RU2518759C1 - Oil-gas burner - Google Patents

Abstract

FIELD: energy industry.

SUBSTANCE: burner for combustion of gaseous and/or liquid fuel is used in steam and hot water boilers. The burner consists of a main burner with a unit for supplying gas fuel and with a device for supplying liquid fuel, a pilot burner and an ignition burner. The pilot burner with forced air supply is located in the housing of the main burner. When operating on the gas fuel the pilot burner is used to control the main burner flame. The sensor of the main burner flame, operating with the fuel oil, the photosensor is used. The ignition burner located in the housing of the main burner is used to ignite the flame of the pilot burner and the flame of the main burner, operating both on the gaseous and liquid fuels.

EFFECT: creation of a safe burner for high power boilers.

4 cl, 4 dwg

Description

The invention relates to energy, and in particular to a gas-oil vortex burner for burning gaseous and / or liquid fuel used in steam and hot water boilers of high power. Natural gas can be used as gaseous fuel, and fuel oil, diesel fuel or boiler fuel can be used as liquid fuel. Combined combustion of gaseous and liquid fuels is allowed for a short time during the period of switching from one type of fuel to another.

Known gas-oil burner designed for steam and hot water boilers of high power, adopted as a prototype (Boilers and steam generators (design characteristics of energy boiler units): A reference guide for course and diploma design of students of specialties 1005 - "Thermal power plants", 1007 - " Industrial heat power engineering ”/ Compiled by E.A. Boyko, A.A. Shpikov; KSTU, Krasnoyarsk, 2003, section 2.2“ Fireboxes for burning liquid and gaseous fuels ”, http://www.atit-group.ru/biblioteka/ ) Known burner consists of a main burner with a device for supplying gaseous fuel and with a device for supplying liquid fuel and a gas electric igniter. A device for supplying gaseous fuel is made in the form of a collector connected to a gas pipeline and gas-distributing pipes connected to the collector. A nozzle is used as a device for supplying liquid fuel. The burner contains central and peripheral air channels in which swirlers are located. The nozzle and gas electric igniter are located in a pipe located along the axis of the burner. The known source does not describe the means by which the flame of a gas-oil burner is controlled

The objective of the invention is to provide a safe burner for boilers of high power.

The technical result is achieved by the fact that the design of the proposed burner provides selective control of the main torch of the burner during burner operation on a multi-burner boiler.

For this, the following devices are provided in the burner:

- devices for supplying gaseous fuel;

- devices for supplying liquid fuel;

- an ignition burner designed to ignite the torches of the pilot and main burner in the ignition mode of the burner operating on gaseous fuel, and intended to ignite the torch of the main burner operating on liquid fuel;

- pilot flame control sensor;

- a pilot burner designed to control the flame of the main burner operating on gaseous fuel;

- pilot torch control sensor;

- a flame control sensor of the main burner operating on liquid fuel.

A sensor is used as a sensor for monitoring the torch of a pilot burner, the principle of which eliminates the possibility of another torch influencing it, for example, an ionization sensor.

As a sensor for monitoring the torch of the pilot burner, a sensor is used, the principle of which eliminates the possibility of another torch influencing it, for example, an ionization sensor.

A photo sensor is used as a sensor for monitoring the torch of the main burner running on liquid fuel.

The design of the burner is illustrated by the following drawings, where:

Figure 1 - frontal section.

Figure 2 - view A.

Figure 3 - view B.

4 is a schematic diagram of a gas-oil burner.

Gas-oil burner contains the following structural elements: 1 - housing; 2 and 3 - shells; 4 - the central air channel; 5 - peripheral air channel; 6 and 7 - cavity body; 8 - gas manifold; 9 - gas distribution pipe; 10 - nozzles; 11 - a device for supplying liquid fuel in the form of a nozzle; 12 - swirl in the central channel; 13 - swirl for air entering the peripheral channel; 14 - pilot burner; 15 - pilot burner; 16 - peephole; 17 - torch sensor of the main burner operating on liquid fuel; 18 - air chamber in the pilot burner; 19 - pipe for supplying air to the pilot burner; 20 - pipe for supplying gas in a pilot burner; 21 - swirl in the pilot burner; 22 - pilot torch control sensor; 23 - a device for electric ignition of a pilot burner; 24 - sensor control torch pilot burner; 25 - the main gas pipeline; 26 - the first shut-off valve (hereinafter first PZKA); 27 - the second shutoff valve (hereinafter the second PZKA); 28 - regulating rotary lock on the main gas pipeline; 29 - gas pipeline to the pilot burner; 30 - regulating rotary lock on a gas pipeline; 31 - air gate in front of the main burner; 32 - air gate in front of the pilot burner; 33 - gas pipeline to the pilot burner; 34 - the electromagnetic valve; 35 - control system; 36 - fuel oil line.

