RU2190154C2 - Cyclone furnace extension (alternatives) - Google Patents

Abstract

FIELD: power engineering; fuel combustion in swirl chambers. SUBSTANCE: cyclone furnace extension has combustion chamber with axial-flow injector for high-reactivity fuel with peripheral swirl generator, ducts for tangential supply of air and low-reactivity fuel through adjacent ports in combustion chamber wall; air supply port is first along tangential flow swirling path. Furnace extension has at least two air feed ports over cross-sectional area circumference; adjacent ports are disposed in bottom part of combustion chamber and have end swirl chamber. Furnace extension may also have combustion chamber with high-reactivity fuel injector, air feed duct around combustion chamber walls, end swirl chamber, and low- reactivity fuel supply device in the form of axial annular channel passed through swirl chamber and through end section of combustion chamber; mentioned annular channel has in addition axial peripheral swirl generator and blade-type swirler inside channel; combustion- channel walls are provided with ports for tangential air feed from duct to combustion chamber. Proposed design ensures steady flame ignition and optimal control of burning process thereby eliminating pulsations and flame failure. EFFECT: enhanced quality of mixture produced and flow turbulence inside combustion chamber; reduced slag formation. 9 cl, 5 dwg

Description

 The invention relates to energy and can be used to burn fuel in vortex chambers.

 The most widespread cyclone pre-furnaces with tangential fuel supply. Thus, a cyclone pre-furnace is known, containing a combustion chamber with an axial nozzle of highly reactive fuel with a peripheral swirl, a box for tangential air supply through the windows in the wall of the combustion chamber (see SU 1508048, F 23 C 5/32, 1989).

 This preheater is not intended to burn pulverized fuel.

 A known cyclone pre-furnace containing a combustion chamber, an end vortex chamber, radially arranged openings for air supply and a box for tangentially supplying low-reaction fuel through windows in the wall of the combustion chamber, wherein the fuel supply window is located above the air supply openings (US 4351251, F 23 D 1/02, 1982).

 The specified invention does not allow to avoid pulsations and flame breakage.

 The closest analogue to the first embodiment of the invention is a cyclone pre-furnace containing a combustion chamber with an axial burner of highly reactive fuel with a peripheral swirl, ducts for tangential air and low-reaction fuel through the windows in the wall of the combustion chamber, the windows being adjacent, and the window for air supply being located first along the tangential swirl of the flow (SU 1185015, F 23 C 1/10, 1985).

 The disadvantages of this invention are the instability of the ignition of the torch and poor regulation of the combustion process and, as a result, the pulsating nature of the combustion up to the failure of the torch, poor mixture formation due to low turbulence, insufficient self-cleaning and sedimentation of slag on the walls of the chamber.

 The closest analogue for the second option is a cyclone pre-furnace containing a combustion chamber with an axial nozzle of highly reactive fuel, an air supply box around the walls of the combustion chamber, an end vortex chamber, and a device for supplying low-reaction fuel in the form of an axial annular channel passing through it and the end part of the combustion chamber (US 4492171, F 23 D 1/02, 1985).

 The disadvantages of this invention are the instability of the ignition of the torch and poor regulation of the combustion process and, as a result, the pulsating nature of the combustion up to the failure of the torch, poor mixture formation due to low turbulence, insufficient self-cleaning and sedimentation of slag on the walls of the chamber.

 The objective of the invention is to stabilize the ignition of the flame and improve the regulation of the combustion process, which will avoid pulsation and flame failure, increase the quality of mixture formation and flow turbulence inside the combustion chamber, and reduce slag formation.

 The problem is solved in that the cyclone pre-furnace contains a combustion chamber with an axial nozzle of highly reactive fuel with a peripheral swirl, ducts for tangential air supply and low-reaction fuel through windows in the wall of the combustion chamber, the windows being adjacent, and the air supply window located first along the tangential swirl the stream, in addition, the pre-furnace contains at least two windows for supplying air around the circumference of the cross section, and adjacent windows are located in the lower part of the combustion chamber, and will have an end vortex chamber.

 Windows for supplying air are evenly spaced around the circumference of the combustion chamber.

 The windows are divided into separate sections along the length of the chamber.

 The pre-furnace contains a device for regulating the cross-sectional area of windows.

 The sections of the window are equipped with separate devices for regulating the cross-sectional area of the window.

 This problem is also solved by the fact that the cyclone pre-furnace contains a combustion chamber with an axial nozzle of highly reactive fuel, an air supply box around the walls of the combustion chamber, an end vortex chamber, and a device for supplying low-reaction fuel in the form of an axial annular channel passing through it and the end part of the combustion chamber, which additionally contains an axial peripheral swirler and a blade swirl inside the channel, and in the walls of the combustion chamber there are windows for tangential air supply from the box ba into the combustion chamber.

