RU2186301C2 - Heating boiler - Google Patents

Abstract

FIELD: heat power industry; applicable in heating of residential and production rooms, and preparation of hot water for household needs. SUBSTANCE: introduced into boiler internal space is heat-exchange member in the form of hollow L-shaped partition with widened upper part into which water-heating member of hot water supply is introduced. Part of gas conduit formed between rear side of hollow partition and internal walls of boiler framing jacket is separated by removable partition introduced through hole made in upper part of boiler framing jacket locked by a cover with heat reflector and condensate evaporator - gas turbulizer resting on lower part of gas conduit space. EFFECT: intensified heat exchange in gas conduit space due to improvement of heat transfer conditions, increased velocity of heat carrier in heating system. 4 dwg

Description

 The invention relates to heat engineering and can be used for heating residential, industrial premises and hot water for domestic use, which allows the use of a heating boiler in canteens, rural hospitals, farms, greenhouses and other premises.

 Known hot water boiler [1, 2], designed for heating and hot water supply, containing a firebox framed by a water jacket, connected to a window for the exit of combustion products. In the upper part of the furnace there are guide partitions, one of which is located transversely at a distance from the side wall of the furnace with the formation of a passage for combustion products, and the other partition is made in the form of a vertical open shell. It is installed between the transverse partition and the upper wall of the furnace, and the open section of the shell faces in the opposite direction to the passage mentioned above.

 To increase the efficiency of heat transfer, the boiler is equipped with additional partitions, one of which is installed transversely between the windows for the exit of combustion products, and the second is located longitudinally.

 A disadvantage of the known hot water boilers is that the opportunities to increase the efficiency of heat exchange between the partitions and the water filling the water jacket are not fully used, since it only increases the path of the combustion products and their residence time in the furnace space, and the heat exchange area remains unchanged .

 The heat transfer efficiency increases slightly only due to heat removal from the metal partitions to the walls of the water jacket in the upper part of the boiler. This nature of heat transfer does not contribute to the intensity of water circulation in the heating system.

 Of the known heating boilers, the closest in technical essence and the achieved results is a heating boiler [3], which contains a casing in the form of a water jacket framing the firebox and gas duct, equipped with hollow partitions connected with the cavity of the jacket and forming a labyrinth gas channel in the duct.

 A disadvantage of the known heating boiler with an increase in the number of heat exchange elements of more than two is: an increase in overall dimensions, complication of the design of the boiler, a decrease in manufacturability and a slight increase in efficiency, which is economically and technically not rational, in addition, it helps to reduce the temperature of the exhaust gases, which leads to increasing condensate formation and worsening conditions for removal of soot from the horizontal surfaces of the heating elements. The design of the boiler is sensitive to sudden changes in air velocity, which can lead to the suppression of the igniter and the cessation of the combustion of gaseous fuels.

 The invention is aimed at increasing the efficiency and intensity of heat exchange between the products of fuel combustion and heat transfer elements of the boiler design by increasing the area of convective heat transfer and turbulizing the flow of gaseous products of fuel combustion and reducing the overall dimensions of the boiler per unit power.

 This is achieved by the fact that in a known heating boiler, comprising a body in the form of a rectangular water jacket framing a furnace and a gas duct, provided with hollow partitions in communication with the cavity of the shirt and forming a labyrinth gas channel and a water heating element for hot water supply in the gas duct, into the internal volume of the boiler a heat-exchange element is introduced in the form of a hollow cavity of an L-shaped form with an expanded upper part. The ends of the heat-exchange element are connected to the inner wall of the framing shirt, forming a closed loop of the heat-transfer medium with the cavity of the framing shirt. This element divides the internal volume of the boiler into the furnace and flue space of the fuel combustion products. Moreover, a water heating element was introduced into the expanded upper part of the L-shaped partition to select hot water for domestic needs. A part of the gas duct formed between the rear side of the heat exchange element and the inner walls of the framing shirt is separated by a removable partition, which is inserted through the formed hatch in the upper part of the boiler framing jacket, rests on the condensate evaporator - gas turbulator installed in the lower part of the gas duct space and is fixed by the manhole cover with thermal reflector.

 The invention is illustrated by drawings, where figure 1 shows a longitudinal section of a heating boiler; figure 2 is a rear view of the boiler; figure 3 is a cross section of a heating boiler along aa; figure 4 is a section along BB.

