FI95391B - New fuel mixture - Google Patents

Description

1 95391

New fuel mixture

The invention relates to a fuel mixture containing biological oil and to the use of such a fuel mixture as fuel in engines and heat / power plants.

Conventional liquid fuels for internal combustion engines consist of hydrocarbon mixtures and are obtained mostly from petroleum. The dwindling crude oil reserves have increased the demand for fuels in which at least 10 hydrocarbons have been partially replaced by renewable fuels such as vegetable or animal oils. By greatly reducing the share of non-biodegradable hydrocarbons, the risks of pollution caused by oil and other disasters are also reduced.

In addition to solid fuels, the aim is to produce liquid fuels for the transport sector and for the production of heat and electricity from various biomasses. 15 Some development programs have set a target of a 5% share of biofuels in the transport sector in total transport fuel consumption, corresponding to an annual use of around 5-10 megatons. The main applications are gasoline additive components, ethanol or methanol and ethers, ethyl t-butyl ether and methyl t-butyl ether. For diesel engines, the goal is to produce biofuels mainly from rapeseed or, in the Nordic countries, from tall oil from pulp cooking.

DE 24 41 737 describes fuel mixtures for gasification internal combustion engines consisting of a mixture of hydrocarbons and a mixture containing lower alcohol, water and possibly a small amount of vegetable oil which acts as a compatibilizer.

DE-31 49 170 and DE-31 50 988 disclose diesel fuels in which up to 90% of the hydrocarbons have been replaced by alkyl fatty acid esters of vegetable oils, the fuel mixture also containing a lower alcohol. In this case, however, it has been necessary to completely convert the vegetable oils into alkyl fatty acid esters, in particular methyl fatty acid esters, which on the one hand entails high costs and on the other hand the formation of glycerol waste which is difficult to recover.

Attempts have also been made to use non-esterified vegetable oils, such as rapeseed oil, as fuels in internal combustion engines. U.S. Pat. No. 4,359,324 discloses diesel fuel oil consisting of 25-75% butyl alcohol and 75-85% vegetable oil. U.S. Pat. No. 4,557,734 again discloses a diesel oil 95391 2 consisting of vegetable oil, methanol or ethanol and a straight-chain octanol.

DE-4 116 905 discloses a fuel mixture comprising 60-88% by volume of at least one vegetable and / or animal oil, 6-20% by volume of at least one straight-chain or branched 5 aliphatic monoalcohol having 1-5 carbon atoms and 6-20% by volume. volume% gasoline.

WO 83/00344 discloses an internal combustion engine fuel which is a mixture of oil, alcohol and tall oil. Tall oil acts as a balancing agent for oil and alcohol. the oil is preferably a fatty oil or diesel oil, and the alcohol is preferably ethanol or methanol. The preferred amount of tall oil is at least 15% by volume.

10 In the light of the foregoing, it is therefore known that rapeseed oil cannot be used as such in diesel engines, since that dirt, in particular, scorches the nozzles after 500 to 1500 hours of operation. The problem has been avoided with specially designed motors, e.g. Elsbett engine, or by chemically modifying the physical properties of rapeseed oil close to ordinary diesel oil, mainly by the above esterification. Επί 5 twin engines are about double the cost of modifying the engine's injection equipment and combustion chambers and introducing a higher temperature to prevent scaling. Usually the scaling is due to incomplete combustion of the triglyceride structure of the vegetable oil and poor dripping of the oil in the nozzles. For certain grades of oilseeds, the viscosity of the oil also increases as the outside temperature 20 decreases, making use under winter conditions out of the question.

The object of the present invention is to provide a fuel which consists essentially of a naturally renewable material. In this case, special efforts are made to utilize vegetable and / or animal oil. In particular, the invention relates to a fuel which, due to its chemical and physical properties, is suitable for conventional use, i.e. for conventional vehicles, propulsion and power plant machines, and for conventional combustion equipment for heat production. The invention also seeks to provide a biodegradable fuel suitable as a fuel for current types of diesel engines. The fuel according to the invention must also be as environmentally friendly as possible.

30

The above-mentioned objects have now been achieved with a biofuel-containing fuel mixture which is mainly characterized by what is stated in the characterizing part of claim 1. It is thus realized that a more useful fuel mixture is obtained if it comprises 3 95391 a) 5-100% by weight of the fuel mixture of a biocomponent mixture containing aj) about 50-95, preferably 70-90%, by weight of the biocomponent mixture of at least one vegetable or animal oil, and SL2) about 5-50, preferably 10-30%, by weight of the biocomponent mixture of a C1-C6 alkyl ester of a fatty acid and / or rosin acid or a mixture thereof, and b) 0-95% by weight of a fuel of a hydrocarbon component.

