GB2246142A - Hydrocarbon in oil emulsion formation and emissions when burning - Google Patents

Abstract

A hydrocarbon in water emulsion is formed by admixing a mixture of a sulphur containing hydrocarbon in water with an emulsifier wherein said emulsion has a water content of between 5 to 40 volume percent.

Description

A PROCESS FOR CONTROLLING SULFUR OXIDE AND NITROGEN OXIDE FORMATION AND EMISSIONS WHEN BURNING The present invention relates to processes for controlling sulfur oxide and nitrogen oxide emissions when burning. The present invention also relates to bitumen or residual fuel oil hydrocarbon combustible fuels and to hydrocarbon in water emulsions.

The present invention concerns generally a process for the preparation of liquid fuels and the resulting fuel. In particular, this invention concerns a process that allows a high sulfur and nitrogen containing fuel to be converted into energy by combustion with a substantial reduction in sulfur oxide emissions and nitrogen oxide emissions.

Low gravity, viscous hydrocarbons found in Canada, The Soviet Union, United States, China and Venezuela are normally liquid with viscosities arranging from 10,000 to 200,000 CP and API gravities of less than 12. These hydrocarbons are currently produced either by mechanical pumping, steam injection or by mining techniques. Widespread use of these materials as fuels is precluded for a number of reasons which include difficulty in production, transportation and handling of the material and, more importantly, unfavorable combustion characteristics including high sulfur oxide emissions and unburned solids. To date, there are two commercial processes practiced by power plants to reduce sulfur oxide emissions.The first process is furnace limestone injection wherein limestone injected into the furnace reacts with the sulfur oxides to form solid sulfate particles which are removed from the flue gas by conventional particulate control devices. The cost for burning a typical high sulfur fuel by the limestone injection method is between two to three dollars per barrel and the amount of sulfur oxides removed by the method is in the neighbourhood of 50%. A more effective process for removing sulfur oxides from power plants comprises flue gas desulfurization wherein CaO + HzO are mixed with the flue gases from the furnace. In this process 90% of the sulfur oxides are removed; however, the cost for burning a barrel of fuel using the process is between four and five dollars per barrel.Because of the foregoing, the high sulfur content, viscous hydrocarbons have not been successfully used on a commercial basis as fuels due to the high costs associated with their burning.

It is well known in the prior art to form oil in water emulsions for use as a combustible fuel. See for example U.S. Patent Nos. 4,114,015; 4,378,230 and 4,618,348. In addition to the foregoing, the prior art teaches that oil in water emulsions formed from low gravity, viscous hydrocarbons can likewise be successfully combusted as a fuel. See for example British Patent Specification 974,042 and U.S. Patent 4,618,348.

The assignee of the instant application has discovered that sulfur-oxide emissions can be controlled when burning viscous high sulfur containing hydrocarbon in water emulsions by the addition of sulfur capturing additives to the emulsion composition. See U.S.

Application Serial Nos. 875,450 and 014,871.

Naturally, it would be highly desirable to develop a process for the preparation of liquid fuels and a resultant liquid fuel which, upon combustion, has a substantial reduction in sulfur oxide and nitrogen oxide emissions.

It is an object of this invention to provide an improved process for controlling sulfur oxide and nitrogen oxide formation and emissions when burning.

The present invention may provide an additive for addition to a hydrocarbon fuel which, upon combustion of the fuel, acts as a sulfur and nitrogen capturing agent so as to substantially reduce the formation and emission of sulfur and nitrogen oxides.

It is an advantage of the present invention that it provides a process as set forth above which is useful for hydrocarbon in water emulsions to be burned as fuels.

Further objects and advantages of the present invention will appear hereinbelow.

