It is known that the emission of polluting gases of every stoker working with fossil combustible strongly inhibit the applicability thereof. The main problem is caused by the presence of residual hydrocarbons, partially oxidised compounds thereof, and nitrogen oxides (hereinafter Ox). Out of the partially oxidised exhausts the most important is CO (carbonmonoxide), and the particularly detrimental aldehides and other hydrocarbon derivatives.

According to the state of the art there have been several attempts in order to reduce the emissions.

According to US 5,302, 111, US 5,522, 721 enriched and poor fuel zones are prepared by the use of pulsed burning, increasing the heat transmission and thereby reducing NOx formation as the burning does not take place stochiometrically. On an average a 60% NOx reduction could be thus achieved, The energy saving greatly depends on the type of the burner, on the structure of the flame channel and on the adjustment of the oscillation.

In EP 1,213, 459 an exhaust emission control system, i. e. a catalyst for an internal combustion engine having an exhaust system is disclosed. The control system-may include an exhaust gas purifying device provided in the exhaust system and an oxygen concentration sensor provided downstream of the exhaust gas-purifying device. This catalyst improves the characteristics of the flue-gas. Its disadvantage is that several devices have to be installed into the exhaust system.

The SNCR (Selective Non-Catalytic Reaction) technology is an expensive solution to reduce NOx, when an ammonia containing additive is injected to the soot (600-900°C) and a further solution is the SCR (Selective Catalytic Reaction) when an ammonia containing additive is injected to the exhaust gas (250-350°C)

in the presence of a catalyst and pure oxygen and nitrogen are formed instead of NOx. The disadvantage of the former solution is that it's efficient only at higher temperature ranges, whereas the latter-is more expensive due to the necessity of a catalyst.

In W00210317 a low-emissions diesel fuel is disclosed comprising a catalyzed blend consisting of mainly surfactants, mainly methyl fatty acid esters.

The catalyzed blend is effective in lowering regulated emission pollutants. A disadvantage of this solution is that it can be used only for diesel motors and at the most a 50% reduction of NOx can be achieved unless further catalysts are used in the system.

According to US 2002083713 the invention contemplates a gas turbine engine compressor including a plurality of effervescent atomizers to inject a mixture of water and methanol into the compressor inlet. Injection of water and water containing mixtures has been known for a long time. Several practical problems may occur using this solution. By reducing the flame temperature, NOx is formed to a smaller extent, but the amount of the residual hydrocarbons is increased. A further problem may be when instead of the built up air a vapour of lower temperature reaches the compressor, which will start to sinter and thus the shovels may damage it and the efficiency of the equipment will be diminished.

According to US 6,458, 473 a thermal insulating ceramic layer coating system is disclosed for use in a turbine exposed to high temperature and mechanical loading to fix the ceramic layer by a metal bond on the surface of the equipment.

Thereby the warm components are protected from the heat load by a 25-150, um layer and from the erosion of pollutants included in the exhaust gas and the absorbed gas. The application of this invention is very expensive, the coating of the surface has to be regenerated regularly, requiring a breakdown and this is a disadvantage in case of continuously working or overloaded turbines.

According to US 5,282, 990 the fuel economy of an internal combustion engine can be improved by adding to the lubricating oil used to lubricate the crankcase of said engine a synergistic blend of amine/amide and ester/alcohol friction modifying agents, for example, by reacting (a) a carboxylic acid, such as oleic acid and/or isostearic acid with an amine, such as diethylene triamine or tetraethylene pentamine, and (b) glycerine monooleate and/or glycerine monoricinoleate.

The applicability of any additive is significantly reduced by injecting it together with the engine oil. It is particularly unsuitable for the protection of surfaces not being in contact with lubricating substances or in case of vaporized fuel for the fining of the grit.

US 4,492, 640 provides a compound effective as a friction reducer in lubricants and fuels, thus reducing the consumption of fuel. The compound is a boron derivative of a mixture of alkoxylated alcohols and hydroxysulfides.

If any sulphur containing substance gets into the soot, increased problems of corrosion and pollution occur.

