RU2473010C1 - Furnace - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: furnace comprises a combustion chamber with a vertical plane of symmetry, side walls with screen pipes arranged symmetrically relative to the vertical plane of symmetry, bottom and ceiling slabs, a rear wall with a window of combustion products discharge, a front wall with two main burners symmetrically arranged relative to the vertical plane of symmetry, having slot vertical nozzles to supply primary air and gas, arranged at the side of the vertical plane of symmetry of the chamber, slot vertical nozzles for introduction of secondary air arranged at the side of side walls with screen pipes, and also slot vertical spacers separating these nozzles, on the front wall under the main burners there is a burner installed, having a slot horizontal nozzle arranged at the bottom side for supply of secondary air, a slot horizontal nozzle arranged at the side of the main burners for primary air and gas supply, and also a slot horizontal spacer separating these nozzles.

EFFECT: invention makes it possible to reduce gas underburning with lower yield of nitrogen oxides.

3 dwg

Description

The invention relates to energy and can be used in boilers of thermal power plants and industrial boiler units operating on gaseous fuels.

A known furnace containing a combustion chamber with a vertical plane of symmetry, side walls with screen tubes placed symmetrically with respect to the vertical plane of symmetry of the chamber, a hearth and ceiling, a rear wall with an exit window of combustion products, a front wall with burners (L.N.Sidelkovsky, V .N. Yurenev. Steam Generators of Industrial Enterprises. M: Energy, 1978, p.185-187, Fig. 13-2). The disadvantage of this device is the high yield of nitrogen oxides with combustion products and underburning of fuel.

Known a furnace containing a combustion chamber with a vertical plane of symmetry, side walls with screen tubes placed symmetrically relative to the vertical plane of symmetry of the furnace, a hearth and ceiling, a rear wall with an exit window of combustion products, a front wall with two main symmetrically placed relative to the vertical plane of symmetry of the furnace burners having nozzles for discharging primary and secondary air and gas flows into the furnace (RF patent No. 2303193; F23C 1/12 of 04/10/2006; BI No. 20, 2007). The furnace provides a reduced yield of nitrogen oxides. The disadvantage of this device is the increased underburning of fuel with horizontal placement of the furnace with a limited height of the combustion chamber.

A known furnace containing a combustion chamber with a vertical plane of symmetry, side walls with screen tubes placed symmetrically with respect to the vertical plane of symmetry, a hearth and ceiling, a rear wall with an exit window of combustion products, a front wall with two main burners symmetrically placed with respect to the vertical plane of symmetry, having vertical slotted nozzles for supplying primary air and gas, placed on the side of the vertical plane of symmetry of the chamber, vertical slotted alny nozzles for introducing secondary air, placed on the side of the side walls with screen tubes, and also slotted vertical walls separating these nozzles (K. Osintsev. Method for reducing heat flow in the direction of burner embrasures / K.V. Osintsev // Electric stations, No. 11, 2009. - S.13-17). The device provides a reduced yield of nitrogen oxides with combustion products. The drawback of the furnace is the increased underburning of gas with a limited height of the combustion chambers used on boilers of small heat output.

The objective of the invention is the reduction of gas underburning with a reduced output of nitrogen oxides from a horizontal furnace with a limited height of the combustion chamber.

To solve the indicated problem in a furnace containing a combustion chamber with a vertical plane of symmetry, side walls with screen tubes placed symmetrically with respect to the vertical plane of symmetry, a hearth and ceiling, a rear wall with an exit window of combustion products, a front wall with two symmetrically placed with respect to the vertical plane symmetries of the main burners having slotted vertical nozzles for supplying primary air and gas placed on the side of the vertical plane and chambers, vertical slotted nozzles for introducing secondary air, placed on the side of the side walls with screen tubes, as well as vertical slotted walls separating these nozzles, according to the invention, an additional burner is installed on the front wall under the main burners, having a horizontal slotted nozzle for secondary air supply, a horizontal slotted nozzle for supplying primary air and gas, located on the side of the main burners, as well as a horizontal slot separating these nozzles ntalny pier.

When installing on the front wall under the main burners an additional burner equipped with a horizontal slotted nozzle for introducing secondary air, located on the hearth side, and a horizontal slotted nozzle for introducing primary air and gas, placed on the side of the main burners, as well as a horizontal slotted wall separating these channels provides the necessary time for complete burnout of the gas the residence time of the reagent components in the furnace at a low temperature level, active radiation heat transfer and min the level of activity of the formation of harmful nitrogen oxides, that is, the problem of the invention is solved.

The proposed furnace is schematically represented in the drawings.

Figure 1 shows a furnace with a combustion chamber having a vertical plane of symmetry parallel to the side walls, a view of the front wall with burners from the furnace; figure 2 is a longitudinal section along aa in figure 1; figure 3 is a horizontal section along BB in figure 1.

