Tubular Boiler with Incorporated Oven

Abstract

The invention relates to a tubular boiler with a heat exchange tube with at least one helical layer situated in a heat exchange chamber, and which includes a set of laterally joined spirals. The boiler includes, an inner side of the helical layer, an oven that is rigidly joined to said layer and connected to a feeder by means of which fuel is supplied. The boiler also includes an output collector for collecting ash and slag, which connects the inside of the heat exchange chamber to the outside of the boiler, and a forced-air-current generator that generates a movement of air inside the boiler and directs it to the oven. This movement of air moves the ash and slag along the at least one helical layer to the output collector.

Claims

1. A tubular heat exchange boiler comprising: a heat exchange tube having a distribution comprising at least one helical layer; wherein said layer comprises a set of laterally joined spirals, said layer being situated in a heat exchange chamber of the tubular boiler; wherein the boiler comprises on the inside thereof: an oven situated on an inner side of the helical layer of the heat exchange tube, said oven being rigidly joined to said layer and connected to a fuel feeder; the fuel feeder connected to the oven and configured for supplying fuel to be burned; an output collector for collecting ash and slag, which connects the inside of the heat exchange chamber to the outside of the boiler; and a forced-air-current generator, configured for generating a movement of air inside the boiler and directing it to the oven; wherein said movement of air moves the ash and slag along the at least one layer of the heat exchange tube to the output collector.

2. The tubular heat exchange boiler according to claim 1, wherein the feeder comprises: a feeder conduit which connects the outside of the tubular boiler to the feeder and is configured for introducing fuel into said feeder, from the outside of the boiler; a tank connected to the feeder conduit, where the fuel introduced by said feeder conduit is accumulated before being introduced into the oven; a mechanism configured for introducing the fuel accumulated in the tank into the oven; and a support configured for holding the fuel feeder inside the boiler.

3. The tubular heat exchange boiler according to claim 1, wherein the feeder conduit is situated above the tank of the fuel feeder, in the vertical position.

4. The tubular heat exchange boiler according to claim 2, wherein the mechanism configured for introducing the fuel accumulated in the tank into the oven comprises a motor configured for turning a worm screw.

5. The tubular heat exchange boiler according to claim 1, wherein the heat exchange tube has a distribution comprising two or more helical layers, wherein said layers are situated in a concentric and overlapping manner.

6. The tubular heat exchange boiler according to claim 1, wherein the spirals of each helical layer of the heat exchange tube present an inclination with respect to a height of said helical layer, with said inclinations alternating in each layer.

7. The tubular heat exchange boiler according to claim 1, wherein each helical layer of the heat exchange tube has a cylindrical shape.

8. The tubular heat exchange boiler according to claim 1, wherein each helical layer of the heat exchange tube has a conical shape, wherein each of the layers comprise alternating inverse tapering.

9. The tubular heat exchange boiler according to claim 1, wherein the oven comprises a cylindrical or conical outer shape, situated concentrically to the helical layers of the heat exchange tube, wherein a height of the cylindrical or conical outer shape of the oven is comprised between a quarter and two quarter parts of the height defining the helical layers of the heat exchange tube.

10. The tubular heat exchange boiler according to claim 1, wherein the oven comprises: conduits connecting an inner side of said oven with the current generator, the movement of air going through same; a fuel inlet connected to the fuel feeder; and at least one igniter situated in the conduits.

11. The tubular heat exchange boiler according to claim 9, wherein the fuel inlet is situated concentrically to the base of the cylindrical or conical outer shape of the oven.

12. The tubular heat exchange boiler according to claim 1, wherein the fuel burned in the boiler is biomass.

13. The tubular heat exchange boiler according to claim 1, wherein that the heat exchange chamber comprises a gas outlet conduit situated in an upper extreme position of the tubular boiler.

14. The tubular heat exchange boiler according to claim 1, wherein the feeder comprises a counterweight in a lower part of said feeder, and in that the support comprises at least two parallel shafts with at least two wheels, with one wheel at each end of said shafts, and two parallel rails configured for fitting with the wheels.