A gas-oil burner consists of a main burner with a device for supplying gaseous fuel and with a device for supplying liquid fuel, a pilot burner and an ignition burner.

The main burner is made with forced air supply. The shells 2 and 3 located in the housing 1 (Fig. 1) divide the inner space of the burner into central 4 and peripheral 5 air channels. The air entering the cavity 6 of the housing is directed to the central air channel 4, and the air from the cavity 7 of the housing is directed to the peripheral air channel 5.

A device for supplying gaseous fuel consists of a manifold 8 connected to a gas pipeline, connected to a manifold of gas distribution pipes 9 with nozzles 10. Gas distribution pipes 9 are located between two shells 2 and 3. The nozzles 10 are made of heat-resistant steel. Each nozzle 10 has the form of a tube, one part of which is fixed in the gas distribution pipe 9 and has an axis parallel to the axis of the burner, and the second part of the tube is inclined at an angle α to the axis of the first part of the tube and, therefore, directs gaseous fuel at an angle to the axis of the burner. For nozzles directed gaseous fuel towards the Central air channel, the angle α is selected in the range of 30-60 °. For nozzles directed gaseous fuel towards the peripheral air channel, the angle α is selected in the range of 5-45 °.

As a device 11 for supplying liquid fuel, a mechanical or steam-mechanical nozzle is used located in the pipe, the axis of which coincides with the axis of the burner.

An axial axial swirler 12 with profiled blades mounted at an angle of 45 ° to the main axis of the burner is located in the central air channel 4.

The air entering the peripheral channel 5 is twisted by a tangential swirl 13, the straight blades of which are located at an angle of 60 °.

Depending on the direction of the air twist in the burner, the axial swirler 12 and the tangential swirl 13 are executed in the right (for the burner of the right) or left (for the burner of the left) spin direction.

In the central air channel 4 (see figure 2) there is a pipe with a nozzle 11, a pilot burner 14, an ignition burner 15, an eye 16 and a sensor 17 of the main torch formed during the combustion of liquid fuel. A photosensor may be used as the torch sensor of the main burner running on liquid fuel.

Pilot burner 14 with forced air supply contains an air chamber 18, air into which is supplied through an individual pipe 19. In the air chamber 18 of the pilot burner there is a pipe 20 with a nozzle for supplying gas and a swirler 21 with profiled blades mounted at an angle of 35 ° to the axis of the burner . In order to ensure the constant power of the pilot burner and the stability of its torch, air and gas are supplied to the pilot burner 14 with a constant pressure (p = const). The air flow to the pilot burner is 2-5% of the total air flow. For guaranteed control of the main torch, the pilot burner 14 is located in the central air channel 4 so that the mouth of its torch during operation is located inside the embrasure of the burner. The pilot burner has a pilot burner flame sensor 22. In this case, a sensor is used, the principle of operation of which excludes the possibility of torches of other burners influencing it, for example, an ionization sensor.

When the burner is operated with gaseous fuel, the pilot burner is used to control the torch of the main burner. The torch of a continuously operating pilot burner 14 guarantees the presence of a torch of the main burner in all operating modes.

The ignition burner 15 provides automatic ignition of the torch of the pilot burner 14 and the torch of the main burner when the burner is running on gaseous fuel, or automatic ignition of the torch of the main burner when the burner is running on liquid fuel.

The ignition burner 15 is equipped with a device 23 (Fig. 4) for electric ignition and a sensor 24 for controlling the torch of the ignition burner, for example, an ionization sensor.

Before igniting the burner, for its further operation on gaseous fuel, the shut-off and control valves must be in the following state (see figure 4):

- the first PZKA 26 and the second PZKA 27 on the main gas pipeline 25 should be in the closed position;

- the air gate 31 in front of the main burner must be in the closed position;

- the rotary control valve 28 on the main gas pipeline 25 should be in a position corresponding to the minimum gas flow to the main burner;

- the electromagnetic valve 34 in front of the pilot burner 15 should be in the closed position;

- the rotary control valve 30 on the gas pipeline 29 and the air gate 32 in front of the pilot burner must be in such positions that set the pressure of gas and air, providing a stable torch of the pilot burner.

The operation of the burner on gaseous fuel is carried out in the following order:

- After carrying out preparatory measures in accordance with the requirements of the regulatory documentation for the preparation of the gas supply system for the burner and the air supply (blowing the gas pipe and boiler, pressure testing the shut-off valves, etc.) by opening the corresponding valves in the gas line, the pilot burner is ignited in front of the burner 15. To do this, open the first PZKA 26 on the main gas line 25, the electromagnetic valve 34 on the gas line 33 to the ignition burner and apply voltage to the device 23 for electric ignition of the ignition burner 15.

