RU209657U1 - WEATHER BOILER - Google Patents

Abstract

The utility model relates to the field of thermal power engineering and can be used in power boilers, waste heat boilers of metallurgical furnaces for cooling and partial purification of high-temperature dusty gases with utilization of their heat to generate steam. The technical problem to be solved by the utility model is to maintain the efficiency of the waste heat boiler by constantly removing dust from the convective heat exchange surfaces from the gas flow, eliminating operating costs associated with the need to manually clean the convective surfaces, and increasing the reliability and efficiency of work. cleaning devices. The stated technical problem is achieved by the fact that in the waste heat boiler containing radiation, convective gas ducts with enclosing surfaces and convective surfaces, made in the form of suspended coil screens or blocks of thermosiphons, inside the gas ducts on the working part or outside the gas ducts on the protruding part, a belt is installed on each convective surface. An "anvil beam" is attached to the belts of convective surfaces in the amount of two to ten pieces outside the enclosing surfaces. An inductor of the magnetic-pulse cleaning system is installed in the gap between the “anvil beam” and the boiler frame beam and attached to the boiler frame beam, and the “anvil beam” is attached from above and (or) to the side to the belts of convective surfaces. The passages of convective surfaces and belts through the enclosing surfaces are made through openings. Sealing elements are installed on the openings.

Description

The utility model relates to the field of thermal power engineering and can be used in power boilers, waste heat boilers of metallurgical furnaces for cooling and partial purification of high-temperature dusty gases with utilization of their heat to generate steam.

Known waste heat boilers for non-ferrous metallurgy furnaces ISASMELT and Ausmelt OSCHATZ.

Known waste heat boilers contain a radiant and sequentially installed convective flue, inside which there are convective heating surfaces in the form of serpentine hanging screens. On the enclosing surfaces of the radiation flue and convective surfaces for cleaning from external deposits formed during the deposition of dust from the exhaust gases of the metallurgical unit, devices for forced impact cleaning are installed. The devices are made in the form of group and individual electromechanical drives with executive bodies in the form of falling hammers, causing mechanical disturbances, leading to the collapse of the formed deposits.

The disadvantages of the known waste heat boiler include high operating costs for maintenance and repair of electromechanical drives and the lack of adjustment of disturbing forces.

A device for cleaning the surface according to patent No. 2153403 (Method for cleaning surfaces from various kinds of deposits and a device for its implementation, Bortkevich S.P., Gordienko V.M., Ivanov V.K., Matvienko O.V.) is known.

The device contains a source of high-voltage direct voltage, a discharge circuit consisting of a storage capacitor, a shunt diode, the cathode of which is connected to the positive terminal of the capacitor, a switch, a flat inductor (inductor) made in the form of a spiral, and an armature in the form of a sheet. The armature is rigidly fixed on the outer surface opposite the inner surface on which deposits are formed, with a gap to the inductor. And the inductor is mounted on a base, rigidly fixed on the surface to be cleaned. With a short-term exposure to the electromagnetic field of the inductor and armature, mechanical force impulses arise, leading to local elastic deformation of the surface on which the armature is fixed, and separation of the settled material during the reverse movement of the surface. Single mechanical impulses must have amplitudes not exceeding the values at which mechanical stresses in the surface to be cleaned reach the fatigue limit or the cyclic strength limit. Installing an armature with a gap relative to the inductor ensures the absence of a mechanical obstacle to the surface to be cleaned during its reverse movement under the action of elastic forces and allows you to change the inductance of the inductor by adjusting the gap. In addition, the presence of a gap between the armature and the inductor protects the inductor from mechanical influences leading to its destruction, and helps to increase its service life.

The disadvantage of the design is the installation of a magnetic-pulse cleaning system only on structures with relatively cold surfaces with a temperature of ~20-50°C, and having a slight transverse longitudinal rigidity, mainly made of sheet steel.

