MIXTURE FOR SUPPLYING A BOILER OR A DIESEL ENGINE, COMPRISING DIESEL FUEL OR HEATING OIL AND ESTERS AND ALKANES FROM THE TRANSFORMATION OF BIOMASS

Abstract

The goal of the invention is a mixture of liquid fuels for boilers or diesel engines with particular chain length esters and alkanes, and use thereof for reducing particle and nitrogen oxide emissions during operation of the boilers or diesel engines.

Claims

1. A mixture intended to supply a boiler or diesel engine comprising: at least one liquid fuel for boiler or a diesel engine fuel chosen among diesel fuel or domestic fuel oil; and at least one biosourced ester where the chain length is included between 8 and 14 carbon atoms incorporated in the fuel; and at least one biosourced alkane where the chain length is included between 8 and 14 carbon atoms, incorporated in the fuel; and wherein the incorporated ester(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture and where the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture.

2. The mixture according to claim 1 characterized in that the ester(s) with chain length included between 8 and 14 carbon atoms represent between 5% and 50% of the volume of said mixture.

3. The mixture according to claim 1, characterized in that the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 5 and 50% by volume of said mixture.

4. The mixture according to claim 1, characterized in that the incorporated alkane(s) with chain length included between 8 and 14 carbon atoms in the mixture are alkanes obtained by Kolbe electrolysis of volatile fatty acids coming from anaerobic fermentation of biomass or alkanes coming from the biomass by gasification and Fischer-Tropsch synthesis.

5. The mixture according to claim 1, characterized in that ester(s) with chain length included between 8 and 14 carbon atoms in the mixture are esters in which the acid part is obtained from volatile fatty acids coming from anaerobic biomass fermentation and esterification by an alcohol.

6. The mixture according to claim 1, characterized in that it comprises at least one additional additive that can improve the cetane number and/or reduce of particle emissions and/or reduce nitrogen oxide emissions by the boiler or diesel engine during operation.

7. The mixture according to claim 1, characterized in that it comprises at least one additive capable of improving the cold resistance and/or viscosity.

8. A process for production of a mixture according to claim 1, characterized in that it consists of incorporating in at least one liquid boiler fuel or diesel engine fuel chosen among diesel fuel or domestic fuel oil: at least one biosourced ester where the chain length is included between 8 and 14 carbon atoms; and at least one biosourced alkane where the chain length is included between 8 and 14 carbon atoms; and wherein in a way that the incorporated ester(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture and where the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture.

9. A use of a mixture according to claim 1 to supply a boiler or a diesel engine.

10. The use according to claim 9 in a boiler or diesel engine for reducing the particle emissions during operation of the boiler or engine.

11. The use according to claim 9 in a boiler or diesel engine for reducing the nitrogen oxide emissions during operation of the boiler or engine.

12. The use according to claim 9 in a diesel engine for improving the cetane index of the fuel.

13. The use according to claim 9 in a boiler or diesel engine for wherein other additives are added for improving the cetane number or enhancing the reduction of particle or nitrogen oxide emissions.

14. The use according to claim 9 in a diesel engine wherein other additives are added for improving the cold resistance and/or viscosity.

15. The use according to claim 9 in a fixed diesel engine or diesel engine installed in transportation vehicles or boats or worksite heavy equipment or agricultural equipment or small domestic equipment.

Description

DETAILED DESCRIPTION

[0033] The invention therefore aims for a mixture intended to supply a boiler or diesel engine, comprising: [0034] at least one liquid fuel for boiler or diesel engine fuel chosen among diesel fuel and domestic fuel oil; and [0035] At least one biosourced ester where the chain length is included between 8 and 14 carbon atoms incorporated in the fuel; and [0036] At least one biosourced alkane where the chain length is included between 8 and 14 carbon atoms, incorporated in the fuel;

[0037] Where the incorporated ester(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture, preferably between 5 and 50%, and where the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture, preferably between 5 and 50%.

[0038] The incorporated ester(s) with chain length included between 8 and 14 carbon atoms present in the mixture can be chosen among any ester with this size. It can preferably involve ethyl hexanoate (C8), butyl butyrate (C8), butyl valerate (C9), butyl hexanoate (C12) and/or butyl caprylate (C14). Preferably, it does not involve esters of higher fatty alcohols, meaning alcohols obtained from vegetable oil fatty acids that were reduced for example by hydrogenation and that are combined with a short acid such as formic acid or acetic acid.

