CS272623B1 - Diesel oil with improved combustion properties - Google Patents

Abstract

This diesel fuel with improved combustion properties is prepared using a mixture of components A, B and C acquired by a combination of distillation and hydrodesulphurization, which form at least 70 % by weight of the ready fuel. Component A is a hydrocarbon distillate with a boiling point between 140 to 320 degrees C and sulphur content up to 0.45 % by weight, component B is a hydrocarbon fraction with a fractional range from 180 to 400 degrees C and sulphur content up to 0.2 % by weight, while component C is a petroleum distillate with fractional range of 181 to 420 degrees C and sulphur content up to 0.4 % by weight. The by-products are a hydrocarbon distillate with boiling point between 230 and 380 degrees C from hydrocracking, a refined product acquired by separation of n-alkanic hydrocarbons by adsorption on molecular sieves of the hydrocarbon fraction with distillation range from a range of temperatures of 140 to 320 degrees C and mixture of aromatic hydrocarbons with a boiling point over 140 degrees C.

Description

The present invention relates to a new type of fuel for compression ignition engines with improved combustion properties and to a process for its production from petroleum feedstock by combining oil distillation and hydrogenation desulfurization.

The constant trend of increasing the proportion of diesel (diesel) engines to drive both freight and passenger cars is conditional on an increase in diesel fuel production. Based on current forecasts, the production of diesel fuels will continue to increase, which in addition to technological problems also brings environmental problems. Increasing amounts of toxic exhaust gases from compression ignition engines, including in particular sulfur oxides, nitrogen oxides, carbon monoxide and carbon black, cause significant damage to vegetation and in particular to forests. The very negative effect of sulfur and nitrogen oxides, which cause so-called. acid rain caused a gradual limitation of the sulfur content of diesel fuels, which stabilized in the European fuels at a level of 0.1 to 0.5% by weight. At the same time, environmental regulations are being prepared limiting the content of nitrogen oxides (ΝΟ _χ ) and carbon black, which as carriers of carcinogenic substances are considered to be one of the most toxic components of diesel exhaust. In this way, trends in increasing fuel consumption for diesel engines and ecological requirements come into conflict.

The increase in diesel fuel production is usually realized by using products from fission processes, mainly from catalytic cracking. However, diesel fuels containing these products are characterized by deteriorated stability and a significantly reduced cetane number, which has to be solved by the addition of cetane number enhancers, usually based on alkyl nitrates, such as e.g. amyl nitrate, butyl nitrate, cyclohexyl nitrate and the like. Such fuels are also uncleanly burnt and cause deposits on the injection nozzles and in the combustion chamber of the engine. Remedying these drawbacks needs to be addressed by the addition of detergent additives.

It has been shown that, without major investment costs, diesel oil fuel extracts can be increased so that they have an extended distillation curve towards higher and / or lower temperatures compared to current fuels. Reducing resp. while increasing and decreasing the fraction range of diesel fuels simultaneously, respectively. they maintain combustion properties, but the fuel has a lower cetane number, which has to be solved by adding the listed additives. The production of such fuels, however, has a very negative effect in reducing the yield of fuels for jet engines and also of gasoline, which is economically very disadvantageous and practically impermissible in terms of meeting the needs of the national economy.

In the production of fuels with a higher fractional range, ie. the compounding of heavier hydrocarbon distillates into diesel fuels deteriorates their combustion, resulting in increased fuel consumption, increased carbon monoxide and soot content in the exhaust gas, and increased deposits in the combustion chamber of the engine, particularly on the engine pistons.

