US3112789A

US3112789A - Fuel oil and method of operating fuel oil furnaces

Info

Publication number: US3112789A
Application number: US705301A
Authority: US
Inventors: Alian W Percy; William J Zollinger
Original assignee: Pure Oil Co
Current assignee: Pure Oil Co
Priority date: 1957-12-26
Filing date: 1957-12-26
Publication date: 1963-12-03
Anticipated expiration: 1980-12-03

Description

. 3, 1963 A. w. PERCY ETAL FUEL OIL AND METHOD OF OPERATING FUEL OIL FURNACES Filed Dec. 26, 1957 0 =0 20 000 000 -00 000 000 000 000 -00 .00 0 0 W m a. 3; 5 0 000 M 000 W 1 SO G M 0w 6 x, I m 50 u. a 8 2.: a5. 30 3 V .IG- 0 H H V k a w N N wm m m =O 4min N 025: mhmuh ISO: 130m muzmnm ZMxSE.

INVENTORS ALLAN W PERCY BY WILLIAM J ZOLLINGER United States Patent Ofifice 3,1 raise Patented Dec. 3, i003 3,112,789 FUEL GEL AND METHGD F OPERATING FUEL 01L FURNAQES Alian W. Percy and William J. Zoilinger, Crystal Lake,

llL, assignors to The Pure Oil Company, Chicago, EL,

a corporation of Ohio Filed Dec. 26, 1957, Ser. No. 705,301 Claims. (Cl. 158117.5)

This invention relates to new and useful improvements in fuel oils and more particularly to petroleum oils which are used in furnace-oil burners, which oils contain a novel fuel additive for mitigating formation of sooty and carbonaceous deposits in the burner.v

A problem frequently encountered in the use of petroleum burner fuels, e.g., #2 or #3 fuel oils, in furnaces is the accumulation of sooty deposits on boiler walls. A further problem is the accumulation of deposits on the flame rim of rotary oil burners and on the nozzle face of gun-type burners. Petroleum fuel oils also present the problem of excessive tendency to form very dense black smoke unless a substantial excess of combustion air is used.

It is therefore one object of this invention to provide a new and improved fuel oil composition which burns more completely and produces lesser amounts of carbonaceous and sooty deposits.

Another object of this invention is to provide an improved fuel oil having an additive which mitigates formation of sooty and carbonaceous deposits and produces less dense smoke with smaller amounts of combustion air.

A feature of this invention is the provision of an improved fuel oil composition consisting of a burner oil boiling above the gasoline boiling range and containing a small quantity of manganese in the form of an oil-soluble manganese compound of the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof.

Another feature of this invention is the provision of a novel fuel oil composition consisting of a #2 or #3 burner oil containing 0.00125 to 0.005% w. of manganese as an oil-soluble manganese compound of the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof, which producess less dense smoke and less carbonaceous deposits while utilizing smaller amounts of combustion air.

A further feature of this invention is the provision of an improved method of operating an oil burning furnace with dense smoke which comprises burning in the furnace a fuel oil containing an oil-soluble cyclopentadienyl manganese tricarbonyl or derivative thereof.

Other objects and features of this invention will become apparent from time to time throughout the specification and claims as hereinafter related.

In the accompanying drawing there is shown a graph of boiler wall deposits, flame rim deposit-s, and smoke density vs. fuel composition for fuel oils prepared in accordance with this invention.

This invention is based upon our discovery that the addition of very small amounts of oil-soluble manganese compounds of the class consisting of indenyl manganese rioarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof produces a fuel oil which results in greatly decreased carbonaceous deposits in the burner and reduced smoke density. This invention is more particularly concerned withour discovery that a very small but critical proportion of the manganese compound will produce the desired effect. It is only when the additive is used in a manganese concentration of 0.00125 to 0.005% by weight that the advantages of this invention are realized.

In demonstrating this invention a number of tests were made using a #2 furnace oil both with and without additives. The furnace oil used consisted of 65% by volume of fluid-catalytic-cracked light cycle oil, 30% by volume kerosene, and 5% by volume virgin distillate fuel oil. This fuel oil was burned in a Timken wall-flame burner for 4 hours and was found to produce carbonaceous deposits on the boiler wall averaging 0.017" in thickness, and 0.0421 g. of carbonaceous deposits on the flame rim. In burning this oil it was necessary to use 60% excess air over stoichiomctric proportions to obtain an acceptable smoke density of #3 on the Bacharach scale after 123-second sampling period. Under these conditions of operation, the boiler etliciency was 75.2%.

A number of fuel oil compositions were prepared using the #2 furnace oil previously described to which there was added from 0.001 to 0.1% by weight of manganese, as the oil-soluble manganese compound, methyl cyclopentadienyl manganese tricarbonyl. A number of test runs of 4 hours duration each were made in the Timken burner using different fuel oil compositions containing various amounts of the manganese-containing additive. The results of several separate runs using different fuel compositions are set forth in Table I.

TABLE I Boiler Wall Deposits, thickness, inches Flame dc- Concentration,-Wt. percent Mn posits, grams From these and other experiments we have found that fuel oil compositions containing 0.00125 to 0.00 5 by weight of manganese result in reduced deposits in the burner and reduced smoke density. At manganese concentrations of the order of 0.001% and less, and concentrations greater than 0.005%, the manganese additive increases the amount of burner deposits rather than mitigating deposits.

