RU209257U1 - Solid fuel boiler of long burning - Google Patents

Abstract

SUBSTANCE: long-burning solid fuel boiler contains a body with double walls forming a heat carrier tank, a fan, air ducts, a chimney outlet, a loading door, an unloading door, an ash pan door, a heat exchanger door, nozzles, an air supply window, grate bars, a heat exchanger located above the combustion chamber, and ash chamber. The boiler heat exchanger is made in the form of a horizontally located stepped channel of rectangular section, the steps of which are arranged in one row, a pair of short sides of the rectangular section of the channel is located horizontally, and a pair of long sides of the rectangular section of the channel is located vertically. The front end wall of the heat exchanger is made at an angle to the horizontal and is equipped with a hatch, access to which is provided through the loading door. 4 w.p. f-ly, 5 figs.

Description

The utility model relates to the field of heating, namely to fuel combustion devices in solid fuel boilers.

A long-burning solid fuel boiler is known (see patent RU 29989U1), including a housing with double walls forming a coolant tank, a combustion chamber and an ash-blowing chamber with doors and a two-stage heat exchanger located behind the chambers, the cavities of the vertical screens of which are connected to the coolant tank. The disadvantage of the known technical solution is the low efficiency of heat transfer due to the presence in the boiler system of only natural air convection, the lack of artificial ventilation does not allow to control the combustion process. Also, a disadvantage is the accumulation of a large amount of condensate in the lower part of the heat exchanger, caused by prolonged and uneven heating of the coolant in the boiler, as a result of the fact that hot flue gases, passing through the heat exchanger from top to bottom, come into contact with the cold part of the heat exchanger. The disadvantages of the design of the known boiler can also be attributed to the increased complexity of servicing the boiler, due to the need for frequent cleaning of the heat exchanger from combustion products.

Known solid fuel boiler long burning (see patent RU 168146 U1), including a housing with double walls forming a coolant tank, a combustion chamber with a door and a damper, an ash chamber, grates, a heat exchanger located above the combustion chamber and made in the form of a stepped channel, walls which are inclined relative to the horizontal plane and the chimney. Compared with the previous technical solution according to patent RU 29989 U1, the known boiler is free from the disadvantage of condensate formation due to the fact that the heat exchanger is located in the upper part of the boiler above the combustion chamber, where the coolant is heated more quickly and evenly. The disadvantages of the known technical solution are the absence of any device designed to regulate the flow of air into the combustion chamber, as well as low efficiency due to frequent clogging of the heat exchanger surfaces.

The closest technical solution adopted in this application for the prototype is a solid fuel boiler for long burning according to patent RU 196392 U1. The well-known boiler includes a body with double walls forming a coolant tank, a fan, inlet and outlet pipes for supplying and removing coolant, a chimney, a combustion and ash chambers separated by a grate and a heat exchanger located above the combustion chamber and made in the form of a vertically arranged stepped channel rectangular section. The presence of a fan in the design of the known boiler significantly improves the process of supply and distribution of air into the chambers of the boiler. A significant disadvantage of the known boiler is the design of the heat exchanger, in which the bottom of the channel is formed by the widest side of the channel, and the short sides of the channel form its height. This design leads to the fact that a significant part of the combustion products coming from the combustion chamber to the heat exchanger, due to the small height of particle deposition, does not have time to leave the channel through the chimney and settles at the bottom of the channel. This leads to a deterioration in heat transfer and a rather rapid decrease in the efficiency of the boiler and, accordingly, to additional operations to clean the boiler. The disadvantages of the prototype are the design features that do not allow the heat exchanger channel to be made of more than four stages, which leads to a limitation in terms of power and dimensions of the known boiler options. In this design, boilers with a power of over 150 kW require an increase in the number of heat exchanger stages and are too high and inconvenient to operate and maintain.

The objectives of this utility model is to develop a long-burning solid fuel boiler devoid of the shortcomings of known technical solutions, increase efficiency, and reduce labor costs for its maintenance.

