Method of staged combustion using preheated oxidant

FIELD: power engineering.

SUBSTANCE: method of fuel combustion when at least one fuel and at least two oxidants are injected: the first oxidant is injected at I1 distance equal to 20 cm at maximum and preferably 15 cm at maximum from point of fuel injection. The second oxidant is injected at I2 distance from point of fuel injection while I2 is greater than I1. Oxidants are injected in such amounts that sum of their amounts is equal to at least stoichiometric amount of oxidant required to provide combustion of injected fuel. The first oxidant is oxygen-enriched air at maximum temperature of 200 C, and the second oxidant is air preheated to temperature of at least 300 C. Air is enriched with oxygen so that oxygen concentration in enriched air is at least 30%. Oxygen-enriched air is obtained by mixing ambient air with oxygen from cryogenic source. Preheated air is heated by means of heat exchange using part of hot combustion products. At least two oxidants are injected at I1 distance equal to 20 cm at maximum and preferably 15 cm at maximum while one oxidant called primary is injected mixed with fuel or near fuel and another oxidant called secondary is injected at distance from fuel. Amount of oxidant injected by means of primary oxidant jet ranges from 2 to 50% of oxygen stoichiometric amount required to provide combustion of injected fuel. The secondary oxidant is separated into multiple jets of secondary oxidant. The second oxidant injected at distance I2 is separated into multiple jets of oxidant.

EFFECT: fuel combustion using oxygen as oxidant suitable for retrieving energy from furnace gases.

8 cl

 

The present invention relates to a method staged combustion using preheated oxidant.

In existing ways of burning usually extract the energy released using ovens to reduce fuel consumption. Heat, portable flue gases, can be retrieved through the use of waste heat boilers or regenerators. This energy recovery is, in particular, General methods of combustion, in which the oxidizing agent is air.

For combustion, in which the oxidant is oxygen, it is also desirable to extract the energy. However, the technology suitable for air, you cannot directly apply for oxygen. Indeed, the combustion gases produced by burning with oxygen, have a higher moisture content and can contain a significant amount of corrosion particles. Currently there are two technologies for pre-heating oxygen:

in US-A-5807418 described direct heat exchange with the combustion products and oxidant containing at least 50% oxygen,

according to US-A-6071116, the intermediate fluid and the first heat exchanger to extract energy from the exhaust gases before returning this energy to the oxygen through the second heat exchanger.

These technologies can cause opredellennie problems such as maintenance problems of heat exchangers and life, especially due to corrosion, lack of means to measure and control the hot oxygen (no controls, compatible with hot oxygen), and security issues associated with the use of the hot oxygen.

The basis for this invention is the task of creating a new method of combustion using oxygen as oxidant and suitable for extraction of energy from the flue gases.

Another objective of this invention is to provide a new method of combustion using oxygen as oxidant and suitable for extraction of energy from the flue gases without problems when pre-heating oxygen.

To solve these problems in accordance with the invention created a method of burning fuel, which is injected, at least one fuel and at least two oxidizer:

the first oxidant injected at a distance of I1equal to the maximum of 20 cm and preferably a maximum of 15 cm from the point of fuel injection,

the second oxidant injected at a distance of I2from the point of injection of fuel, and I2more I1while the oxidant injected in such molar amounts that their total molar number of the TV is equal to, at least the molar stoichiometric amount of oxidant required to ensure combustion of the injected fuel and the first oxidant is oxygen-enriched air having a temperature maximum of 200C, and the second oxidant is air, preheated to a temperature of at least 300C.