The present invention relates to a new type of diesel fuel and a process for producing it, which makes it possible to simultaneously increase the production of diesel fuel from petroleum and also that the fuel according to the invention is characterized by improved combustion properties. as a result, the diesel engine exhaust contains less harmful substances. This surprising conclusion is achieved by optimizing the component composition, the fractional range of the components as well as the manufacturing process of the fuel according to the invention, which ensures that although the new type of diesel fuel has a fractionally heavier composition, its combustion characteristics outperform the combustion properties of hitherto known and produced fuels even without the use of enhancing additives. The markedly improved combustion properties of the diesel fuel according to the invention are also manifested in the fact that there is no formation of deposits in the combustion chamber of the engine during combustion and the pistons of the engine are almost perfectly clean. As a result of the optimum composition of the fuel components for compression ignition engines and the method of production thereof according to the present invention, it is incinerated in the combustion process. The diesel engine is a synergistic interaction of individual groups

CS 272623 B1 of hydrocarbons, which affects the speed and perfection of fuel combustion, which is directly reflected in the previously described improved cleanliness of the engine combustion chamber and in the more favorable composition of the exhaust gas of the diesel engine.

The main fuel component for diesel engines with improved combustion properties according to the invention constitutes at least 70% by weight. the finished fuel is a mixture of components A,

B and C, wherein component A is a hydrocarbon distillate and / or hydrodesulfurized petroleum distillate having a boiling point of 140 to 320 ° C and a sulfur content of 0.1% to 0.45% by weight, component B is petroleum and / or hydrogenated Sulfurized petroleum fraction having a fraction of 180 to 400 ° C and a sulfur content of up to 0,2% by weight and component C is a hydrocarbon distillate and / or hydrodesulfurized petroleum distillate having a fractional range from 181 to 420 ° C and a sulfur content of from 0.03% to 0.4% by weight, wherein the content of the individual components in their mixture is from 5% to 65% wt. for component A, from 3% to 85% by weight of the composition; for component B and from 2% to 90% by weight of the composition; for component C, wherein the sulfur content of the resulting hot is from 0.05% to 1.15% by weight, the distilled amount to 360 ° C being at least 85% by volume. and its cetane number is above 42 units. The by-products are mixtures of aromatic hydrocarbons boiling above 140 ° C, the raffinate obtained after separation of the n-alkane hydrocarbons by adsorption on molecular sieves from a hydrocarbon fraction with a distillation range of 140 ° C to 320 ° C, a hydrocarbon distillate having a fractionation 230 to 380 ° C from a hydroprocessing of an oil fraction with a distillation range of 250 to 575 ° C and additives or additives improving oxidation stability and / or freezing point and a fuel filtering limit temperature at temperatures below 5 ° C.

The process for producing fuel according to the invention comprises a combination of distillation and hydrogen desulfurization processes and consists of atmospheric distillation of one part of the oil, in addition to fractions up to 170 to 195 ° C, of components A A and B ^, 170 to 195 ° C by the components of N and C wherein _{the FS} salsa step of the fuel is hydrogen treated component, and B ^ C ^ · saith the for the components B and C, and component a is made up hydrogenačně- desulfurizing component and / or distillate of N, wherein the resulting fuel is prepared by sequential or simultaneous homogenization of components A, B and C and, if appropriate, co-components.

The following examples illustrate the advantages, properties and process of producing fuel for diesel engines according to the invention, but without limiting the scope of the invention in any way.

Example 1

A portion of the crude oil was distilled off by atmospheric distillation to hydrocarbon fractions A.l and B.l, the hydrocarbon fraction A.l having a boiling point of from 162 to 272 ° C and the hydrocarbon fraction B.l having a fractional composition from 187 to 369 ° C (Variant A). The other part of the oil was also distilled off by atmospheric distillation into 2 hydrocarbon fractions A.l and C.l so that the hydrocarbon fraction C.l had a boiling point of 197 ° C to 394 ° C (Variant B). The yields of the hydrocarbon fractions obtained according to variants A and B are shown in Table 1. The hydrocarbon fractions obtained by atmospheric distillation of petroleum oil were wholly or partially hydrodesulfurized at a temperature of 340 to 380 ° C and a pressure of 4.1 atm on hydrogenation-refining catalysts. -molybdenum, respectively. nickel-molybdenum supported on aluminum. The hydrocarbon fractions A, B and C were obtained after hydrogenation desulfurization. In Table 2, mainly the qualitative indicators of the hydrocarbon fractions obtained according to the invention are summarized.

