CREMATORIUM OVEN

Abstract

The invention relates to a crematorium oven 1 comprising at least one combustion chamber 2 with a ceiling, wall 2.1 and base 3 on which to place the object to be cremated, a heat supply system 4, a combustion air supply 5 and a flue gas outlet 6. Within the ceiling and/or the wall 2.1 and/or the base 3 of the combustion chamber 2 at least one combustion air supply channel 7 and at least one flue gas return channel 8 are provided whereby the flue gas return channel 8 in the ceiling, and/or the wall 2.1 and/or the base 3 has an inlet 8.1 and an outlet 8.2. In the ceiling and/or wall 2.1 and/or in the base 3 of the combustion chamber 2 the at least one combustion air supply channel 7 opens into the at least one flue gas return channel 8, so that with the supplied combustion air a suction effect of the combustion air supply into the combustion chamber 2 is brought about. In this way at least part of the flue gas produced during the combustion process is drawn into the inlet 8.1 of the flue gas return channel 8 and emitted through the outlet 8.2 of the flue gas return channel 8 into the combustion chamber 2 and is thereby supplied to the combustion process again.

Description

TECHNICAL FIELD

The present invention relates to a crematorium oven.

PRIOR ART

Crematorium ovens are already known from the prior art. They essential comprise a combustion chamber with a ceiling, wall and base on which to place the object to be cremated, a heat supply system for heating the combustion chamber as well as a combustion air supply and a flue gas outlet.

Crematorium ovens are also known which have a combustion chamber with two combustion chamber sections, whereby in the first combustion chamber section preliminary incineration of the object to be cremated takes place, with subsequent incineration of the remains from the first combustion chamber section taking place in the second combustion chamber section. Here, the cremation remains from a first incineration phase remaining in a first combustion chamber section are transferred to the second combustion chamber section manually or with a removal device, whereby the heat produced in the first combustion section to incinerate a second object for cremation is used for the subsequent incineration of the cremated remains in the second combustion chamber section.

In addition, through DE 601 06 043 T2 a rotating combustion system, with a flue gas return is known, in which part of the flue gas is diverted at the central flue gas outlet and returned to the combustion process via the central combustion air supply.

The disadvantage of the solutions known from the prior art is that crematorium ovens have a low efficiency so that during combustion a high energy supply through the heat supply system is necessary and the fuel consumption is therefore high. Furthermore the duration of a cremation is very long as it is determined by the difficult and slowly burning parts of the object being cremated.

DESCRIPTION OF THE INVENTION

This is the starting point of the invention. The object of the invention, as characterised in the claims, is to provide a crematorium oven, which allows the energy-efficient and rapid incineration of an object to be cremated.

According to the invention this object is achieved by way of the crematorium oven according to claim 1. Further advantageous details, aspects and embodiments of the present invention are set out in the dependent claims, the description, the examples and the drawings.

The present invention provides a crematorium oven comprising at least one combustion chamber with a ceiling, wall and a base on which to place the object to be cremated, a heat supply system, a combustion air supply and a flue gas outlet. Within the ceiling and/or the wall and/or the base of the combustion chamber at least one combustion air supply channel and at least one flue gas return channel are provided, whereby the flue gas return channel in the ceiling, and/or the wall and/or the base has an inlet and an outlet. In the ceiling and/or wall and/or in the base of the combustion chamber the at least one combustion air supply channel opens into the at least one flue gas return channel, so that the supplied combustion air causes a suction effect of the combustion air supply into the combustion chamber. In this way at least part of the flue gas produced during the combustion process is drawn into the inlet of the flue gas return channel and emitted through the outlet of the flue gas return channel into the combustion chamber and is thereby supplied to the combustion process again.

On the one hand the return of flue gas in accordance with the invention brings about a return of the thermal energy contained in the flue gas, and on the other hand the subsequent incineration of not fully burned and/or still burnable components in the flue gas. Mixing of the flue gas returned in the flue gas return channel with the combustion air takes place and thereby preheats the combustion air. Further preheating of the combustion air is brought about in that the flue gas return channel and the combustion air supply channel are arranged in the ceiling and/or the wall and/or the base of the combustion chamber. During operation of the crematorium these parts are at very high temperatures so that the temperature of the combustion gas is considerably increased. At sufficiently high temperatures the gas mixture ignites on that a flame emerges at the outlet to the flue gas return channel.