A device is known according to patent No. 2142855, relating to an electrostatic precipitator device designed to tap one or more collecting electrodes arranged vertically in one or more parallel rows, and containing for each row a horizontal carrier element to which the upper ends of the collecting electrodes and a tapping mechanism are attached, containing a tapping agent, such as a hammer and an "anvil".

The tapping force is created by a hammer, which transmits a directed blow through the "anvil" to the collecting electrodes, a disturbing effect in the form of a shock wave that propagates through them. The layer of dust accumulated on the collecting electrodes loosens and falls off.

The disadvantage of the device is the presence of a complex mechanical drive located in a dusty gas environment with a high temperature t=300-400°C, low reliability, high operating costs for maintenance and repair.

The closest in technical essence is a waste heat boiler according to a utility model patent No. 100589 (Waste heat boiler, Dobrynin V.V., Terentyev A.S., Krekov A.G.).

Waste-heat boiler containing radiation and convective gas ducts, with enclosing surfaces, consisting of heat exchange panels, and thermosyphons with refrigerators, having upper and lower collectors installed in the openings of the ceiling screen, while the radiation and convective gas ducts are equipped with branch pipes for connecting to a pulsed gas generator for dust cleaning.

The disadvantages of the known waste heat boiler include the low efficiency of gas-pulse cleaning to remove dust deposits from convective surfaces formed during the movement of high-temperature dusty gases from the metallurgical unit, and with a decrease in the heat transfer capacity of heat exchange surfaces, the need for manual cleaning arises.

The technical problem to be solved by the utility model is to maintain the efficiency of the waste heat boiler by constantly removing dust from the convective heat exchange surfaces from the gas flow, eliminating operating costs associated with the need to manually clean the convective surfaces and increasing the reliability and efficiency of the device. cleaning.

The stated technical problem is achieved by the fact that in the waste heat boiler containing radiation, convective gas ducts with enclosing surfaces, and convective surfaces made in the form of suspended coil screens or blocks of thermosiphons, inside the gas ducts on the working part or outside the gas ducts on the protruding part, a belt is installed on each convective surface. An "anvil beam" is attached to the belts of convective surfaces in the amount of two to ten pieces outside the enclosing surfaces. An inductor of the magnetic-pulse cleaning system is installed in the gap between the “anvil beam” and the boiler frame beam and attached to the boiler frame beam, and the “anvil beam” is attached from above and (or) to the side to the belts of convective surfaces. The passages of convective surfaces and belts through the enclosing surfaces are made through openings. Sealing elements are installed on the openings.

The claimed utility model is illustrated by drawings, where

in fig. 1 - general view of the waste heat boiler;

in fig. 2 - installation unit of the magnetic-pulse cleaning inductor;

in fig. 3 - node of the passage of the convective surface through the ceiling screen;

in fig. 4 - the node of the passage of the belt of the convective surface through the enclosing wall.

The waste heat boiler (Fig. 1) contains a radiation flue 1 with vertical enclosing surfaces 2, with a ceiling screen 3 and convective surfaces 4, a transitional flue 5, a convective flue 6 with vertical enclosing surfaces 2, a ceiling screen 3 and convective surfaces 4.

The working part of the convective surfaces 4 is installed inside the radiation 1 and convective 6 flues.

Fig. 2. On each working part of the convective surface 4 inside the gas ducts 1, 6 or on its protruding part outside the ceiling screen 3, a belt 7 is installed. To the belts 7 of the convective surfaces 4 in the amount of two to ten pieces outside the enclosing surfaces 2 and the ceiling screen 3 the "beam-anvil" 8 is attached. In the gap between the "beam-anvil" 8 and the beam 9 of the boiler frame, an inductor 10 of the magnetic-pulse cleaning system 11 is installed and attached to the beam 9 of the boiler frame. "Beams-anvils" 8 are attached to the belts 7 from above and (or) on the side to excite an active force with a vector in the vertical and (or) horizontal direction.

