Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L10/00—Use of additives to fuels or fires for particular purposes
  • C10L10/02—Use of additives to fuels or fires for particular purposes for reducing smoke development
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/12—Inorganic compounds
  • C10L1/1233—Inorganic compounds oxygen containing compounds, e.g. oxides, hydroxides, acids and salts thereof
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
  • C10L1/326—Coal-water suspensions
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
  • C10L1/328—Oil emulsions containing water or any other hydrophilic phase
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/14—Organic compounds
  • C10L1/18—Organic compounds containing oxygen
  • C10L1/188—Carboxylic acids; metal salts thereof
  • C10L1/1881—Carboxylic acids; metal salts thereof carboxylic group attached to an aliphatic carbon atom

Definitions

• This invention relates to methods for burning high sulfur (S) content combustible compositions, wherein low, environmentally-acceptable, oxidized sulfur compound (SOX) emissions are realized. More particularly, this invention relates to the mixing of high sulfur content compounds with admixtures of soluble and insoluble sulfur sorbents. Use of such admixtures, it has been found, results in a far greater reduction on SOX emissions, than would be expected from the activity of each sorbent used alone, while exhibiting no deleterious effects on the combustion efficiency.
• S sulfur
• SOX oxidized sulfur compound
• Viscous hydrocarbons present in natural deposits have been generally classified as viscous crude oils, bitumen or tar and have been variously called heavy crudes, native bitumen, natural bitumen, oil sands, tar sands, bituminous sands or deposits and natural asphalts, all of which materials are chemically gradational and nearly indistinguishable without standardized analyses.
• hydrocarbon substrates may be linear, branched, cyclic or aromatic.
• the microbes In order to rapidly assimilate such water- insoluble substrates, the microbes require a large contact area between themselves and the oil. This is achieved by emulsifying the oil in the surrounding aqueous medium. Hydrocarbon degrading microbes frequently synthesize and excrete surface active agents which promote such emulsification.
• Torulopsis gropengiesseri was found to produce a sophorose lipid, while rhamnolipids are reported by K. Hisatsuka et al. [Agric. Biol. Chem., 3_5, 686 (1971)] to have been produced by Pseudomonas aeruginosa strain S7B1 and by S. Itoh et al. [Agric. Biol. Chem., 3___ * 2233 (1971)] to have been produced by another P ⁇ aeruginosa strain, KY4025. The growth of Corynebacterium hydrocarboclastus on kerosene was reported by J.E. Zajic and his associates [Dev. Ind.
• Acinetobacter calcoaceticus ATCC 31012 (previously designated Acinetobacter sp. ATCC 31012 and also called RAG-1) produces interfacially active extracellular protein-associated lipopolysaccharide biopolymers called emulsans. These biopolymers are produced and build up as a capsule or outer layer around the bacterial cell during growth and are eventually released or sloughed off into the medium, from which they can be harvested as extracellular products.
• Acinetobacter calcoaceticus ATCC 31012 produces a-emulsans when grown on ethanol or fatty acid salts [U.S. Patents Nos.
• the -emulsans and 3-emulsans can be derivatized to an O-deacylated form called psi-emulsans [U.S. Patent No. 4,380,504].
• the ⁇ -emulsans, ⁇ -emulsans and psi- emulsans can be deproteinized to yield apo- ⁇ -emulsans, apo- 0-emulsans and apo-psi-emulsans, respectively [U.S. Patents Nos. 4,311,830; 4,311,829 and 4,311,831, respectively].
• Ornithine-Lipids Pseudomonas Thiobacillus, Agrobacterium, Gluconobacter
• Penicilliu Aspergillus, Acinetobacter, Micrococcus, Candida
• a class of pollutants that has, recently, become a major concern is that of gaseous sulfur compounds such as H_S, COS, SO_, SO_ and the like. When released into the atmosphere, these compounds, it has been postulated, can react with atmospheric moisture and oxygen to form sulfuric acid, which results in "acid rain", severely corrosive precipitation that is detrimental to plant and animal life. For this reason, particularly stringent restrictions have been placed upon the amount of gaseous sulfur compounds, notably the oxidized forms of sulfur produced during sulfur burning, SOX, which can be released into the atmosphere during combustion of fuels. Such restrictions have made it nearly impossible to utilize high sulfur content fuels in standard applications.
• An alternative approach involves the removal of the sulfur from the fuel prior to the combustion. This may be accomplished by extracting the sulfur components into solvents having a stronger affinity for the sulfur compounds than the fuel. Such solvents are, however, expensive and often will extract significant amounts of combustible fuel components along with the sulfur. For these reasons, this method has proven to be impractical.
• H-S hydrogen sulfide
• the fuel is mixed with sulfur sorbents which act to remove the sulfur and the oxidized sulfur compounds during the combustion process.
• sulfur sorbents which act to remove the sulfur and the oxidized sulfur compounds during the combustion process.
• a particular advantage of this approach is that solid compounds can be utilized as sorbents. Such compounds will remain in the solid phase during combustion, thus facilitating the ultimate collection of the sulfur-sulfur sorbent conjugates. Also, because the reaction occurs in the combustion zone, the temperatures are quite high rendering the sorbent species quite reactive; thus, the kinetics of the absorption are directed in favor of the SOX binding.
• a major drawback of this method is the lack of adequate sulfur sorbents, thus making efficient sulfur removal difficult. For example, Cottell (U.S.
• Patent 3,941,552 found in experiments using coal/water c slurries that when lime (CaO) is present in a 50% excess of the stoichiometric requirement (to achieve 100% S removal) , a 50% reduction in SOX levels is observed; this increases to 80% when twice the stoichiometric requirement of lime is used.
• Dooher et al. conducted burn experiments on water-in-oil 0 emulsions of high sulfur oil utilizing soda ash (Na-CO_) as a sorbent and claimed to have found somewhat better results (50% of the stoichiometric requirement of Na_CO achieved a 45% SO- removal) .
