And pour point

One remaining possibility that is less costly from an energy point of view but needs to be carefully controlled is to incorporate additives called flow improvers. These materials favor the dispersion of the paraffin crystals and in doing so prevent them from forming the large networks which cause the filter plugging. The conventional flow improvers essentially change the CFPP and pour point, but not the cloud point. They are usually copolymers, produced, for example, from ethylene and vinyl acetate monomers ... 

Figure 5.9 shows an example of the efficiency of these products. The reductions of CFPP and pour point can easily attain 6 to 12°C for concentrations between 200 and 600 ppm by weight. The treatment cost is relatively low, on the order of a few hundredths of a Franc per liter of diesel fuel. In practice, a diesel fuel containing a flow improver is recognized by the large difference (more than 10°C) between the cloud point and the CFPP. 

It is mainly in cold behavior that the specifications differ between bome-heating oil and diesel fuel. In winter diesel fuel must have cloud points of -5 to -8°C, CFPPs from -15 to -18°C and pour points from -18 to 21°C according to whether the type of product is conventional or for severe cold. For home-heating oil the specifications are the same for all seasons. The required values are -l-2°C, -4°C and -9°C, which do not present particular problems in refining. 

Performance can be illustrated for example by the time necessary for deaeration or de-emulsification of oils, anti-rust properties, copper strip corrosion test, the flash point in closed or open cup, the cloud and pour points, the foaming characteristics, etc. 

Poly-a-olefins (PAOs) are biodegradable and nontoxic to marine organisms they also meet viscosity and pour point specifications for formulation into oil-based muds [78]. 

The most relevant parameters in pipeline transportation of heavy crude oil are velocity, viscosity, temperature, density, and pour point [691]. Heavy crude... 

Ordinary dicarboxylic acids or dimeric fatty acids are condensed with fatty amines to give emulsion breakers [822,823,1029,1030]. Oxalkylated fatty amines and fatty amine derivatives have properties other than emulsion braking in particular, they can act as corrosion inhibitors and pour-point depressants. 

Petroleum is typically described in terms of its physical properties (such as density and pour point) and chemical composition (such as percent composition of various petroleum hydrocarbons, asphaltenes, and sulfur). Although very complex in makeup, crude can be broken down into four basic classes of petroleum hydrocarbons. Each class is distinguished on the basis of molecular composition. In addition, properties important for characterizing the behavior of petroleum and petroleum products when spilled into waterways or onto land and/or released into the air include flash point, density (read specific gravity and/or API gravity), viscosity, emulsion formation in waterways, and adhesion to soil. 

Generally, the properties of petroleum constituents varying over the boiling range 0 to >565°C (32 to 1050°F). Variations in density also occur over the range 0.6 to 1.3, and pour points can vary from <0 to >100°C. Although these properties may seem to be of lower consequence in the grand scheme of environmental cleanup, they are important insofar as these properties influence (1) the evaporation rate, (2) the abihty of the petroleum constituents or petroleum product to float on water, and (3) the fluidity or mobility of the petroleum or petroleum product at various temperatures. 

The other thermal cracking process is visbreaking. This is a milder thermal process and is mainly used to reduce the viscosities and pour points of vacuum residues to... 

Fuel which does not contain a wax crystal modifier will have temperature differences between the cloud and pour points typically from 15°F to 20°F (8.3°C to 11.1°C). If the difference between the cloud and pour point values is greater than 25°F (13.9°C), it is quite reasonable to believe that the fuel contains a wax crystal modifier. 

For most distillate fuels, cloud point temperatures can range from 50°F to -10°F (10.0°C to -23.3°C) or lower. However, typical cloud point temperatures fall between 6°F and 16°F (-14.4°C and -8.9°C). Distillate blends having a high paraffin content will often have cloud point and pour point values close together, sometimes within 5°F (2.8°C). Highly aromatic blends will usually have cloud and pour point values further apart in temperature. 

Lowering the cloud point and pour point values of a distillate fuel can be accomplished by blending the fuel with a low-wax-content distillate stream such as a kerosene or jet fuel. Also, additives are frequently used in conjunction with kerosene blending or as a substitute for kerosene blending to reduce the pour point of diesel fuel. Additives are not as frequently used to reduce the cloud point of diesel fuel. 

If possible, measure viscosity vs. temperature between cloud and pour points look for a dramatic increase rather than a gradual increase in slope. 

Contrary to what is seen with vegetable oils, biodiesel produced from animal fats has component units that are dominated by saturated alkyl species, and the observed biodiesel properties reflect the presence of these species. The fuel is more stable and degrades less in the presence of air. However, cloud-points and pour-points are higher, meaning that it may show poor performance at cold temperatures. 

Yields and properties for high-severity desulfurization of Kuwait atmospheric tower bottoms are contained in Table XV. Residuum conversion to lighter products is apparent by the higher distillate yields relative to low-severity yields indicated in Table XIV. The LSFO product properties affected to the greatest extent with increasing severity are sulfur, viscosity, and pour point. 

The denormal oils recovered from the experiments were separated from the solvent by batch distillation. Vacuum and nitrogen stripping were applied towards the end, stopping when the oil temperature in the reboiler reached 473 K. Cloud and pour points were determined on the oil products. 

The products obtained were analyzed for composition using high-performance liquid chromatography (HPLC) (LC -10AT Shimadzu, Kyoto, Japan), which consisted of a column (STR ODS-II, 25 cm in length x 4.6 mm in id Shinwa Chemical, Osaka, Japan) operated at 40°C at a flow rate of 1.0 mL/min with methanol as a carrier solvent. The column was packed with silica particles (5-pm particle diameter and 12-nm pore diameter). The cloud and pour points of the obtained biodiesel were then determined by a mini-cloud/pour point tester (Model MPC-102 Tanaka Scientific, Tokyo, Japan) based on ASTM D2500 for cloud point and ASTM D6749 for pour point (14). 

Cloud and Pour Point of Biodiesel Prepared by Supercritical Alcohol Treatment at 350°C and Alkaline-Catalyzed Method... 

Table 2 presents cloud and pour points of biodiesel prepared by our supercritical alcohol method at 350°C. For comparison, the results of the commercial biodiesel fuels are also shown. These results demonstrate that the cloud point of ethyl esters was 3°C lower than that of methyl esters, while that of butyl esters was even lower. The cloud point of methyl ester was similar to that of commercial biodiesel fuels. 

Lubricants are formulated products composed of a base stock, which is either a mineral or synthetic oil, and various specialty additives designed for specific performance needs. Additive levels in lubricants range from 1 to 25% depending on the application. Synthetic base stocks are oligomers of small molecules, synthesized to a defined molecular weight. Important performance indicators include viscosity index which measures the viscosity index behavior over a temperature range, oxidative stability, and pour point. The performance of synthetic and mineral oils (Morse, 1998 Shubkin, 1993) is summarized in Table 2.7. 

Viscosity, volatility and pour point. Poly(a-olefins), diesters and polyol esters usually show improved performance of viscosity, higher viscosity index, significantly lower pour point, and lower volatility (%) loss, compared to petroleum base stock (Table 2.8). 

Table 2.8. Comparison of viscosity, volatility and pour point for synthetic and mineral base stock...

The low viscosity and pour point characteristics of the SRC-II distillates are also attractive in industrial boiler and industrial cogeneration applications substituting for No. 2 fuel oil or natural gas. Demonstration burn programs in industrial boilers are being planned. 

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