- After confirming the presence of the torch on the ignition burner using the ionization sensor 24 of the ignition burner, the second PZKA 27 is opened on the main gas pipeline 25. The pilot and main burner are ignited by the ignition torch, while the gas is supplied to the main burner through the control valve 28, which is in position corresponding to the minimum gas flow, and the air supply to the main burner occurs through the air gate 31 due to its loose closure.

- After receiving the signal from the sensor 22 of the pilot flame control of the pilot burner, indicating a stable torch on the pilot burner, stop the gas supply to the pilot burner by closing the electromagnetic valve 34.

At this point, the process of firing up a gaseous fuel burner ends.

Subsequently, during operation of the main burner in various modes, air and gas pressure are not adjusted to the pilot burner. Air and gas are supplied to the pilot burner with a constant pressure (p = const) for its operation with constant power.

Changing the power of the burner is carried out by the regulating shutter 28 and through the regulator of the ratio "gas-air" by the gate 31 of the main burner. If the torch of the main burner goes out or goes off, a continuously operating pilot burner ignites the torch of the main burner. The presence of continuous monitoring of the constantly operating torch of the pilot burner ensures the presence of the main torch of the burner. If the sensor 22 of the pilot flame control of the pilot burner indicates the absence of the pilot pilot torch, the gas supply to the entire burner will be cut off.

The shutoff and control valves are controlled automatically by the control system 35.

Before igniting the burner, for its further operation on liquid fuel, shut-off and control valves must be in the following condition;

- the electromagnetic valve 34 in front of the pilot burner 15 should be in the closed position;

- the air gate 31 in front of the main burner must be in the closed position;

- stop valves (not shown) on the fuel oil line 36 in front of the nozzle 11 should be in the closed position.

The operation of the burner on liquid fuel is carried out in the following order:

- To ignite the ignition burner 15, open the first PZKA 26 and the electromagnetic valve 34 on the gas line 33 and the voltage is supplied to the device 23 for electric ignition of the ignition burner.

- After confirming the presence of the torch on the ignition burner 15 using the sensor 24 for monitoring the torch of the ignition burner, the shut-off valves are opened in front of the nozzle 11 and the gate 31 in front of the main burner and the main torch is ignited by the ignition torch.

- After receiving the signal of the photosensor 17 about the presence of the main torch of the burner, the ignition burner 15 is turned off. In the future, the main torch of the burner is constantly monitored.

At this point, the process of firing up the oil-fired burner ends.

Successful tests were carried out on the reliability of ignition, stability and stability of operation, as well as on the determination of the stall characteristics of the flare of the declared gas-oil burner with a capacity of 37.2 MW at the heating boiler of TPP-21 of Mosenergo OJSC and with a capacity of 47.0 MW at Surgutskaya GRES-1. Burners are representative of the type of a series of gas-oil burners with a capacity of 12 MW to 110 MW. Tests have shown that the main and pilot burners provide reliable ignition and stable combustion of natural gas without extinction, separation and breakthrough of the flame in various operating modes. The inventive burner allows for a smooth kindling and a set load of the boiler with a relatively small initial gas flow. The introduction of gas-oil burners with pilot burners in conjunction with automatic gas equipment blocks allowed for deep unloading of a large-capacity boiler without compromising the reliability of the equipment. The removed stall characteristics of the burners showed a high degree of reliability of the burners even at very low (up to 0.01 kgf / cm ² ) gas pressures. At the same time, there is no need to extinguish the burners during unloading (on weekends and at night), which, as a rule, entails an abrupt change in gas flow. Gas-oil burners in conjunction with gas equipment units allow for a smooth decrease in gas flow without loss of temperature of sharp steam behind the boiler and provide deep unloading of the boiler and, as a result, compliance with the dispatch schedule of loads, to reduce gas consumption and ensure environmental requirements.

Stable operation of the pilot burner ensures guaranteed selectivity of control of torch torches on a multi-burner boiler to meet the requirements for reliable and safe operation of the boiler.

Claims (4)

1. Gas-oil burner containing a main burner with a device for supplying gaseous fuel and with a device for supplying liquid fuel and a pilot burner, characterized in that it further comprises a pilot burner with a sensor for controlling the torch of the pilot burner, a sensor for controlling the torch of the pilot burner and a sensor for controlling the torch main oil burner. 2. The burner according to claim 1, characterized in that a sensor is used as a torch control sensor of the pilot burner, the principle of which eliminates the possibility of another torch influencing it, for example, an ionization sensor. 3. The burner according to claim 1, characterized in that a sensor is used as a sensor for monitoring the torch of the pilot burner, the principle of which eliminates the possibility of another torch influencing it, for example, an ionization sensor. 4. The burner according to claim 1, characterized in that a photosensor is used as the flame control sensor of the main burner operating on liquid fuel.

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