EP4589197A1

EP4589197A1 - Cremation chamber with emission treatment

Info

Publication number: EP4589197A1
Application number: EP24213252.0A
Authority: EP
Inventors: Francisco Perez Bueno
Original assignee: Ideter Sl
Current assignee: Ideter Sl
Priority date: 2024-01-19
Filing date: 2024-11-15
Publication date: 2025-07-23
Also published as: ES1306517Y; ES1306517U

Abstract

1.- Cremation chamber (1) with emission treatment, of the type comprising:
- a combustion chamber (2), with a first heat source (2a) for combustion,
- a post-combustion chamber (3) arranged at the outlet of the combustion chamber (2) and connected thereto, and provided with a second heat source (3a) for post-combustion, and
- a combustion gas outlet (4) provided after the post-combustion chamber (3); comprising a particle filter (5) arranged therein, after the combustion chamber (2).

Description

OBJECT OF THE INVENTION

This invention refers to a cremation chamber which can be used in the incineration of corpses of dead people or animals

BACKGROUND TO THE INVENTION

During the incineration of corpses, a series of pollutants are produced which are typical of the physical-chemical transformation that takes place. These pollutants will be present in a greater or lesser proportion depending on different factors. The main pollutants, or at least those that have the greatest impact on people's health, are the following:

▪ Solid particles of different sizes (PM10, PM5, PM2.5)
▪ Nitrogen oxides, commonly know as NOx when evaluated as a whole as the sum of NO and NO₂.
▪ Sulphur dioxide SO₂.
▪ Carbon monoxide CO.
▪ Hydrogen chloride HCL.
▪ Total organic compounds, TOC, or according to the criterion, volatile organic compounds in gaseous currents (VOC)
▪ Dioxins and furans (PCDD+PCDF).
▪ Heavy metals such as Hg (mercury), Pb (lead), Sb (antimony), etc.

Out of all these pollutants, there are some that depend directly on the quality of combustion, which must occur in the presence of excess oxygen within a point of equilibrium, in order to achieve - together with the right temperature - thermal oxidation that enables the decomposition of these elements into others that are less harmful to health and the environment.
The pollutants that depend on the quality of combustion are mainly carbon monoxide (CO), as well as total organic compounds (TOC), which are, ultimately, the hydrocarbons present in the emission that have not been broken down into their most basic elements.
There are also other pollutants that depend directly on operating conditions, such as dioxins and furans, considered to be persistent organic pollutants (POPs) and which are formed within a temperature range of between 250 and 550°C, decomposing at temperatures above 550°C but being able to reform if the temperature drops for a certain time. Since human or animal incineration processes are subject to thermal oxidation of gases above 850°C in the presence of excess O₂ in the post-combustion chamber, with a residence time in that chamber of at least 2 seconds, the gases eventually emitted into the atmosphere will in practice be absent of Dioxins and Furans, or at least with a content well below the stipulated emission limit values. Therefore, today's furnaces comprise a combustion chamber, with a first heat source for combustion, a post-combustion chamber arranged at the outlet of the combustion chamber and connected thereto, and they have a second heat source for post-combustion and a combustion gas outlet (connectable to a chimney) provided after the post-combustion chamber.
With regard to heavy metals, since they are inherent or constituent elements of the very product to be incinerated (coffin assembly and body, for example), new quantities of such pollutants cannot be produced or generated during combustion, beyond gasifying or carrying away the existing quantity. Under current legislation on the use of coffins at European level (UNE 190001) for cremation, the use of varnishes containing heavy metals is prohibited, and only water-based varnishes may be used in the case of the most common coffins. Therefore, the heavy metals present in the final emissions into the atmosphere will come mainly from those released by the body to be cremated, the quantity of which is so small that in many cases they are below the measurement range not only of the stipulated limit value, but of the measuring device itself.
With this, finally, the suspended solid particles and NOx are the most limiting pollutants in the process, which sometimes even after combustion has occurred in the presence of coherent oxygen, we can find that in the flow of gases emitted into the atmosphere, their presence may be very close to the stipulated limit value.
NOx is produced mainly in 2 very distinct stages: a first stage where combustion NOx is generated, this being inherent to the fuel to be burned and the way it is done, and a thermal NOx which is produced afterwards by combining with the excess air supplied to the combustion and at high temperatures. The first can be reduced by installing low NOx burners, where the combustion point is delayed and preheated air can be supplied. The second can be controlled by making the maximum temperature in the post-combustion chamber not so high and by supplying only the air strictly necessary to not increase the amount of nitrogen in the final mixture. However, and according to the international trend towards the reduction of emissions, the value of this pollutant should as far as possible be limited.

DESCRIPTION OF THE INVENTION

The cremation chamber with emission treatment, as in the invention, is of the type comprising:

a combustion chamber, with a first heat source for combustion,
a post-combustion chamber arranged at the outlet of the combustion chamber and connected thereto, and provided with a second heat source for post-combustion, and
a combustion gas outlet (connectable to a chimney) provided after the post-combustion chamber, and which in accordance with the invention, also comprises a particle filter arranged therein, after the combustion chamber (i.e., in the post-combustion chamber or after the post-combustion chamber).

