CZ32703U1 - A device for reducing nitrogen oxide emissions from internal combustion engines - Google Patents

Description

Technical field

The technical solution relates to a device for reducing nitrogen oxides emissions from internal combustion engines of lean gas fired internal combustion engines.

BACKGROUND OF THE INVENTION

Increasing the power and efficiency of internal combustion engines is accompanied by an increase in nitrogen oxide emissions. Nitrogen oxides are formed during the combustion of the fuel in the combustion chamber of the internal combustion engine by oxidizing nitrogen from the combustion air. As for the formation of nitrogen oxides during combustion, the rule is that as the temperatures in the combustion chamber increase during combustion, the production of nitrogen oxides increases. Reduction of nitrogen oxide emissions in internal combustion engines can be achieved by two basic groups of processes and their combinations.

A first group of methods are measures directly affecting the result of the combustion process in the cylinder of an internal combustion engine. These measures include changing the ignition angle, changing the fuel to combustion air ratio, changing the engine compression ratio, using controlled exhaust gas recirculation, reducing the boost pressure in the internal combustion engine intake, reducing the temperature of the mixture using the charge air / mixture intercooler, and injecting water into the intake or directly into the combustion chamber.

By reducing the ignition angle, the temperatures during combustion and the nitrogen oxide emissions decrease. The disadvantage of this solution is that by reducing the ignition timing the exhaust gas temperatures increase and the overall engine efficiency may decrease. In addition, engines with atmospheric charge also reduce engine power.

For different values of the ratio of fuel and combustion air we distinguish rich mixtures - the amount of air is less than the theoretical air requirement, stoichiometric - the amount of air corresponds to the theoretical air demand and poor - the amount of air is greater than the theoretical air demand. In the area of lean combustion with a decrease in the proportion of fuel to the proportion of combustion air, the so-called mixture depletion, there is a decrease in temperatures during combustion and thus a decrease in nitrogen oxide emissions. The disadvantage of this solution is that with the depletion of the mixture, engine power, overall engine efficiency and engine run uniformity, and engine exhaust gas temperatures increase.

By decreasing the compression ratio of the engine, the temperatures during combustion are reduced and thus the emissions of nitrogen oxides decrease. The disadvantage of this solution is that by decreasing the compression ratio of the engine, the power and overall efficiency of the engine are reduced.

In controlled exhaust gas recirculation, the intake mixture is mixed in some proportion with a portion of the flue gas. This mixing of the mixture and the flue gas again causes a decrease in the temperatures during combustion and thus a decrease in the nitrogen oxide emissions. The disadvantage of this solution is its complexity and price. If the engine is not optimized, the increase in the proportion of combustion products at the expense of the proportion of the mixture leads to a decrease in engine power, overall engine efficiency and engine run uniformity, and an increase in engine exhaust gas temperatures.

By lowering the boost pressure in the intake system of the internal combustion engine, temperatures during combustion are reduced and thus nitrogen oxide emissions are reduced. The disadvantage of this solution is that decreasing the boost pressure results in a decrease in engine power.

- 1 GB 32703 U1

Lowering the temperature of the mixture with the charge air / mixture intercooler causes an overall decrease in the course of temperatures to lower values, i.e. temperatures during combustion and thus a decrease in nitrogen oxide emissions. The disadvantage of this solution is its complexity and price.

The injection of water into the intake manifold or directly into the combustion chamber will cause, with regard to the heat of heat to change the state of the water into water vapor, a decrease in temperatures and therefore temperatures during combustion and thus a decrease in nitrogen oxide emissions. The disadvantage of this solution is the high cost, manufacturing demands, complexity and higher engine failure rate.

The second group of processes is the post-treatment of the already produced flue gases with the aid of catalysts.

When operating the engine on a stoichiometric mixture, an oxidation-reduction catalyst is used. This catalyst reduces the emission of nitrogen oxides by means of the catalyst reducing portion and the emission of carbon monoxide and unburnt hydrocarbons by the oxidizing portion of the catalyst. For this reason, this catalyst is also sometimes called a three-way - it destroys three groups of pollutants. In lean engine operation, a catalytic reduction catalyst is used to reduce nitrogen oxides. The disadvantages of these solutions are high cost, very high complexity, limited catalyst life and higher engine failure.