The solution according to the invention was reached when it was found that by esterifying tall oil or rapeseed oil, which consists mainly of a mixture of fatty acids (and resin-10 acids, tall oil), and adding the esterified tall oil or nitric oil to the fuel oil, in this case which did not show diesel engine scaling or a sharp increase in viscosity at lower temperatures.

Thus, the fuel mixture according to the invention may contain 5-100% by weight of said bio-oil and a biocomponent mixture consisting of a fat and / or resin ester. The lower concentration limit comes into play when said biocomponent mixture is used as an additive to the hydrocarbon component of the fuel mixture or, for ecological reasons, it is desired to include environmentally friendly components in conventional hydrocarbon fuels. The upper limit of the concentration range is set to 100% by weight, which means that in this case the fuel mixture is completely said biocomponent mixture. Since the invention is based on the realization that the C 1 -C 4 alkyl ester of a fatty acid and / or rosin acid eliminates the disadvantages of conventional bio-oils, there is nothing to prevent the use of a completely biological substance as fuel.

Although, on the basis of the foregoing, said biocomponent mixture can be used over a very wide concentration range, it has been found advantageous if the fuel mixture according to the invention comprises about 10-60% by weight of said biocomponent mixture. It is preferred that the fuel mixture comprises 40-90% by weight of said hydrocarbon component. In this case, tall oil acts as a coordinating agent between the hydrocarbon fuel and the bio-oil, thus forming a synergistic thematic mixture.

The invention was realized by examining how the behavior of rapeseed oil as a fuel could be improved. Since rapeseed oil is a typical vegetable oil structurally very closely resembling other bio-oils, the invention was extended to all bio-oils as a component aj. All major bio-oils (both vegetable and animal oils) are glycerol fatty acid esters, i.e. glycerides, mainly triglycerides, and are based mainly on saturated C4-C26 fatty acids such as butyric acid, caproic acid, caprylic acid, capric acid, capric acid acid, palmitic acid, stearic acid, arachidic acid, behenihappo lignoceric and cerotic acid, such monounsaturated CIO-C26 fatty acids, such as obtusiliinihappo, kaproleiinihappo, lauroleic, fyseteerihappo, Petroselli-5 acid, oleic acid, vaccenic acid, gadoleic acid, brassidic, ketoleiinihap acid, erucic acid, selacholeic acid, and xymenic acid, to polyunsaturated C 18 -C 24 fatty acids such as linoleic acid, linolenic acid, eleostearic acid, parinaric acid, clupanodonic acid and castoric acid. Substituted mainly C18 fatty acids such as ricinoleic acid, fatty acid and chaulmo-ogra-10 acid, as well as synthetic fatty acids. See. Ullmanns Encyklopädie der techni- schen Chemie, 3rd edition (1956), part 7, pp. 454-563, which is incorporated herein by reference. Although there may be slight differences in structure and composition, the chemical composition and structure of bio-oils are so uniform that the invention applies to all bio-oils found in the art. The very close structure of bio-oils is evident in 15 mm. from Kirk-Othmer, 3rd Edition (1983), John Wiley & Sons, Vol. 23, pp. 717-741, which is incorporated herein by reference.

It is preferable if biocomponent al is a vegetable oil such as cotton seed oil, hamppuölky, rapeseed oil, peanut oil, pyökinydinöljy, Chinese wood oil, soi-jaöljy, sunflower oil, rapeseed and canola oil, Poppy, sesame oil, olive oil, 20 oitikikaöljy, corn oil, safflower oil, mustard seed oil, palm oil , palm kernel oil, perilla oil, coconut oil, linseed oil, castor oil, etc. Due to the very close properties of triglyceride molecules, these oils are very similar in chemical and physical (density, viscosity) properties.

The preferred bio-oil to be used in the fuel mixture according to the invention, i.e. component ai, is rapeseed oil. Rapeseed oil is also a triester or glycerol of glycerol, in which various fatty acids, mainly palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, are esterified in glycerol. Free fatty acids in rapeseed oil and no other vegetable oils are just inside. Most of the fatty acids contained in rapeseed oil have 18 carbon atoms, oleic acid being the most, linolenic acid 3 0 the second most, and alpha-linolenic acid the third most.