According to one aspect of this invention, there is provided a process for controlling sulfur oxide and nitrogen oxide formation and emissions when burning by forming a combustible fuel prepared from a hydrocarbon containing sulfur and nitrogen comprising: (a) mixing a sulfur and nitrogen containing hydrocarbon with a water soluble additive wherein said water soluble additive consists substantially of a first ingredient, Na+, a second ingredient, Foe++ , and a third ingredient comprising one or more of Mug4+ , Ba++, Ca++, Li*, and Ki wherein Na+ is present in an amount of less than or equal to 40 wt.%, Fe++ is present in an amount of greater than or equal to 0.4 wt.%, and the balance thereof being substantially said third ingredient wherein the ratio of Na+ to Fe++ is between 7.5:1.0 to 100:1.0 and is effective to reduce sulfur oxide and nitrogen oxide formation and emissions to acceptable levels.

According to another aspect of this invention there is provided a bitumen or residual fuel oil hydrocarbon combustible fuel comprising a sulfur and nitrogen containing hydrocarbon and a water soluble sulfur and nitrogen capturing additive wherein said water soluble additive consists substantially of a first ingredient, Na+, a second ingredient Fez+, and a third ingredient comprising one or more of Mg++, Ba++, Ca++, Li+, and K+ wherein Na + is present in an amount of less than or equal to 40 wt.%, Fe++ is present in an amount of greater than or equal to 0.4 wt.% and the balance thereof being substantially said third ingredient wherein the ratio of Na+ to Fe++ is between 7.5:1.0 to 100:1.0 and is effective to reduce sulfur oxide and nitrogen oxide formation and emissions to acceptable levels.

According to another aspect of this invention there is provided a hydrocarbon in water emulsion formed by admixing a mixture of a sulfur containing hydrocarbon in water with an emulsifier wherein said emulsion has a water content of between 5 to 40 volume percent.

The present invention concerns generally a process for the preparation of liquid fuels and the resulting fuel and, more particularly, concerns a process that allows a high sulfur and nitrogen containing fuel to be converted into energy by combustion with a substantial reduction in sulfur oxide emissions and nitrogen oxide emissions.

It is well known in the art to form oil in water emulsions either from naturally occurring bitumens or residual oil in order to facilitate the production and/or transportation of these viscous hydrocarbons. Typical processes are disclosed in U.S. Patent Nos. 3,380,531; 3,467,195; 3,519,006; 3,943,954; 4,099,537; 4,108,193; 4,239,052 and 4,570,656. In addition to the foregoing, the prior art teaches that oil in water emulsions formed from naturally occurring bitumens and/or residual oils can be used as combustible fuels. See for example U.S.

Patent Nos. 4,144,015; 4,378,230 and 4,618,348.

The present invention is drawn to a process for the preparation of a liquid fuel and the resulting fuel which, upon combustion, exhibits a substantial reduction in sulfur oxide emissions and nitrogen oxide emissions.

As noted above, the particular process is useful for fuels in the form of hydrocarbon in water emulsions as disclosed in co-pending Application Serial No. 014,871 and 875,450.

The process of the present invention may comprise admixing a sulfur and nitrogen containing hydrocarbon (either hydrocarbon residual, hydrocarbon in water emulsion, or other suitable hydrocarbon) with a water soluble additive which acts as a capturing agent for sulfur and nitrogen upon combustion of the hydrocarbon as a fuel. in accordance with the present invention, the water soluble additive consists substantially of a first ingredient, Na+, a second ingredient, Fe++ and a third ingredient comprising one or more of Mg++, Boa'', Ca++, Li+, E+ wherein Na+ is present in an amount of less than or equal to 40 wt.% based on the total weight of the water soluble additive, Fe++ is present in an amount of greater than or equal to 0.4 wt.% based on the total weight of the water soluble additive with the balance thereof being substantially said third ingredient. The ratio of Na and Foe++ is about between 7.5 : 1.0 to 100: 1.0.It has been found that the Fe++ addition acts as a nitrogen capturing agent thereby reducing the amount of nitrogen oxide emissions. The Na+ addition acts as a strong sulfur capturing agent for reducing sulfur oxide emissions; however, as the Na+ addition tends to be corrosive to boiler apparatus the amount of Na+ in the additive should be limited. The remaining third ingredient acts as a sulfur capturing agent and is used as a positive addition to complement the amount of Na+ in the additive formulation. The overall additive formulation results in an effective sulfur and nitrogen capturing additive which does not result in serious detrimental corrosion of boiler apparatus.

