FR2522114A1 - Boiler burning solid fuel - has heat exchanger and fuel loading chamber in column - Google Patents

Abstract

The boiler burns wood or other solid fuel, having a grate at the bottom of the combustion chamber for ash discharge and supply of fresh air, a fuel-loading hatch at the chamber top, and a tubular heat exchanger. The chamber (13) into which the fuel is loaded and the heat exchanger (14) are in column form, the former discharging into the top of the combustion chamber (12) and being closed at the sides and top. The heat exchanger column has one or more flues (21a) between the combustion chamber and the main flue (29), and a fresh air supply passage (39) discharges into the top of the combustion chamber at the side of the fuel-loading chamber nearest to the heat-exchanger column.

Description

"Wood boiler or other solid combustible material"
The present invention relates to a boiler with wood or other solid combustible materials intended to heat a fluid such as water so as to form, for example, a central heating boiler.

 There are currently known a large number of central heating boilers capable of burning solid fuels.

However, most known boilers can only function properly if the fuel is completely dry before being introduced into the boiler. Furthermore, current boilers do not have a structure allowing them to burn the gases from the combustion of solid material almost completely.

 The object of the present invention is in particular to remedy the drawbacks of the prior art and provides a wood-fired boiler or other solid combustible material, the structure of which enables any solid combustible material to be burned, as well as almost all combustible gases. products, while producing a large amount of heat for low fuel consumption.

 The wood boiler or other solid combustible material according to the present invention, in which a fluid such as water circulates in order to heat it, comprises a combustion chamber provided at its lower part with a grid for the evacuation ash and the supply of fresh air into this combustion chamber, a solid fuel receiving chamber provided at its upper part with an access door for charging the fuel and at least one tubular heat exchanger in which circulates said fluid and the hot fumes or gases.

According to the present invention, said receiving chamber and said heat exchanger are in the form of columns, the column forming the receiving chamber opening from above into said combustion chamber and being closed laterally and above, the column forming said heat exchanger having at least a smoke evacuation channel, one end of which opens out from above into said combustion chamber and the other end of which is connected to the flue outlet duct, at least one supply duct fresh air emerging in the upper part of said combustion chamber laterally to said
solid fuel receiving column on the side
of said column forming a heat exchanger.

The boiler according to the present invention comprises,
preferably, at least one conduit connecting the upper part of
said column forming a solid fuel receiving chamber and
the combustion chamber, this duct opening into the upper part
of this combustion chamber laterally to said column
forming receiving chamber and on the side of said column forming
heat exchanger.

As the solid fuel is partly in the cham
combustion flue and largely in the chamber column
receiving fuel closed laterally and above, the column
forming the fuel receiving chamber works exactly as
a gasifier and the lean gases produced are burnt in the upper part
combustion chamber thanks to the fresh air introduced into
this chamber via said air supply duct. I1 therefore occurs
solid fuel combustion in gas production
poor and a combustion of these poor gases.

 According to the present invention, said column forming receiving chamber comprises, in its upper part, a door that can be actuated from the outside and capable of bringing said column into communication with the flue outlet duct.

 The boiler according to the present invention preferably comprises an upper chamber into which opens the end of said smoke evacuation channel and from which leaves said smoke outlet duct, said door making it possible to put said column in communication forming solid fuel receiving chamber and this upper chamber.

 According to the present invention, said column forming a chamber for receiving solid fuel and said column forming an exchanger are preferably adjacent and vertical.

 According to the present invention, the boiler preferably comprises an aquastat subjected to the temperature of said fluid and having a lever capable of actuating a control flap for the supply of fresh air into said combustion chamber through said grate. .

According to the present invention, said fresh air supply duct in the upper part of the combustion chamber
can advantageously be fitted with a suspended adjustment flap of which
the opening depends on the air flow in this duct to bring fresh air.

According to the present invention, this air supply duct
cool can advantageously extend into said combustion chamber
and preferably has radial outlet openings.

The present invention will be better understood on study
a wood boiler or other solid combustible material described
by way of nonlimiting example and illustrated schematically by the
drawing on which
- the. Figure 1 shows a vertical longitudinal section of the boiler
- Figure 2 shows a cross section along II-II of the boiler shown in Figure I
and FIG. 3 represents a horizontal section along III-III of the boiler shown in FIG. 1.

 The boiler shown in the figures and generally identified by the reference 7 is in the form of a rectangular parallelepiped delimited externally by a parallelepipedal box generally identified by the reference 2 and comprising two longitudinal and vertical walls 3 and 4, two transverse and vertical walls 5 and 6, a lower horizontal wall 7 and an upper horizontal wall 8.

 In its lower part, the boiler 1 has a compartment 9 delimited in its lower part by the lower wall 7 and in its upper part by a horizontal partition 10.

In this compartment 9 can be disposed an ashtray 11 introduced by an opening made in the lower part of the transverse wall 5 of the box 2.

 In the interior of the box 2, between the horizontal partition 10 and the horizontal upper wall 8, the boiler 1 has a combustion chamber 12 and, above this combustion chamber 12, a vertical hollow column 13 and a column vertical 14 forming a heat exchanger.