15. The tubular heat exchange boiler according to claim 1, wherein the boiler comprises a cylindrical shape, is horizontally positioned, wherein the heat exchange tube comprises an inlet and an outlet for a fluid into/out of the boiler, said inlet and said outlet being arranged on a longitudinal axis of said cylindrical shape of the boiler.

16. The tubular heat exchange boiler according to claim 15, wherein the rails of the support have a ring shape and are situated and rigidly joined inside the boiler, concentrically to the cylindrical shape of said boiler.

17. The tubular heat exchange boiler according to claim 15, wherein the boiler is configured for turning by means of a rotary movement about the longitudinal axis of the cylindrical shape of the boiler.

18. The tubular heat exchange boiler according claim 1, wherein the tubular heat exchange boiler comprises a rotor, situated on the outside of the boiler, configured for performing the rotary movement of the boiler.

19. The tubular heat exchange boiler according to claim 15, wherein the heat exchange tube comprises rotary joints at the inlet and at the outlet of said tube, on the outside of the boiler.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0051] To complete the description of the disclosure, and for the purpose of helping to make the features thereof more readily understandable, according to a preferred exemplary embodiment thereof, a drawing is included wherein, by way of illustration and not limitation, the following figure has been represented:

[0052] FIG. 1 depicts an elevational view of the tubular boiler which shows the heat exchange tube formed by two cylindrical and concentric layers, with the spirals joined, where the oven is located inside the innermost layer.

[0053] A list of the references used in the figures is provided below:

[0054] 1) Heat exchange tube

[0055] 11) Inlet

[0056] 12) Outlet

[0057] 101) Rotary movement

[0058] 102) Movement of air

[0059] 2) Output collector

[0060] 3) Oven

[0061] 31) Conduits

[0062] 32) Fuel inlet

[0063] 4) Feeder

[0064] 41) Motor

[0065] 42) Worm screw

[0066] 43) Tank

[0067] 44) Support

[0068] 45) Counterweight

[0069] 46) Feeder conduit

[0070] 5) Heat exchange chamber

[0071] 6) Current generator

[0072] 7) Igniter

[0073] 8) Gas outlet

DETAILED DESCRIPTION

[0074] The present disclosure relates to a horizontally oriented boiler, which uses as fuel biomass, which generates ash or slag during combustion, such that, after start-up thereof, it does not need to be stopped or intervened with for carrying out cleaning tasks.

[0075] As can be seen in FIG. 1, the boiler is made up of a cylindrical helical or cylindrical coil heat exchange tube (1), forming two concentric layers, with a small separation between them, which enables there to be a heat exchange surface of the entire conduit, by means of convection, superior to single-layer coils.

[0076] The spirals of said layers are joined together, without there being openings or a separation between same. Said heat exchange tube (1) is housed in a heat exchange chamber (5) of the boiler, said chamber (5) being cylindrical, like the boiler.

[0077] One of the advantages of the disclosure is that the oven (3) is situated inside the innermost helical layer of the heat exchange tube (1), being rigidly joined to same, said oven (3) having an outer cylindrical shape, having a conical internal hollow and covering half the length of the helical layer of the tube (1).

[0078] Therefore, the heat exchange between the oven (3) and the exchange tube (1) is direct, does not require an attached chamber for housing said oven (3) and has a higher efficiency that if it were in an attached chamber and heat exchange was performed only by the heating of the gases generated in the combustion.

[0079] The oven (3) is connected to a fuel feeder (4) also situated inside the boiler, in a space outside the heat exchange chamber (5). Said feeder (4) comprises a feeder conduit (46), situated in the vertical position, which allows the inlet of fuel from outside the boiler into a tank (43) of said feeder (4), where the fuel is stored before being introduced by means of a mechanism into the oven (3), through the fuel inlet (32). This mechanism is formed by a motor (41) turning a worm screw (42), which moves the fuel to the fuel inlet (32), said inlet (32) being a conduit situated in a concentric position at the cylindrical base of the oven (3). The feeder (4) thereby allows fuel to pass from the outside of the boiler into the oven (3).