CA2379798 is related to a fuel composition comprising a major amount of base fuel and at least 3 % w/w of an ester additive mixture derivable by reacting together either (a) (i) a saturated, aliphatic polyhydric alcohol having three or more primary alcohol groups, (ii) a C2-C15 saturated, aliphatic branched chain monohydric alcohol and (iii) a saturated, aliphatic C4-C10 dicarboxylic acid, or (b) a saturated aliphatic polyhydric alcohol having three or more primary alcohols grouped with a C6-C15 saturated, aliphatic straight chain or branched chain monocarboxylic acid, or (c) a C2-C15 branched chain saturated aliphatic alcohol with a saturated, aliphatic dicarboxylic acid having 6-10 carbon atoms. The ester additive has a boiling point >=150-C, a molecular weight >=200 and an oxygen content >=13 % by weight of said ester additive mixture. The additive significantly reduces particulate emissions from the exhausts of diesel powered engines.

This additive can be used only in diesel engines and does not contain any surface-protecting additive.

The present invention is based upon the recognition that by combining appropriate components the following surprising effects may be achieved: The surface stress and viscosity are reduced in case of liquid fuels.

Thereby the energy used for the atomization and feeding of the fuel can be reduced and the significantly reduced size of the particles delivered to the soot makes a complete burning possible in the soot during the available time. In this procedure the effect of the used esters play the main role.

A surface protection may be achieved in the soots, hindering the formation of NOx on the surface of the soot. It is often not taken into account, that the Cr and Ni content of the alloyed steels catalyses the NOx formation. One significance of

the additive is that upon the surface modifying activity of the following components of the additive the indirect contact of the hot exhaust gases with the catalysing surface is sterically hindered. The protection of the surface inhibits its corrosion at the high operating temperature. This effect is mainly due to the nitrogen containing organic compounds and acidic phosphates of the additive according to the invention by forming a binuclear complex on the surface. The fixation of this complex is ensured by any Cr, Fe, Al atom on the surface to be protected as a complex forming nucleus. The additive has to be continuously used because of the slow thermic degradation of the complex.

In addition to the above-mentioned surface protecting mechanism the reduction of the amount of NOx is also due to the fact that the reduced nitrogen containing radicals derived partially from the degradation of the complex and partially from the added organic compounds containing amino groups, getting into the soot result, reacting with the already formed NOx molecules in the formation of pure N2 and 02 instead of the polluting NOx. This is similar to the SNCR technology with the advantageous difference that no ammonia addition is required.

'The formed surface is simultaneously a heat-reflecting surface, resulting in the increase of thermodynamical efficiency. The same result is achieved when due to the shorter burning time needed due to the smaller particles the explosion periodical time is reduced and the angle of advance and the injection angle can be adjusted optimally. This means that the ratio of the fuel is drastically reduced, which is burnt below the upper dead centre of the piston, and thus it practically results in losses.

The above effects result not only in the reduction of the fuel consumption but also in the drastical reduction of the emission of polluting substances.

Especially the emission of partially oxidated aromatic, carcinogenic substances is considerably reduced.

The present invention relates to a fuel additive with reduced emission and modifying the surface, of reduced specific energy consumption and ensuring increased efficiency of the equipment to be used for explosion motors, for turbines heated with gaseous and liquid hydrocarbons and for heating equipments operating with every fossil fuel, comprising 80-99.5 % by volume of hydrocarbons boiling at 45-405 °C,

10-4-2 % by weight of acidic meta-, pyro-or orthophosphate in the form of an acidic alkali salt, 0.1-5. 5 % by volume of C8-C48 saturated or unsaturated fatty acid ester, preferably polyglycerol ester or a mixture thereof, and/or C8-C48 ethoxylated fatty acid ester containing 3 to 11 EO ethoxy units, preferably polyglycerol ester or a mixture thereof, and/or C8-C48 propoxylated fatty acid ester containing 2 to 11 PO propoxy units, preferably polyglycerol ester or a mixture thereof, 0.1-18 % by volume of C8-C45 ethoxylated saturated or unsaturated fatty acid ester, preferably polyglycol ester containing 4 to 15 EO units, 0.1-6 % by weight of basic nitrogen containing polyamine, and/or ethoxylated polyamine containing at least two basic nitrogens, and/or fatty acid diethanol amide, and/or C6-C40 saturated or unsaturated fatty acid polyester containing at least two basic nitrogens, and/or alkyl amine containing 1 to 5 amino groups.

The fuel additive according to the invention preferably contains as alkali phosphate dipotassium dihydrogen pyrophosphate, sodium metaphosphate, sodium-trihydrogen-pyrophosphate, potassium-dihydrogen-orthophosphate or sodium-dihydrogen-orthophosphate.