NM.l, resp. NM.2 according to the invention was prepared by compounding the hydrocarbon fractions A to C. The composition and properties of NM.la NM.2 diesel fuels are given in Table 3. It is clear from the above data that the qualitative indicators of diesel fuels according to the invention meet the typical national and international diesel fuel quality standards in Europe.

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The performance properties of the model diesel engine blends of the invention (NM.1 and NM.2) were monitored by engine tests on a Zetor supercharged Z8404 engine. The on-site engine tests were conducted under the conditions of external turnaround characteristics. The NM-22B diesel fuel produced according to PND 82-005-87, the quality of which is given in Table 3, was used as a comparative fuel. During the tests, the effect of fuel on engine performance and exhaust gas composition was monitored. Based on the results obtained in Table 4, the combustion properties of the diesel fuels of the present invention are significantly superior to the NM-22B diesel, thus showing the novelty of the present invention.

Example 2

The diesel fuels NM.3 to NM.6 were prepared by mixing the ingredients obtained with the procedure given in Example 1 (Tables 1 and 2). Composition and properties of diesel fuels NM.3. to NM.6 are shown in Table 5. The site engine tests investigated the effect of the diesel fuel fractional composition on the Zetor supercharged smoke, measured with a Hartridge-MK-3 dymometer. Current NM-22B diesel fuel for winter was used as a comparative fuel, the properties of which are described in Table 3 (Example 1).

Experimentally, the smoke values measured under the external engine speed conditions are shown in Table 6. The results show that the fuels of the present invention are characterized by improved combustion properties, and thus their optimum composition positively positively reduces the smoke of the diesel engine.

Example 3

The distillation of crude oil by atmospheric distillation into the hydrocarbon fractions A1, B1 and Cl according to variants A and B according to the invention (Example 1) yielded an atmospheric residue from which a hydrocarbon fraction D1 having a boiling point of 530 ° C and a density of 927 kg was prepared by vacuum distillation. m ^-3 at 20 ° C. In a salt step, the hydrocarbon fraction 0.1 having a kinematic viscosity of 12 mm ² · s ^-1 at 100 ° C was subjected to hydrogenation cracking at 390 ° C and 14.7 MPa using a molecular sieve catalyst to which the transition metals were deposited. Component D for diesel was obtained, the quality of which is given in Table 7.

The resulting diesel sample (NM.7) contained 75 wt. mixtures of A.l components,

B and C obtained with the procedure described in Example 1. The ratio by weight of components A.1: B: C to 1: 2.4: 1.1 was relative to each other. The minor components of NM.7 fuel (25 wt.% Of the total fuel weight) were component D prepared as described above, a mixture of aromatic hydrocarbons boiling above 150 ° C raffinate obtained after separation of the n-alkane hydrocarbons by adsorption on molecular sieves from the hydrocarbon fraction with distillation in the range from 150 ° C to 320 ° C. The qualitative parameters of this raffinate and the NM.7 finished fuel are given in Table 7.

With this diesel fuel, a long-term 200-hour test was performed on the Tatra 7929 engine for variable operating conditions, including idling, 1240, 1720, and 2200 revolutions per minute at varying engine load. Upon completion of the test and dismantling of the engine, it was shown that no deposits were formed in the engine combustion chamber, piston rings, injection pump and injection nozzle orifices during fuel testing, indicating the excellent combustion properties of the fuel of the invention.

Example 4

The non-turbocharged Tatra 7928 engine was monitored for NM.8 diesel according to the invention (30 wt% hydrocarbon fraction A, 14 wt% hydrocarbon fraction B and 56 wt% hydrocarbon fraction C1) with a distillation range from 181 ° C to 383 ° C

CS 272623 Bl * 4 on engine parameters within the load characteristic range at 1000, 1400,

2200 min and external speed characteristic with constant adjustment of the injection pump control rod. NM-22B diesel of current production was used as a comparative fuel, the qualities of which are given in Table 3 (Example 1). In Table 8 the power and specific fuel consumption values obtained at the measured points of the external speed characteristic are given. It has been confirmed by engine tests that NM.8 diesel according to the invention does not adversely affect engine parameters. Conversely, the diesel fuel tests according to the invention have shown that even the non-turbocharged engine has increased engine power, while the specific fuel consumption is at the level of the comparative diesel fuel, suggesting improved combustion properties of the diesel fuel of the invention.