According to the invention, a method of burning is a way of staged combustion. This method of burning includes the introduction of oxidant required for combustion of the fuel, in the form of at least two separate streams that can be injected at various distances (I1and I2from the point of introduction of the fuel into the furnace. The first oxidant injected in such quantities that it causes incomplete combustion of fuel and gases formed due to the combustion of fuel and the first oxidant still contain at least part of the fuel. The second oxidant injected in such quantities, at which complete combustion of the fuel is still present in the gases produced by the combustion of fuel and the first oxidant. According to the invention, the oxidant injected in such quantities that their sum of amounts equal to at least the stoichiometric amount of oxidant required to ensure combustion of fuel to be injected. Stoichiometric amount means the AET number of molecules of oxygen, required for complete combustion of the injected fuel. Various oxidizing agents must submit at least all the oxygen required for complete combustion of the fuel.

According to one essential characteristic of the invention, the first oxidant injected at a distance of I1consists of oxygen-enriched air having a temperature maximum of 200C. "oxygen Enriched air" means the air is enriched with oxygen so that the oxygen concentration in the enriched air is at least 30%, and preferably at least 50%. Oxygen-enriched air is preferably get by mixing ambient air with oxygen from a cryogenic source. The oxidant injected at a distance of I1has a maximum temperature of 200C, which means that the oxidant is preheated, in particular, by using regenerators energy from the furnace in which combustion. According to another essential characteristic of the invention, the second oxidant injected at a distance of I2consists of air, preheated to a temperature of at least 300C. Pre-heating can be accomplished using any technology to extract heat from the hot products of combustion from the furnace. That is they way preheated air can be heated using a heat exchanger using part of the hot products of combustion in accordance with any known from the prior art technology.

In accordance with one embodiment of the method according to the invention, at least two oxidant injected at a distance of I1equal to a maximum of 15 cm, with one oxidizing agent, called primary, injected in a mixture with the fuel at or near a fuel, and the other oxidizer, called secondary, inject at a distance from the fuel. "Mixed" means that the primary oxidant and fuel are pre-mixed prior to introduction into the combustion zone. This preliminary mixing may be accomplished through the injection of primary oxidant and fuel into the cavity, with the cavity ends in the zone of combustion. "Near" means that the primary oxidant oxidant is introduced at the point closest to the point of introduction of fuel among all other oxidizing agents that can be injected in the process of combustion. The secondary oxidant is injected at a distance from the fuel, which is the distance IVtorichnyifrom the upper point of introduction of fuel at a distance of IPervichnydefined between the points of introduction of the primary oxidant and fuel. The primary oxidant and secondary the second oxidant may have different oxygen concentrations; preferably, the primary oxidant has a higher oxygen concentration than the secondary oxidant. The amount of oxidant injected by means of a jet of primary oxidant is preferably from 2 to 50% of the stoichiometric amount of oxygen necessary to ensure combustion of fuel to be injected. The amount of oxidant injected through jets of secondary oxidant, and a jet of oxidant injected at a distance of I2may be from 50 to 98% of the stoichiometric amount of oxygen necessary to ensure combustion of fuel to be injected. In this embodiment, the secondary oxidant can be divided into numerous jets of secondary oxidant, which can all be injected at the same distance IVtorichnyifrom jet fuel or at different distances IVtorichnyifrom jet fuel, while these distances remain shorter than 20 cm, preferably shorter than 15 cm

According to a particular variant embodiment of the invention, the oxidant injected at a distance of I2can be divided into many streams of oxidizer.

The method according to this invention can be applied to any type of combustion furnaces and, in particular, to heating furnaces, glass melting furnaces and furnaces for melting of ferrous or non-ferrous metals.

It was found that due to the implementation of the above method, although the method of air containing nitrogen, NOx emissions remain low and compatible with the standards of emission into the atmosphere. Therefore, the method according to this invention does not have the disadvantages associated with prior heating of oxygen, as well as disadvantages associated with the combustion with air. In addition, the use of enriched air limits the wear of the refractory materials.

