CHIMNEY STARTER AND CATALYST UNIT FOR A CHIMNEY STARTER

Abstract

An ignition chimney (1) for carbonaceous fuel (2) is shown and described, with a housing (3), a lower combustion chamber (4) formed in the housing (3) for easily ignitable igniter (5), with an upper combustion chamber (6) formed in the housing (3) for the carbonaceous fuel (2), wherein, in the ready-for-operation state, the upper combustion chamber (6) is arranged above the lower combustion chamber (4), and the lower combustion chamber (4) and the upper combustion chamber (6) are separated from one another by a gas-permeable separator (7), the upper side (8) of the separator (7), which faces the upper combustion chamber (6), forming a receptacle for the fuel (2), the separator (7) being designed such that the igniter exhaust gases (9) produced in the ignited state of the igniter (5) pass through the separator (7) and impinge on the fuel (2) resting on the separator (7).

The risk of carbon monoxide poisoning by exhaust gases during combustion of the (carbonaceous) fuel is considerably reduced in the ignition chimney in that a catalyst (11) for catalyzing the oxidation of carbon monoxide to carbon dioxide with oxygen is arranged above the receptacle for the fuel (2) in such a way, that the fuel exhaust gases (12) produced in the ignited state of the fuel (2) are at least partially conducted to the catalyst (11) or through the catalyst (11) and at least part of the carbon monoxide present in the fuel exhaust gases (12) is oxidized to carbon dioxide.

Claims

1. Ignition chimney (1) for carbonaceous fuel (2), with a housing (3), a lower combustion chamber (4) formed in the housing (3) for easily ignitable igniter (5), with an upper combustion chamber (6) formed in the housing (3) for the carbonaceous fuel (2), wherein, in the ready-for-operation state, the upper combustion chamber (6) is arranged above the lower combustion chamber (4), and the lower combustion chamber (4) and the upper combustion chamber (6) are separated from one another by a gas-permeable separator (7), wherein the upper side (8) of the separator (7), which faces the upper combustion chamber (6), forms a receptacle for the fuel (2), wherein the separator (7) is designed in such a way that the igniter exhaust gases (9) produced in the ignited state of the igniter (5) pass through the separator (7) and strike the fuel (2) resting on the separator (7), characterized in that a catalyst (11) for catalyzing the oxidation of carbon monoxide to carbon dioxide with oxygen is arranged above the receptacle for the fuel (2) in such a way that the fuel exhaust gases (12) produced in the ignited state of the fuel (2) are directed at least partially to the catalyst (11) or through the catalyst (11) and at least some of the carbon monoxide present in the fuel exhaust gases (12) is oxidized to carbon dioxide.

2. Ignition chimney (1) according to claim 1, characterized in that the catalyst (11) is arranged or designed in such a way that, in the operating state, when the fuel (2) is ignited, the oxygen required to catalyze the oxidation of carbon monoxide to carbon dioxide is provided by ambient air (13).

3. Ignition chimney (1) according to claim 1 or 2, characterized in that the catalyst (11) can be flowed through, wherein, in the intended operating state, where ignited fuel (2) and catalyst (11) are flowed through by the fuel exhaust gases (12), the catalyst (11) has such a low flow resistance between the inflow side (14) and the outflow side (15), that a pressure drop of at most 15 Pa, preferably of at most 1 Pa, preferably of at most 0.5 Pa, particularly preferably of at most 0.05 Pa, occurs.

4. Ignition chimney (1) according to any one of claims 1 to 3, characterized in that the catalyst (11) is designed such that the energy released by the ignited fuel (2) is sufficient to drive the fuel exhaust gases (12) through the catalyst (11).

5. Ignition chimney (1) according to any one of claims 1 to 4, characterized in that the catalyst (11) is formed at least partially from a coated, open-pored ceramic foam, wherein the coating is formed at least partially from metal oxides, in particular from transition metals and/or noble metals.

6. Ignition chimney (1) according to any one of claims 1 to 5, characterized in that the catalyst (11) is arranged relative to the receptacle for the fuel (2) in such a way that, in the operating state with ignited fuel (2), the energy transported by the ignited fuel (2) to the catalyst (11) is sufficient to achieve the catalyst temperature required for bringing about catalysis of carbon monoxide to carbon dioxide.

7. Ignition chimney (1) according to claim 6, characterized in that the catalyst (11) has a required catalyst temperature of at most 800° C., in particular of at most 400° C., in particular of at most 300° C., in particular of at most 200° C., preferably of at most 100° C.