[0039] The incorporated alkane(s) with chain length included between 8 and 14 carbon atoms present in the mixture can be chosen among the alkanes with this size (branched or unbranched). It can preferably involve decane, dodecane and tetradecane.

[0040] According to the invention, by specifically selecting esters with a chain length included between 8 and 14 carbon atoms, it will advantageously be possible to continue meeting all current specifications for diesel engine fuel and boiler fuel, including at an incorporation level between 1 and 8%, except for the maximum level of esters because the esters produced that way are not the methyl esters of fatty acids meeting the standard EN14214. Thus, according to a variant, the invention targets the mixture such as previously described in which the ester(s) with chain length included between 8 and 14 carbon atoms represent between 1% and 8% of the volume of said mixture. This mixture can be dispensed as an ordinary fuel in all distribution pumps.

[0041] Further, the esters used according to the invention can also be used at higher levels. Thus, according to another variant, the invention targets the mixture such as previously described in which the incorporated ester(s) with chain length included between 8 and 14 carbon atoms represent between 8% and 80% of the volume of said mixture, which will be distributed either as an ordinary fuel if it is approved for that use, or as a fuel for captive transport fleets.

[0042] Preferably, the ester(s) with chain length included between 8 and 14 carbon atoms present in the mixture are esters of biosourced origin obtained from volatile fatty acids coming from anaerobic biomass fermentation and esterification by an alcohol.

[0043] Likewise, a mixture is preferred in which the incorporated alkane(s) with chain length included between 8 and 14 carbon atoms present in the mixture are alkanes obtained by Kolbe electrolysis of volatile fatty acids coming from anaerobic fermentation of the biomass such as described in the application WO2014/170603 or from the biomass by gasification and Fischer-Tropsch synthesis.

[0044] The mixture according to the invention, in addition to the fuel, esters and alkanes of specific chain length, could contain at least one additional additive for improving the cetane number and/or increasing the reduction of particle emissions and/or reducing nitrogen oxide emissions by the boiler or diesel engine during operation thereof. It can involve for example tetranitromethane.

[0045] Other additives can be added to improve other functionalities of the mixture like cold resistance, viscosity, etc.

[0046] The mixture according to the invention can be obtained by other conventional techniques of the person skilled in the art. Preferably, it is obtained by a simple mixing of the constituents in a single tank or the mixing of two fluids in a single pipe. In most countries, such a mixing would have to be done under the control of the Customs Department.

[0047] The invention specifically targets a process for production of a mixture according to the invention such as previously described, which consists of incorporating in at least one liquid boiler fuel or diesel engine fuel chosen among diesel fuel or domestic fuel oil: [0048] At least one biosourced ester where the chain length is included between 8 and 14 carbon atoms; and [0049] At least one biosourced alkane where the chain length is included between 8 and 14 carbon atoms.

[0050] In a way that the incorporated ester(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture and where the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture.

[0051] Preferably, the mixing is done at a temperature included between 10 and 50 C. in a stirred tank or in a device where the various components are mixed by crossflow mixing.

[0052] Surprisingly and advantageously, with the mixture according to the invention, which incorporates specific esters and alkanes in diesel engine fuels or in boiler fuels, a very significant reduction of particle emissions is possible without a worsening of other emissions in particular nitrogen oxides and other emissions such as CO, HC, etc. The level of reduction of the particles by mass and count is of order twice the rate of incorporation (30% to 40% for 20% incorporation; 60% to 80% for 40% incorporation; and 80% to 90% for 50% incorporation), which constitutes a considerable advantage for reducing particle emissions in cities. Since there is a parallel reduction for particle mass and count, this process does not enhance smaller particles which are more dangerous.

[0053] The invention therefore specifically targets the use for supplying a boiler or diesel engine with a mixture comprising: [0054] At least one liquid fuel for boiler or a diesel engine fuel chosen among diesel fuel or domestic fuel oil; and [0055] At least one biosourced ester where the chain length is included between 8 and 14 carbon atoms incorporated in the fuel; and [0056] At least one biosourced alkane where the chain length is included between 8 and 14 carbon atoms, incorporated in the fuel;

[0057] The incorporated ester(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture and where the incorporated alkane(s) with a chain length included between 8 and 14 carbon atoms represent between 1% and 80% by volume of said mixture.