1. A method of burning fuel, which inject at least one fuel and at least two oxidizer:
the first oxidant injected at a distance of I1equal to the maximum of 20 cm, preferably a maximum of 15 cm from the point of injection of fuel; a second oxidizer injected at a distance of I2from the point of injection of fuel, and I2more I1while the oxidant injected in such quantities that their sum of amounts equal to at least the stoichiometric amount of oxidant required to ensure combustion of fuel to be injected, wherein the first oxidant is oxygen-enriched air having a temperature maximum of 200C, and the second oxidant is air, preheated to a temperature of at least 300C.

2. The method according to claim 1, from which causesa fact, that air is enriched with oxygen so that the oxygen concentration in the enriched air is at least 30%.

3. The method according to any one of claims 1 or 2, characterized in that the oxygen-enriched air get by mixing ambient air with oxygen from a cryogenic source.

4. The method according to claim 1, characterized in that the preheated air is heated by heat exchange with part of the hot products of combustion.

5. The method according to claim 1, characterized in that at least two oxidant injected at a distance of I1equal to the maximum of 20 cm, preferably a maximum of 15 cm, with one oxidizing agent, called primary, injected in a mixture with the fuel at or near a fuel, and the other oxidizer, called secondary, inject at a distance from the fuel.

6. The method according to claim 1, characterized in that the amount of oxidant injected by means of a jet of primary oxidant is from 2 to 50% of the stoichiometric amount of oxygen necessary to ensure combustion of fuel to be injected.

7. The method according to claim 5 or 6, characterized in that the secondary oxidant is divided into numerous jets of secondary oxidant.

8. The method according to claim 1, characterized in that the second oxidant injected at a distance of I2share on jet set acyclical is.



 

Same patents:

FIELD: the invention refers to the technology of using a cumulative jet.

SUBSTANCE: the mode of formation of at least one cumulative jet includes feeding of at least one gas jet out of at least one nozzle with a converging/diverging configuration located in an injector having a face surface of the injector. At that the face surface of the injector has openings located along the circumference around at least one nozzle, moreover the indicated at least one gas jet has a supersonic speed when it is formed at the output from the face surface of the injector and remains supersonic on a distance coming to at least 20d, where d- the diameter of the output opening of the indicated at least one nozzle. Feeding of fuel from the first group of openings located along the circumference and feeding of an oxidizing agent from the second group of openings located along the circumference. Incineration of fuel and the oxidizing agent fed from the first and the second groups of openings located along the mentioned circumference for formation of a flame shell around at least one gas jet. A great number of gas jets are fed from the injector. The fuel and the oxidizing agents are fed from the first group of openings and from the second group of openings correspondingly alternate with each other on the circumference along which they are located. At least one gas jet, the fuel and the oxidizing agent are fed from the injector directly into the space for injection without passing the zone of recycling formed with the extender of the injector. At least one gas jet passes at a prescribed distance coming at least to 20d, where d- is the diameter of the output opening of the nozzle from which exits a gas jet keeping the diameter of the mentioned gas jet in essence constant.

EFFECT: the invention allows make an arrangement with the aid of which it is possible to form effective cumulative gas jets without need in an extender in the injector or in any other element for forming recycling zone for gases fed from the injector.

9 cl, 3 dwg

FIELD: power engineering.

SUBSTANCE: method comprises injecting at least one type of fuel and at least one oxidizer. The primary oxidizer is injected together with the fuel to generate first incomplete burning. The gases emitting from the first burning comprises at least a part of the fuel, whereas the secondary oxidizer is injected downstream of the site of the fuel injection at a distance larger than that between the fuel injection and primary oxidizer closest to the fuel injection so that to be burnt out together with the fuel part. The flow of the first oxidizer is branched into at lest two primary flows.

EFFECT: reduced emission of nitrogen oxides.

40 cl, 8 dwg

The invention relates to a method for partial oxidation of hydrocarbons and gaseous mixtures containing hydrogen and carbon monoxide

Gas burner // 2213300
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Hearth burner // 2211403
The invention relates to bottom (horizontal slot) single tube burners with forced air for combustion of gaseous fuel and can be used in heating sectional boilers, Asilah, etc

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Slit bottom burner // 2075693

FIELD: power engineering.

