Fuel washing

Specific gravity is the weight of the fuel in relation to water. This property is important in the design of centrifugal fuel washing systems. Sulfur content is important in connection with emission concerns and in connection with the alkali metals present in the ash. Sulfur reacting with alkali metals forms compounds that corrode by a process labeled sulfidation. 

An alternate approach to fuel washing is to utilize a vaporized fuel oil system (VFO). This technology was developed as a method for converting natural gas fuel systems to liquid fuel. The process involves mixing steam with the liquid fuel and then vaporizing the mixture. The vaporized mixture exhibits the same combustion properties as natural gas. 

Fuel system fouling is related to the amount of water and sediment in the fuel. A by-product of fuel washing is the desludging of the fuel. Washing rids the fuel of those undesirable constituents that cause clogging, deposition, and corrosion in the fuel system. The last part of treatment is filtration just prior to entering the turbine. Washed fuel should have less than. 025% bottom sediment and water. 

COMBUSTOR OVER-ALL FUEL-AIR RATIO. In general, coke and smoke both increase with increasing fuel-air ratio, although some investigations have shown that smoke can attain a peak point beyond which it decreases. However, the location of this peak value was variable and dependent on other factors. These fuel-air ratio effects can be attributed to more fuel wash on surfaces, richer local fuel-air ratios, and increased thermal cracking of the fuel. Increased burning and erosion might lower coke and smoke formation, however. 

When spillage occurs during fueUng operations, is the spilled fuel washed away completely,... 

This procedure indicates the presence or lack of detergents in the fuel. In fact, when the fuel has additives, a large difference is observed between the weight of deposits before and after washing. 

Hydrogen sulfide concentrates in refinery off gases. Before being used as fuel gas, the gas undergoes an amine (MEA, DEA, etc.) washing step in order to extract the H2S. 

Fuel produced in Tacoma, Wash. Values on ovendry (OD) fuel basis. Ref. 12. 

Condensable hydrocarbons are removed from natural gas by cooling the gas to a low temperature and then by washing it with a cold hydrocarbon hquid to absorb the condensables. The uncondensed gas (mainly methane with a small amount of ethane) is classified as natural gas. The condensable hydrocarbons (ethane and heavier hydrocarbons) are stripped from the solvent and are separated into two streams. The heavier stream, which largely contains propane with some ethane and butane, can be Hquefied and is marketed as Hquefied petroleum gas (LPG) (qv). The heavier fractions, which consist of and heavier hydrocarbons, are added to gasoline to control volatihty (see Gasoline and other motor fuels). 

After epoxidation, propylene oxide, excess propylene, and propane are distilled overhead. Propane is purged from the process propylene is recycled to the epoxidation reactor. The bottoms Hquid is treated with a base, such as sodium hydroxide, to neutralize the acids. Acids in this stream cause dehydration of the 1-phenylethanol to styrene. The styrene readily polymerizes under these conditions (177—179). Neutralization, along with water washing, allows phase separation such that the salts and molybdenum catalyst remain in the aqueous phase (179). Dissolved organics in the aqueous phase ate further recovered by treatment with sulfuric acid and phase separation. The organic phase is then distilled to recover 1-phenylethanol overhead. The heavy bottoms are burned for fuel (180,181). 

Aero-derivative gas turbines eannot operate on heavy fuels, thus if heavy fuels was a eriteria then the frame type turbines would have to be used. With heavy fuels, the power delivered would be redueed after about a weeks of operation by about 10%. On-line turbine wash is reeommended for turbines with high vanadium eontent in their fuel, sinee to counteract vanadium magnesium salts have to be added. These salts cause the vanadium when combusted in the turbine to be turned to ashes. This ash settles on the turbine blades and reduces the cross sectional area, thus reducing the turbine power. 

The centrifugal fuel-cleaning process consists of mixing 5-10% water with the oil plus an emulsion breaker to aid the separation of water and oil. Then a mixer dispenses the wash water into the oil stream to aid the impurities in forming a water solution. The centrifuges then separate this water from the... 

The water washing of the hot seetion of the turbine is required for fuels with high vanadium eontents. The addition of magnesium salts to eneounter the eorrosive aetion of the vanadium ereates ash, whieh deposits on the... 

Effect of Washed Fuel Quality on System Cost... 

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