Reference is now made to the accompanying drawings, in which: Figure 1 is a bar graph showing the effect of additives on the reduction of SO2 emissions; and Figure 2 is a bar graph showing the effect of additives on the reduction of nitrogen oxide emissions.

The process of the present invention is drawn to the preparation and burning of a fuel formed from a naturally occurring bitumen or residual fuel oil product. One of the fuels for which the process is suitable is a bitumen crude oil having a high sulfur content such as those crudes typically found in the Orinoco Belt of Venezuela.

The bitumen or residual oil has the following chemical and physical properties: C wt.% of 78.2 to 85.5, H wt.% of 9.0 to 10.8, 0 wt.% of 0.2 to 1.3, N wt.% of 0.50 to 0.70, S wt.% of 2 to 4.5, Ash wt.% of 0.05 to 0.33, Vanadium, ppm of 50 to 1000, Nickel, ppm of 20 to 500, Iron, ppm of 5 to 60, Sodium, ppm of 30 to 200, Gravity, OKAPI of 1.0 to 12.0 (specific gravity of 1.1 to 1.0), Viscosity (CST), 1220F (67.80C) of 1,000 to 5,100,000 (0.001 to 5.1 m2/s), Viscosity (CST), 2100F (116.70C) of 40 to 16,000 (4 x 10-5 to 0.016 m2/s), IJHV (BTU/lb) of 15,000 to 19,000 (7.2 to 9.1 MJ/Kg), and Asphaltenes wt.% of 9.0 to 15.0.In accordance with one feature of the present invention, a mixture comprising water and an emulsifying additive is mixed with a viscous hydrocarbon or residual fuel oil so as to form an oil in water emulsion. The characteristics of the oil in water emulsion and the formation of same are set forth in the above-referenced co-pending applications which are incorporated herein by reference. In accordance with the present invention, an additive which captures sulfur and nitrogen and prohibits the formation and the emission of sulfur oxides and nitrogen oxides during combustion of the hydrocarbon or hydrocarbon in water emulsion fuel is added to the fuel prior to the combustion of same.The water soluble additive for use in the process of the present invention consists essentially of a first ingredient, Na+ , a second ingredient, Fets and a third ingredient comprising one or more of Mg++, Ba++, Ca++, Li+, K+. In accordance with the particular feature of the present invention the Na+ is present in an amount of less than or equal to 40 wt.% based on the total weight of the water soluble additive.

The Fe++ is present in an amount of greater than or equal to 0.4 wt.% based on the total weight of the water soluble additive. The balance of the water soluble additive is made up by the third ingredient. The ratio of Na to Fe++ in the additive ranges from about between 7.5 1.0 to 100 : 1.0. The preferred formulation for the additive of the present invention used in the process of the present invention consists essentially of Na4 in an amount of between 5 to 40 wt.% based on the total weight of the water soluble additive, Fe4+ in an amount of 0.4 to 2.0 wt.% based on the total weight of the water soluble additive with the balance thereof being substantially said third ingredient.

It has been found that in order to obtain the desired emissions levels with respect to sulfur and nitrogen upon combustion of the fuel produced by the process of the present invention, the additive should preferably be present in a molar ratio of additive to sulfur in the fuel of greater than or equal to 0.500 and more preferably greater than 0.750.

The advantages of the present invention will be clear from consideration of the following example.

EXAMPLE In order to demonstrate the effect of the additive of the present invention on the combustion characteristics of hydrocarbon fuels containing sulfur and nitrogen, ten additive formulations were prepared.