Rapeseed oil is produced in small oil presses in such a way that the seeds are usually treated with a spray press without an external heat source, so that the temperature does not rise above 40 ° C. The product is purified by sedimentation and is called cold pressed rapeseed oil. In large oil mills, on the other hand, refining is carried out using 35 hot-pressing techniques according to the following steps: 1 95391 1) the seeds are pre-pressed (steam heating 80-90 ° C), eg the residue is extracted with n-hexane = "extracted oil", and 3) the hexane is distilled off and the oil is mixed with filtered "pre-pressed oil" = "crude rapeseed oil".

crude rapeseed oil produced by oil pressing can be further refined. Cold-pressed rapeseed oil can be used as it is, purified with water and / or phosphoric acid or purified with sulfuric acid. Large oil mills use the same 10 refining methods to obtain the following products: 1) crude hot-pressed rapeseed oil, 2) water-purified rapeseed oil, 3) water- and acid-purified (superdegummed) rapeseed oil, 4) partially refined (neutralized) rapeseed oil, 5. The resulting rapeseed oil should be stored protected from light and heat and preferably from oxygen in the air.

The second component a2 of the biocomponent mixture a of the fuel mixture of the invention is a C 1 -C 6 alkyl ester of a fatty acid and / or rosin acid or a mixture thereof. The alkyl ester can thus be a methyl, ethyl, propyl, butyl, pentyl or hexyl ester. When lower alcohol esterified tall oil or rapeseed oil was added to the bio-oil in the experiments, a mixture was formed which lacks the disadvantages associated with the use of pure bio-oil in engines and burners, such as scaling and high low temperature viscosity. Thus, it has been found experimentally that some, some or all of the components of esterified tall oil or rapeseed oil improve the utility of bio-oil as a fuel.

It appears from the literature Ullmanns Encyklopädie der technischen Chemie, third edition (1965), part 16, pp. 650-656, which is incorporated herein by reference, that a typical Nordic crude tall oil consists of approximately 40% rosin acids, 45% fatty acids, 12% unsaponifiable matter and 3% oxidized acids. Rapeseed oil, on the other hand, consists of a triester of glycerol and fatty acids, cf.

above. As the unsaponifiable matter is also not esterified, it is clear that the positive effect on the fuelability of the bio-oil is due to one or more ras-30 waxic acids and possibly also one or more rosin acids. It is also clear that since said resin and fatty acids are present elsewhere than in tall oil and fatty acids other than in rapeseed oil, their other addition alone or together in the form of their C 1 -C 6 alkyl ester to the bio-oil improves the bio-oil in the same way as C 1 -C 4 alkyl esterified tall oil. or rapeseed oil. Therefore, it is completely natural to define the biocomponent mixture a of the fuel mixture according to the invention so that it contains, in addition to the bio-oil ai, a C1-C6 alkyl ester of fatty acid and / or rosin acid or a mixture thereof as component 2, thus ensuring that the idea of the invention is protected. It should be noted that the fatty acid fraction of tall oil is very similar to the fatty acid fraction of soybean oil. It is therefore natural that the patent would then also protect the C1-C8 alkyl esters of other vegetable oils, such as soybean oil, as a component & 2 ·

Typical fatty acids of component & 2 are the fatty acids mentioned above in connection with the bio-oil, in particular oleic acid, linoleic acid, palmitic acid, stearic acid and linoleic acid. Typical resin acids according to the invention are various types of primer acids and abietic acids. There are resin acids e.g. discussed in Ullmanns Encyklopä-die der technischen Chemie, 3rd edition, part 8, pp. 400-417, which is incorporated herein by reference. It should be noted that resin acids are not only present in tall oil, but also in other wood processing and the like.

It is preferred that component a2, i.e. the C 1 -C 6 alkyl ester of the fatty acid and / or rosin acid, is a C 1 -C 6 alkyl ester of the tall oil fatty acid component and / or the rosin acid component, or the rapeseed oil fatty acid component, preferably ethyl or methyl ester. Although the invention relates to the use of both individual fatty acids and / or rosin acids in combination with bio-oil to improve the fuel mixture, it is nevertheless advantageous and economical to utilize their naturally occurring mixtures. According to one embodiment, the mixture of a C 1 -C 6 alkyl ester of a fatty acid and / or a rosin acid is a C 1 -C 6 alkyl esterified tall oil, more preferably an ethyl or methyl esterified tall oil, i.e. an ethyl tall oil ester or mes-. styline pine oil ester, most preferably methyl esterified tall oil, i.e. methyl pine oil ester.