• Na-CO_ soda ash
• the use of high concentrations of sodium salts is 5 undesirable due to the well-known side effect of fouling, which necessitates frequent cleaning of the boiler.
• This invention provides a method for decreasing SOX emissions during combustion of high sulfur content hydrocarbons and coals by adding to such materials an admixture of insoluble and soluble sulfur sorbents prior to the burning. It has been found that, remarkably, this admixture of sulfur sorbents provides a higher degree of SOX emission reduction than would be predicted on the basis of the reduction efficiency of each sorbent individually, i.e., the admixture components exhibit a catalytic effect on the SOX removal efficiency of each other. By use of these sorbents, the SOX emissions during combustion of high sulfur content hydrocarbons (including coals) can be brought within environmentally acceptable levels, making such materials commercially useful.
• This invention also provides methods for reducing the SOX emissions during the combustion of viscous, high sulfur content hydrocarbons by forming preatomized fuels (hydrocarbon-in-water emulsions) and adding the insoluble/soluble sorbent admixture to the preatomized fuels.
• preatomized fuels hydrocarbon-in-water emulsions
• insoluble/soluble sorbent admixture achieves a remarkable reduction in SOX emissions when the preatomized fuel is burned. Similar reductions can be seen using coal/water slurries treated with the sorbents as fuels.
• This invention also provides fuel compositions comprised of sulfur-containing combustible compounds, including preatomized fuels and coal slurries, and admixtures of soluble/insoluble sulfur sorbents, which c exhibit reduced SOX emissions when burned.
• hydrocarbosol is defined as any bioemulsifier-stabilized hydrocarbon-in-water emulsion 0 wherein the individual hydrocarbon droplets are essentially surrounded or covered by water-soluble bioemulsifier molecules predominantly residing at the hydrocarbon/water interface, which bioemulsifier molecules form an effective barrier against droplet coalescence and hence promote the 5 maintenance of discrete hydrocarbon droplets suspended or dispersed in the continuous, low-viscosity aqueous phase.
• water-soluble is defined to include water-dispersible substances.
• viscous hydrocarbon is defined as any naturally occurring crude oil or any residual oil remaining after refining operations which is generally characterized by a viscosity of about 10 2-106 centipoise or greater and 5 otherwise generally, but not necessarily, characterized by an
• viscous hydrocarbon also encompasses the following nomenclature: 0 vacuum residuals, vis-breaker residuals, catalytic-cracker residuals, catalytic hydrogenated residuals, coker residuals,
• pre-atomized fuel is defined as any hydrocarbosol and any viscous hydrocarbon-in-water emulsion formed by methods described herein for use as a combustible fuel.
• bioemulsifier is defined as any biologically derived substance which, by virtue of any combination of characteristics including, but not limited to, high molecular weight, polymeric nature, highly specific three-dimensional structure, hydrophobic and hydrophilic moieties and sparing solubility in hydrocarbons, binds tightly to the hydrocarbon/water interface and essentially covers the surface of individual hydrocarbon droplets in hydrocarbon-in-water emulsions, effectively maintaining discrete droplets and preventing coalescence, and thereby imparting substantial stability to hydrocarbon-in-water emulsions.
• An example of a bioemulsifier is ⁇ -emulsan.
• biosurfactant is defined as any biologically derived substance which reduces the interfacial tension between water and a hydrocarbon and, as a result, reduces the energy requirement (mixing energy) for creation of additional interfacial area.
• An example of a biosurfactant is a glycolipid.
• surfactant package is defined as any composition useful for forming hydrocarbon-in-water emulsions of viscous hydrocarbons generally characterized by a paraffin content of about 50% by weight or less and an aromatic content of about 15% by weight or greater with viscosities of about 100 centipoise or greater at 150°F, which composition may comprise a chemical surfactant or a combination of chemical co-surfactants or a combination of co-surfactant(s) and biosurfactant(s) or a combination of chemical surfactant(s) and bioemulsifier(s) or a combination of chemical surfactant(s) , biosurfactant(s) and bioemulsifier(s) , and which may also include chemical emulsion stabilizers, and which may be in aqueous form.
• emulsans which reflects the polysaccharide structure of these compounds and the exceptional bioemulsifier activity of these materials, generically identifies those capsular/extracellular microbial protein-associated lipoheteropolysaccharides produced by Acinetobacter calcoaceticus ATCC 31012 and its derivatives or mutants, which may be subdivided into the ⁇ -emulsans and the ⁇ -emulsans.
• the name “apoemulsan” generically identifies those deproteinized lipopolysaccharides obtained from the emulsans.
• ⁇ -emulsans defines those extracellular microbial protein-associated lipopolysaccharides produced by Acinetobacter calcoaceticus ATCC 31012 and its derivatives or mutants in which the lipopolysaccharide components (i.e., without the associated protein) are completely N-acylated and partially O-acylated heteropolysaccharides made up of major amounts of D-galactosamine and an aminouronic acid, the lipopolysaccharide components containing at least 5 percent by weight of fatty acid esters in which (1) the fatty acids contain from about 10 to about 18 carbon atoms; and (2) about 50 percent by weight or more of such fatty acids are composed of 2-hydroxydodecanoic acid and 3-hydroxydodecanoic acid. It follows, therefore, that the deproteinized ⁇ -emulsan are called "apo- ⁇ -emulsans.”
• -emulsans defines those extracellular microbial protein-associated lipopolysaccharides produced by Acinetobacter calcoaceticus ATCC 31012 and its mutants in which the lipopolysaccharide components (i.e., without the associated protein) are completely N-acylated and partially O-acylated heteropolysaccharides made up of major amounts of D-galactosamine and an a inouronic acid, the lipopolysaccharide components containing less than 5 percent by weight of fatty acid esters in which (1) the fatty acids contain from about 10 to about 18 carbon atoms; and (2) less than 50 percent by weight of such fatty acids are composed of 2-hydroxydodecanoic acid.
• the deproteinized ⁇ -emulsans are called "apo- ⁇ -emulsans.”