As a result of the flue gas return in accordance with the invention the efficiency of the crematorium oven is increased considerably. The energy requirement of a crematorium oven can be reduced by 80% and more. Whereas conventional crematorium ovens require around 30 m³ to 35 m³ of natural gas to incinerate an object for cremation, the crematorium oven in accordance with the invention consumes 6 m³ to 7 m³, in extreme cases even 3 m³ to 5 m³ natural gas.

The combustion air supply channels can be arranged in any number of loops within the ceiling and/or the wall and/or the base of the combustion chamber. The longer the path of the combustion air supply channels and the longer the supply time of the combustion air is extended, the more thermal energy is taken up by the combustion air through the strongly heated parts of the combustion chamber. Through preheating of the combustion air the object for cremation is more completely incinerated.

Particularly preferably several flue gas return channels and/or several combustion air supply channels are provided, which are preferably locally arranged evenly distributed along the object to be cremated. In this way targeted, locally-distributed flue gas return and an improvement in the burning of difficult to burn and/or slowly burning parts of the object to be cremated can take place.

In addition, particularly when using several flue return channels, due to the gas flowing into the combustion chamber from different directions turbulences occur in the combustion chamber which results in further improved incineration.

In a preferred embodiment at least one combustion air supply channel opens into several flue gas return channels. Through the already discussed mixing of the flue gas being returned in the flue gas return channel with the combustion air, and the ignition of the gas mixture that takes place at sufficiently high temperatures, a flame emerges at the outlet of the flue gas return channel which in the case of a suitably selected arrangement of the outlets of the flue gas return channels can be directed directly at the object to be cremated, more particularly the difficult to burn or slowly burning parts of the object to be cremated.

In a preferred embodiment all the combustion air supply channels are connected to a central combustion air supply. Through this central combustion air supply, pressurised combustion air is supplied to the combustion air supply channels by way of a fan, for example, which brings about a suction effect in the flue gas return channels connected to the combustion air supply channels. As a result of the central supply of the combustion air supply channels with combustion air, a simpler design of the crematorium oven is achieved.

In the ceiling and/or in the walls and/or in the base of the combustion chamber the flue gas return channels have an inlet and an outlet. In accordance with a preferred embodiment the inlet of a flue gas return channel arranged in the wall is arranged above the outlet. This arrangement ensures that gases produced during the incineration process of the object to be cremated are drawn in at the inlet of the flue gas return channel in the upper part of the combustion chamber or combustion chamber sections, and emitted, preferably already ignited, in the lower area of the object to be cremated which burns more slowly, so that as high a heat exposure as possible acts of the difficult to burn parts of the object to be cremated, which thereby results in cremation that is efficient and reduced in terms of time.

In a second preferred form of embodiment the combustion chamber has a first and a second combustion chamber section, whereby the first combustion chamber section is designed for the preliminary burning of the object to be cremated and the second combustion chamber section for the subsequent incineration of the cremated remains and/or mineralisation of the ashes from the first combustion chamber section. In this way a further increase in efficiency is achieved, as the heat produced during a further incineration process in the first combustion chamber section can be used for afterburning in the second combustion chamber section.

In a further preferred embodiment the base brings about an at least partial separation of the combustion chamber into a first and a second combustion chamber section, whereby the combustion gases produced in the first combustion chamber section are drawn off via the second combustion chamber section and the central flue gas outlet connected thereto. A flue gas return channel passes through the base in such a way that a continuous connection between the first and second combustion chamber section is produced. As a result of having the flue gas return channels in the base, flue gases from the second combustion chamber section are returned to the first combustion chamber section and through mixing with combustion air are supplied, preferably ignited, to the underside of the object to be cremated so that incineration of the underside of the latter takes place.

In a particularly preferred embodiment the base has several elevations which are designed so that the object to be cremated is a placed at a distance from the base. Preferably the elevations are each provided adjacent to the outlets of the flue gas return channels. In this way the gases which are mixed with the combustion air and preferably ignited can flow around the object to be cremated and/or the flames emerging from the outlets of the flue gas return channels can blaze around the underside of the object to be cremated so that especially these slowly burning areas undergo accelerated incineration through the increased heat effect.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail below by way of examples of embodiment with reference to the drawings. However, it is expressly pointed out that the invention is not intended to be restricted to the shown example.

FIG. 1 shows as an example a schematic lateral cross-section of a crematorium oven in accordance with the invention;

FIG. 2 shows as an example a partial cross-section through the wall of the crematorium oven in FIG. 1 along line A-A.

FIG. 3 shows as an example a partial cross-section along the base of the crematorium oven in FIG. 1.