The furnace in FIGS. 1, 2, 3 comprises a combustion chamber 1 bounded by side walls 2, 3, a front wall 4, a rear wall 5, a flooring 6, a ceiling 7; the combustion chamber 1 has a vertical plane of symmetry γ, and the side walls 2, 3 are screen tubes 8, 9, respectively, and walls 2, 3 with pipes 8, 9 are symmetrical with respect to the plane γ; a window 10 for the exit of combustion products is made in the rear wall 5, and two main burners 11, 12, as well as one additional burner 13, are installed symmetrically with respect to the vertical plane γ on the front wall 4; main burners 11, 12 have slotted vertical nozzles 14, 15, respectively, for supplying primary air and gas, located on the side of the vertical plane of symmetry у, as well as slotted vertical nozzles 16, 17, respectively, for supplying secondary air, placed on the side of side walls 2, 3 with screen tubes 8, 9; wherein the nozzles 14, 15 are separated from the nozzles 16, 17 by vertical slotted walls 18, 19, respectively; an additional burner 13 is placed under the main burners 11, 12, while it has a horizontal slotted nozzle 20 for supplying secondary air located on the side of the hearth 6 of the combustion chamber 1, as well as a horizontal slotted nozzle 21 for supplying primary air and gas, located on the side of the main burners 11, 12; inside the burner 13, the nozzles 20 and 21 are separated by a wall 22; pipes 8, 9 are brought into the collectors 23, 24, 25, 26, respectively.

The operation of the furnace in figure 1, 2, 3 is carried out by feeding into the combustion chamber 1 flows of primary air and gas, as well as flows of secondary air; reagent flows are introduced into the chamber 1 through the main burners 11, 12 and an additional burner 13, and through the main burners 11. 12 primary air and gas are introduced through the burner nozzles 14, 15 along the vertical plane of symmetry γ, and secondary air through the nozzles 16, 17 along side walls 2, 3 with screen tubes 8, 9; secondary air is supplied through an additional burner 13 through a nozzle 20 along the hearth, and primary air and gas flows through a nozzle 21 from the side of the main burners 11, 12. When the fuel components of the gas interact with air oxygen, an oxidation reaction occurs with the release of heat; the latter due to radiation heat transfer is discharged to the pipes 8, 9 and the working medium, in particular water and steam circulating in the pipes 8, 9. The working medium enters the pipes 8, 9 through the collectors 23, 24, is discharged through the collectors 25, 26; while the water and steam are heated, and the resulting combustion products are cooled and discharged from the combustion chamber 1 through a window 10 in the rear wall 5. Subsequently, the combustion products are cooled in convective heating surfaces and are discharged through the chimneys into the atmosphere (these elements in Fig. 1, 2, 3 are not shown). Water in convective heating surfaces is heated to the required temperature or converted into steam and supplied to the consumer (not shown in Figs. 1, 2, 3).

When installing on the front wall 4 under the main burners 11, 12 an additional burner 13, equipped with a horizontal slotted nozzle 20 for introducing secondary air placed on the side of the hearth 6, and a horizontal slotted nozzle 21 for introducing primary air and gas placed on the side of the main burners 11 12, as well as a horizontal slotted dividing wall 22 separating these channels, provides the necessary residence time for the reagent components in the combustion chamber 1 to completely burn out the gas at a reduced temperature level, active heat exchange and a minimum level of activity of formation of harmful nitrogen oxides, that is, the problem of the invention is solved.

A positive effect with a reduction in gas underburning and the concentration of harmful nitrogen and carbon oxides is also achieved in devices that have additional screen pipes on the front and rear walls, ceiling and hearth ceilings.

The operation of these devices is similar to the operation of the furnace in figure 1, 2, 3.

The practical application of the invention is steam and hot water boilers of the DKVR type with various steam and heat output (in particular, from 2 to 25 tons of steam per hour). In comparison with existing fire chambers, the ecological characteristics of boilers are improved by reducing emissions of carbon and nitrogen oxides, and reducing fuel consumption.

Claims (1)

A furnace containing a combustion chamber with a vertical plane of symmetry, side walls with screen tubes placed symmetrically with respect to the vertical plane of symmetry, a hearth and ceiling, a rear wall with an exit window of combustion products, a front wall with two main burners symmetrically placed relative to the vertical plane of symmetry, having slotted vertical nozzles for supplying primary air and gas placed on the side of the vertical plane of symmetry of the chamber, vertical slotted nozzles pla for introducing secondary air, located on the side of the side walls with screen tubes, and also slotted vertical walls separating these nozzles, characterized in that an additional burner is installed on the front wall under the main burners, having a horizontal slotted nozzle for supplying secondary air located on the bottom side a horizontal slotted nozzle for supplying primary air and gas, located on the side of the main burners, as well as a horizontal slotted wall separating these nozzles.

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