• psi-emulsans defines the O-deacylated extracellular protein-associated microbial polysaccharides obtained from the emulsans, the protein-free components of such psi-emulsans being completely N-acylated heteropolysaccharides made up of major amounts of D- galactosamine and an aminouronic acid and containing from 0 to 1 percent of fatty acid esters in which, when present, the fatty acids contain from about 10 to about 18 carbon atoms. These protein-free components are called "apo-psi-emulsans," regardless of how they are prepared.
• polyanionic heteropolysaccharide biopolymers defines those biopolymers in which (a) substantially all of the sugar moieties are N-acylated aminosugars, a portion of which is N-acylated-D-galactosamine and another portion of which is N-acylated aminouronic acid, a part of the N-acyl groups of such heteropolysacchardide being N-3-hydroxydodecanoyl groups; and (b) at least 0.2 micromoles per milligram of such heteropolysaccharide consist of fatty acid esters in which (1) the fatty acids contain about 10 to about 18 carbon atoms and (2) about 50 percent by weight or higher of such fatty acids are composed of 2- hydroxydodecanoic acid and 3-hydroxydodecanoic acid.
• SOX defines all oxidized sulfur compounds produced during sulfur combustion without reference to the degree of oxidation.
• hydrocarbon is defined as any naturally occurring petroleum crude oil, residue, or distillate, including coals.
• sulfur containing combustible compound refers to all combustible compounds which contain measurable quantities of sulfur compounds and which, when burned, produce measurable amounts of SOX.
• high sulfur content includes all compounds which, when burned, have a SOX emission level which exceeds the standard set by the local regulatory authority.
• slurry includes all dispersoids wherein a ground or pulverized solid phase is dispersed in a continuous liquid phase.
• FIG. 1 is a graphical representation of the Removal Efficiency as a function of % excess oxygen with the addition of 1% and 2% CaCO. as a S sorbent, at 30 and 50% furnace loads.
• FIG. 2 is a graphical representation of the Removal Efficiency as a function of the % excess oxygen for three CaC0 3 /Na-CO_ S sorbent systems at 30 and 50% furnace loads.
• FIG. 3 is a graphical representation of the Removal Efficiency as a CaCO_/10% calcium acetate sorbent system at a 30 and 50% furnace load.
• the surfactant packages suitable for forming preatomized fuels can be formulated with a wide variety of chemical and microbial surface active agents and are preferably formulated with water-soluble surface active agents to provide for the formation of oil-in-water, as opposed to water-in-oil, emulsions.
• the surfactant packages can be formulated with numerous chemical surfactants, used alone or in conjunction with chemical co-surfactants of the same type (e.g., a combination of water-soluble nonionic surfactants) or of different types (e.g., a combination of water-soluble nonionic, anionic, cationic and/or amphoteric surfactants) , and can be further formulated in combination with (a) a water-soluble biosurfactant or combination of biosurfactants as co-surfactant(s) and/or (b) a water-soluble bioemulsifier or combination of bioemulsifiers as emulsion stabilizer(s) .
• chemical emulsion stabilizers may also be used in place of bioemulsifiers.
• surfactant packages comprising only microbial surface active agents, i.e., combinations of biosurfactants and bioemulsifiers.
• the surfactant packages vary with the type of viscous oil to be emulsified.
• the following general compositions are offered by way of illustration.
• surfactant packages can be formulated to comprise at least one chemical surfactant and at least one bioemulsifier. They can also be formulated to comprise at least one water-soluble nonionic surfactant, at least one water-soluble anionic surfactant, and at least one bioemulsifier.
• surfactant packages can be formulated to comprise at least one water-soluble non-ionic surfactant or at least one anionic surfactant or combinations of non-ionic surfactants c and anionic surfactants and which can further comprise biosurfactants and/or bioemulsifiers.
• Carboxylic Acid Esters 5 Carboxylic Amides, Ethoxylated Amines, polyoxyalkylated Polyalkylene Oxide Block Copolymers Poly(oxyethylene-co-oxypropylene) Block Copolymers Reverse Block Copolymers 0 Polyalkylene Oxide Copolymers
• the preferred water-soluble nonionic chemical surfactants are ethoxylated alkyl phenols and ethoxylated alcohols.
• the preferred water-soluble nonionic surfactants are, again, ethoxylated alkyl phenols and also polyoxyalkylated amines.
• the ethoxylated alkyl phenols are of the general formula:
• R represents an alkyl group containing from about 8 to about 12 carbon atoms (i.e., about C to about C -)
• x represents the number of alkyl groups and is either 1 or 2
• n represents the number of ethoxy groups (moles ethylene oxide) which can range from about 1 to about 100.
• preferred ethoxylated alkyl phenols are those having R groups of 8 or 9 carbon atoms and having from about 7 to about 100 ethoxy groups.
• An example of a particularly preferred ethoxylated alkyl phenol is monononylphenol with about 40 ethoxy groups.
• the ethoxylated alcohols are of the general formula:
• R represents an aliphatic group (linear or branched) containing from about 6 to about 18 carbon atoms and wherein n represents the number of ethoxy groups which can range from about 2 to about 100.
• ethoxylated alcohols include ethoxylated trimethylnonanols with about 3 to about 9 ethoxy groups and ethoxylated secondary alcohols having R groups of about 11 to about 15 carbon atoms with about 3 to about 30 ethoxy groups, but preferably greater than about 7 ethoxy groups.
• the polyoxyalkylated amines are of the general formula:
• R xV CH 2>2 wherein R represents an oxyalkyl group containing either 2 or 3 carbon atoms. These R groups can range in number from about 4 to about 500, and that number is represented by x.
• the number of amine groups is represented by y and the alkyl group is preferably ethyl (C_H.) .
• Preferred polyoxyalkylated amines are those having R groups of 2 or 3 carbon atoms and having from about 50 to about 450 oxyalkyl groups.
• An example of a particularly preferred polyoxyalkylated amine is a polyoxyalkylated diamine with about 50 ethoxy groups and about 60 propoxy groups.