 The peripheral swirl is made scapular.

 The pre-furnace contains an annular window for supplying air located around the axial annular channel for supplying low-reaction fuel.

 The annular window contains a peripheral scapular swirler.

 Figure 1 shows a longitudinal section of a cyclone pre-furnace with a tangential feed of fuel.

 Figure 2 is a cross section aa in figure 1.

 Figure 3 shows a longitudinal section of a cyclone pre-furnace with axial fuel supply.

 Figure 4 is a cross section bb in figure 3.

 Figure 5 - device for regulating the cross-sectional area of windows.

 According to the first embodiment, the cyclone pre-furnace (with tangential fuel supply) contains a lined combustion chamber 1 with an axial fuel oil nozzle 2 and with a peripheral blade swirl 3, duct 4 for tangential air supply through windows 5 made in the wall of the combustion chamber 1, an end vortex chamber 6 .

 Low-reaction pulverized coal fuel is supplied through windows 7 made in the wall of the combustion chamber 1 from ducts 8 of the tangential feed. Windows 5 and 7 are adjacent and are located at the bottom of the combustion chamber 1. Windows 5 for air supply are evenly spaced around the circumference of the combustion chamber 1. Windows 5 and 7 are divided along the length of the combustion chamber 1 into separate sections. The expansion of the possibility of regulating the combustion process can be carried out by adjusting the cross-sectional area of the windows 5 for supplying air using a control device, in particular using a rotary valve 20.

 During operation, the pre-furnace air is supplied to the duct 4, the end vortex chamber 6 and the peripheral blade vortex 3, as well as through the windows 5 and enters the combustion chamber 1, where it is mixed with the heated pulverized-coal air mixture supplied through the ducts 8 through the windows 7.

 The cyclone pre-furnace according to the second embodiment (with axial fuel supply) comprises a combustion chamber 9 with an axial fuel oil nozzle 10, an air supply box 11 around the walls of the combustion chamber 9, an end vortex chamber 12, a device for supplying low-reaction fuel (pulverized-coal air mixture) in the form of an axial annular channel 13 with a receiving hopper 14 for supplying a pulverized-coal air mixture. The channel 13 is made around the axial nozzle 10 and is equipped with an axial peripheral blade swirl 15. The windows 16 for tangential air supply are made in the lined walls of the combustion chamber 9. An additional blade swirl 17 is located inside the axial annular channel 13, and an annular window 18 for supplying air with its own peripheral blade swirl 19 is made around the axial annular channel.

 During operation, the preheater air is supplied to the duct 11 of the air supply, where it is divided and enters the end vortex chamber 12 and through the windows 18 and 16 into the combustion chamber 9, where it is mixed with the pulverized coal mixture supplied from the hopper 14.

 The above-mentioned pre-furnaces are launched on fuel oil, after heating the lined walls of the combustion chamber, pulverized coal fuel is supplied. Moreover, simultaneous and alternate burning of fuel oil and coal dust is possible.

Claims (9)

 1. A cyclone pre-furnace containing a combustion chamber with an axial nozzle of highly reactive fuel with a peripheral swirl, ducts for tangential air supply and low-reaction fuel through windows in the wall of the combustion chamber, the windows being adjacent, and the air supply window being located first along the tangential swirl of the flow, characterized in that it contains at least two windows for supplying air around the circumference of the cross section, wherein adjacent windows are located in the lower part of the combustion chamber, and contains an end window revuyu chamber.  2. The pre-furnace according to claim 1, characterized in that the windows for supplying air are arranged uniformly around the circumference of the combustion chamber.  3. The pre-furnace according to claim 1, characterized in that the windows are divided into separate sections along the length of the chamber.  4. The pre-furnace according to claim 1, characterized in that it comprises a device for regulating the window cross-sectional area.  5. The pre-furnace according to paragraphs. 3 and 4, characterized in that the sections of the window are equipped with separate devices for regulating the cross-sectional area of the window.  6. A cyclone pre-furnace containing a combustion chamber with an axial nozzle of highly reactive fuel, an air supply box around the walls of the combustion chamber, an end vortex chamber, and a device for supplying low-reaction fuel in the form of an axial annular channel passing through it and the end part of the combustion chamber, characterized in that the axial annular channel for supplying low-reaction fuel further comprises an axial peripheral swirler and a blade swirl inside the channel, and windows for the combustion chamber are made tangential air supply from the duct to the combustion chamber.  7. The pre-furnace according to claim 6, characterized in that the peripheral swirl is made scapular.  8. The pre-furnace according to claim 6, characterized in that it comprises an annular window for supplying air located around the axial annular channel for supplying low-reaction fuel.  9. The pre-furnace according to claim 8, characterized in that the annular window contains a peripheral scapular swirler.

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