Fig. 3. The passage of convective surfaces 4 through the ceiling screen 3 is made through openings with the installation of sealing elements in the form of lens compensators 12.

Fig. 4. The passage of the belts 7 of the convective surfaces 4 is made through the openings of the vertical enclosing surfaces 2 through the gland seal 13.

The enclosing heat exchange surfaces 2 of the radiation 1, convective flues 6, convective surfaces 4 are supported by load-bearing building beams 9 of the boiler frame.

The waste heat boiler works as follows.

Dusty process gases leaving the metallurgical unit with a temperature of 1200-1700°C enter the radiation flue 1 of the waste heat boiler.

In the radiation flue 1 due to radiation gases transfer heat to the vertical enclosing surfaces 2 and enter the convective surfaces 4 of the radiation flue 1 with a temperature of 900-1100°C.

From the flow of exhaust gases with a relatively low speed, dust settles and dense deposits form on the convective surfaces 4. Gases with a temperature of 800-900 ° C through the transitional gas duct 5 enter the convective gas duct 6, where they give off their heat to the enclosing surfaces 2 and convective surfaces 4 .

On the convective surfaces 4 of the convective flue 6, dust and deposits also occur. After the gases are cooled in the convective flue 6, the gases are removed from the boiler at a temperature of 400-450°C.

The deposits formed on the convective surfaces 4 are thermal resistance to heat transfer and significantly impair the thermal performance of the boiler and the efficiency of its operation.

When the magnetic-pulse cleaning 11 is turned on, the discharge current flowing through the inductor 10 induces an electromagnetic field in the inductor 10, which, in turn, induces an eddy current and an electromagnetic field in the “anvil beam” 8. Interaction of pulsed magnetic fields created by the discharge and induced currents , leads to the emergence of an active impulse force with a vector in the vertical or horizontal direction, pushing the inductor 10 and the "beam-anvil" 8. The resulting reactive force is transferred to the beams 9 of the frame.

Since the "beam-anvil" 8 is rigidly fixed on the belts 7 of the convective surfaces 4, the latter is exposed to a disturbing force, which is controlled by the discharge current of the inductor 10.

Within a short time interval, the “anvil beam” 8, starting from the inductor 10, excites longitudinal and transverse stress waves in the metal in the pipes of the convective surfaces 4, while shear stresses appear between the surface of the pipes of the convective surfaces 4 and deposits, and elastic forces tending to return the surface to its original position. Under the action of the elastic force, the surface of the pipes, without experiencing any resistance, except for the adhesion force of the adhering material, returns to its original position at high speed. In this case, the cleaned surface of the pipes is separated from the adhering material, and thereby effective cleaning of the entire convective surface 4 is achieved. The stored potential energy of the magnetic-pulse cleaning system and the disturbing force must have amplitudes not exceeding the values at which the mechanical stresses in the surface being cleaned reach the limit fatigue or cyclic strength limit.

The inductor 10 is not subject to thermal effects, because the temperature of 250-300°C of the convective surfaces 4, due to the thermal conductivity resistance of the "beam-anvil" 8, is not transferred to the inductor 10.

Claims (3)

1. Waste heat boiler containing radiation, convective gas ducts with enclosing surfaces and convective surfaces, characterized in that on each working part of the convective surface inside the gas ducts or on its part protruding beyond the ceiling screen, a belt is installed, and to the belts of convective surfaces in the amount of two to ten pieces outside the enclosing surfaces, an “anvil beam” is attached, in the gap between which and the boiler frame beam, an inductor of the magnetic-pulse cleaning system is installed and attached to the boiler frame beam. 2. The waste heat boiler according to claim 1, characterized in that the "anvil beams" are attached to the belts from above and (or) from the side. 3. The waste heat boiler according to claim 1, characterized in that the passages of the convective surfaces and belts through the enclosing surfaces are made through openings with sealing elements.

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