• Alkylbenzenesulfonates polymerized Alkylarylsulfonates, short chain
• the preferred water-soluble anionic chemical surfactants are sulfonated or sulfated forms of nonionic surfactants.
• ethoxylated alcohol sulfates are preferred.
• sulfonated or sulfated ethoxylated alkylphenols and ethoxylated alcohol sulfates are preferred.
• alkylaryl sulfonates are also preferred anionic chemical surfactants.
• the ethoxylated and sulfated alcohols are of the general formula: R(OC 2 H 4 ) n OS0 3 M
• R represents an aliphatic group containing from about 6 to about 16 carbon atoms, preferably from about 12 to about 14, n represents the number of ethoxy groups which can range from about 1 to about 4, preferably from about 2 to about 3, and M includes, but is not limited to, ammonium (NH4) , sodium (Na) , potassium (K) , calcium (Ca) or triethanolamine, preferably ammonium.
• NH4 ammonium
• Na sodium
• K potassium
• Ca calcium
• triethanolamine preferably ammonium
• an example of a particularly preferred nonethoxylated alcohol sulfate is the sodium salt of a sulfated lauryl alcohol.
• the sulfated ethoxylated alkylphenols are of the general formula:
• R represents an aliphatic group containing at least about 8 or 9 carbon atoms
• n represents the number of ethoxy groups which can range from about 1 to about 100, preferably from about 4 to about 9 and M includes, but is not limited
• e preferably ammonium.
• An example of a particularly preferred sulfated ethoxylated alkylphenol is the ammonium salt of a sulfated nonylphenol ethoxylate containing, but not limited to, about 4 ethoxy groups.
• alkylaryl sulfonates are of the general formula:
• Ar is an aromatic group which is benzyl, naphthyl, phenyl, tolyl, xylyl or ethylphenyl
• R is a linear or branched chain alkyl group containing from about 2 to about 16 carbon atoms
• n is 1 or 2
• m is 1 or greater
• x is at least about 1
• M includes, but is not limited to, ammonium, sodium, potassium, calcium or triethanolamine.
• alkylaryl sulfonate is a modified amine dodecylbenzene sulfonate.
• an example of a particularly preferred alkylaryl sulfonate is the sodium salt of polymerized alkylnaphthalene sulfonate.
• the preferred water-soluble microbial surface active agents for use in the surfactant packages are any microbial or other biologically-derived substances which function as bioemulsifiers, i.e., substances which, by virtue of such characteristics as large molecular weight, polymeric nature, highly specific three-dimensional structure, hydrophobic and hydrophilic nature, and sparing solubility in oil, effectively cover the oil/water interface maintaining discrete, individual oil droplets in oil-in-water emulsions thereby substantially stabilizing emulsions from coalescence.
• bioemulsifiers are heteropolysaccharide biopolymers produced by bacteria of the genus Acinetobacter and the genus Arthrobacter, and in particular, those produced by strains of Acinetobacter calcoaceticus.
• Such Acinetobacter heteropolysaccharide biopolymers include, but are not limited to, polyanionic heteropolysaccharide biopolymers, ⁇ -emulsans, ⁇ -emulsans, psi-emulsans, apo- ⁇ - emulsans, apo- ⁇ -emulsans and apo-psi-emulsans produced by Acinetobacter calcoaceticus ATCC 31012 (deposited at the American Type Culture Collection in Rockville, MD) defined in Section 4 and described in U.S. Patents Nos.
• Acinetobacter calcoaceticus materials that can be used are the products of strains NS-1 (NRRL B-15847) , NS-4 (NRRL B-15848), NS-5 (NRRL B-15849) , NS-6 (NRRL B-15860) and NS-7 (NRRL B-15850) .
• the foregoing "NS" strains have been deposited at the Northern Regional Research Center in Peoria, IL and have been assigned the foregoing NRRL accession numbers.
• Acinetobacter calcoaceticus The "NS" strains of Acinetobacter calcoaceticus are described by Sar and Rosenberg, Current Microbiol. 9_(6):309- 314 (1983) , hereby incorporated by reference.
• Other Acinetobacter heteropolysaccharide biopolymers are those produced by Acinetobacter calcoaceticus BD4 [Taylor and Juni, J. Bacteriol. 81: 688-693 (1961) , hereby incorporated by reference] .
• Particularly preferred Acinetobacter heteropolysaccharide biopolymers are the ⁇ -emulsans, the production of which is further described in U.S. Patents Nos. 4,230,801 and 4,234,689 (hereby incorporated by reference).
• the ⁇ -emulsans are characterized by a Specific Emulsification Activity of about 200 units per milligram or higher, where one unit per milligram of Specific Emulsification Activity is defined as that amount of emulsifying activity per milligram of bioemulsifier which yields 100 Klett absorption units using a standard hydrocarbon mixture consisting of 0.1 ml of 1:1 (v/v) hexadecane/2-methylnaphthalene and 7.5 ml of Tris- Magnesium buffer.
• Acinetobacter bioemulsifiers can be used in the surfactant packages in a variety of forms including, but not limited to, post-fermentation whole broth cell-free (Millipore-filtered, e.g.) or partially cell-free supernatants of post-fermentation culture broth; the cells themselves; protease-treated, liquid or dried materials; and protease-treated, ultrafiltered, liquid or dried materials.
• the surfactant packages may als be formulated with water-soluble cationic chemical surfactants, including, but not limited to, oxygen-free amines, oxygen-containing amines, amide-linked amines and quaternary ammonium salts.
• Use of cationic chemical surfactants in conjunction with microbial surface active agents would require that the charge characteristic of the biological compounds be considered. For example, cationic chemical surfactants would probably best be used in conjunction with neutral microbial surface active agents and would probably best not be used in conjunction with the preferred polyanionic heteropolysaccharide bioemulsifiers.