8. Ignition chimney (1) according to any one of claims 1 to 7, characterized in that a holder (16) for the catalyst (11) is formed in or on the housing (3), in particular in the upper region of the upper combustion chamber (6), wherein the catalyst (11) is held by the holder (16), in particular is held detachably by the holder (16).

9. Ignition chimney (1) according to any one of claims 1 to 8, characterized in that an opening (18) is formed in the housing (3) in the side region of the upper combustion chamber (6), via which opening the fuel (2) can be introduced into the upper combustion chamber (6) and can be removed from the upper combustion chamber (6), in particular without first removing the catalyst (11), in particular wherein it is possible to close the opening (18) with a closure element (19).

10. Ignition chimney (1) according to any one of claims 1 to 7, characterized in that the catalyst (11) is a component of a catalyst unit (20) with a tube (21) and the catalyst (11) is held in the tube (21), wherein the tube (21) extends between a first tube opening (22) and a second tube opening (23), wherein, in the assembled state of the catalyst unit (20), the first tube opening (22) is arranged below the second tube opening (23), wherein the catalyst (11) is held in the cross section of the tube (21) with a holding device (24) between the first tube opening (22) and the second tube opening (23), wherein, in order to achieve the assembled state of the catalyst unit (20), the tube (21) is inserted into the housing (3) in the region of the upper combustion chamber (6) or is slipped over the housing (3).

11. Ignition chimney (1) according to claim 10, characterized in that the catalyst (11) occupies at least 99%, preferably at least 95%, in particular at least 85%, preferably at least 75% of the cross-section of the tube (21).

12. Ignition chimney (1) according to claim 10 or 11, characterized in that the holding device (24) of the catalyst unit (20) in the tube (21) is designed as an at least partially circumferential collar, in particular wherein the collar has interruptions on which the catalyst (11) is supported in the assembled state due to its weight force.

13. Catalyst unit (20) for an ignition chimney (1) for carbonaceous fuel (2) with a catalyst (11) for catalyzing the oxidation of carbon monoxide to carbon dioxide with oxygen, wherein the ignition chimney (1) has a housing (3), a lower combustion chamber (4) formed in the housing (3) for easily ignitable igniter (5), an upper combustion chamber (6) formed in the housing (3) for the carbonaceous fuel (2), wherein, in the ready-for-operation state, the upper combustion chamber (6) is arranged above the lower combustion chamber (4) and the lower combustion chamber (4) is separated from the upper combustion chamber (6) by a gas-permeable separator (7), wherein the upper side (8) of the separator (7), which faces the upper combustion chamber (6), forms a receptacle for the fuel (2), wherein the separator (7) is formed in such a manner that the igniter exhaust gases (9) produced in the ignited state of the igniter (5) pass through the separator (7) and strike the fuel (2) resting on the separator (7), wherein the catalyst unit (20) comprises the catalyst (11) and a tube (21) and the catalyst (11) is held in the tube (21), wherein the tube (21) extends between a first tube opening (22) and a second tube opening (23) wherein, in the mounting state of the catalyst unit (20), the first tube opening (22) is located below the second tube opening (23), wherein the catalyst (11) is held in the cross-section of the tube (21) with a holding device (24) between the first tube opening (22) and the second tube opening (23), wherein, in order to achieve the assembled state of the catalyst unit (11), the tube (21) can be inserted into the housing (3) in the region of the upper combustion chamber (6) or can be slipped over the housing (3).

14. Catalyst unit (20) according to claim 13, characterized by the features of at least one characterizing portion of claims 1 to 12.

Description

[0024] In detail, there is now a plurality of possibilities for designing and further developing the ignition chimney according to the invention and the catalyst unit according to the invention. For this, reference is made both to the patent claims subordinate to the independent claims and to the following description of preferred embodiments in conjunction with the drawing. The drawing shows

[0025] FIG. 1 schematically, an ignition chimney with catalyst unit,

[0026] FIG. 2 an ignition chimney with a side opening in the housing in the upper combustion chamber and with a catalyst unit, and

[0027] FIG. 3 schematically, a catalyst unit with a housing, which is only partially indicated, of an ignition chimney.