Additional test runs were made in the Tiinken burner using the #2 burner oil with diiferent additive concentrations and with different amounts of combustion air. It

was found that the optimum concentrations of the additive is in the range of about 0.003 to 0.005% by weight of manganese. In that range there is obtained a substantial mitigation of deposits together with a maximum reduction in smoke density. Outside the range of 0.003 to 0.005% of manganese there is some improvement in the amount of deposits, but at the cost of greater smoke density. In the 4-hour Tirnken burner tests, a fuel composition consisting of a #2 burner oil containing methyl cyclopentadienyl manganese tricarbonyl in a concentratio of 0.004% by weight of manganese produced an reduction in lower boiler-wall deposits, a 40% reduction in smoke density and a very slight increase in flame-rim deposits compared to the base fuel oil. In series of test runs using the base fuel oil alone, and the base fuel oil plus methyl cyclopentadienyl manganese tricarbonyl at a concentration of 0.003% by weight of manganese, and using different amounts of combustion air, it was found that the base fuel oil without any additive requires 60% excess air over the stoichiometric amount to obtain an acceptable smoke level of #3 on the Bacharach scale after a 123-second sampling period. Using the same fuel with the manganese additive at a concentration of 0.003% by weight of manganese, it was possible to operate the furnace at an acceptable smoke level of #3 Bachar ach with only 28% excess air. The combination of lower sensibleheat loss at this combustion air setting, reduced burner deposits, and improved combustion efficiency resulted in a boiler efficiency of 79.6% as compared to 75.2% efficicncy for the base fuel oil without any additive. This operation of the furnace with the fuel oil containing 0.003% by Weight of manganese with the lower amount of combustion air results in a saving of about 6% in fuel cost. Our tests indicate that burner fuel oils containing the manganese additive in concentrations of 0.003 to 0.005% by weight of manganese produce smoke having a density less than about #3 on the Bacharach scale (123- second sampling period) when burned with 125 to 140% of the stoichiometric amount of air.

The improved combustion of fuel oils containing these oil-soluble manganese additives is also obtained when these oils are used in gun-type oil burners. This improved combustion, reduction in boiler deposits, and reduction in smoke density is also obtained with other oilsoluble cyclopentadienyl manganese tricarbonyl additives. Other oil-soluble manganese additives which may be used in this invention are indenyl manganese tricarbony, cyclopentadienyl manganese tricarbonyl, and other alkyl-substituted cyclopentadienyl manganese trioarbonyls which may contain any alkyl substituent which does not render the compound insoluble in oil. These additives, when added to a fuel oil at concentrations corresponding to 0.00125 to 0.005% by weight of manganese, result in a fuel oil composition having all of the advantages described above.

While we have fully and completely described our invention with particular emphasis upon several preferred embodiments thereof, we wish it understood that within the scope of the appended claims this invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A fuel oil composition consisting essentially of a furnace grade heating oil containing an amount not substantially less than 0.003% w. and not substantially more than 0.005% W. of manganese as an oil-soluble manganese compound of the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof.

2. A fuel oil composition in accordance with claim 1 in which the manganese compound is indenyl manganese tricarbonyl.

3. A fuel oil composition in accordance with claim 1 in which the manganese compound is cyclopentadienyl manganese tricar-bonyl.

4. A fuel oil composition in accordance with claim 1 in which the manganese compound is methylcyclopentadienyl manganese tricarbonyl.

5. A fuel oil composition in accordance with claim 1 in which the manganese compound is methylcyclopentadienyl manganese tricarbonyl and is present at a manganese concentration of 0.003 to 0.005% by weight.

6. A fuel oil composition in accordance with claim 1 in which the heating oil is a #2 furnace oil.

7. A method of operating an oil burning furnace with reduced amounts of carbonaceous deposits and producing smoke having a density less than about #3 on the Bacharach scale, 123-second sampling period, which cornprises burning a fuel oil as defined in claim 5 with 125 to of the stoichiometric amount of air.

8. A method of operating an oil burning furnace with reduced amounts of carbonaceous deposits and producing smoke of low density which comprises simultaneously metering a furnace grade heating oil and an amount not substantially less than 0.003% W. and not substantially more than 0.005% W. of manganese of a compound of the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof, to said furnace, and burning the oil and manganese compound in said furnace using a small stoichiometric excess of air.

9. A fuel oil composition consisting essentially of liquid hydrocarbon fuel oil suitable for use as a furnace heating oil containing, in an amount sufficient to reduce carbonaceous deposits, an oil-soluble manganese compound selected from the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof.

10. A fuel oil composition consisting essentially of a furnace grade heating oil containing in an amount sufficient to reduce carbonaceous deposits and smoke an oil-soluble manganese compound selected from the group consisting of indenyl manganese tricarbonyl, cyclopentadienyl manganese tricarbonyl, and alkyl derivatives thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,818,416 rown et al. Dec. 31, 1957 2,818,417 Brown et a1. Dec. 31, 1957 2,839,552 Shapiro et al. June 17, 1958 FOREIGN PATENTS 1,140,411 France Mar. 4, 1957 OTHER REFERENCES Chemical and Engineering News, vol. 33, No. 16, Apr. 18, 1955, page 1645.

Claims

8. A METHOD OF OPERATING AN OIL BURNING FURNACE WITH REDUCED AMOUNTS OF CARBONACEOUS DEPOSITS AND PRODUCING SMOKE OF LOW DENSITY WHICH COMPRISES SIMULATANEOUSLY METERING A FURNACE GRADE HEATING OIL AND AN AMOUNT NOT SUBSTANTIALLY LESS THAN 0.003%W. AND NOT SUBSTANTIALLY MORE THAN 0.005%W. OF MANGANESE OF A COMPOUND OF THE GROUP CONSISTING OF INDENYL MANGANESE TRICARBONYL, CYCLOPENTADIENYL MANGANESE TRICARBONYL, AND ALKYL DERIVATIVES THEREOF, TO SAID FURNACE, AND BURNING THE OIL AND MANGANESE COMPOUND IN SAID FURNACE USING A SMALL STOICHIOMETRIC EXCESS OF AIR.