• Lipopeptides Bacillus subtilis Bacillus mesentericus Candida petrophilum Streptomyces canus Corynebacterium lepus Nocardia asteroides Mycobactrium paratuberculosis Mycobacterium fortuitum
• Ornithine lipids Pseudomonas rubescens Thiobacillus thioxidans Agrobacterium tumefaciens Gluconobacter cerinus
• ATCC 31012 Pseudomonas fluorescens Yersinia pseudotuberculosis Yersinia pestis S. calcoaceticus Other Surface Active Agents unknown or poorly Pseudomonas spp. characterized Pseudomonas aeruginosa Pseudomonas oleororans Pseudomonas putida Pseudomonas desmolyticam Pseudomonas methanica Corynebacterium spp. Corynebacterium sp.
• ATCC 21910 Achromobacter agile Achromobacter tropunctatum Actinomyces o1igocarbophilus Aureobasidium pullulans Arthrobacter sp. ATCC 21908 Micrococcus spp. Micrococcus sp. ATCC 21909 Micrococcus cerificans ATCC
• Surfactant packages can be formulated from nonioni chemical surfactants or combinations of nonionic and anionic chemical surfactants without bioemulsifiers but preferably, for emulsion stabilization, with bioemulsifiers in the rang of about 1% to about 50% by weight. Surfactant packages comprising bioemulsifiers in the range of about 10% to about 20% by weight and particularly around 15% by weight are preferred.
• Surfactant package compositions can be used to emulsify or emulsify and substantially stabilize numerous viscous hydrocarbons in oil-in-water emulsions which may be directly burned. Viscous hydrocarbons encompass naturally- occuring viscous crude oils (also called heavy crude oils) a well as residual bottom-of-the-barrel products from refineries, such as vacuum resid, other residual fuel oils and asphalt. [See Section 4, Nomenclature, supra.] While low gravity does not necessarily coincide with high density, these characteristics are generally correlated in viscous hydrocarbons.
• Low API gravity generally at or below about 20°API. This is the most frequently used criterion, both because it is easily measured and because 20°API crude roughly corresponds to the lower limit recoverable with conventional production techniques.
• lighter crudes may also be emulsified and/or stabilized with surfactant packages, and such emulsion formation, to yield preatomized fuels, often aids in the handling and combustion of these materials. Since lighter crudes can also contain measurable quantities of sulfur, the use of formation of preatomized fuels from these lighter oils may be useful for the purposes of this invention.
• viscous hydrocarbons which can be emulsified with the surfactant packages and which are most useful to emulsify for transportation and/or burning purposes can be generally defined as having a paraffin content of about 50% by weight or less and an aromatic content of about 15% by weight or greater with viscosities of about 100 centipoise or greater at 150°F.
• the viscous residuals generally are characterized by a paraffin content in the range from about 4% to about 40% by weight, an aromatic content in the range from about 15% to about 70% by weight and an asphaltene content from about 5% to about 80% by weight.
• the types of crude oils that can be successfully emulsified and stabilized with surfactant packages include Boscan (Venezuela) crude, an east Texas crude, Jibaro and Bartra (Peru) crudes, El Jobo (Venezuela) crude, and a Kansas crude.
• the specific viscous residuals that can be successfully emulsified and stabilized with surfactant packages include California vacuum resid, Oklahoma vacuum resid, German visbreaker resid, Texas visbreaker resid, catalytic hydrogenated resid, ROSE bottoms, cutback tar, pyrolysis pitch, and propane deasphalted tar.
• Number 6 oils sometimes referred to as "Bunker C” oils, are high-viscosity oils used mostly in commercial and industrial heating. Their utilization normally requires preheating in the storage tank to permit pumping, and additional preheating at the burner to permit atomizing. The extra equipment and maintenance required to handle Number 6 fuels in nonemulsified form usually precludes its use in small installations.
• the ASTM standard specifications for Number 6 fuel oils are summarized in Table VI ["Standard Specification for Fuel Oils," ASTM Designation D396-80, in: 1981 Book of ASTM Standards, Part 23].
• Viscosity values in parentheses are for information only and not necessarily limiting.
• the surfactant packages of Section 6.1 can be used to form oil-in-water emulsions containing as much as about 90% by volume of the hydrocarbons described in Section 6.2.
• the aqueous phase into which the hydrocarbon is emulsified can be deionized water, water from a municipal source, or any 5 water, even water with relatively large amounts of dissolved solids such as connate waters or brines, normally located in proximity to oil production, transportation or utilization sites.
• the aqueous phase can also be an alcohol/water mixture such as methanol/water, ethanol/water or other lower alkanol/water mixtures, and may further contain additives such as anti-corrosion agents, anti-pollution agents or combustion improvers.
• Oil-in-water emulsions preferably contain oil/water ratios of about 50/50 to about 80/20, and more preferably from about 60/40 to about 75/25.
• the surfactant packages of Section 6.1 can be used in proportions of surfactant package:hydrocarbon from about 1:100 to about 1:2,000 by weight. The proportion used can depend on the type of hydrocarbon to be emulsified and/or the purpose for emulsifying it.
• Oil-in-water emulsion formation can be brought about by any number of suitable procedures.
• the aqueous phase containing an effective amount of surfactant package can be contacted with the hydrocarbon phase by metered injection just prior to a suitable mixing device.
• Metering is preferably maintained such that the desired hydrocarbon/water ratio remains relatively constant.
• Mixing devices such as pump assemblies or in-line static mixers can be used to provide sufficient agitation to cause emulsification.
• Some low gravity residual hydrocarbons are extremely viscous and require very high temperatures to make them fluid enough to handle. Such hydrocarbons can be characterized by a viscosity greater than about 1000 cp at 212°F. Maintaining such high temperatures is not economically feasible for the long term storage and transportation of these hydrocarbons. Also, it is not economically feasible to blend these viscous hydrocarbons with much lighter oils (cutter stock) due to either the quantity of lighter oil required to achieve a viscosity which can be handled or the unfavorable characteristics of the viscous hydrocarbon which do not allow for homogeneous blending of lighter oils.
• a novel approach to handling extremely viscous hydrocarbons is the stable dispersion of such viscous hydrocarbons into water to form pre-atomized fuels.