[0028] In each of FIGS. 1 and 2, a complete ignition chimney 1 is shown. The ignition chimney 1 serves for the simple ignition of carbonaceous fuel 2. The ignition chimney 1 has a housing 3, a lower combustion chamber 4 formed in the housing 3 for easily ignitable igniters 5 and an upper combustion chamber 6 formed in the housing 3 for the carbonaceous fuel 2. The carbonaceous fuel 2 is charcoal such as are suitable for the operation of a grill or also for the operation of a water pipe. In the ready-to-use state, the upper combustion chamber 6 is arranged above the lower combustion chamber 4, and the lower combustion chamber 4 and the upper combustion chamber 6 are separated from each other by a gas-permeable separator 7. In the present case, the gas-permeable separator 7 is a perforated sheet. The upper side 8 of the separator 7, which faces the upper combustion chamber 6, forms a receptacle for the fuel 2. The separator 7 is designed in such a way that the igniter exhaust gases 9 produced in the ignited state of the igniter 5 pass through the separator 7 and strike the fuel 2 resting on the separator 7.

[0029] FIG. 2 shows an alternative to a flammable igniter 5. Here, an electric heating element 10 provides the heat required to ignite the fuel 2 in the upper combustion chamber 3. An electrical connection element 27 is provided on the housing 3 of the ignition chimney 1 for connecting the electrical heating element 10 to an electrical power source. Thus, the lower combustion chamber 4 does not necessarily have to accommodate a igniter 5, it can be any suitable heat source.

[0030] A handle 25 with a heat shield 26 is provided on the side of the housing for handling the ignition chimney 1.

[0031] Above the receptacle for the fuel 2, a catalyst 11 is provided for catalyzing the oxidation of carbon monoxide to carbon dioxide with oxygen. Accordingly, the catalyst 11 is arranged such that the fuel exhaust gases 12 produced when the fuel 2 is ignited are at least partially directed to the catalyst 11 or through the catalyst 11 and at least a portion of the carbon monoxide present in the fuel exhaust gases 12 is oxidized to carbon dioxide.

[0032] Carbon monoxide gas is formed during the primarily incomplete combustion of the carbonaceous fuel 2. Carbon monoxide is toxic to humans and causes asphyxiation above a certain breathing air concentration. The carbon monoxide is primarily a component of the fuel exhaust gas 12 produced when the fuel 2 is ignited. The emission of carbon monoxide is a massive problem, especially when ignition chimneys 1 are operated in enclosed spaces. It is not uncommon for inadmissible concentrations of carbon monoxide to be reached here, because insufficient provision has been made for adequate ventilation of the premises.

[0033] To solve this problem, a catalyst 11 is arranged above the receptacle for the fuel 2—and thus above the fuel 2. The catalyst 11 serves to catalyze the oxidation of carbon monoxide to carbon dioxide with oxygen. The catalyst 11 is arranged such that the fuel exhaust gases 12 produced in the ignited state of the fuel 2 are at least partially passed through the catalyst 11, and at least a portion of the carbon monoxide present in the fuel exhaust gases 12 is oxidized to carbon dioxide. In the following, therefore, the embodiment of the catalyst 11 or also of a separate catalyst unit 20, which is shown in FIG. 3 is essentially of concern.

[0034] Common to all embodiments is that the catalyst 11 is arranged or configured in such a way that, in the operating state, i.e. when the fuel 2 is ignited, the oxygen required for catalyzing the oxidation of carbon monoxide to carbon dioxide is provided by the ambient air 13. As a result, a separate oxygen supply for the catalyst 11 can be dispensed with, and the catalyst 11 is thus operable independently of a separate oxygen supply. For this, design measures are taken in part, which will be described further below. In the figures, the flow paths of ambient air 13 are partially indicated.

[0035] In all embodiments, the catalyst 11 can be flowed through by a gas, wherein, in the intended operating state with ignited fuel 2 and catalyst 11 flowed through by the fuel exhaust gases 12, the catalyst 11 has a very low flow resistance between the inflow side 14 and the outflow side 15. The flow resistance is set here such that, in the operating state and in flow equilibrium, at most a pressure difference of at most 0.5 Pa occurs between the inflow side 14 and the outflow side 15 of the catalyst 11.

[0036] All the embodiments shown also have in common that the catalyst 11 is designed in such a way that (under relatively normal ambient conditions) the energy released by the ignited fuel 2 is sufficient to drive the fuel exhaust gases 12 through the catalyst 11. This measure also recognizably contributes the catalyst 11 being able to be operated in a self-sufficient manner.