WAYS OF IMPLEMENTING THE INVENTION

In FIG. 1 reference number 1 denotes a crematorium oven in accordance with the invention. Dashed lines indicate that the relevant object is not shown in the sectional plan, but is located in the walls or in the base of the crematorium oven. In the known manner the crematorium oven 1 has a combustion chamber 2, which is surrounded by a wall 2.1 on its outer circumference. In the shown example of embodiment the wall 2.1 is designed in several layers, namely an outer layer formed by a housing 2.2. and a second internally adjoining layer forming an insulation 2.3. Provided on the housing 2.2. of the crematorium oven 1 is a heat supply system 4 which supplies thermal energy to the combustion chamber 2. The heat supply system 4 is, more particularly, a burner, for example a gas or oil burner.

In order to make an incineration process possible within the combustion chamber the crematorium oven 1 also has a combustion air supply 5 and a flue gas outlet 6. Via the combustion air supply 5 pressurised air is supplied to the combustion chamber 2 by means of a fan for example. The combustion air can be fresh air, fresh air enriched with oxygen or also pure oxygen. The flue gases produced during combustion are removed from the combustion chamber 2 via the flue gas outlet 6 and a chimney preferably comprising a flue gas treatment device. In addition, a ceiling (not shown) and abase 3 on which the object to be cremated is placed for burning are provided in the combustion chamber 2.

In accordance with the invention in the ceiling and/or in the wall 2.1 and/or in the base 3 of the combustion chamber 2 at least one combustion air supply channel 7 and at least one flue gas return channel 8 is provided, whereby these channels 7, 8 are connected to each other in such a way that through the suction effect of the combustion air supply into the combustion chamber 2 at least part of the flue gas produced during the incineration is returned to the combustion process via the flue gas return channel 8.

In the shown example of embodiment a branched network of combustion air supply channels 7 is provided in the wall 2.1 of the combustion chamber 2 and in the base 3. The combustion air supply channels 7 are all connected to the central combustion air supply 5 so that via this combustion air supply 5 pressurised combustion air is distributed into the combustion air supply channel 7 by way of a fan for example.

Also provided within the wall 2.1 of the combustion chamber 2 and in the base 3 are flue gas return channels 8, each with an inlet 8.1 and an outlet 8.2. The flue gas return channels 8 within the wall 2.1 of the combustion chamber 2 run parallel to the vertical axis HA of the crematorium oven 1 and can be formed in the insulation 2.3 and/or casing 2.2 or be formed by tubular elements arranged within the combustion chamber 2. In the shown example of embodiment the flue gas return channels 8 run at an acute angle to the vertical axis HA and preferably pass completely through the base. The flue gas return channels 8 are preferably locally distributed along the lateral axis QA of the combustion chamber 2.

To produce a suction effect within the flue gas return channels 8 the combustion air supply channel 7 or branches from this combustion air supply channel 7 are each connected to the individual flue gas return channels 8 in such a way that through the suction effect the flue gas produced by the incineration is drawn into the inlet 8.1 and emitted though the outlet 8.2.

In a preferred example of embodiment one combustion air supply channel 7 or a branch from this combustion air supply channel 7 opens into several flue gas return channels 8. In this way mixing of the drawn flue gas with freshly supplied combustion air occurs in the flue gas return channels 8 and after ignition of the gas mixtures afterburning takes place.

Particularly preferably the base 3 is arranged within the combustion chamber 2 in such a way that the combustion chamber 2 is divided into a first and a second combustion chamber 2a, 2b. In relation to the vertical axis HA of the crematorium oven 1 the first combustion chamber section 2a is preferably arranged above the second combustion chamber section 2b. Through the base 3 the combustion chamber 2 is only partially divided into combustion chamber sections 2a, 2b so that gas produced in the first combustion chamber section 2a escapes, as indicated by the arrow 10, via the second combustion chamber 2b and the flue gas outlet 6 provided there.

The object to be cremated is introduced into the first combustion chamber section 2a in such a way that after a heating up phase of the crematorium oven 1 through the supply of energy from the heat supply system 4 it is placed at least partially on the base 3. Preferably the object to be cremated does not lie completely on the base 3 but is held on elevations 9 at a distance from the base 3. Subsequently, in a first incineration phase the object to be cremated is burned in the first combustion chamber section 2a. After the first incineration phase, the remaining, not completely incinerated remains of the object to be cremated are transferred to the second combustion chamber section 2b for afterburning in a second incineration phase, so that after the second incineration phase complete cremation of the object to be cremated has taken place.