• Pre ⁇ atomized fuel formation is achieved by heating the viscous hydrocarbon to a high temperature in order to make it fluid.
• the hot hydrocarbon phase is brought in contact with the aqueous phase containing appropriate surfactants and/or stabilizers as described in Section 6.1.
• a key to achieving successful pre-atomized fuel formation is the maintenance of pressure throughout the entire process such that the aqueous phase is not allowed to vaporize.
• the aqueous phase By maintaining the appropriate pressure, i.e., the pressure required to prevent the water in the aqueous phase from boiling, the aqueous phase remains in a liquid state, thus allowing the stable dispersion of the hydrocarbon phase into a continuous water phase.
• the resulting hot pre-atomized fuel may be rapidly cooled using an appropriate heat exchange device so that the outlet temperature of the pre-atomized fuel is below the vaporization temperature of the aqueous phase at ambient pressure.
• the pressure may be reduced and the mixture cooled by flashing a portion of the water contained in the pre-atomized fuel.
• phase consist of a low API gravity hydrocarbon bottom phase, a water/surfactant middle phase, and a high API gravity hydrocarbon upper phase.
• separation may be due to the slow cooling of the pre-atomized fuel which allows sufficient time for the occurrence of complex interactions that may be attributed to both "sticky state" and Ostwald ripening phenomena.
• the tendency toward separation can be decreased by the use of an appropriate heat exchange device or method to rapidly quench the freshly formed pre-atomized fuel to a temperature at least about 100°F below the softening point of the hydrocarbon.
• a stable pre-atomized fuel is achieved that does not separate with time. It is further theorized that the rapid cooling of the hot pre-atomized fuel does not allow sufficient time for the complex interactions stated above to occur.
• An economical way to increase the btu content of a liquid fuel is achieved by incorporating a high softening point hydrocarbonaceous material (such as coal, coke, ROSE residual, etc.) into a lower softening point fuel. This is usually accomplished by grinding a high softening point hydrocarbon to form very small particles (usually approximately 100 ⁇ ixx in size) and then, dispersing the solid particles in the liquid fuel. The dispersion of a solid in a liquid, however, usually results in the production of a fuel with unfavorable characteristics such as increased viscosity.
• a high softening point hydrocarbonaceous material such as coal, coke, ROSE residual, etc.
• a novel method of economically utilizing a high softening point hydrocarbonaceous material is achieved by incorporating it into a pre-atomized fuel. This is accomplished by first grinding a material of high softening point to form very small particles (generally less than about 30 ⁇ m) and then forming a slurry by dispersing the particles in a continuous aqueous phase containing a pre-atomized fuel-compatible surfactant package.
• the slurry of dispersed particles is mixed at an appropriate ratio with a pre-atomized fuel formulated from a hydrocarbon other than that used to form the slurry.
• a pre-atomized fuel formulated from a hydrocarbon other than that used to form the slurry.
• the mixing of a slurry with a pre-atomized fuel results in a liquid fuel which has a viscosity lower than either the slurry or the pre-atomized fuel prior to mixing.
• the reasons for the reduced viscosity observed in a slurry/pre-atomized fuel mixture are not fully known; however, without wishing to be bound or restricted by any particular theory, applicants believe that the reduction of particle-to-particle interaction is a contributing factor.
• hydrocarbon droplets of hydrocarbon-in-water emulsions generally rise to the surface and "float" on the aqueous phase in a process known as creaming, provided the density of the hydrocarbon phase is less than that of the aqueous phase and the droplets in the dispersed phase are too big to be stabilized by Brownian motion. If the "cream” remains undisturbed for a given period of time, the droplets coalesce, giving rise to two separate phases.
• the emulsans, particularly ⁇ -emulsan are extremely effective in retarding coalescence and the emulsan-stabilized droplets in the "cream" are easily redispersible in the aqueous phase.
• emulsion stability The principal factors controlling emulsion stability are electrostatic (charge) effects and steric effects.
• electrostatic (charge) effects and steric effects The properties of emulsans lend themselves to optimal exploitation of these mechanisms. Their large molecular weight and highly specific three-dimensional structure result in an efficient coverage of the hydrocarbon/water interface. This effectively prevents oil-to-oil contact when collisions occur between adjacent droplets.
• the polyanionic nature of emulsans causes the surfaces of emulsion droplets to be negatively charged which creates repulsive forces and significantly decreases the collision frequency between hydrocarbon droplets.
• hydrocarbons may be too viscous for conventional processing or have characteristics (i.e., low gravity; excessive paraffinic, aromatic, and/or asphaltic contents; etc.) which make them unfavorable to incorporate into stable pre-atomized fuels.
• One method to reduce viscosity for processing or alleviate unfavorable characteristics is blending the unfavorable hydrocarbon with one which is favorable resulting in a hydrocarbon having characteristics suitable for pre-atomized fuel formation. In this way an otherwise unusable hydrocarbon can be "adjusted" to a usable form.
• Combustible compounds which have high S content include, but are not limited to, coals, especially the softer or bituminous coals, and the heavier petroleum fractions such as heavy crude oils, asphalts, resids, bottoms, and tars (see sec. 6.2 supra.) .
• Such compounds cannot be commercially used as fuels without reducing the SOX emissions.
• a wide array of inorganic and organic salts can be used as sulfur sorbents which result in SOX reduction in combustion gases (often, the SOX can be reduced to acceptable levels as defined by local regulatory standards thereby making the fuels "clean burning") .
• Such compounds react with the oxidized sulfur at some time during the combustion process to form the corresponding sulfates and sulfites.
• a particular advantage of reacting during the combustion process is that, at the high temperatures realized within and in the vicinity of flame, the sorbents become highly reactive species and the kinetics of the reaction strongly favor the binding of the SOX.
• a major factor in determining the sorbent efficiency is the actual physical particle size, as only exposed surfaces will be reactive. As the particle size decreases, the surface area per unit mass of sorbent increases, causing the efficiency to increase. It is, therefore, desirable to achieve as small a particle size as practical.