The composition of the additive formulations are set forth hereinbeow in Table I TABLE I Additive Composition (wt.%) No. Mg Na Fe 1 80.5 18.9 0.65 2 62.2 37.3 0.50 3 67.4 32.1 0.40 4 67.4 32.1 0.43 5 79.5 19.2 1.28 6 61.9 37.1 0.99 7 83.0 15.9 1.06 8 67.2 32.0 0.86 9 2.7 97.3 0.00 10 98.8 0.00 1.2 Each of the additives were added to various oil in water emulsions for burning as natural fuels. The fuel characteristics operating conditions and combustion characteristics for the fuels admixed with each additive are set form below in Tables II-XI.

TABLE II ADDITIVE NO. 1 BASELINE EMULSION EMULSION EMULSION EMULSION EMULSION EMULSION #1 #2 #3 #4 #5 FUEL CHARACTERISTICS Additive l/S (Molar Ratio) 0 0.25 0.38 0.50 0.75 0.91 LHV (BTU/lb) 12995 12029 11608 11203 10484 9852 (MJ/Kg) (6.2) (5.8) (5.6) (5.4) (5.0) (4.7) Bitumen, wt.% 74 68.5 66.1 66.1 63.8 59.7 56.1 Water, wt.% 26 31.5 33.9 36.2 40.3 43.9 Sulfur, wt.% 2.8 2.6 2.5 2.4 2.3 2.1 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 59.5 61.7 63.9 68.3 72.7 (Kg/h) (25.0) (27.0) (28.0) (29.0) (31.0) (33.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 149 150 ( C) (82.8) (83.3) (82.8) (83.9) (82.8) (83.3) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 16 10 4 15 11 CO2 (Vol %) 14.3 14.5 14.5 15.0 15.0 14.0 O2 (Vol %) 3.0 3.0 2.9 2.8 2.9 2.9 SO2 (ppm) 2100 1175 1000 700 350 200 SO2 Reduction (%) 0 44.1 52.4 66.7 83.3 90.5 NOx (ppm) 550 435 300 240 140 150 NOx reduction (%) 0 20.9 45.5 56.4 74.6 72.7 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 99.9 99.9 TABLE III ADDITIVE NO. 2 BASELINE EMULSION EMULSION EMULSION EMULSION EMULSION #1 #2 #3 #4 FUEL CHARACTERISTICS Additive 2/S (Molar Ratio) 0 0.33 0.49 0.65 0.70 LHV (BTU/lb) 12995 12029 11608 11203 10484 (MJ/Kg) (6.2) (5.8) (5.6) (5.4) (5.0) Bitumen, wt.% 74 68.5 66.1 63.8 59.7 Water, wt.% 26 31.5 33.9 36.2 40.3 Sulfur, wt.% 2.8 2.6 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 59.5 61.7 63.9 68.3 (KG/h) (25.0) (27.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) (791. 14) Fuel Temperature ( F) 149 150 149 151 149 ( C) (82.8) (83.3) (82.8) (83.9) (82.8) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 5 5 14 7 CO2 (Vol %) 14.3 14.0 14.0 14.0 14.0 O2 (Vol %) 3.0 3.0 2.9 3.0 3.2 SO2 (ppm) 2100 1150 750 380 280 SO2 Reduction (%) 0 45.2 64.3 81.2 86.7 NOx (ppm) 550 260 210 180 120 NOx reduction (%) 0 52.7 62.0 67.3 78.2 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 99.9 (*) Analyzer out of service TABLE IV ADDITIVE NO. 3 BASELINE EMULSION EMULSION EMULSION EMULSION EMULSION #1 #2 #3 #;4 FUEL CHARACTERISTICS Additive 3/S (Molar Ratio) 0 0.30 0.45 0.60 0.90 LHV (BTU/lb) 12995 12029 11608 11203 10484 (MJ/Kg) (6.2) (5.8) (5.6) (5.4) (5.0) Bitumen, wt.% 74 68.5 66.1 63.8 59.7 Water, wt.% 26 31.5 33.9 36.2 40.3 Sulfur, wt.% 2.8 2.6 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 59.5 61.7 63.9 68.3 (Kg/h) (25.0) (27.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 149 ( C) (82.8) (83.3) (82.8) (83.9) (82.8) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 16 26 6 5 CO2 (Vol %) 14.3 14.0 14.5 14.0 14.0 O2 (Vol %) 3.0 3.1 2.7 3.0 2.9 SO2 (ppm) 2100 1250 900 600 250 SO2 Reduction (%) 0 40.5 57.0 71.4 88.1 NOx (ppm) 550 310 210 115 (*) NOx reduction (%) 0 44.0 62.0 79.1 (*) Combustion Efficiency (%) 99.8 99.9 99.9 99.9 99.9 (*) Analyzer out of service.

