THE METHOD FOR THE INTENSIFICATION OF GASEOUS FUEL COMBUSTION

TECHNICAL FIELD

The invention is applicable to the field of power generation, transportation of natural gas, metal manufacturing, recycling of organic industrial and consumer waste, i.e. may be utilized in installations that operate on hydrocarbon gaseous fuel.

BACKGROUND ART

A known method to intensify gaseous fuel combustion is using burners that premix air and fuel before burning (See. V. A. Speisher, Gas Burning at Power Stations and in Industry. Moscow. 1967 [B. A. Cπeftmep C>KHraHne ra3a Ha 3.πeκτpocτaHii,HflX H B πpoMbiuiJieHHOCTM. - M.: 3Heprn5i. 1967 - 252 c.]). The premix burners mix fuel with air in special devices called mixers. Then the mixture is inflamed as it discharges from the burner. The flame is stabilized with the help of tunnels, diaphragms, bodies of non-streamlined shape or other devices. Premix burners used to mix gaseous fuel with air have high thermal intensity in the burning area.

Shortcomings - Using only thermal activation of burning. No ion or radical fusion before combustion. This increases consumption of fuel and amount of incomplete combustion products.

Another known method to intensify gaseous fuel combustion uses ozone (See G. S. Stoliarenko et al. The Method of Fuel Combustion [a.c. N.-1453120 CCCP MKH ⁴ F 23 D 21/00; F 23 C 1 1/00. Cπocoδ oKuraHna ToruiHBa ( V. C. dwrnpeHKo H up.)]). With this method, some air is fed into the ozonizer which produces ozone in the proportion of 1 /500 - 1 /250 to the fuel. Then the mixture of ozone and air is conditioned with a flow of nonorganic alkaline absorbent, with approximately 10-1 IpH solution, in order to obtain oxygen-containing radicals from ozone. Air input is

maintained at the level where the coefficient of air excessiveness is 1.15 - 1.2. The vapor-air mixture of ozone and radicals, as an oxidizing agent, is delivered into the combustion area.

Shortcomings - A multi-staged technology is applied to obtain oxygenated radicals preceded by the stages of solution oxygenation. Oxygenated solutions are treated with the alkaline solution. Difficult to maintain an optimal pH value (pH value falling below 10 results in ozone slipping into the combustion area without producing radicals and creating undesired nitrogen oxides; pH value rising above 1 1 destroys ozone and assimilates radicals at great speed).

Another known method to intensify gaseous fuel combustion uses a powerful electromagnetic field (See Patent No. 2079786, MKI ⁶ F 23 D 14/24 - The Method for the Intensification of the Flame Jet Burning in the Boiler Burner by V. D. Dudyshev [riaτeHτ N° 2079786 Pocia, MKM ⁶ F 23 D 14/24 Cπocoβ HHTeHCHφHKauηH ropeHiω φaκejia ruiaMeHH B τoπκe κoτejibHθH ycτaH0BKH/ Ns 95109989/06 3aaBJi. 14.06.95 oπyδji. 20.05.97 βioji. Ne 14]). The gist of this method is that a powerful electromagnetic field is created by a controlled high voltage converter (by voltage and frequency), where high voltage potentials are transmitted through an injector insulated from the burner and the earth to the heating surfaces which are also electrically insulated from the combustion chamber. The electrically polarized flame jet generates additional ionization; the ions and the fuel and oxidizer radicals interact better and are discharged with the ionized air into the combustion area. ^u Fresh" electrons are injected into the flame jet by needles located on the surface of the heat receiving surface, therefore increasing the number of combustion initiation centers.

Shortcomings - Intensive power consumption involved in the generation of the electromagnetic field as the effect takes place due to higher voltage and current load. High temperatures in the combustion area have a significant impact on the stability of the electromagnetic field, which may result in an arc discharge and decrease the process efficiency. Creating an electromagnetic field requires electromagnetic discharge stabilization and high regulation precision.

The following method is the closest to the proposed one from the technical perspective. This is the method for the intensification of gaseous fuel combustion with the help of a device that prepares the oxidizer for fuel combustion (See Patent No. 52845 Ukraine. [riaτ. YKpaiHH N° 52845, MKH ⁶ F 23 C 1 1/00, oπyβji. 15.10.2003, 6κ)Ji. JMo 1 , 2003 p.]) by generating an electric discharge on the electrodes, which produces a high voltage electric field that improves the combustion process. The constant electric voltage of 20-25 kilovolt is provided. The electric field produces active particles out of the atmospheric oxygen, which are evenly distributed across the flow of the oxidizer.

Shortcomings - High direct current voltage up to 25 kilovolt is required (increased energy consumption is required to generate ions and ion radicals from oxygen and water vapor available in the atmospheric air). This method increases only the oxidizing capacity of the blow but it does not decrease the activation energy necessary for the endothermic process of decomposition of hydrocarbons in gaseous fuel, which results in only a limited saving of gaseous fue) (not more than 2-3%). The environmental reduction of toxicity of combustion gases is low either - 20-30%.

DISCLOSURE OF INVENTION

The goal of this invention is to reduce the activation energy for the endothermic process of decomposition of hydrocarbons in gaseous fuel due to pre-generation of hydrocarbon radicals, oxygen-containing radicals, hydrogen atoms, ions, and ion radicals in the gaseous fuel flow immediately before the combustion of the fuel-air mixture as well as during pre-flame preparation of the fuel-air mixture for the combustion.