The fuel additive according to the invention preferably contains as ethoxylated polyglycol ester ethoxylated polyethylene glycol ester.

The fuel additive according to the invention preferably contains as ethoxylated polyglycol ester ethoxylated polypropylene glycol ester.

The fuel additive according to the invention preferably contains as ethoxylated polyglycol ester 8-45, preferably 16-18 carbon atoms and 4 to 15, preferably 10 EO units.

The fuel additive according to the invention preferably contains C16-C18 diglyceride ester having 2 to 8 PO units.

The fuel additive according to the invention preferably contains octylamin as an alkylamine.

The present invention is further related to a process for the reduction of the emission of polluting agents and the reduction of the specific consumption of fuel of explosion engines and turbines operating with gas and oil and heating

equipments operating with every fossil fuel, for the simultaneous surface protection of the soot and for the increase of the efficiency of the equipment, comprising adding to the soot the fuel additive according to the invention.

The invention is further directed to a process for the reduction of the emission of polluting agents and the reduction of the specific consumption of fuel of explosion engines and turbines operating with gas and oil and heating equipments operating with every fossil fuel, for the simultaneous surface protection of the soot and for the increase of the efficiency of the equipment, comprising admixing 80-99.5 % by volume of hydrocarbons boiling at 45-405 °C, 10-4-2 % by weight of acidic meta-, pyro-or orthophosphate in the form of an acidic alkali salt, 0.1-5. 5 % by volume C8-C48 saturated or unsaturated fatty acid ester, preferably polyglycerol ester or a mixture thereof, and/or C8-C48 ethoxylated fatty acid ester containing 3 to 11 EO ethoxy units, preferably polyglycerol ester or a mixture thereof, and/or C8-C48 propoxylated fatty acid ester containing 2 to 11 PO propoxy units, preferably polyglycerol ester or a mixture thereof, 0.1-18 % by volume of C8-C45 ethoxylated saturated or unsaturated fatty acid ester, preferably polyglycol ester containing 4 to 15 EO units, 0.1-6 % by volume of basic nitrogen containing polyamine, and/or ethoxylated polyamine containing at least two basic nitrogens, and/or fatty acid diethanolamide, and/or C6-C40 saturated or unsaturated fatty acid polyester containing at least two basic nitrogens, and/or alkylamine containing 1 to 5 amino groups.

As the first step of the process according to the invention the nitrogen containing components are preferably reacted with one of the phosphates.

The details of the present invention are further illustrated with the following examples, which serve merely for illustration and do not restrict the scope of the claim of the invention.

Example 1 The additive was added to the fuel gas of the turbine by an atomizer fixed on the fuel gas tube of the 8 MW industrial gas turbine in the ratio of 80-120 ml additive [1 % by weight of sodium metaphosphate, 2,4 % by weight of fatty acid

polyglycerol ester (E 475 emulgeator, Hungarian Food Book), 4 % by volume of ethoxylated polyamine (Stokomin Moi 171, BGB Stockhausen GmbH) and 1, 5% by volume of ethoxylated fatty acid ester (Ipamin SG P6, Egyesult Vegyimuvek Rt), and the remainder 1,5% of desulphurized petrol] per 100 nm3 fuel gas. Prior to and following the measurement HORIBA and MSI multichannel flue-gas analyzing equipment and sorption tubes were used to measure among others the CH and NOx emission of the turbine. The emission data obtained prior to and following the feed of the additive can be seen in Table I, showing that in case of equal capacity the emission of CH and NOx was reduced. During measurement the turbine was operating at the same capacity (4, 57<X<4, 77). In column"NOx"the values obtained at the site are shown, column"NOx corr. "contains the values compensated with the calibration constant of the instrument. Ampling was continuous during measurement, the data shown in the following table cover a quarter of an hour period. The surface-protective effect of the additive is illustrated in figure 2.