TABLE V ADDITIVE NO. 4 BASELINE EMULSION EMULSION EMULSION EMULSION #1 #2 #3 FUEL CHARACTERISTICS Additive 4/S (Molar Ratio) 0 0.38 0.56 0.56 LHV (BTU/lb) 12995 12029 11608 11203 (MJ/Kg) (6.2) (5.8) (5.6) (5.4) Bitumen, wt.% 74 68.5 66.1 63.8 Water, wt.% 26 31.5 33.9 36.2 Sulfur, wt.% 2.8 2.6 2.5 2.4 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 59.5 61.7 63.9 (Kg/h) (25.0) (27.0) (28.0) (29.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 ( C) (82.8) (83.3) (82.8) (83.9) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 14 14 13 CO2 (Vol %) 14.3 14.0 14.0 10.0 O2 (Vol %) 3.0 2.9 2.8 3.1 SO2 (ppm) 2100 1100 650 200 SO2 Reduction (%) 0 48.0 69.1 90.5 NOx (ppm) 550 280 240 140 NOx reduction (%) 0 49.0 56.4 74.6 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 (*) Analyzer out of service.

TABLE VI ADDITIVE NO. 5 BASELINE EMULSION EMULSION EMULSION EMULSION EMULSION #1 #2 #3 #4 FUEL CHARACTERISTICS Additive 5/S (Molar Ratio) 0 0.15 0.38 0.50 0.75 LHV (BTU/lb) 12995 12029 11608 11203 10484 (MJ/Kg) (6.2) (5.8) (5.6) (5.4) (5.0) Bitumen, wt.% 74 68.5 66.1 63.8 59.7 Water, wt.% 26 31.5 33.9 36.2 40.3 Sulfur, wt.% 2.8 2.6 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 59.5 61.7 63.9 68.3 (Kg/h) (25.0) (27.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 149 ( C) (82.8) (83.3) (82.8) (83.9) (82.8) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 3 3 4 6 CO2 (Vol %) 14.3 14.0 14.0 14.5 14.5 O2 (Vol %) 3.0 3.0 3.0 3.0 3.0 SO2 (ppm) 2100 1100 725 680 350 SO2 Reduction (%) 0 47.6 65.5 67.6 83.3 NOx (ppm) 550 350 350 200 (*) NOx reduction (%) 0 36.4 36.4 63.6 (*) Combustion Efficiency (%) 99.8 99.9 99.9 99.9 99.9 (*) Analyzer out of service.