SUBSTANCE: method comprises injecting at least one type of fuel and at least one oxidizer. The primary oxidizer is injected together with the fuel to generate first incomplete burning. The gases emitting from the first burning comprises at least a part of the fuel, whereas the secondary oxidizer is injected downstream of the site of the fuel injection at a distance larger than that between the fuel injection and primary oxidizer closest to the fuel injection so that to be burnt out together with the fuel part. The flow of the first oxidizer is branched into at lest two primary flows.

EFFECT: reduced emission of nitrogen oxides.

40 cl, 8 dwg

FIELD: the invention refers to the technology of using a cumulative jet.

SUBSTANCE: the mode of formation of at least one cumulative jet includes feeding of at least one gas jet out of at least one nozzle with a converging/diverging configuration located in an injector having a face surface of the injector. At that the face surface of the injector has openings located along the circumference around at least one nozzle, moreover the indicated at least one gas jet has a supersonic speed when it is formed at the output from the face surface of the injector and remains supersonic on a distance coming to at least 20d, where d- the diameter of the output opening of the indicated at least one nozzle. Feeding of fuel from the first group of openings located along the circumference and feeding of an oxidizing agent from the second group of openings located along the circumference. Incineration of fuel and the oxidizing agent fed from the first and the second groups of openings located along the mentioned circumference for formation of a flame shell around at least one gas jet. A great number of gas jets are fed from the injector. The fuel and the oxidizing agents are fed from the first group of openings and from the second group of openings correspondingly alternate with each other on the circumference along which they are located. At least one gas jet, the fuel and the oxidizing agent are fed from the injector directly into the space for injection without passing the zone of recycling formed with the extender of the injector. At least one gas jet passes at a prescribed distance coming at least to 20d, where d- is the diameter of the output opening of the nozzle from which exits a gas jet keeping the diameter of the mentioned gas jet in essence constant.

EFFECT: the invention allows make an arrangement with the aid of which it is possible to form effective cumulative gas jets without need in an extender in the injector or in any other element for forming recycling zone for gases fed from the injector.

9 cl, 3 dwg

FIELD: power engineering.

SUBSTANCE: method of fuel combustion when at least one fuel and at least two oxidants are injected: the first oxidant is injected at I1 distance equal to 20 cm at maximum and preferably 15 cm at maximum from point of fuel injection. The second oxidant is injected at I2 distance from point of fuel injection while I2 is greater than I1. Oxidants are injected in such amounts that sum of their amounts is equal to at least stoichiometric amount of oxidant required to provide combustion of injected fuel. The first oxidant is oxygen-enriched air at maximum temperature of 200 C, and the second oxidant is air preheated to temperature of at least 300 C. Air is enriched with oxygen so that oxygen concentration in enriched air is at least 30%. Oxygen-enriched air is obtained by mixing ambient air with oxygen from cryogenic source. Preheated air is heated by means of heat exchange using part of hot combustion products. At least two oxidants are injected at I1 distance equal to 20 cm at maximum and preferably 15 cm at maximum while one oxidant called primary is injected mixed with fuel or near fuel and another oxidant called secondary is injected at distance from fuel. Amount of oxidant injected by means of primary oxidant jet ranges from 2 to 50% of oxygen stoichiometric amount required to provide combustion of injected fuel. The secondary oxidant is separated into multiple jets of secondary oxidant. The second oxidant injected at distance I2 is separated into multiple jets of oxidant.

EFFECT: fuel combustion using oxygen as oxidant suitable for retrieving energy from furnace gases.

8 cl

FIELD: heating.