By combining the individual measures, it is possible to eliminate a decrease in engine power and efficiency with a decrease in the production of nitrogen oxides. However, the combination of measures increases the cost of all measures, increases complexity, decreases reliability and increases engine failure.

The essence of the technical solution

The above drawbacks can be largely eliminated by the apparatus for reducing nitrogen oxide emissions from internal combustion engines according to the present invention. It is based on a device in which a mixture of methane, propane, hydrogen and nitrogen is added to the fuel anywhere in the engine fuel system and / or is added to the fuel / air mixture anywhere in the engine intake system and / or added directly to the internal combustion engine cylinder. final composition of fuel in the combustion chamber in the amount of methane 62 to 75% by volume, propane 8 to 12% by volume, hydrogen 8 to 12% by volume and nitrogen from 8 to 13% by volume and combustion air and / or ignition advance angle and / or engine compression ratio and / or engine boost pressure.

Said solution is one of the measures directly affecting the result of the combustion process in the cylinder of the internal combustion engine.

The essence of this technical solution is that the resulting composition of the fuel in the cylinder due to the determined content of methane, propane and hydrogen accelerates the course of combustion and heat generation by combustion in the cylinder of the internal combustion engine. This approximation of the working cycle to the theoretical one increases the efficiency and power of the engine. The determined nitrogen content of the resulting fuel composition in the cylinder will maintain the knock resistance of the fuel within the applicable limits.

This increased engine power is eliminated by depleting the fuel / air mixture and / or reducing the engine compression ratio and / or reducing the boost pressure in the engine intake system and / or, in the case of engines with atmospheric charge, by reducing the ignition timing angle nitrogen oxide emissions. In turbocharged engines, power growth is eliminated by increasing the ignition angle, as opposed to atmospheric charge engines. Reduction of nitrogen oxides due to depletion of fuel / air mixture and / or reduction of engine compression ratio and / or reduction of boost pressure in engine intake system and / or for atmospheric charge engines, reduction of ignition angle is greater than growth of nitrogen oxide emissions

-2GB 32703 U1 due to an increase in engine power caused by the addition of a mixture of methane, propane, hydrogen and nitrogen to the fuel and / or the fuel / air mixture.

Depleting the fuel / air mixture and / or reducing the engine compression ratio and / or reducing the boost pressure in the engine intake system and / or, in the case of engines with atmospheric charge, by reducing the ignition angle, engine performance, combustion temperatures and thus nitrogen oxide emissions . In turbocharged engines, the decrease in power as opposed to engines with atmospheric charge is due to an increase in the ignition angle. The decrease in nitrogen oxides is eliminated by adding a mixture of methane, propane, hydrogen and nitrogen to the fuel / fuel / air mixture. The essence of this technical solution is that the decrease in engine power caused by the depletion of the mixture and / or the reduction of the engine compression ratio and / or the reduction of the boost pressure in the engine intake system and / or in the case of atmospheric engines caused by the addition of a mixture of methane, propane, hydrogen and nitrogen to the fuel and / or the fuel / air mixture.

The reduction of nitrogen oxide emissions from internal combustion engines according to the present invention meets the requirement of maintaining engine power and efficiency and uniformity of engine operation. The increase in engine power according to this invention meets the requirement of maintaining a constant level of nitrogen oxide emissions from internal combustion engines. Increasing the efficiency of the engine according to the present invention meets the requirement of maintaining performance and a constant level of nitrogen oxide emissions from internal combustion engines.

The power and engine speed parameters are constant. A comparison of the two courses shows a faster burning and heat release by burning for the methane, propane, hydrogen and nitrogen mixture defined in this document compared to the reference fuel - methane.

It is a simple design solution that is simple and inexpensive to manufacture, does not increase engine complexity, does not reduce engine reliability, does not increase engine failure, and is low on operating costs.

Clarification of drawings

The technical solution will be explained in more detail on the examples of the technical implementation according to the attached drawings and on the graphic interpretation of the results from the simulation calculations.

Figure 1 shows a wiring diagram with a methane, propane, hydrogen, and nitrogen mixture to the engine fuel system. FIG. 2 shows another wiring diagram with methane, propane, hydrogen, and nitrogen inlet to the engine fuel system. FIG. 3 shows yet another circuit diagram with methane, propane, hydrogen and nitrogen gas supply to the engine fuel system. Fig. 4 shows a circuit diagram with the methane, propane, hydrogen and nitrogen mixture supplied directly to the cylinder of an internal combustion engine. FIG. 5 shows another wiring diagram with the methane, propane, hydrogen and nitrogen mixture supplied directly to the internal combustion engine cylinder. FIG. 6 is a circuit diagram with methane, propane, hydrogen, and nitrogen mixtures fed directly to the engine fuel system and fuel directly to the internal combustion engine cylinder.

