser in the vapor region to collect and return volatile organic components to the liquid phase. Argon was used as the cover gas.
One set of specimens was immersed in the liquid phase of the test fuels, while a second set was placed in the vapor phase that existed above the surface level of test fuels.
The corrosion results for the five steel materials are shown in Tables 6 and 7 for the specimens that were immersed in the test fuel liquid and vapor spaces, respectively. The corrosion rate of the carbon steel, 2. The highest corrosion rates occurred for the carbon steel and the 2. For these two steel types, moderate corrosion between 0. Onboard HFO fueling systems are primarily composed of carbon steels and stainless steels.
These results show that tanks and piping composed of carbon steel, 2. Table 6. Table 7. In contrast, the carbon steel specimens exposed to neat bio-oil showed much higher corrosion for the liquid versus the vapor phase exposures.
The most likely reason for the increased corrosivity in the vapor phase is due to the higher vapor pressures of the acid and water components of the bio-oil.
The higher volatility of the acetic acid and water means that the vapor region will have higher levels of these corrosive species relative to the liquid fuel blend. Therefore, the corrosion rate is higher in the liquid phase.
In this study, a high-viscosity, low-sulfur heavy fuel oil was successfully blended with highly acidic bio-oil derived via fast pyrolysis of pine feedstock. The ASTM D spot test results showed blend uniformity between the two fuel types and that asphaltene precipitation was not promoted by the added bio-oil. This feature further confirms bio-oil compatibility with HFO.
Perhaps, more importantly, significant energy and cost savings can be realized by reducing the level of heating needed to reduce the viscosity of HFO with the addition of bio-oil. An aging study showed that the blend viscosities were unaffected by continuous operation at extended periods. This finding along with the other stability tests shows that the polymerization of bio-oil was inhibited by the HFO. The measured lubricity values of bio-oil were lower than for HFO and showed a linear relationship with the blend level.
The heating value, or energy content, of the blends also showed a linear behavior with bio-oil content. These linear relationships with bio-oil content further infer uniformity of the fuel blends. The combustion quality was successfully assessed for HFO-containing low blend levels. Corrosion tests conducted on selected structural alloys showed that unacceptable corrosion may occur for carbon steel, 2. The corrosion rates for L and L steels with the neat bio-oil were negligible.
Author Information. Michael D. Beth L. Brian C. James R. The authors declare no competing financial interest. Heavy Fuel Oils , Report No. Product Dossier No. Brussels , Google Scholar There is no corresponding record for this reference. Notes on Heavy Fuel Oil. Houston, TX ; Marine Fuel Facts Impact of maltene and asphaltene fraction on mechanical behavior and microstructure of bitumen. Materials and Structures , 49 , — , DOI: Hofko, B.
As a widely accepted concept, bitumen consists of four fractions that can be distinguished by their polarity. Highly polar asphaltene micelles are dispersed in a viscous phase of sats. Different concns. In an interdisciplinary study the impact of the maltene phase and asphaltenes on the linear viscoelastic behavior and the microstructure of bitumen were analyzed by creep recovery testing in a DSR and by at.
Therefore, bitumen was sepd. It was found that the artificially produced, pptd. Asphaltenes play an important role in the typical viscoelastic behavior of bitumen being mainly responsible for stiffness and elasticity.
Also, their concn. Asphaltene Stability in Crude Oils. Society of Petroleum Engineers , Proceedings of the World Engineers Elsevier Ltd. A review, with 71 refs. Fast pyrolysis of biomass is one of the most promising technologies for converting biomass to liq.
The pyrolysis liqs. However, bio-oils are totally different from petroleum fuels. Therefore, the successful utilization of bio-oils in terms of liq. This review concs. Energy Fuels , 24 , — , DOI: American Chemical Society.
Bio-oil is a renewable energy source that is produced from the pyrolysis of lignocellulosic biomass. The pyrolysis oils are emulsion-like fluids, contg. A series of rheol. In general, the viscosity of the oils was independent of the shear rate i. However, some of the hardwood samples shear thin at lower temps.
Oscillatory frequency sweeps were also performed. All of the oil samples were found to be viscous liqs. A strong dependence of viscosity upon the temp. Water content and acidity were also measured and compared to viscosity. The water content was found to have a stronger effect on viscosity than acidity.
Generally, the oils that had higher water contents had lower viscosities. Viscosity does not correlate with the acid no. While the acid no.
The microstructure of the oils was investigated using optical microscopy and small-angle neutron scattering. Optical microscopy did not show discrete boundaries between the aq. The neutron-scattering profiles showed that a fractal structure is present in two of the three oils studied.