The positions in the drawings indicate:
1 - framing shirt;
2 - heat transfer medium;
3 - hollow partition L-shaped (heat exchange element);
4 - furnace space;
5 - condensate evaporator - gas turbulator;
6 - aperture;
7 - pipe entrance to the boiler coolant;
8 - removable partition;
9 - flue space;
10 - chimney;
11 - pipe for the selection of hot water;
12 - hatch;
13 - manhole cover with a thermal reflector;
14 - pipe outlet from the boiler coolant;
15 - water heating element of hot water supply;
16 - flow of combustion products;
17 - pipe input water for heating;
18 - expansion upper part of the hollow partition;
19 is a vertical component of a hollow partition;
20 - the back side of the hollow septum;
21 - the front side of the hollow partition;
22 - the inner wall of the framing shirt;
23 - the outer wall of the framing shirt;
24 - bottom wall.

 To improve the technical parameters and properties of the heat transfer process, the following elements were introduced into the boiler: L-shaped hollow partition 3 with an expanded upper part 18, which acts as a heat exchange element, in which a hot water heating element 15, hatch 12, a manhole cover with a heat reflector is installed 13 and removable partition 8.

 The hollow partition of the L-shaped form 3 is made with different cross-sectional sizes: the expanded horizontal component 18 and the vertical component 19, equal to the cross-section of the framing shirt 1 of the boiler body, and divides the internal volume of the boiler into furnace 4 and the gas passage 9. The cavity of the heat exchange element 3 s the framing jacket of the boiler 1 form a closed loop of the heat transfer medium 2. A hatch 12 is created above the gas duct part of the boiler, through which a removable partition 8. is inserted. A removable partition 8 is installed from the bottom it is pumped onto the condensate evaporator — gas turbulator 5, and from above it is fixed by the manhole cover 13 with a heat reflector and divides the gas duct between the back of the hollow partition 20 and the inner walls of the framing shirt 1 into two equal parts.

 The hollow partition 3, the removable partition 8 with the condensate evaporator — gas turbulator 5 and the opening 6 form a labyrinth for the gaseous products of fuel combustion 16 to exit into the chimney 10 (indicated by arrows). The separation of the gas passage 9 by a removable partition 8 lengthens the path of the passage of combustion products. The condensate evaporator - gas turbulator 5 when passing the gaseous products of fuel combustion through the opening 6 increase their turbulization. This contributes to a more efficient heat transfer of the products of combustion of fuel due to their washing of a larger area of the inner surface of the framing jacket 22 and the back side 20 of the heat exchange element 3, turbulization by the flow of products of combustion of fuel. This leads to an increase in the efficiency of the boiler.

 The hollow partition of the L-shaped form includes the advantages of vertically and horizontally located heat-heating cavities. The vertically component of the L-shaped heating element is made with a cavity thickness equal to the cavity thickness of the framing shirt. It provides the most favorable conditions for the circulation of the coolant due to the largest temperature difference between the lower and upper horizontally constituent parts. The bottom wall 24 of the horizontally component of the expanded part of the heat exchange element 3 is installed perpendicular to the upward heat flow of the fuel combustion products. This provides the best conditions for convective and radial heat exchange between the gaseous products of fuel combustion and the heating element in the furnace space. Due to the relatively small volume of the coolant in the horizontally constituent part of the heating element and the location in the high temperature region of the exhaust gases of the fuel combustion products, it undergoes intense heating and rapid thermal expansion. As a result of this, a directed flow is created, which contributes to an increase in the pressure difference at the inlet 7 and outlet 14 of the heating boiler and the improvement of heat transfer conditions to the hot water heating element 15.

 The volume of the horizontal component of the expanded cavity of the heat-exchange element 3 is selected from the condition that prevents local boiling of the heat-transfer medium in it, in order to prevent a decrease in the rate of movement of the heat-transfer medium as a result of the formation and penetration of air bubbles in the heating system and the formation of scale on the lower wall 24, which reduces heat transfer from combustion products to the coolant. This eliminates the reduction in the efficiency of the heating boiler in the process of increasing the operating time. The dimensions of the hot water supply element 15 and the selection of hot water are selected from conditions that prevent the deceleration of the circulation of the coolant and reduce the efficiency of the heating system.