SUBSTANCE: invention relates to power engineering. The proposed method of fuel firing with oxygen-containing gas wherein fuel jet is injected and, at least, two jets of oxygen containing gas that features high oxygen content. Note here that the 1st jet of aforesaid gas, called a primary jet, is injected to allow its contact with the fuel jet and to form the 1st incomplete firing. Note here that outlet gases, thereafter, contains, nevertheless, at least, one fraction of fuel. Note also that the 2nd aforesaid jet is injected at the distance from the fuel jet to allow firing together with the said 1st fuel fraction existing in outlet gases after 1st firing. The oxidiser primary jet is divided into two primary jets, that is, 1st primary jet, called the central primary oxidiser jet injected into fuel jet centre and 2nd primary jet called the embracing primary jet injected coaxially and around the fuel jet. The rate of the oxidiser central primary jet injection exceeds that of fuel jet injection. The fuel jet injection rate exceeds that of the 1st embracing oxidizer injection. The oxidiser 2nd jet injection rate exceeds that of the oxidiser embracing primary jet. The distance between the oxidiser central primary jet injection and its 2nd jet injection vs the rate of injection of the oxidiser 2nd jet varies between 10-3 and 10-2. The oxidiser 3rd jet is injected at the point located between the point of injecting the oxidiser central primary jet and that of injecting 2nd oxidising jet. The rate of injecting oxidiser 2nd jet exceeds that injecting oxidiser 3rd jet. The distance between the point of injecting oxidiser 2nd jet and that of injecting oxidiser central primary jet vs the distance between the point of injecting oxidiser 3rd jet and that of injecting oxidiser primary jet varies from 2 to 10. Two primary oxidiser jets feature identical oxygen concentration. The oxidizer central primary jet oxygen concentration exceeds that of oxidiser embracing primary jet.

EFFECT: higher furnace reliability.

10 cl, 1 dwg

FIELD: heating.

SUBSTANCE: invention relates to powder engineering. The method of fuel firing with oxygen-containing gas wherein fuel jet is injected and, at least, two jets of oxygen containing gas that features high oxygen content. Note here that the 1st jet of aforesaid gas, called a primary jet, is injected to allow its contact with the fuel jet and to form the 1st incomplete firing. Note here that outlet gases, thereafter, contains, nevertheless, at least, one fraction of fuel. Note also that the 2nd aforesaid jet is injected at the distance of l1 from the fuel jet to allow firing together with the said 1sr fuel fraction existing in outlet gases after 1st firing. Oxygen containing gas with low oxygen content is injected at the distance l2 from the fuel jet providing the firing together with the said outlet gases after 1st firing, where l2>l1.

EFFECT: firing gas with low oxygen content.

25 cl, 1 dwg

FIELD: heating systems.

SUBSTANCE: invention refers to gas burners with separate air and gaseous fuel supply. The effect is achieved in gas burner (1) containing main metal housing (6), an inner tube for fuel gas, at least two outer tubes (10) for fuel gas, single tube (8) for supplying pre-heated air, fuel gas supply control system, refractory block (30) and a group of nozzles (20) which are located in a circumferential direction coaxially in relation to inner tube and meant for spraying pre-heated air into combustion chamber.

EFFECT: limit reduction of NOx concentration in exit combustion products.

29 cl,13 dwg

FIELD: heating.

SUBSTANCE: invention related to energy, particularly to burner devices and can be used in gas turbine equipment. Burner device consists of a case (1), a fuel nozzle (2), a front device (3), a fire tube (4). The burner device belongs to gas-turbine engine combustion chamber. The front device executed with holes for fuel nozzles installation (2). The fire tube (4) with the front device (3) located inside of the combustion chamber cage (5). Fuel nozzles (2) connected to a gas ring collector (6). In combustion chamber fire tube and cage (5) between wall area air nozzles (7) located radically. Air nozzles (7) connected to the common ring air collector (9). The air collector (9) located in the case (1).

EFFECT: invention allows to regulate primary air supply to the combustion chamber section during equipment operation, burning device design simplification, it operation safety stays constant, possibility of device change on the running gas turbine equipment.

1 dwg

FIELD: heating.