Examples of technical solutions

FIG. 1 shows an example of an embodiment of a device for reducing nitrogen oxide emissions from internal combustion engines. An additional line 5 for supplying a mixture of methane, propane, hydrogen and nitrogen is connected to the gas supply line 3. The flow of the methane, propane, hydrogen and nitrogen mixture is controlled by means of the valve 6. The mixture of gaseous fuel and the mixture of methane, propane, hydrogen and nitrogen is led through the inlet pipe 7 to the intake system 1 of the internal combustion engine. hydrogen and nitrogen into the suction system 1

The U1 internal combustion engine is controlled by an additional valve 8. The intake system 1 is connected to the cylinder of the internal combustion engine 2.

Figures 2 and 3 show an example of an embodiment of a device for reducing nitrogen oxide emissions from internal combustion engines. A gas supply line 3 is connected to the intake system 1 of the internal combustion engine 2. The flow of gaseous fuel into the suction system 1 is regulated by a control valve 4. An additional line 5 is connected to the suction system 1 for supplying a mixture of methane, propane, hydrogen and nitrogen. The flow of the methane, propane, hydrogen and nitrogen mixture into the intake system 1 is controlled by the valve 6. The intake system 1 is connected to the cylinder of the internal combustion engine 2.

Fig. 4 shows an example of an embodiment of a device for reducing nitrogen oxide emissions from internal combustion engines. A gas supply line 3 is connected to the intake system 1 of the internal combustion engine 2. The flow of gaseous fuel into the intake system 1 is controlled by means of a control valve 4. An additional line 5 is connected to the cylinder of the internal combustion engine 2 for supplying a mixture of methane, propane, hydrogen and nitrogen. The flow of the methane, propane, hydrogen and nitrogen mixture into the cylinder of the internal combustion engine 2 is controlled by the valve 6. The suction system 1 is connected to the cylinder of the internal combustion engine 2.

Fig. 5 shows an example of an embodiment of a device for reducing nitrogen oxide emissions from internal combustion engines. The suction system 1 is connected to the cylinder of the internal combustion engine 2. The gas cylinder 3 is connected to the cylinder of the internal combustion engine 2. The flow of gaseous fuel into the cylinder of the internal combustion engine 2 is controlled by a control valve 4. An additional line 5 is connected to the cylinder of the internal combustion engine 2 for supplying a mixture of methane, propane, hydrogen and nitrogen. The flow of the methane, propane, hydrogen and nitrogen mixture into the cylinder of the internal combustion engine 2 is controlled by the valve 6.

FIG. 6 shows an exemplary embodiment of an apparatus for reducing nitrogen oxide emissions from internal combustion engines. An additional line 5 is connected to the intake system 1 of the internal combustion engine 2 for supplying a mixture of methane, propane, hydrogen and nitrogen. The flow of the methane, propane, hydrogen and nitrogen mixture into the intake system 1 is controlled by means of a valve 6. A gas supply line 3 is connected to the cylinder of the internal combustion engine 2. The flow of gaseous fuel into the cylinder of the internal combustion engine 2 is controlled by a control valve 4. The intake system 1 is connected to the cylinder of the internal combustion engine 2.

Industrial applicability

The apparatus for reducing nitrogen oxide emissions from internal combustion engines according to the present invention will find application especially in lean-gas fired gasoline internal combustion engines having a sufficient source of a mixture of methane, propane, hydrogen and nitrogen.

Claims (1)

An apparatus for reducing nitrogen oxide emissions from internal combustion engines, characterized in that the engine fuel system (2) and / or the engine intake system (2) and / or the cylinder of the internal combustion engine (2) is provided with methane feed; propane, hydrogen and nitrogen, connected to a control unit for adding a mixture of methane, propane, hydrogen and nitrogen to the fuel and / or a fuel / air mixture for the resulting fuel composition in the combustion space of 62 to 75% by volume, propane 8 to 12 vol.%, Hydrogen 8-12 vol.% And nitrogen 8-13 vol.