 When firing up a heating boiler, a sharp decrease in the temperature of the air in the room where the boiler is located, lowering the temperature of the exhaust gases of the fuel combustion products, condensation forms on the inner walls of the framing shirt. Condensate with the products of fuel combustion forms chemically active compounds that contribute to corrosion of the walls of the framing shirt, reducing the operational life of the boiler, deteriorating heat transfer to the coolant 2 and reducing the efficiency of the boiler. As the condensate increases, it collects at the bottom of the gas duct 9. To remove condensate, a condensate evaporator — a gas turbulator — is introduced into the boiler. Condensate from the gas duct 9 flows into the evaporator — turbulator 5. Condensate is converted to vapor from the liquid state in the evaporator 5 due to heating of the combustion products with its exhaust gases, it returns to the chimney space 9 and, together with the gaseous products of fuel combustion, is released into the atmosphere. The absence of condensate increases the life of the boiler without reducing efficiency.

 The manhole cover 13 with a thermal reflector provides fixation of the partition 8, creates a directed movement of gaseous products of fuel combustion through the maze and reduces the loss of thermal energy through the manhole cover.

 The heating boiler operates as follows. The heat transfer medium 2 through the pipe 7 is fed into the lower part of the framing jacket of the boiler. In the furnace space 4, fuel is burned. The combustion products form a gaseous stream 16, which washes the inner walls 22 of the framing shirt 1, the front side 21 of the hollow partition L-shaped 3, enters the gas duct 9, where it washes the upper inner wall of the framing shirt, the back side 21 of the hollow partition, the vertical walls of the framing jacket in the chimney space 9, heats them and at the same time coolant in contact with them 2. Having transferred to these elements the bulk of the thermal energy, the gaseous stream of combustion products goes into smoke od.

 The coolant located in the upper part of the heat exchange element 3 gives off part of the thermal energy to the water circulating through the hot water supply element 15, which is used for domestic purposes. When the heating system is turned off, all the thermal energy of the boiler can be used for hot water supply at any water pressure in the water supply network.

 This design of the heating boiler provides the most efficient heat transfer in the heat exchange elements by increasing the heat transfer area without increasing the overall dimensions and, due to the presence of a hatch 12, a removable partition 8 and a removable condensate evaporator - gas turbulizer 5, provides easy access to all sections of the chimney space for cleaning soot.

The use of new elements in the boiler for heating and hot water supply compares favorably with the proposed boiler, as it allows:
- intensify heat transfer in the furnace and flue space by improving the conditions of heat transfer from the combustion products to the heating elements;
- increase the rate of circulation of the coolant by increasing the heating rate in the heat exchangers of the elements;
- to reduce the dimensions and consumption of materials per unit capacity of the heating boiler through the use of a L-shaped hollow partition and the creation of a complex labyrinth of movement of fuel combustion products, increasing the path of their passage and the washing area;
- increase the efficiency of the heating boiler;
- improve the reliability of the boiler by eliminating the blowing of the igniter during sudden changes in the flow of atmospheric air;
- improve service conditions during operation.

Sources of information
1. Copyright certificate 1820156 A1, F 24 H 1/26, F 23 M 9/06, BI 21, 1993.

 2. Copyright certificate 1733867 Al, F 24 H 1/40, 18, 1992.

 3. RF patent 2122688, F 24 N 1/00, BI 33, 1998.

Claims (1)

 A heating boiler for heating residential, industrial premises and hot water for domestic use, comprising a body in the form of a rectangular water jacket framing the firebox and gas duct, equipped with hollow partitions in communication with the shirt cavity and forming a labyrinth gas channel in the duct, and a water heating element for hot water supply, characterized in that a heat-exchange element is introduced into the internal volume of the boiler in the form of a hollow partition of a L-shape with an expanded upper part and separating the inside the volume of the boiler into the furnace and gas passage space of the products of fuel combustion, moreover, a water heating element of hot water supply is introduced into the expanded upper part of the cavity of the L-shaped partition, and the part of the gas channel formed between the back of the hollow partition and the inner walls of the framing shirt is divided by a removable partition introduced through the created hatch in the upper part of the framing jacket of the boiler, fixed by a lid with a heat reflector and resting on the gas installed in the lower part flow space condensate evaporator - gas turbulator.

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