Energy Fuels , 18 , — , DOI: A review. Fast pyrolysis of biomass is one of the most recent renewable energy processes to have been introduced. It offers the advantages of a liq. Bio-oil is a renewable liq. Fast pyrolysis has now achieved a com. Bio-oils have been successfully tested in engines, turbines, and boilers, and have been upgraded to high-quality hydrocarbon fuels, although at a presently unacceptable energetic and financial cost. The paper critically reviews scientific and tech. Biomass and Bioenergy , 70 , — , DOI: Connatser, Raynella M.
Integrating biofuels with conventional petroleum products requires improvements in processing to increase blendability with existing fuels. This work demonstrates anal. To protect infrastructure from damage and reduce the cost assocd. Established techniques form an ample basis for bio-liqs. However, early in the upgrading process, the unique phys.
In this work, the water soly. TAN , to include aq. The results of corrosion product evaluations using several different sources of real bio-oil are discussed in the context of the unique AMTAN and CE anal. Klinger, Jordan; Carpenter, Daniel L. Here, the authors report on the effects of loblolly pine residue variability on material throughput, pilot plant uptime, operator intervention, product yield, and product quality for grinding, fast pyrolysis, and hydrotreating operations.
Grinder overloads in the size redn. During fast pyrolysis operations, downtime was caused by bridging in the feed and char removal systems and plugging in the condensation system. Cohesion of feedstock and char leading to system plugging was less frequent for higher ash feedstocks, and differences in condenser plugging behavior between high and low ash feedstocks were obsd.
The catalyst stability of the bio-oil stabilization step was strongly dependent on the S content in the bio-oil, which was higher for the high-ash residue oils. Lower moisture content in the starting biomass was consistent with lower S content in bio-oil. Yields and properties of hydrotreated fuel products showed minimal deference among the bio-oils. This work explores reliability issues surrounding conversion of loblolly pine resources to renewable fuels with respect to feedstock quality.
SAE Int. Fuels Lubr. SAE International. This study summarizes the peer-reviewed literature regarding the use of raw pyrolysis liqs. PLs created from woody biomass as fuels for compression-ignition CI engines. First, a brief overview is presented of fast pyrolysis and the potential advantages of PLs as fuels for CI engines. Second, a discussion of the general compn. Next, a synopsis is given of the peer-reviewed literature describing exptl. This literature conclusively indicates that raw PLs and PL blends cannot be used as "drop-in replacements" for diesel fuel in CI engines, which is reflected in part by none of the cited studies reporting successful operation on PL fuels for more than twelve consecutive hours.
Based on the reported failure modes, some recommendations are offered for improving performance, reliability, and safety when fueling CI engines with PLs. It appears that PL-derived fuels are most likely to find sustainable CI-engine applications only after a cost-effective pre-use processing strategy is identified to address significant issues regarding fuel instability, materials incompatibilities e.
Energy Fuels , 14 , — , DOI: To investigate their ignition delay and combustion behavior, expts. It was found that while the indicated thermal efficiency of both pyrolysis oils equaled that of the diesel fuel, they exhibited excessive ignition delays and required a moderate degree of combustion air preheating to ignite reliably.
Despite the longer ignition delays assocd. Using a three parameter fit for vaporization, ignition, and combustion rate, the model showed that the longer ignition delays of the bio-oils result from slow chem. The model also showed that the heat release profiles of the bio-oils are consistent with slow combustion chem.
As a result, whereas diesel combustion is predominantly mixing limited, pyrolysis oil combustion is predominantly limited by chem. Energy , , DOI: An investigation was performed to det. The ignition temp. These larger droplets may not vaporize and ignite , or they may take longer to do so because they spray angle becomes narrower and moves further away from the ignition spark. The most common symptoms are:. A noisy flame that pulsates and becomes unstable.
This can lead to appliance soot-up. Another matter to consider is the maximum input rating of an appliance. Some appliances are designed to operate near maximum capacity. This may lead to excessive heat upon the burner, or a smoky combustion process. If the problem is cold oil, see if the above-ground tank can be moved inside or buried below the ground frost line and the supply lines insulated.
Also, a one-pipe system is preferred over a two-pipe set-up where a choice is possible. The two-pipe system will circulate the rated capacity of the fuel unit gear-set, which could be 22 GPH. The one-pipe set-up draws ONLY the firing rate of the nozzle. This allows the oil to warm to the surrounding ambient temperature as it is drawn toward the nozzle.
Some servicemen say heat tape gets good results. But, make sure you have the approval of your local building and electrical codes. This produces droplets of oil which are easier to vaporize and ignite.
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