[0058] In particular, the invention targets the use of the mixture in a boiler or diesel engine for reducing the particle emissions and/or reducing the nitrogen oxide emissions during operation thereof. Advantageously, the cetane number of the fuel can also be improved with the invention.

[0059] The mixture according to the invention can be used in any liquid fuel boiler and in any diesel engine, in particular in a fixed diesel engine or diesel engine installed in transportation vehicles or boats or worksite heavy equipment or agricultural equipment or small domestic equipment such as lawnmowers or rototillers.

[0060] In addition to the mixture according to the invention, at least one additive can be added in the boiler and/or the engine, where the additive is capable of improving the cetane number and/or improving the reduction of particle emissions and/or reducing the nitrogen oxide emissions by the boiler or the diesel engine during operation thereof, and/or at least one additive capable of improving other functions of the mixture like cold resistance, viscosity, etc.

Examples 1-5

[0061] The invention is now illustrated by examples of mixtures according to the invention and emission test results on an engine test bench showing their effectiveness.

[0062] The composition of the various mixtures tested is described in the table (examples 1 to 5 with various load rates which represent the number of RPMs of the engine compared to the nominal number of revolutions). These mixtures are obtained by simple mixing of components in jugs with manual agitation.

[0063] The measurements are done at the exhaust of a Renault brand car engine by a Horiba 9100 (CO, CO2, O2, HC and NOx) and PPS PEGASOR particle analyzer.

[0064] The results obtained are shown in the following table:

TABLE-US-00001 Fuel % load mg/m3 N/cm3 Smoke CO NOx Reference diesel 20 3.9 19,000 0.3 700 85 30 34 170,000 2.8 810 116 40 43 220,000 3.9 1600 238 45 20 95,000 2 830 370 60 1.5 7,000 0.4 220 1300 EXAMPLE 1: INVENTION 20 3.6 18,000 0.25 764 63 Diesel + 10% decane + 20% butyl butyrate 30 13 62,000 1.35 540 114 Substantial drop of particles (31% by 40 9 42,000 0.92 343 331 count) 45 7 32,000 0.75 350 575 Without substantial worsening of NOx 60 1.8 8,500 0.23 475 1214 EXAMPLE 2: INVENTION 20 2.3 11,000 0.17 800 55 Diesel + 20% decane + 20% butyl 30 15 70,000 1.65 575 100 hexanoate 40 19 88,000 2.2 920 222 Substantial drop of particles (48% by 45 18.5 90,000 2.35 880 235 count) 60 1.3 6,000 0.29 270 1168 Slight drop (15%) of NOx EXAMPLE 3: INVENTION 20 3.2 15,000 0.23 870 41 Diesel + 20% decane + 20% butyl butyrate 30 15.5 74,000 1.6 591 92 Substantial drop of particles (36% by 40 31 148,000 3.5 1806 160 count) 45 19 82,000 2.12 960 240 Slight drop (19%) of NOx 60 1.5 6,800 0.32 465 1186 EXAMPLE 4: INVENTION 20 0.3 1,600 0.03 1240 72 30% diesel + 20% decane + 50% butyl 30 3 14,000 0.22 530 122 butyrate 40 5 23,000 0.34 337 228 Large drop of particles (88% by count) 45 4.5 21,000 0.42 347 300 Slight drop (11%) of NOx EXAMPLE 5: INVENTION 20 1 5,000 0.04 1218 50 diesel + decane + butyl 30 5.5 28,000 0.41 550 101 butyrate 40 13 62,000 1.00 566 182 Large drop of particles (74% by count) 45 7 35,000 0.53 380 263 And substantial drop (27%) of NOx

[0065] These results show that the alkanes do not have a significant favorable impact on the particle emissions, whereas the esters and alkanes together are unexpectedly able to very significantly reduce particles more or less proportionally to the ester level (drop of particles of order twice the level of incorporated esters) at the same time as a significant drop of NOx. In this respect, example 5 is very persuasive.

[0066] The other parameters (CO, HC) are not degraded. There is even a substantial drop of the CO. By adjusting the levels of esters and alkanes, it is thus possible to optimize emissions from diesel engines.