FIG. 2 shows a flue gas return channel 8 incorporated into the wall 2.1 of the combustion chamber 2 with a combustion air supply channel 7 opening into it. The flue gas return channel 8 has an inlet 8.1 and an outlet 8.2, whereby the inlet 8.1 is provided above the outlet 8.2. In the shown example of embodiment both the flue gas return channel 8 as well as the combustion air supply channel 7 run within the insulation 2.3.

The flue gas return channel 8 essentially comprises three channel sections 8.3, 8.4 and 8.5 running in an approximately straight line, whereby the first channel section 8.3 approximately runs perpendicularly to the second channel section 8.4 and the second channel section 8.4 runs approximately perpendicularly to the third channel section 8.5. The first and third channel sections 8.3, 8.5 are in parallel and at a distance from one another and at the free end form the inlet 8.1 and the outlet 8.2 respectively. The first to third channel sections 8.3, 8.4 and 8.5 are connect to a continuous flue gas return channel 8 via arched channel connection sections. In the arched channel connection section between the second 8.4 and the third channel section 8.5 the combustion air supply channels 7 or a branch from a combustion air supply channel 7 opens into the flue gas return channel 8.

Through the supply of combustion air under pressure from the combustion air supply channel 7 in the direction of the outlet 8.2 a suction effect is produced in the first and second channel section 8.3 and 8.4 of the flue gas return channel 8. As a result of this, as shown by the arrow 11, flue gas already produced by burning is drawn into the flue gas return channel 8. At the point where the flue gas return channel 8 joins the combustion air channel 7 the drawn-in gas is mixed with fresh combustion air so that at the temperature predominating in the combustion chamber 2 the gas mixture is already ignited in the third channel section 8.5 of the flue gas return channel 8 so that at the outlet 8.2 a flame emerges. The outlets 8.2 are preferably arranged in such a way in relation to the object to be cremated that the flames emerging at the outlets 8.2 act directly on the object to be cremated.

FIG. 3 shows a sectional view of the base of the crematorium oven 1 in accordance with the invention. In the lateral direction the base 3, which at least partially separates the first combustion chamber section 2a from the second combustion chamber section 2b is traversed by at least one flue gas return channel 8 which has an inlet 8.1 on its underside and an outlet 8.2 on its upper side. In the area of the outlet 8.2 the base 3 has an elevation 9, which in the shown example of embodiment is in the shape of a tongue. The tongue-shaped elevation 9 is designed in such a way that at the top the outlet 8.2 is covered by the elevation 9. This effectively prevents combustion residues falling through from the first combustion chamber section 2a into the second combustion chamber section 2b.

Also provided in the base 3 is a combustion air supply channel 7 or a branch from a combustion air supply channel 7 which opens into the flue gas return channel 8. Through the supply of pressurised combustion air in the combustion air supply channel 7 a suction effect is produced at the inlet 8.1 of the flue gas return channel 8 which causes flue gas to be returned from the second combustion chamber section 2b into the first combustion chamber section 2a. In the combustion channel 8 freshly supplied combustion air is mixed with the returned flue gas from the second combustion chamber section 2b and at a sufficiently high temperature is ignited within the combustion chamber 2 so that a flame is produced in the flue gas return channel 8 and, more particularly, at the outlet 8.2. The flames emerging at the outlet 8.2 surround the bottom of object to be cremated resulting in better incineration thereof at the places where the body is resting on the base of the coffin. This effect is assisted decisively by the object to be cremated being positioned at a distance from the base 3 through the elevations 9.

Having thus described the invention, it is now claimed:

LIST OF REFERENCE NUMBERS

1 Crematorium oven

2 Combustion chamber

2a First combustion chamber section

2b Second combustion chamber section

2.1 Wall

2.2 Casing

2.3 Insulation

3 Base

4 Heat supply system

5 Combustion air supply

6 Flue gas outlet

7 Combustion air supply channel

8 Flue gas return channel

8.1 Inlet

8.2 Outlet

8.3 First channel section

8.4 Second channel section

8.5 Third channel section

9 Elevation

VA Vertical axis

LA Lateral axis

Claims

1. Crematorium oven (1) comprising at least one combustion chamber (2) with a ceiling, wall (2.1) and base (3) on which to place the object to be cremated, a heat supply system (4), a combustion air supply (5) and a flue gas outlet (6),

whereby within the ceiling and/or the wall (2.1) and/or the base (3) of the combustion chamber (2) at least one combustion air supply channel (7) and at least one flue gas return channel (8) are provided,