The goal is achieved by providing - within the known method for the intensification of gaseous fuel combustion - an electric discharge to electrodes, which generates high voltage electric field that improves the combustion process. According to the invention, the gaseous fuel or fuel-air mixture, when injected, is treated with an

electric alternating high voltage Townsend (silent) discharge field and further undergoes catalytic treatment, which increases the content of hydrocarbon radicals and hydrogen atoms during combustion.

Oxygen-containing additives are added before the treatment of the gaseous fuel and/or fuel-air mixture to increase the content of oxygen-containing radicals during combustion.

Furthermore, a special type of electric discharge - Townsend (silent) discharge - is provided to the electrodes which are coated with dielectric and have catalysts superimposed on them.

Also, the applied Townsend (silent) discharge has the alternating potential while the voltage of 2 to 20 kilovolt is maintained to generate hydrocarbon radicals with the electric alternating high voltage field.

Furthermore, hydrocarbon radicals are generated by the gas discharge of increased frequency and alternating potential.

The comparative analysis of the proposed method and the prototype allows the conclusion that the proposed technical solution has the following features different from the prototype: the gaseous fuel or fuel-air mixture is introduced into the electric discharge; oxygen-containing additives are used; discharge voltage is reduced; electron-catalytic process is used to improve the fuel-air mixture during generation of hydrocarbon and hydrogen radicals, ions, hydrocarbon ion radicals, oxygen-containing radicals and hydrogen atoms. These features optimize the pre-flame preparation of the fuel-air mixture for the combustion and save power as the power consumption does not exceed 2.5 - 3.5 % of the energy effect obtained by using the proposed method. They also reduce the thermal component of the activation energy and therefore allow decreasing the consumption of fuel needed to maintain the combustion reaction and saving gaseous fuel by 1 1.8% or more, which by far exceeds the prototype.

The following describes the method of combustion intensification.

The method essentially consists of the physical, electric-power and thermochemical stages. Gaseous fuel and air are dosed, jetted and mixed into a gaseous fuel-air mixture which is supplied for combustion. In the prototype that uses the high voltage electric field, the combustion intensification is implemented at the stage of air injection. In the proposed method, the combustion intensification is implemented at the stage of fuel injection and preparation of the fuel-air mixture, i.e. while the fuel-air mixture is prepared for combustion.

BRIEF DESCRIPTION OF DRAWINGS

The proposed technical solution is represented by the drawing: see Fig. - Installation Diagram.

The process flow diagram in Fig. includes: 1 - gaseous fuel container; 2 - radicals. ions and ion-radicals generator unit; 3 - power supply for the ion-radicals generator; 4 - oxygen-containing compounds dosing unit; 5 - air blower (blast); 6 - flow regulators; 7 - burner (torch); 8 - electronic catalysis area; 9 - water heating area.

THE BEST MODE FOR CARRYING OUT THE INVENTION

The operating principle of the proposed method for the intensification of gaseous fuel combustion is demonstrated by examples of intensification of gaseous fuel combustion using various factors that together compose the proposed method of fuel gas combustion.

Gaseous hydrocarbons travel from the container ( 1 ) to the generator (2) where they go through the electric discharge area. Alternating voltage of 2 to 20 kilovolt is supplied to the generator (2) from the power supply (3) in order to generate the Townsend (silent) discharge. The air is supplied through the air blower (5) into the generator unit (2) and to the burner (7). Flow distribution and dosed mixing is

performed by the regulators (6). The gaseous fuel flow travels fully or partially through the dosing unit (4) for saturation with oxygen-containing compounds. The gas flow is directed for combustion to the burner (7) collocated with the electronic catalysis area (8). After the fixed combustion mode is set, the specific consumption of fuel for water heating is measured in each experiment. The comparative fuel consumption was measured with the same volume of water and same heating temperature difference depending on the heating time.

Tables 1 through 4 represent the experiment data regarding the intensification of gaseous fuel combustion by using various factors which were applied to develop the proposed method of fuel gas combustion.

Table 1 - Electron catalysis using methane without adding oxygen-containing compounds

Table 2 - Electron catalysis using methane with added oxygen-containing compounds (water or penozone [hydrogen peroxide solution])

Table 3 - Electron catalysis using propane-butane without adding oxygen- containing compounds

Table 4 - Electron catalysis using propane-butane with added oxygen-containing compounds (water or penozone/hydrogen peroxide solution)

As shown in Tables 1 to 4, using catalyst in pre-flame preparation of gaseous fuel or fuel-air mixture saves 1 1.8% of fuel, where methane is used as fuel. Using oxygen-containing additives before putting the fuel into the electric discharge (silent discharge) saves 13.5% of fuel. When propane-butane is used as fuel, fuel saving is 10% and 15.4% respectively.

Using gas discharge with high frequency voltage supplied to electrodes saved 15.2-19.6% of fuel. Therefore, the proposed method for the intensification of gaseous hydrocarbon combustion allows saving fuel due to generation of radicals, ions and ion- radicals in the fuel preparation area.

The proposed technical solution allows implementing the technology that intensifies gaseous fuel combustion in existing boilers of any power capacity. This technical solution does not involve any modification or adjustment of boiler furnaces. Modifications need to be made in the burner design. The electric equipment required for the electric silent or gas discharge is standard. Catalysts applied on electrodes and/or on dielectrics of high and low voltage electrodes are commonly available.

INDUSTRIAL APPLICABILITY

The experimental model in the form of a test bench installation was made and tested by the applicants.