SUBSTANCE: invention relates to fuel combustion process. Fuel combustion method is implemented by means of oxygen-containing gas with high oxygen content, in accordance with which to combustion chamber there sprayed is fuel jet and at least two jets of oxygen-containing gas; at that, the first or primary jet of oxygen-containing gas is supplied through the hole having diametre D and sprayed around the above fuel jet in such quantity which allows providing the first incomplete fuel combustion; at that, gases formed as a result of the above first combustion contain at least some part of unburnt fuel, and the second jet of oxygen-containing gas introduced through the hole having diametre d and located at some distance 1 from the hole of introduction of the first or primary jet of oxygen-containing gas so it can be possible to enter into combustion reaction with the fuel portion which is contained in gases formed as a result of the above first incomplete combustion; at that, fuel jet opens inside the jet of primary oxygen-containing gas at some point located at some distance in backward direction from combustion chamber wall; at that, the above point is located at distance r from that wall, and oxygen-containing gas with high oxygen content is pre-heated at least to 300C. Ratio r/D has the value either lying within the range of 5 to 20, or lying within the range of 0.75 to 3, and ratio 1/d has the value equal at least to 2. Oxygen-containing gas with high oxygen content represents oxygen concentration which is at least 70% by volume. Fuel is subject to pre-heating up to temperature comprising at least 300C.

EFFECT: increasing fuel combustion efficiency.

15 cl, 1 dwg

FIELD: power engineering.

SUBSTANCE: burner for fuel combustion comprises fuel supply line. The fuel supply line consists of several fuel sections. Also each fuel section is connected to another section and is designed for supply of fuel flow. Further, the burner includes a fuel inlet section. This section has the first fuel inlet and the first fuel outlet located at a distance from the first fuel inlet. The fuel inlet section has the first through cross section area and is designed to supply fuel flowing into the first fuel inlet and coming out the first fuel outlet. The burner has an intermediate section of fuel with fuel inlet and outlet device, notably the fuel outlet device is located at a distance from the fuel inlet device. The intermediate fuel section is designed for supply of at least part of flow coming into the inlet fuel device and going out of the outlet fuel device and has the second through cross section area. The second through cross section area changes from the initial through cross section area in the fuel inlet device to different through cross section area in the fuel outlet device. The burner has the fuel outlet section. The fuel outlet section has the second inlet of fuel and the second outlet of fuel located at a distance form the second inlet of fuel. The fuel outlet section is designed for supply of at least part of fuel flow coming onto the second fuel inlet and going out the second fuel outlet and it has the third through cross section area. This third through cross section area in essence is uniform along the whole outlet section of fuel. The burner comprises the first line of oxidant with several oxidant sections. Each oxidant section is connected to another oxidant section. It is designed to supply flow of oxidant. It includes an oxidant pressure chamber letting though oxidant flow and having the fourth through cross section area. At least part of oxidant pressure chamber is located in essence at least next to a part of at least one inlet section of fuel, intermediate section of fuel and outlet section of fuel. The oxidant outlet section lets through at least part of oxidant flow and has the fifth through cross section area. Also the fifth through cross section area is less or equal to the fourth through cross section area and in essence is uniform along the whole outlet section of oxidant. At least part of oxidant outlet section in essence is positioned next to the fuel outlet section.

EFFECT: facilitating upgraded quality of fuel combustion and reduced level of nitrogen oxide exhaust into atmosphere.

28 cl, 19 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing acetylene and synthetic gas via thermal partial oxidation of hydrocarbons which are gaseous at temperatures used for preheating, in a reactor which is fitted with a burner with through holes, characterised by that the starting substances to be converted are quickly and completely mixed only directly in front of the flame reaction zone in through holes of the burner, where in the mixing zone within the through holes the average flow rate is higher than the propagation speed of the flame under the existing reaction conditions. The invention also relates to a device for realising the said method.

EFFECT: possibility of avoiding preliminary and reverse inflammations.

9 cl, 3 ex, 1 dwg

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