The problem is solved by creating a long-burning solid fuel boiler containing a body with double walls forming a coolant tank, a chimney outlet, a loading door, an unloading door, an ash pan door, an air supply window, grate bars, a heat exchanger located above the combustion chamber. The heat exchanger is made in the form of a horizontally located stepped channel of rectangular section, the steps of which are arranged in one row, while a pair of short sides of the rectangular section of the channel is located horizontally, a pair of long sides of the rectangular section of the channel is located vertically, and the front end wall of the heat exchanger is equipped with a hatch, access to which is provided through the loading door.

Particular options for implementing the utility model:

solid fuel boiler of long burning, in which the heat exchanger is made in the form of a two-, four- or six-stage channel;

solid fuel boiler of long burning, in which the grate is made hollow, and their cavities are connected to the coolant tank;

the solid propellant copper of long burning contains the fan;

solid fuel boiler of long burning contains air ducts and nozzles;

solid fuel boiler of long burning, in which the nozzles are located at an angle to the walls of the body;

solid fuel boiler of long burning contains an ash chamber;

solid fuel boiler of long burning, in which the front end wall of the heat exchanger is made at an angle to the horizontal;

solid fuel boiler of long burning, which contains at least one additional hatch.

The essence of the utility model is disclosed in the drawings and in the description.

Fig. 1 - Front view of a solid fuel boiler for long burning.

Fig. 2 - Side view of a solid fuel boiler for long burning.

Fig. 3 - Vertical section of the body of a long-burning solid fuel boiler.

Fig. 4 - Vertical section of the body of a long-burning solid fuel boiler.

Fig. 5 - Horizontal section of the heat exchanger.

In FIG. 1 shows a front view, and figure 2 is a side view of a long-burning solid fuel boiler, which contains a body (1), a fan (2), air ducts (3), a chimney outlet (4), a loading door (5), an unloading door (6), ash pan door (7).

In FIG. 3 shows a vertical section A-A of a long-burning solid fuel boiler, which contains nozzles (9), an air supply window (10), grates (11), a heat exchanger (12) located above the combustion chamber (13), and an ash chamber (14 ). The heat exchanger (12), as well as the housing (1), is made with double walls forming a heat carrier tank. The capacity of the coolant in the housing and in the heat exchanger is shown in the figures by hatching. Due to the location of the heat exchanger (12) above the combustion chamber (13), more uniform and faster heating of the heat exchanger (12) is provided. The grate (11) can be made in the form of hollow structures and connected to the heat carrier tank, which will increase the heat exchange area and increase the efficiency of the boiler. The end wall (17) of the heat exchanger (12) is inclined to the horizontal plane and is equipped with two hatches (18). This arrangement will reduce the number of doors on the body (1) of a long-burning solid fuel boiler to three, which will accordingly increase the usable heat exchange area, reduce heat loss and reduce labor costs for installing doors on the boiler body. The loading door (5), in addition to filling the combustion chamber (13) with solid fuel, is designed to provide access for maintenance and cleaning of the heat exchanger channel (12).

The nozzles (9) are connected to the air ducts (3) and provide air to the combustion chamber (13), while they are installed at an angle of 45 degrees to the walls of the housing (1) and directed downwards. Such an inclination of the nozzles (9) is necessary in order to supply air directly to the combustion zone of solid fuel, since during combustion the volume of fuel in the combustion chamber (13) gradually decreases.

In FIG. 4 shows a vertical section B-B of the body (1) of a long-burning solid fuel boiler, which shows a heat exchanger (12) made in the form of a four-stage channel. Each channel stage in vertical section forms a rectangle, which contains a pair of short sides (15) located horizontally and a pair of long sides (16) located vertically. With this shape and location of the channel, the degree of clogging of the heat exchanger (12) is significantly reduced, since a significant part of the combustion products entering the heat exchanger (12) from the combustion chamber (13) due to the greater height of particle settling, in comparison with the prototype, does not have time to settle to the bottom channel and flies out. In this case, the remaining part of the combustion products will settle on a much smaller area forming the bottom of the heat exchanger channel (12) and, accordingly, the clogging surface will be much smaller than that of the prototype, which will lead to a slight decrease in heat transfer.