[0037] In the illustrated embodiments, the catalyst 11 is formed from a coated, open-pored ceramic foam. To achieve the catalytic effect, the ceramic foam is coated with metal oxides, in this case transition metals and noble metals. In the illustrated embodiments, the catalyst 11 is arranged relative to the receptacle for the fuel 2, and thus also relative to the fuel 2 itself, in such a way that, in the operating state when the fuel 2 is ignited or when the electric heating device 10 is active, the energy transported to the catalyst 11 by the ignited fuel 2 or the energy transported to the catalyst 11 by the electric heating device 10 is sufficient to achieve the catalyst temperature required for the catalysis of carbon monoxide to carbon dioxide to be effected. In the illustrated embodiments, the catalyst 11 has a required catalyst temperature of 350° C. However, experiments have shown that the catalytic effect promotes the oxidation of carbon monoxide with atmospheric oxygen to carbon dioxide even at considerably lower temperatures starting above 150° C.

[0038] As a result, the catalyst 11 shown in the figures can be operated completely autonomously. The supply of separate oxygen is not required (the atmospheric oxygen present in the ambient air 13 is sufficient), the catalyst 11 does not need to be force-ventilated (the convective air flow or flow of fuel exhaust gases 12 caused by the combustion of the fuel 2 is sufficient), and the catalyst 11 used does not require any energy supply other than that which it receives anyway due to its arrangement above the ignited fuel 2. The catalyst 11 can therefore, for example, also simply be placed on an already existing conventional ignition chimney, i.e. an ignition chimney which has not yet been equipped with a catalyst 11, so that the problem of the emission of carbon monoxide can be remedied very quickly and without any conversion measures.

[0039] In FIGS. 1 and 2, it is shown that a holder 16 for the catalyst 11 is formed in or on the housing 3, namely in the upper region of the upper combustion chamber 6, wherein the catalyst 11 is held by the holder 16, in the present case releasably held by the holder 16. In FIG. 1, the catalyst 11 rests loosely on the holder 16. The catalyst 11 can be easily handled by means of a mounting bracket 17, i.e. removed from the holder 16 and placed on the holder 16. In FIG. 2, the catalyst 11 is additionally held in the housing 3 of the ignition chimney 1 by a fire-proof chimney band 28.

[0040] FIG. 2 further shows that an opening 18 is formed in the housing 3 in the side region of the upper combustion chamber 6, through which the fuel 2 can be introduced into the upper combustion chamber 6 and removed from the upper combustion chamber 6; for this, the catalyst 11 does not have to be removed beforehand. The opening 18 can be closed by a closing element 19 in the form of a flap. This has the advantage that the catalyst 11 does not have to be removable from the housing 3 of the ignition chimney 1.

[0041] The upper part of a ignition chimney 1 is shown in FIG. 3, wherein the catalyst 11 is part of a catalyst unit 20 with a tube 21 and the catalyst 11 is held in the tube 21, wherein the tube 21 extends between a first tube opening 22 and a second tube opening 23, wherein, in the assembled state of the catalyst unit 20, the first tube opening 22 is arranged below the second tube opening 23, wherein the catalyst 11 is held in the cross-section of the tube 21 with a holding device 24 between the first tube opening 22 and the second tube opening 23, wherein the tube 21 is slipped over the housing 3 in the region of the upper combustion chamber 6 to achieve the assembled state of the catalyst unit 20.

[0042] In the illustrated embodiment, the catalyst 11 occupies over 90% of the cross-section of the tube 21.

[0043] In FIG. 3, the holding device 24 of the catalyst unit 21 is formed in the tube 21 as an at least partially circumferential collar, wherein the collar has interruptions. The catalyst 11 is supported on the collar or collar elements in the assembled state on the basis of its weight, and further the catalyst 11 is positively held in the holding device 24 so that it is securely held in the holding device 24 and cannot fall out of it even if the catalyst unit 20 is removed from the housing 3 of the ignition chimney 1 and moved.

REFERENCE NUMBERS

[0044] 1 Ignition chimney [0045] 2 Fuel [0046] 3 Housing [0047] 4 Lower combustion chamber [0048] 5 Igniter [0049] 6 Upper combustion chamber [0050] 7 Separator [0051] 8 Upper side of separator [0052] 9 Igniter exhaust [0053] 10 Electric heating element [0054] 11 Catalyst [0055] 12 Fuel exhaust gases [0056] 13 Ambient air [0057] 14 Inlet side of the catalyst [0058] 15 Outlet side of the catalyst [0059] 16 Holder [0060] 17 Mounting bracket [0061] 18 Opening [0062] 19 Closure element [0063] 20 Catalyst unit [0064] 21 Tube [0065] 22 First tube opening [0066] 23 Second tube opening [0067] 24 Holding device [0068] 25 Handle [0069] 26 Heat shield [0070] 27 Electrical connection element [0071] 28 Fire-proof chimney band