• Sorbents can be conveniently divided into two classes based on their water solubility: soluble sulfur sorbents and insoluble sulfur sorbents.
• the insoluble sulfur sorbents are generally the less expensive of the two, but their efficiency is usually not as great.
• the insoluble sorbents are generally found in abundance naturally and include the alkaline earth metal carbonates such as calcium carbonate (CaCO , limestone) and magnesium carbonate (MgCO ) . Minerals containing high quantities of these compounds such as dolomite (a mixture of CaCO- and 3
• MgCO_ are also useful as sorbents.
• a primary criterion for the selection of an insoluble sorbent is that it be relatively inexpensive, since its efficiency will be low.
• the soluble sorbents are generally more expensive. Included in this category are calcium, sodium, and magnesium salts of formate, acetate, propionate and higher organic radicals. Another soluble sorbent, sodium carbonate (soda ash, Na-CO-) is much less expensive than any of the organic salts, but this compound suffers from the drawback of causing boiler fouling, greatly limiting its utility in commercial applications.
• the soluble sorbents are generally much more efficient in reducing SOX emissions than the insoluble sorbents, particularly in fuels where water forms a significant component of the mixture, such as in coal/ water slurries or preatomized fuels (where water is the continuous phase) .
• Admixtures of soluble and insoluble sorbents can be utilized to achieve highly efficient SOX reduction during combustion of high sulfur content fuels including preatomized fuels and coal/water slurries. These admixtures, it has been discovered, exhibit a remarkable reduction in SOX levels; in fact, the SOX reduction efficiency of the admixture exceeds the combined efficiency of each component separately. Apparently each component exerts a catalytic effect on the SOX absorbing ability of the other.
• the quantity of soluble sorbents required to achieve this effect is quite small, depending on the particular sorbents used.
• a concentration of soluble sorbent ranging from 0.5-20% (by weight) and, preferably, from 1-10% in the admixture will produce a reduction in SOX levels sufficient to meet the local environmental standards. Since the admixture greatly increases the SOX reduction efficiency as compared with either sorbent alone, the concentration of the admixture in the fuel can also be kept low, generally 0.5-25% (by weight). Thus, the amount of sorbent admixture used is quite low for the SOX reduction observed.
• an admixture of 90% CaCO- and 10% CaAc (calcium acetate) was found to exhibit a removal efficiency (a measurement of the theoretical SOX reducing capacity to the actual SOX reduction observed) of 31-44% for a sulfur-containing resid. Even when this amount is corrected for the presence of CaAc by assuming the CaAc reacted with sulfur with 100% efficiency, (a very conservative estimate since, alone, it exhibits a removal efficiency of 50%) , the removal efficiency is still 26-40%, as compared with 9-19% observed with an equivalent amount of calcium carbonate as the only sorbent and making the comparison under similar operating conditions. Thus, the SOX reducing capacity is greatly enhanced by forming the admixture.
• the sorbent admixture can b added to coal, either in a water slurry or solid form, resulting in reduced SOX emissions. Since, as stated supra, large amount of coal reserves have high sulfur content, the invention permits the coal to be burned in an-environmentall acceptable manner.
• the ⁇ -emulsans produced by Acinetobacter calcoaceticus ATCC 31012 during fermentation on ethanol are known bioemulsifiers as described in U.S. Patent No. 4,395,354, incorporated by reference supra.
• the ⁇ -emulsans used in the experiments described infra were technical grade materials (unless otherwise indicated) which were prepared in either of two ways. Both methods of preparation involved enzyme treatment and drying but differed in the order in which these steps were performed.
• centrifuged (approximately 90% cell-free) fermentation broth containing ⁇ -emulsans resulting from a fermentation of Acinetobacter calcoaceticus ATCC 31012 in ethanol medium was drum-dried and the resulting material was treated in the following manner prior to use.
• a 10% by weight suspension of the material, so-called technical grade ⁇ -emulsan was prepared in deionized water and heated to 50°-60°C while continuously stirring.
• the pH of the suspension was adjusted to pH 8.5 by adding 50% by weight sodium hydroxide (diluted, if necessary).
• Protease enzyme (NOVO Industries, 1.5M Alcalase) was added at a level of 1 part protease:500 parts solid ⁇ - emulsan.
• the mixture was allowed to remain at 50 ⁇ -60 ⁇ C while being stirred for about three hours. Reactions were run to completion as judged by the absence of visible precipitable emulsan following centrifugation of the reaction mixture. After completion of the enzyme treatment, the reaction mixtures were raised to approximately 70°C to denature the protease and stop its activity. The solutions were cooled to room temperature and Cosan PMA-30 (Cosan Corporation) , a preservative, was added at a level of 1 part Cosan:500 parts ⁇ -emulsan solution.
• Cosan PMA-30 Cosan Corporation
• enzyme treatment of the ⁇ - emulsan was performed prior to drum drying according to the folowing protocol. Fermentation broth containing ⁇ -emulsan resulting from a fermentation of Acinetobacter calcoaceticus ATCC 31012 in ethanol medium was centrifuged to remove approximately 90% of the bacterial cells.
• protease enzyme (as previously described) was added in a ratio of 1 gram protease:500 units per milligram of Specific Emulsification Activity (where one unit per milligram of Specific Emulsification Activity is defined as that amount of emulsifying activity per milligram of bioemulsifier which yields 100 Klett absorption units using a standard hydrocarbon mixture consisting of 0.1 ml of 1:1 (v/v) hexadecane/2-methylnaphthalene and 7.5 ml of Tris- Magnesium buffer) .
• the protease reaction was run to completion as described supra.
• Fermentations of Acinetobacter calcoaceticus ATCC 31012 were run on ethanol as described in U.S. Patent No. 4,395,354. The following fractions of the resulting broth were used to formulate surfactant packages: whole broth, supernatants, cells, enzyme-treated whole broth, enzyme- treated supernatants, enzyme-treated cells (where the enzyme treatment was as described for the second method in Section 7.1.1. supra) , homogenized cells, boiled cells, and so-called "Millipore emulsan.” Millipore emulsan is prepared by Millipore filtering whole broth to remove cells, followed by enzyme treatment (described supra) and ultrafiltration. The foregoing preparations were used in liquid or wet form. The Millipore emulsan samples can be further dialyzed against ammonium bicarbonate and freeze-dried prior to use in surfactant packages.