TABLE VII ADDITIVE NO. 6 BASELINE EMULSION EMULSION EMULSION EMULSION #1 #2 #3 FUEL CHARACTERISTICS Additive 6/S (Molar Ratio) 0 0.49 0.65 0.70 LHV (BTU/lb) 12995 11608 11203 10484 (MJ/Kg) (6.2) (5.6) (5.4) (5.0) Bitumen, wt.% 74 66.1 63.8 59.7 Water, wt.% 26 33.9 36.2 40.3 Sulfur, wt.% 2.8 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 61.7 63.9 68.3 (Kg/h) (25.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 ( C) (82.8) (83.3) (82.8) (83.9) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 4 10 15 CO2 (Vol %) 14.3 15.0 15.0 15.0 O2 (Vol %) 3.0 2.7 3.0 3.0 SO2 (ppm) 2100 650 350 250 SO2 Reduction (%) 0 69.0 83.3 88.1 NOx (ppm) 550 320 140 140 NOx reduction (%) 0 41.8 74.5 74.5 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 TABLE VIII ADDITIVE NO. 7 BASELINE EMULSION EMULSION EMULSION EMULSION #1 #2 #;3 FUEL CHARACTERISTICS Additive 7/S (Molar Ratio) 0 0.45 0.60 0.90 LHV (BTU/lb) 12995 11608 11203 10484 (MJ/Kg) (6.2) (5.6) (5.4) (5.0) Bitumen, wt.% 74 66.1 63.8 58.7 Water, wt.% 26 33.9 36.2 40.3 Sulfur, wt.% 2.8 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 61.7 63.9 68.3 (Kg/h) (25.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 ( C) (82.8) (83.3) (82.8) (83.9) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 10 6 8 CO2 (Vol %) 14.3 15.0 15.0 14.5 O2 (Vol %) 3.0 3.0 2.9 2.8 SO2 (ppm) 2100 800 550 200 SO2 Reduction (%) 0 61.9 73.8 90.5 NOx (ppm) 550 260 150 62 NOx reduction (%) 0 52.7 72.7 88.7 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 TABLE IX ADDITIVE NO. 8 BASELINE EMULSION EMULSION EMULSION EMULSION #1 #2 #3 FUEL CHARACTERISTICS Additive 8/S (Molar Ratio) 0 0.56 0.75 0.93 LHV (BTU/1b) 12995 11608 1120310484 (MJ/Kg) (6.2) (5.6) (5.4) (5.0) Bitumen , Wt.% 74 66.1 63.8 59.7 Water, Wt.% 26 33.9 36.2 40.3 Sulfur, Wt.% 2.8 2.5 2.4 2.3 OPERATING CONDITIONS Feed Rate (lb/h) 55.1 61.7 63.9 68.3 (Kg/h) (25.0) (25.0) (28.0) (29.0) (31.0) Thermal Input (MMBTU/h) 0.75 0.75 0.75 0.75 (MJ/h) (791.14) (791.14) (791.14) (791.14) Fuel Temperature ( F) 149 150 149 151 ( C) (82.8) (83.3) (82.8) (83.9) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 10 30 7 10 CO2 (Vol %) 14.3 14.0 14.0 14.0 O2 (Vol %) 3.0 3.0 2.9 3.0 SO2 (ppm) 2100 550 180 75 SO2 Reduction (%) 0 73.8 91.4 96.4 NOx (ppm) 550 230 150 100 NOx reduction (%) 0 58.2 67.3 81.8 Combustion Efficiency (%) 99.8 99.9 99.9 99.9 TABLE X ADDITIVE NO. 9 FUEL CHARACTERISTICS BASELINE EMULSION EMULSION EMULSION #1 *2 Additive 9/S (Molar Patio) 0 0.011 0.097 LHV (BTU/lb) 13337 13277 12900 (MJ/Kg) (6.4) (6.4) (6.2) Bitumen, wt.% 78 78 70 Water, wt.% 22 22 30 Sulfur, wt.% 3.0 3.0 2.7 OPERATING CONDITIONS Feed Rate (lb/h) 60.0 60.0 66.7 (Kg/h) (27.2) (27.2) (30.3) Thermal 1 Input (MMBTU/h) 0.82 0.82 0.82 (MJ/h) (864.98) (864.98) (864.98) ( F) 154 154 154 ( C) (85.6) (85.6) (85.6) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 36 27 20 CO2 (Vol %) 13.0 12.9 12.9 02 (Vol %) 3.0 2.9 3.0 SO (ppm) 2347 1775 165 SO2 Reduction (%) 0 24.4 93.1 NOx (ppm) 450 498 434 NOx reduction (%) 0 (9.7) 3.5 Combustion Efficiency (%) 99.8 99.8 99.9 TABLE XI ADDITIVE NO. 10 FUEL CHARACTERISTICS BASELINE EMULSION EMULSION EMULSION #1 #;2 Additive 10/ S (Molar Patio) 0 0.30 0.78 LHV (BTU/1b) 13086 12742 10845 (MJ/Kg) (6.3) (6.1) (5.2) Bitumen, Wt.% 76 74 63 Water, wt.% 24 26 37 Sulfur, wt.% 2.9 2.8 2.4 OPERATING CONDITIONS Feed Pate (lb/h) 55.1 56.2 66.0 (Kg/h) (25.0) (22.1) (29.9) Thermal Input (MMBTU/h) 0.72 0.72 0.72 (MJ/h) (759.50) (759.50) 8759.50) Fuel Temperature ( F) 149 149 149 ( C) (82.8) (82.8) (82.8) Steam/Fuel Ratio (w/w) 0.30 0.30 0.30 Steam Pressure (bar) 2.4 2.4 2.4 COMBUSTION CHARACTERISTICS CO (ppm) 21 30 10 CO2 (Vol %) 13.5 14.0 13.2 02 (Vol %) 3.0 2.9 3-.0 SO2 (ppm) 2357 1250 16.7 SO2 Reduction (%) 0 47.0 92.9 NOx (ppm) 500 430 218 NOx reduction (%) 0 14.0 56.4 Combustion Efficiency (%) 99.8 99.9 99.8 As can be seen from the foregoing tables, Fe++ additions to the additive has a marked effect on reducing nitrogen oxide emissions upon combustion of the fuel'. The comparative effects of Fe++ on nitrogen oxide additions compared to the effect obtained from Na+ and the third ingredient (in this case magnesium) is set forth in Figure 2. Likewise, as can be seen from the foregoing tables II-XI, Na* has a marked effect on reducing sulfur oxide emissions when compared to iron and the third ingredient addition. See Figure 1.