whereby the flue gas return channel (8) in the ceiling and/or the wall (2.1) and/or the base (3) has an inlet (8.1) and an outlet (8.2)

whereby in the ceiling and/or wall (2.1) and/or in the base (3) of the combustion chamber (2) the at least one combustion air supply channel (7) opens into the at least one flue gas return channel (8), so that with the supplied combustion air a suction effect of the combustion air supply into the combustion chamber (2) is brought about,

whereby at least part of the flue gas produced during the combustion process is drawn into the inlet (8.1) of the flue gas return channel (8) and emitted through the outlet (8.2) of the flue gas return channel (8) into the combustion chamber (2) and is thereby supplied to the combustion process again.

2. Crematorium oven according to claim 1 characterised in that at least one combustion air supply channel (7) opens into several flue gas return channels (8).

3. Crematorium oven according to claim 1 characterised in that the inlet (8.1) of the at least one flue gas return channel (8) is arranged in the wall (2.1) of the combustion chamber above the outlet (8.2) of the at least one flue gas return channel (8)

4. Crematorium oven according to claim 1 characterised in that the combustion chamber (2) has a first and a second combustion chamber section (2a, 2b) whereby the first combustion chamber section (2a) is designed for the incineration of the object to be cremated and the second combustion chamber section (2b) is designed for the afterburning of the ashes and/or the cremated remains from the first combustion chamber section (2a).

5. Crematorium oven according to claim 4 characterised in that the base (3) brings about at least partial separation of the first combustion chamber section (2a) from the second combustion chamber section (2b).

6. Crematorium oven according to claim 5 characterised in that by way of at least one flue gas return channel (8) in the base (3) a connection between the first and the second combustion chamber section (2a, 2b) is produced.

7. Crematorium oven according to claim 6 characterised in that the base (3) has several elevations (9) for positioning the object to be cremated at a distance from the base (3).

8. Crematorium oven according to any one of claim 7 characterised in that the flue gas outlet (6) is connected to the second combustion chamber section (2b).

9. Crematorium oven according to claim 2 characterised in that the inlet (8.1) of the at least one flue gas return channel (8) is arranged in the wall (2.1) of the combustion chamber above the outlet (8.2) of the at least one flue gas return channel (8).

10. Crematorium oven according to claim 2 characterised in that the combustion chamber (2) has a first and a second combustion chamber section (2a, 2b) whereby the first combustion chamber section (2a) is designed for the incineration of the object to be cremated and the second combustion chamber section (2b) is designed for the afterburning of the ashes and/or the cremated remains from the first combustion chamber section (2a).

11. Crematorium oven according to claim 3 characterised in that the combustion chamber (2) has a first and a second combustion chamber section (2a, 2b) whereby the first combustion chamber section (2a) is designed for the incineration of the object to be cremated and the second combustion chamber section (2b) is designed for the afterburning of the ashes and/or the cremated remains from the first combustion chamber section (2a).

12. Crematorium oven according to claim 2 characterised in that by way of at least one flue gas return channel (8) in the base (3) a connection between the first and the second combustion chamber section (2a, 2b) is produced, wherein the combustion chamber (2) has a first and a second combustion chamber section (2a, 2b) whereby the first combustion chamber section (2a) is designed for the incineration of the object to be cremated and the second combustion chamber section (2b) is designed for the afterburning of the ashes and/or the cremated remains from the first combustion chamber section (2a).

13. Crematorium oven according to claim 3 characterised in that by way of at least one flue gas return channel (8) in the base (3) a connection between the first and the second combustion chamber section (2a, 2b) is produced, wherein the combustion chamber (2) has a first and a second combustion chamber section (2a, 2b) whereby the first combustion chamber section (2a) is designed for the incineration of the object to be cremated and the second combustion chamber section (2b) is designed for the afterburning of the ashes and/or the cremated remains from the first combustion chamber section (2a).

14. Crematorium oven according to claim 4 characterised in that by way of at least one flue gas return channel (8) in the base (3) a connection between the first and the second combustion chamber section (2a, 2b) is produced.

15. Crematorium oven according to claim 4 characterised in that the flue gas outlet (6) is connected to the second combustion chamber section (2b).

16. Crematorium oven according to claim 5 characterised in that the flue gas outlet (6) is connected to the second combustion chamber section (2b).

17. Crematorium oven according to claim 6 characterised in that the flue gas outlet (6) is connected to the second combustion chamber section (2b).