 The horizontal partition 10 has a central opening 15 below which is disposed, in the compartment 9, a grid 16 capable of being moved horizontally for cleaning by means of a lever system 17 extending outside .

 As can be seen in FIG. 3, the column 13 forms a vertical chamber which opens out from above into the combustion chamber J2 and which is delimited, inside the box 2, by a transverse and vertical wall 18a located at a distance from the side wall 5 of the box 2, by a transverse and vertical wall 18 located substantially in the middle of the box 2 and by two longitudinal and vertical walls 19 and 20 which are respectively at a distance from the longitudinal walls 3 and 4 of the box 2 and which join the walls transverse 18.and 18a.

 Go it can be seen in Figures 3 and 2, the walls 18a, 19 and 20 of the vertical chamber 13 extend down from the upper horizontal wall 8 of the box 2 and are extended down to to the horizontal partition 10 so as to form a transverse wall and the longitudinal walls of the combustion chamber 12. The transverse wall 18 of the chamber 13 extends downwards from the horizontal upper wall 8 of the box 2 up to above the combustion chamber 12, so that its lower edge is at a distance from the horizontal partition 10.

 Flowing, it can be seen in particular in FIG. 3, the column forming a tubular heat exchanger 14 is formed by twelve vertical tubes 21 of square section located at equal distance from each other and from the walls 3, 4 and 6 of the box 2 and of the transverse wall 18 of the vertical chamber 13.

 As can be seen in FIG. 1, the upper end of the tubes 21 is located at a distance from the upper horizontal wall 8 of the box 2 and are joined by a plate 22 which extends between the tubes 21 so that the the interior of the tubes 21 opens upwards into an upper chamber 23 having the walls 3, 4 and 6 of the box 2 as vertical walls and the partition 18 of the vertical chamber 13 and as the upper wall the upper horizontal wall 8 of the box 2.

 Likewise, the lower ends of the tubes 21 are connected by a horizontal plate 24 so that the interior of the tubes 21 opens from above into the combustion chamber 12, the tubes 21 forming vertical evacuation channels connecting the combustion chamber 12 and the upper chamber 23.

 The transverse wall 18 of the chamber 13 is extended downwardly inclined below the column 14 by a portion 18.b, a wall 25 being arranged transversely and parallel to the extension 18b so that the space located between the tubes 21 adjacent to the wall 18 extend between the extension 18b and the transverse wall 25 and is closed at its lower end.

 On the side opposite its transverse wall 18a, the combustion chamber 12 has a transverse wall 26 which is located at a distance from the vertical wall 6 of the box 2. This transverse wall 26 extends between the exchanger column 14 and the horizontal partition 10 and on the other hand between the longitudinal walls 19 and 20 of the combustion chamber 12.

 It appears from the above that the spaces delimited by the box 2, the vertical walls of the combustion chamber 12 and the vertical chamber 13 and the tubes 21 are closed and sealed and can advantageously be traversed by a fluid such as l 'water, the boiler 1 being double partitions. For this purpose, there is provided laterally, in the lower part of the box 2, a water inlet pipe 27 and in the upper part of the exchanger column 14 a water outlet pipe 28, the circulation of the water can be provided by a pump not shown.

 As can be seen in the figure], a smoke outlet duct 29 is connected to the upper chamber 23 and passes through the upper horizontal wall 8 of the box 2.

 In its upper part, the transverse partition 18 of the vertical chamber 13 has an opening 30 for communication with the upper chamber 23. A door 31 operable from the outside by a lever 32 makes it possible to close or open this opening of com- munication 30.

 In the upper part of the chamber 13, the boiler 1 has a loading door 33 which closes an opening 34 made in the double wall 5, 18a. The boiler 1 also has, in its lower part, inspection doors 35 and 36 giving access to the combustion chamber 12.

 Inside the chamber 13 and on the side of its transverse wall 18, two vertical conduits 37 and 38 are provided, the upper ends of which open into the upper part of the vertical chamber 13 and the lower ends of which open into the upper part of the combustion chamber 12, their ends having been bevelled.

 As can be seen in particular in FIG. 2, the boiler 1 has a transverse duct 39 for supplying outside air which extends in the upper part of the combustion chamber 12 below the column forming the heat exchanger. heat 14 and which has radial air outlet orifices 40 oriented substantially in the zone situated at the lower ends of the vertical ducts 37 and 38. The air supply duct 39 passes through the double wall 3, 19 and has, at its open outer end, an adjustment flap 41 suspended around a horizontal axis 42 offset upwards, the opening of this flap 41 depending on the air flow in the duct 39.

 the compartment 9 has, in the wall 6 of the sound box: 2, an external opening 43 provided for the supply of air into the combustion chamber 12 through the grate 16 This opening can be closed by a flap 44 articulated in its upper part around a horizontal axis 45. The door 44 carries an arm 46 the end of which is connected to the end of the lever 47 of an aquastat 48 by means of a chain 49, the aquastat 48 being mounted on the water outlet duct 28, so as to automatically control the opening and closing of the flap 44 as a function of the temperature leaving the boiler 1.