Table 1

Extracts of hydrocarbon fractions obtained under variants A and B

Hydrocarbon fractions Extracts Variant A (% by weight) Variant B A.L. 11.24 11.43 B. L. 18.73 - No. I - 26.35

Table 2

Qualitative indicators of the hydrocarbon fractions obtained according to the invention

Qualitative hydrocarbon fractions

indicators A.L. B. L. No. I Density at 20 ° C, ^kg.m-a 809 847 858 Sulfur content ⁺ ,% wt. 0.29 / 0.05 / 0.71 / 0.08 / 0.74 / 0.1 / Freezing point, ° C -48 -8 0 Filterability, ° C -47 -2 +7 Dest.kravka up to 360 ° C predest. % Obj. 100 98 86

Note: + the sulfur content of the relevant hydrocarbon fraction after hydrogenation. desulphurisation is indicated in brackets

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Table 3

Qualitatively indicators of diesel fuels prepared according to the invention and composition of hydrocarbon fractions used in their compounding, resp. quality of NM-22B diesel fuel (outside the invention)

Motor according to the invention diesel outside the invention NM-22B NM.l NM.2 Composition (Wt hydrocarbon fraction A.L. • 14.63 20- 00 hydrocarbon fraction B. L. 5.42 1.92 hydrocarbon fraction B 55,56 38.70 hydrocarbon fraction C 24.39 39.38 Properties of NM Density at 20 ° C, kg 846 844 ' 837 2 - Kinematic viscosity, mm 1 - at 20 ° C 5.85 6.40 4.31 Flash point, ° C 68 66 58 Pour point, ° C -26 -24 -33 Filterability, ° C -10 - 7 -17 Depressant amount ⁺ T ppm 150 150 150 Sulfur content,% by weight 0.15 0.14 0.12 Distillation curve 10% vol. to ° C 226 219 217 50% vol. to C 286 283 270 90% vol. to C 349 348 337 end of distillation 385 389 362

Note: Depressant based on polyethylene / vinyl acetate copolymer containing 38% by weight of vinyl acetate was used to achieve low temperature properties

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Table 4

Comparison of performance properties of NM.la NM.2 diesel fuel prepared according to the invention and current NM-22B diesel fuel (except _{in the} invention) at nominal speed (2200 min ^-1 ) for turbocharged Zetor Z8404 engine

Engine parameters M 0 acc. To NM.1 of the invention NM.2 diesel outside the invention NM-22B Engine power, kW 77.5 77.1 76.4 Reduced torque, N.ro 342.7 340.9 336.3 Composition of exhaust gas: - CO content, ppm 139 143 180 - content ΝΟ _χ , ppm 1180 1230 1350 CH content, ppm 186 198 226 - CO ₂ content, wt. 3.7 4.2 5.4 Note: CO content NO content Cir content CO ₂ carbon monoxide content nitrogen oxides content unburnt hydrocarbon content carbon dioxide content Table 5 Composition and properties of the invention motorových náft NM.3 to NM.1 5 prepared M o NM.3 NM.4 naft NM.5 and NM * 6 Mass composition hydrocarbon fraction A 10.0 10.0 hydrocarbon fraction A.L. 10.0 10.0 15.0 - hydrocarbon fraction B 30.0 .15 / 0 - - hydrocarbon fraction B. L. - 5.0 - - hydrocarbon fraction C 50.0 70.0 85.0 84.4 hydrocarbon fraction C. L - - - 5.6 Properties of fuels Density at 20 ° C, kg.m ^-3 844 851 850 853