• Acinetobacter calcoaceticus NS-1 (NRRL B-15847) was grown in a fermentor on ethanol medium under conditions similar to those described in U.S. Patent No. 4,395,354. Both whole broth and enzyme-treated whole broth were used to formulate surfactant packages.
• Acinetobacter calcoaceticus strains NS-4 (NRRL B- 15848), NS-5 (NRRL B-15849) , NS-6 (NRRL B-15860) and NS-7 (NRRL B-15850) were grown for 3 days in shake flask cultures in 2% ethanol medium as described in U.S. Patent No. 4,395,354.
• Enzyme-treated whole broth samples were prepared from the NS-4, NS-5 and NS-7 cultures.
• Enzyme-treated supernatant samples were prepared from NS-4, NS-5, NS-6 and NS-7 cultures. These preparations were also used to formulate surfactant packages.
• Boscan crude oil is a heavy crude produced from the oilfields of western Venezuela.
• the paraffin, aromatic, sulfur and asphaltene content were determined by the methods described in Section 7.2.3.
• Ex-Flasher is a vacuum bottom resid having a softening point of 70-90°F.
• the paraffin, aromatic, sulfur and asphaltene content were determined by the methods described in Section 7.2.3.
• Viscosity versus temperature profiles were obtained by heating the oils to temperatures given in the tables VII-XIII and measuring viscosities in a Rheo at 30 rheometer (Contraves AG) , at an approximate shear rate of 30 sec. " .
• the paraffin, asphaltene and aromatic contents of the sample hydrocarbons were obtained by a method in which the hydrocarbons are dispersed in n-heptane, the asphaltenes removed by filtration and the remaining components separated based on their solubilities in n-heptane and methylene chloride.
• the asphaltene fraction (the precipitate) is filtered from a dispersion of the hydrocarbon in n-heptane.
• the paraffin fraction is that portion soluble in n-heptane.
• the aromatic fraction is that portion soluble in methylene chloride, but not in n-heptane.
• the materials used are as follows: an analytical balance, accurate to 0.1 milligram (mg) , a blender (Osterizer Galaxy 14) and blades fitted to a 500 ml Mason jar, preweighed Whatman #1 paper, filter funnel, rotary evaporation apparatus, a 500 millimeter (mm) burette-type chromatography column, tared collection flasks, reagent grade methylene chloride, n-heptane (99 mole percent) and alumina adsorbent.
• the alumina was activated by heating it in an oven at 310°C for 12-14 hours.
• the alumina was cooled in a dessicator and stored in a tightly capped bottle prior to use. Chromatography columns packed 3/4 full were used.
• Hydrocarbon samples of 1-2 g were quantitatively added to Mason jars containing 100 ml of n-heptane. After blending for 1-2 minutes at maximum speed, the jar and its contents were washed with an additional 100 ml of n-heptane. The dispersed sample was filtered through Whatman #1 paper and the filtrate colected into Erlenmeyer flasks. After introduction of the filtrate to the column, the effluent was collected into a tared evaporation flask. When n-heptane was completely eluted, 200 ml of methylene chloride was added to the column and the eluted material collected into another tared evaporation flask until the column ran dry.
• the eluting solvents were removed using a rotating vacuum evaporator at temperatures appropriate to the solvents.
• the furnace fuel intake line is equiped with a Micro-Motion model C50 mass flow meter which can accurately measure fuel flow independent of viscosity. Just downstream of this meter, instrumentation which monitors fuel temperature and pressure is present, providing a continuous 5 record of these parameters during operation.
• Furnace exhaust gases are continuously monitored using a Perkin-Elmer Multiple Gas Analyzer (MGA) model 1200, a mass spectrometer which continuously samples and monitors 0 the exhaust for N_, 0_, S0_, H-0, and C0_.
• MAA Perkin-Elmer Multiple Gas Analyzer
• the assembly is also equipped with instrumentation which can monitor CO, NOX, and particulates within the exhaust gases.
• Sulfur dioxide SO removal efficiency is determined by measuring the baseline SO- concentration from produced by fuel being examined using the Perkin-Elmer Multiple Gas Analyzer. Comparisons were then made with the S0_ emissions observed during combustion the fuel containing various sulfur sorbents. For these comparisons, all SO concentrations were corrected to the "equivalent" concentration which would be observed if the exces burner was 3%, using the following conversion:
• [SO_] is the observed SO concentration and [0-] is the excess concentration of oxygen (i.e. that above the ambient air concentration) , both in volume precent.
• % removal The percent of SO- reduction observed when a sorbent additive is present, called % removal, is calculated by the following formula:
• [SO_] is the observed S0 2 concentration for each fuel or fuel/sorbent mixture at each condition examined.
• the removal efficiency (%RE) is determined by calculating the ratio of the (observed) % removal/the theoretical sulfur binding capacity of the sorbent (assuming it reacted stoichiometrically) and dividing this number by the % sulfur in the fuel, i.e.:
• % RE % Removal/% S stoich % S fuel
• Ex-Flasher (see section 7.2.2. supra) was tested as preatomized fuel having a 70/30 hydrocarbon to water ratio.
• the aqueous phase contains 0.125% of Kelco K1A112 biopolymer and a surfactant package, is present at a level of 1/250 parts oil.
• the surfactant package is comprised of the following:
• the “analysi.s” % was measured by a quanti.tative S-assay prior to combustion; the “theoretical” % was calculated from the measured SO- observed during combustion.
• analysis % is calculated based on the % S obtained in the analysis assuming 100% conversion to SO-.
• % Re-CaAc numbers provide the calcium utilization efficiency, assuming that all the CaAc present is utilized at 100% Stoichiometric efficiency.

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