In addition to the foregoing, it is seen from the foregoing combustion data that the molar ratio of additive to sulfur in the hydrocarbon fuel has an effect on the reduction of SOz and nitrogen oxide with reductions of greater than 80% in SO2 being obtained at molar ratios of additive to sulfur of greater than .500 and preferably greater than .750.

In addition to the foregoing, the combustion ash characteristics for Emulsion 5 of Table II and emulsion 2 of Table IX were analysed. The compositions are set forth below in table XII.

TABLE XII ASH CHARACTERISTICS Melting Additive Compound Point ( F) Observations ( C) 3Na2O.V2O5 1562 (868) 2Na2O.V2O5 1184 (658) TABLE X POTENTIALLY Na2O.V2O5 1166 (648) ADDITIVE 9 COROSIVE Na2SO4 1616 (898) Na2O.V2O4.5V2O5 1167 (643) MgSO4 2055 (1142) 3MgO.V2O5 2174 (1208) TABLE II NiSO4 1544 (858) NON-CORROSIVE MgO 2642 (1468) Na2SO4 1616 (898) The ash composition employing additive 9 (a high sodium additive composition) indicates that the ash is potentially corrosive and therefore undesirable.

Accordingly, the ideal additive composition in order to minimize sulfur oxide and nitrogen oxide emissions and reduce the potential for corrosion comprises the first ingredient, Na+ in an amount of about 5 to 40 wt.%, the second ingredient, Fe++ in an amount of between 0.4 to 2.0 wt.% with the balance thereof being substantially said third ingredient.

Claims (2)

1. A hydrocarbon in water emulsion formed by admixing a mixture of a sulfur containing hydrocarbon in water with an emulsifier wherein said emusion has a water content of between 5 to 40 volume percent.

2. A hydrocarbon in water emulsion substantially as herein described in any example.