Table I Without additive NOx HC CO2 O2 NOx corr. m % % m m 19 2,52 15, 4 67 79,663 18 2,5 15,4 67 79, 663 19 2,49 15,5 67 79,663 18 2,48 15,5 67 79, 663 19 2,5 15,5 67 79,663 18 2,51 15,4 67 79, 663 20 2,51 15,4 67 79,663 20 2,52 15,3 67 79,663 19 2,5 15,4 67 79,663 19 2,48 15,4 67 79,663 16 2,51 15, 4 67 79,663 17 2,51 15,4 67 79,663 17 2, 52 15,4 67 79,663 17 2,52 15,4 68 80,852 18 2, 5 15,4 68 80, 852 18 2,51 15, 4 68 80, 852 With additive, after 25 hours of additive feeding HC C02 02 NOx NOx corr. (ppm) (%) (%) (ppm) (ppm) 1 2, 38 15, 2 57 67, 773 1 2,37 15,2 57 67, 773 3 2,38 15,2 57 67, 773 2 2,37 15, 2 55 65,395 0 2,37 15,2 55 65, 395 3 2,37 15,2 54 64,206 3 2, 36 15,2 52 61,828 2 2,36 15,1 55 65,395 3 2,37 15,2 54 64,206 3 2,38 15,2 54 64,206 3 2,37 15,2 55 65,395 4 2,38 15,2 55 65,395 4 2,38 15,2 54 64,206 3 2, 38 15,2 55 65,395 4 2, 36 15, 1 54 64,206

Example 2 A DAF camion refuelled a diesel fuel consisting of 1 % by weight of sodium trihydrogen pyrophosphate, 3.5 % by weight of fatty acid polyglycerol ester (Emulsogen OG, Cariant), 4 % by volume of octylamin (Genamin 8 R 100 D, Cariant) 2% ethoxylated fatty acid ester (Genagen 0-100, Cariant) and the remainder diesel oil, with an average consumption of 43-45 I/100 km without additive, as it can be seen from the initial data in Table II. The additive was fed into the diesel fuel of the vehicle in a dilution ratio of 1: 1000. The earlier fuel consumption was reduced to 37-39 I/100 km. The change in fuel consumption is shown in Table I1.

Table II Change in fuel consumption plotted against the distance covered with the additive Fuel Covered Cumulated Average fuel intake (I) distance distance consumption (km) (km) I/100 km 405 761 761 44, 22 329 871 1632 43, 23 383 575 2207 43,97 222 832 3039 38, 6 328 840 3879 39,42 365 907 4786 40,24 345 921 5707 37,45 387 1027 6734 37,68 385 961 7695 40,06 408 1052 8747 38, 78 389 1018 9765 38, 21 434 1093 10858 39, 7 324 831 11689 38,9 358 931 12620 38,45 180 440 13060 40,9 342 797 13857 42,9 186 510 14367 36,47 280 725 15092 38,62 490 1307 16399 37,49 Example 3 A Volkswagen Transporter small bus with petrol engine refuelled a fuel consisting of 0.5 % by weight of potassium dihydrogen orthophosphate, 3. 5 % by

volume of fatty acid polyglycerol ester (Emulsogen PN Extra, Cariant), 2,4 % by volume of fatty acid diethanolamide (Hicor BAT, Cariant), 2% ethoxylated fatty acid ester (Emulsogen EL, Cariant) and the remainder desulphurized petrol, with an average consumption of 9.5-10. 5 I/100 km without additive. The additive was fed into the petrol fuel of the vehicle in a dilution ratio of 1: 1000. The earlier fuel consumption was reduced to 8.5-9. 0 U/100 km. The change in fuel consumption is shown in Table 111.

Table III Change in fuel consumption plotted against the distance covered with the additive Covered distance with Cumulated Average fuel the additive distance consumption (km) (km) 1/100 km 756 756 10, 2 713 1469 10, 4 746 2215 9, 7 705 2920 9, 1 765 3685 9 804 4489 8,7 778 5267 8, 5 Example 4 Into the petrol fuel of a motor vehicle type FSM 126AT we fed a fuel consisting of 0. 5% of sodium dihydrogen orthophosphate, 12% of ethoxylated fatty acid polyglycol ester (No. 5. 5EO, with C16 unsaturated fatty acid, lpamin SG P6, Egyesult Vegyimuvek Rt), 3% of fatty acid polyglycerol ester (EO 5.5 oleic acid derivative, Emulsogen OG, Cariant), 4% of aliphatic polyamine (Aicamide EB, Cariant) and the remainder desulphurized petrol, in a dilution ratio of 1: 1000. The measured values of CO emission plotted against the covered kilometres are shown in figure 2. Feeding was started at 95000 km.