In another embodiment, the mixture of a C 1 -C 4 alkyl ester of a fatty acid is a C 1 -C 4 alkyl esterified (transesterified) bio-oil, such as fish oil, cottonseed oil, peanut oil, soybean oil, sunflower oil, rapeseed oil, rapeseed oil, rapeseed oil, rapeseed oil, rapeseed oil, rapeseed oil , palm kernel oil, coconut oil, linseed seed oil, castor oil and the like, preferably C 1 -C 6 alkyl esterified rapeseed oil, more preferably ethyl or methyl esterified rapeseed oil, i.e. ethyl rapeseed oil ester or methyl rapeseed oil ester, methyl rapeseed oil ester, rapeseed oil ester

As mentioned above, the fuel mixture according to the invention may contain only 35 biocomponent mixtures, but it is advantageous if the biocomponent mixture is mixed with 7 95391 hydrocarbon components. The hydrocarbon component, i.e. the above-mentioned component b, can in principle be any hydrocarbon suitable for fuel or a mixture thereof, but for practical reasons it is preferably a hydrocarbon component obtained by refining petroleum, such as light fuel oil or diesel oil. The most preferred hydrocarbon component used in the invention is diesel oil which, when mixed with biocomponent a, enables the biocomponent mixture according to the invention to be used as diesel fuel. According to one aspect of the invention, the patent protection therefore relates to the use of the fuel mixture described above as a fuel in internal combustion engines and in particular in diesel engines. According to another embodiment of the invention, the fuel-10 mixture described above can be used as a substitute for fuel oil in the production of heat and electricity. In this case, the fuel mixture according to the invention essentially replaces light fuel oil.

The following is an example to illustrate the invention.

Example

The fuel mixture, to which 20% by weight of cold-pressed rapeseed oil, 5% by weight of 15 methyl pine oil ester and 75% by weight of reformulated diesel oil were added, was tested in the Peugeot diesel engine nozzle card test according to CEC PCF-26. The test period was 6 hours during which no scaling was observed in the engine injection system. The result was a 79% degree of soiling when the mouthpiece needle was raised 0.1 mm. The degree of fouling with diesel fuel alone was 87%, which means that the result with vegetable oil blend-20 was better than with conventional diesel fuel. The mixture containing 20% cold pressed rapeseed oil and 5% rapeseed oil methyl ester had a fouling rate of 71%.

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Claims (9)

95391 A fuel mixture comprising a biological oil, characterized in that it comprises a) 5-100% by weight of the fuel mixture of a biocomponent mixture comprising aj) about 50-95% by weight of the biocomponent mixture of at least one vegetable or 5 animal oil a2) about 5-50 % by weight of the biocomponent mixture of a C 1 -C 6 alkyl ester of a fatty acid and / or rosin acid or a mixture thereof, and b) 0-95% by weight of a hydrocarbon component of the weight of the fuel mixture. Fuel mixture according to claim 1, characterized in that it comprises 10 to 60% by weight of said biocomponent mixture. Fuel mixture according to claim 1 or 2, characterized in that it comprises 40 to 90% by weight of said hydrocarbon component. 15 Fuel mixture according to Claim 1, 2 or 3, characterized in that component ai is a fatty acid ester of glycerol of vegetable origin or a mixture thereof, most preferably rapeseed oil. Fuel mixture according to one of the preceding claims, characterized in that component a2 is a C 1 -C 6 alkyl ester, preferably an ethyl or methyl ester, most preferably a methyl ester of a fatty acid component and / or a rosin acid component of tall oil or rapeseed oil. Fuel mixture according to one of the preceding claims, characterized in that the mixture of a C 1 -C 6 alkyl ester of a fatty acid and / or a rosin acid is a C 1 -C 6 alkyl esterified tall oil, preferably an ethyl or methyl esterified tall oil, i.e. a ethyl ester tall oil or methyl tall oil ester. 30 Fuel mixture according to one of Claims 1 to 5, characterized in that the mixture of a C 1 -C 4 alkyl ester of a fatty acid is a C 1 -C 6 alkyl-transesterified bio-oil, preferably rapeseed oil, preferably ethyl- or methyl-interchangeable esterified . Fuel mixture according to one of the preceding claims, characterized in that the hydrocarbon component b is a light fuel oil or, preferably, diesel oil. 95391 Use of a fuel mixture according to any one of the preceding claims as a fuel for internal combustion engines and as a fuel oil for the production of heat and electricity, preferably as a fuel for diesel engines. 5