Kinematic viscosity, mm

- at 20 ° C 6.2 7.6 8.3 8.9 Pour point ⁺ , ° C -29 -21 -17 -15 Filterability, C -10 - 8 - 2 0 Sulfur content,% by weight 0.14 0.15 0.13 0.16 Distillation test ZD 182 186 187 191 10% vol. 220 227 230 238 50% vol. 281 295 297 302 90% vol. 355 362 365 368 KD 382 385 389 394

Note: ⁺ containing 300 ppm depressant additive

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Table 6

Comparison of the Zetor turbocharged smoke in the external engine speed conditions when the diesel fuel according to the invention (NM.3 to NM.6) is heated with the present NM-22B diesel fuel (outside the invention)

Engine speed (min) D y NM.3 m e n i e NM.4 engine (HSU ⁺ ) NM.5 NM.6 NM-22B 2200 19 18 14 12 21 1960 21 20 17 17 24 1720 35 33 33 31 37 1600 54 53 51 50 56 1480 75 74 73 71 76 1240 82 79 76 75 83 1000 88 88 ⁸⁶ 84 ⁹¹

* USU (Hardtridge Smoke Unit)

Table 7

Qualitative indicators of NM.7 diesel fuel according to the invention and the components used in its compounding

Qualitative components Diesel fuel indicators D raffinate NM.7

Density at 20 ° C, kg.m ^- 828 828 838 2 —1 Kinematic viscosity, mm.s - at 20 ° C 8.6 2.3 6 Sulfur content,% by weight 0.0008 0,002 0 Dest.skúška ZD 282 198 184 10% vol. . 290 205 223 50% vol. 320 219 291 KD 368 276 379 Dest. up to 360 ° C% vol. 93 100 94

Table 8

Comparison of utility properties of NM.8 diesel according to the invention and the current production of NM-225 (outside the invention)

Engine speed engine diesel fuel min ^-1 NM.8 NM-22B Engine power, kw 2200 204.0 200.5 1400 144.1 141.0 1000 100.3 97.5 Specific fuel consumption, q / kWh 2200 247 248 1400 214 215 1000 213 213

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Claims (3)

OBJECT OF THE INVENTION Fuel for compression-ignition engines having improved combustion properties, characterized in that it is a major component of at least 70% by weight thereof. the finished fuel is a mixture of components A, B and C, where component A is a hydrocarbon distillate and / or hydrodesulfurized petroleum distillate boiling in the temperature range of 140 ° C to 320 ° C, component B is a petroleum fraction and / or hydrodesulfurized petroleum A fraction having a distillation range of 180 ° C to 400 ° C and component C is a hydrocarbon distillate and / or hydrodesulphurised petroleum distillate having a fractionation range of 181 ° C to 420 ° C, with the content of the individual components in their mixture % is from 5% to 65% by weight; for component A, from 3% to 85% by weight of the composition; for component B and from 2% to 90% by weight of the composition; for component C and the resulting fuel has a sulfur content of 0.05 to 1.15% by weight, a distilled amount of up to 360 ° C of at least 85% by volume, its cetane number is 42 units and may also contain by-products up to 30% % wt. 2. Diesel fuel according to claim 1, characterized in that the by-products thereof are mixtures of aromatic hydrocarbons boiling above 140 ° C; temperature from 140 ° C to 320 ° C, hydrocarbon distillate having a fractional range in the temperature range from 230 ° C to 380 ° C from the hydroprocessing of the petroleum fraction with a distillation range from 250 ° C to 575 ° C and additives or additives improving oxidation stability and / or freezing point and a fuel filterability limit temperature at temperatures below 5 ° C. 3. A process for producing diesel fuel according to items 1 and 2, by a combination of distillation and hydrogen desulfurization processes, characterized in that fractions A and B are prepared by distilling one part of the oil, while fractions A and C are obtained by distilling the other part; the next step in fuel production is the hydrogenation desulfurization of fractions A, B and C or portions thereof so that after mixing the desulfurized and non-desulfurized portions of components A, B and C and, if appropriate, the co-components, the resulting sulfur content in the hot is from 0.05% to 1.15% by weight.