[0080] The boiler also comprises a current generator (6) that generates a movement of air (102) inside the boiler, which moves to the inside of the oven (3) and goes through it by means of conduits (31). These conduits consist of openings made in said oven (3) and favor oxygen reaching same until the combustion of the oven (3), but they also help move the slag and ash generated in the combustion to an output collector (2) where such waste is extracted.

[0081] Moreover, the boiler has a gas outlet (8) situated at an upper end of said boiler, configured for extracting the gases generated during combustion, and a series of igniters (7) situated in the conduits (31) configured for starting the ignition of the fuel introduced in the oven (3).

[0082] When the boiler is in operation, slow rotary movement (101) is produced, rotating the entire boiler with respect to the shaft of the cylindrical shape of said boiler, such that the elements comprised on the inside thereof such as the heat exchange tube (1) and the oven (3) are turned, but not the feeder (4), the feeder conduit (46), the gas outlet (8) and the output collector (2), which remain immobile.

[0083] For the rotary movement (101) of the tube (1) not to collide with any of the elements needed for the operation of the boiler, both the outlet (12) and the inlet (11) are situated on the central axis of said cylindrical boiler. The feeder (4) comprises a support (44) which consists of an attachment that allows the movement of said feeder (4) with respect to the boiler as it comprises two shafts with wheels at the ends thereof fitted in rails with a ring shape.

[0084] Said rails are situated concentrically to the inner part of the boiler, in the attached space in which the feeder (4) is located, and are joined by means of a series of rigid attachments which allow the heat exchange tube (1) to turn around the feeder (4). That is, it is as if the rails were located on a sleeve or internal structure of a smaller size than the internal diameter of the boiler, and said internal structure was joined to the boiler in a rigid manner at several points of its perimeter, such that the heat exchange tube (1) is situated outside that internal structure, but inside the boiler.

[0085] For the feeder (4) to remain immobile while the boiler turns, it comprises a counterweight (45) which pulls the feeder downwards due to the effect of gravity and prevents the feeder (4) from being off-centre with respect to the oven (3).

[0086] The tube (1) is thereby heated from the combustion performed in the oven (3) and by the movement of hot air (102), under forced ventilation, flowing through the layers having a concentric section, increasing the temperature of the fluid circulating on the inside of said heat exchange tube (1).

[0087] The rotary movement (101) and the movement of hot air (102) under forced ventilation generate a movement of the ash and slag from combustion, moving them through the layers having a concentric section. This slag and ash are positioned on the internal portion of the coil and move over the external surface of the heat exchange tube (1), due to the rotary movement (101), operating as a worm screw, transforming this rotary movement into translation, to be extracted through the output collector (2).

[0088] The rotary movement (101) of the heat exchange tube (1) in addition to removing the ash and slag content from the boiler, further improves the heat exchange between the chamber and the fluid that circulates inside the heat exchange tube (1) by allowing the hot air to more easily reach all the cavities of the exchange chamber (5) and increase the movement of the fluid inside the tube (1).

[0089] The rotary movement (101) of the heat exchange tube (1) is generated by a rotor situated outside the boiler, so that it is not affected by the high temperatures generated inside.

[0090] To prevent liquid from leaking out, the heat exchange tube (1) has rotary joints both at the inlet (11) and at the outlet (12) of said tube (1) of the boiler, which allow the rotary movement at the same time as the inlet and outlet of the fluid to be heated, without fluid leaking out.

[0091] The movement of air (102) generated by the forced-current generator (6) is offset and favored by a forced-draft fan positioned at the gas outlet (8) of the heat exchange chamber (5). This fan sucks in the air from inside the exchange chamber (5), improving the entrance of the movement of air (102) into the oven and generating a forced ventilation.

[0092] The present disclosure should not be limited to the embodiment described herein. Other configurations may be carried out by those skilled in the art based on the present description. Accordingly, the scope of the disclosure is defined by the following claims.