 Around its lower opening 15, the combustion chamber 12 is lined with a refractory material 50, the inner wall of which is inclined in the direction of the opening 15. The box 2 is lined externally with an insulator 51, for example glass wool and doors 33, 35 and 36 are lined internally with asbestos.

 We will now describe how the boiler just described works and how it can be used, assuming that there is in the combustion chamber 12 a residue of wood and charcoal burning.

 If one wishes to load the boiler 7 with wood or any other solid combustible material, care is first taken to open the door 31 so as to put the vertical chamber 13 in communication with the smoke outlet duct 29 via the upper chamber 23. The loading door 33 is opened. As the door 31 is open, the fumes or flames tend to go towards the upper chamber 23 and towards the smoke duct 29 and do not exit accordingly not through the access opening 34. The wood is introduced through the opening 34. The wood falls and gradually fills the combustion chamber 12 at least in the area below the vertical chamber 13 and the vertical chamber or column 13.

When the vertical chamber 13 is full, the door 33 is closed and the communication door 31 is closed.

 Thanks to the air introduced into the combustion chamber 12 through the grate 16, the combustion of the wood takes place, the quantity of air admitted being regulated by means of the flap 44 which is controlled by the aquastat 48, in order to keep the temperature of the water leaving substantially constant.

 During the combustion of wood in the combustion chamber 12, gases are produced which are released in the upper part of the combustion chamber] 2 and which bridge in the vertical chamber 13 which behaves like a gasifier, Like the chamber vertical 33 is closed in its entire upper part, the gases produced descend by passing through the vertical conduits 37 and 38 to find themselves in the upper part of the combustion chamber 12 below the column forming a heat exchanger 14.

Thanks to the fresh air introduced into the upper part of the combustion chamber 12 through the transverse duct 13, the combustion gases produced burn almost completely.

 All the fumes from the combustions are then evacuated by the vertical channels 21a delimited by the tubes 21 of the column forming the heat exchanger 14, the upper chamber 23 and the smoke outlet duct 29.

 Thanks to the suspended flap 41, the quantity of air admitted into the combustion chamber 12 through the duct 39 is automatically regulated as a function of the flow of gas produced.

 The present invention is not limited to the example described above. One could have built in particular the means intended to convey the fresh air and the means intended for the transport of combustion gases in a different way. Instead of being substantially rectangular sections, the columns 13 and 14 and the vertical tubes 21 could have been of different shapes such as for example circular.

Claims (8)

 1, a wood-fired boiler or other solid combustible material, in which a fluid such as water circulates in order to heat it, comprising a combustion chamber provided at its lower part with a grid for the evacuation of the ashes and the supply of fresh air into the combustion chamber, a solid fuel receiving chamber provided at its upper part with an access door for charging the fuel, and at least one tubular heat exchanger in which said fluid circulates and fumes and hot gases, characterized in that said receiving chamber (13) and said heat exchanger (14) are present in the column fort, the column forming the receiving chamber of solid fuel emerging from above into said combustion chamber (12) and being closed laterally and above, the column forming the heat exchanger having at least one smoke evacuation channel (21a) one end of which opens out from above into the said combustion chamber (12) and the other end of which is connected to the flue outlet duct (29), with care a fresh air supply duct (39) opening into the upper part of the combustion chamber ( 12) laterally to said column forming a solid fuel receiving chamber (13) on the side of the column forming said heat exchanger (14).  2. Boiler according to claim 1, characterized in that it comprises at the ends a conduit (37, 38) connecting the upper part of said column forming the solid fuel receiving chamber (13) and the combustion chamber (12) , this duct opening into the upper part of this combustion chamber laterally to said column forming said solid fuel receiving chamber and on the side of said column forming heat exchanger.  3. Boiler according to one of claims 1 and 2, characterized in that said column forming the solid fuel receiving chamber (13) comprises in its upper part a door (31) operable from the outside and capable of communication this column (13) with the smoke outlet pipe (29).  4. Boiler according to claim 3, characterized in that it comprises an upper chamber (23) into which opens the end of said smoke evacuation channel (21a) and from which leaves said smoke outlet duct (29 ), said door (31) allowing the column forming the solid fuel receiving chamber (13) to be placed in communication with this upper chamber (23).  5. Boiler according to any one of the preceding claims, characterized in that the column forming the solid fuel receiving chamber (13) and the column forming the heat exchanger (74) are adjacent and vertical.  6. Boiler according to any one of the preceding claims, characterized in that it comprises an aquastat (48) subjected to the temperature of said fluid and having a lever (47) capable of actuating an adjustment flap (44) of the supply of fresh air into the combustion chamber (12) through said grid (16).  7. Boiler according to any one of the preceding claims, characterized in that said fresh air supply duct (39) to said combustion chamber (72) is provided with an adjustable valet (43) suspended whose opening depends on the air flow in this duct.  8. Boiler according to any one of the preceding claims, characterized in that said fresh air supply duct (39) extends in said combustion chamber (12) and has radial outlet orifices (40) .