As a result of testing prototypes, the recommended aspect ratio of the cross section of the heat exchanger channel (12) was determined. The length of the vertical side of the rectangular section of the duct must be at least twice the length of the horizontal side of the duct section.

In FIG. 5, a horizontal section B-B of the heat exchanger (12) shows the path of the flue gases in the channel of the heat exchanger (12). The heated flue gases enter the stepped channel of the heat exchanger (12) directly from the combustion chamber (13) through the inlet, the heat exchanger stages (12) pass through the horizontal “snake”, where they release thermal energy to the coolant and exit through the outlet pipe of the chimney (4) to the outside.

Solid fuel boiler long burning works as follows.

Through the loading door (5) in the combustion chamber (13) on the grate (11) place solid fuel, such as firewood or coal, set it on fire from above and close the loading door (5). On the controller (not shown), the required coolant temperature is set and the boiler is started. To distribute and supply air through the combustion chamber (13) and the ash chamber (14), air ducts (3) are mounted on the body (1). The controller controls the operation of the fan (2), which supplies air through the air supply window (10) to the ash chamber (14), while the main part of the air passes from the bottom up through the grate (11) through the entire volume of the loaded fuel. To ensure more efficient fuel combustion, an additional part of the air is supplied to the combustion chamber (13) through nozzles (9) located at an angle of 45 degrees to the burning fuel layer. The process of air supply occurs until the temperature of the coolant reaches the temperature set on the controller. As soon as the temperature reaches the temperature set on the controller, the fan turns off and the boiler enters the smoldering mode. After the temperature drops below the one set on the controller, the fan turns on again and pumps the required amount of air into the combustion chamber (13), which contributes to fuel ignition and temperature increase. Thus, the process is repeated as long as there is fuel in the combustion chamber (13). The flue gases emitted during the combustion process transfer thermal energy to the coolant circulating between the double walls of the housing (1), for example, water. Further, flue gases from the combustion chamber (13) enter the stepped channel of the heat exchanger (12), go around its walls, transferring thermal energy to the coolant through them. At the same time, most of the combustion products, due to the developed design of the heat exchanger (12), made in the form of a horizontally located stepped channel of rectangular cross section, the large sides (16) of which are placed vertically and form the height of the channel, do not settle at the bottom of the heat exchanger (12), but fly out together with the cooled flue gases out through the chimney outlet (4). The boiler is cleaned through the discharge door (6), and small combustion products, such as ash, are removed from the boiler through the ash pan doors (7). If necessary, the heat exchanger channel (12) can be cleaned through open hatches (18), access to which is provided through the loading door (5).

Claims (5)

1. Solid fuel long-burning boiler, containing a body (1) with double walls forming a coolant tank, a fan (2), air ducts (3), a chimney outlet (4), a loading door (5), an unloading door (6), ash pan door (7), nozzles (9), air supply window (10), grates (11), heat exchanger (12) located above the combustion chamber (13), and ash chamber (14), characterized in that the heat exchanger (12 ) is made in the form of a horizontally located stepped channel of rectangular section, the steps of which are arranged in one row, while a pair of short sides (15) of a rectangular section of the channel is located horizontally, a pair of long sides (16) of a rectangular section of the channel is located vertically, and the front end wall (17 ) of the heat exchanger (12) is made at an angle to the horizontal and equipped with a hatch (18), access to which is provided through the loading door (5). 2. Solid fuel long-burning boiler according to claim 1, characterized in that the heat exchanger (12) is made in the form of a two-, four- or six-stage channel. 3. A solid fuel boiler of long burning according to claim 1, characterized in that the grate (11) is made hollow, and their cavities are connected to the coolant tank. 4. Solid fuel long-burning boiler according to claim 1, characterized in that the nozzles (9) are located at an angle to the walls of the housing (1). 5. Solid fuel boiler of long burning according to claim 1, characterized in that it contains at least one additional hatch (18).

Images