In this way, the filter generates a shock barrier, which will largely prevent particles of different sizes and composition from passing through it, depending on its final layout, grid opening (passage section), etc. Thus, by being integrated into the cremation chamber itself, in addition to versatile emission treatment appropriate to each need - especially focused on the reduction of pollutants due to solid particles (and optionally also NOx), the rest can be controlled by means of the calibration and operation of the cremation chamber itself -, which largely solves the problem at the level of emissions, a reduced level of space and investment compared to complex filtration systems.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows an external view of the cremation chamber of the invention.
Figure 2 shows an isometric section of the cremation chamber of the invention.
Figure 3a shows a longitudinal sectional view of the cremation chamber of the invention, in a variant with a filtering wall (particle retention) and which can incorporate a catalyst in its composition.
Figure 3b shows a longitudinal sectional view of the cremation chamber of the invention, in another variant where there is a catalyst in a wall arranged behind the filter.
Figures 4 and 5 show two possible embodiments of blocks for materialising the filter by means of a wall.
Figure 6 shows a section of the block shown in Figure 4, and a detail of that section.

DESCRIPTION OF A PRACTICAL REALISATION OF THE INVENTION

The cremation chamber (1) with emission treatment, as in the invention, is of the type comprising:

a combustion chamber (2), with an access for coffins (20) and a first heat source (2) for combustion,
a post-combustion chamber (3) arranged at the outlet of the combustion chamber (2) and connected thereto, and provided with a second heat source (3a) for post-combustion,
a combustion gas outlet (4) connectable to a chimney, provided after the post-combustion chamber (3), and which in accordance with the invention, also comprises a particle filter (5) arranged therein, after the combustion chamber (2).

In a first variant of the invention shown in the figures, the filter (5) is located in the post-combustion chamber (3), delimiting a front post-combustion sub-chamber (3b), where the post-combustion itself takes place, and a rear post-combustion sub-chamber (3c), where the gas flow is finally stabilised before the exit through the chimney, with the settling of particles that may have passed through the filter.
In a second variant of the invention, the filter (5) is arranged in a treatment chamber, not shown, arranged after the post-combustion chamber (3) and before the gas outlet (4), which enables greater control over the reduction of pollutants, and an improvement in its maintenance.
In a very preferential and advantageous fashion, it is preferred that the particle filter (5) comprises a reticulated wall, since it has a better resistance to high temperatures, without deteriorating. Likewise, it is preferred that this reticulated wall comprises an assembly based on a plurality of blocks (50) (see Figs. 4 and 5) equipped with reticles formed by cells (51) passing along their entire length, which enables walls of different configurations to be made, adapted to different configurations of the cremation chamber. Said blocks (50) can be prismatic in shape like bricks, and/or cylindrical. These blocks (50) are preferably materialised in ceramic materials (cordierite-mullite, etc.). This material provides high resistance to temperature at the mechanical and structural level (over 1200°C), so they will not require significant corrective maintenance, and will be able to maintain their stability for a reasonable period of time, provided that preventive maintenance is carried out, which will focus mainly on cleaning them.
The invention has provided for the possible additional arrangement of a catalyst (based on zeolites or various materials, depending on the pollutant to be reduced) interposed in the gas flow, which will enable the reduction of other pollutants such as thermal NOx or CO. This catalyst can be produced by coating (6) the filter (5) (see Fig. 6) - which can be done on the blocks themselves, if necessary, for example by means of a surface impregnation - or by a facing wall (7), arranged after the particle filter (5) (see Fig. 3b), carrying out the process in two stages, and in this other configuration better protecting against premature clogging by particles, since they are retained in the filter.
Since cleaning is essential for the proper functioning of the invention, provision has been made for access panels (8) for filter and/or catalyst maintenance, for manual cleaning, for example, by blowing with a compressor, once the cremation chamber is not operational and in safe conditions, or for the collection of ashes. These panels provide access to the post-combustion chamber or to the possible independent chamber that would contain the blocks.
In addition, the arrangement has been foreseen of possible cleaning inlets which blow counter-current compressed air (see Figs. 3a and 3b), on the back of the filter (5) (of the wall made with the filter blocks if applicable), as well as additional closing elements, not shown, in other holes in the cremation chamber (gas outlet). Inserted through these cleaning inlets (9) will be a lance connected at one end to a compressed air line and with a tip designed to propel the compressed air in a counter-current direction against the filter, allowing the particles and pollutants deposited in the reticles, to be descaled, with any maintenance panels that may exist and the additional closing elements remaining closed during operation.
Having sufficiently described the nature of the invention, as well as the manner in which it is carried out in practice, it should be noted that the provisions mentioned above and shown in the attached drawings are subject to detailed modifications as long as they do not alter the fundamental principle.

Claims

Cremation chamber (1) with emission treatment is of the type comprising:
- a combustion chamber (2), with a first heat source (2a) for combustion,

- a post-combustion chamber (3) arranged at the outlet of the combustion chamber (2) and connected thereto, and provided with a second heat source (3a) for post-combustion, and

- a combustion gas outlet (4) provided after the post-combustion chamber (3), characterised in that it comprises a particle filter (5) arranged therein, after the combustion chamber (2).
Cremation chamber (1) with emission treatment according to claim 1, where the filter (5) is arranged in the post-combustion chamber (3).
Cremation chamber (1) with emission treatment according to claim 1, where the filter (5) is arranged in a treatment chamber, arranged after the post-combustion chamber (3) and before the gas outlet (4).
Cremation chamber (1) with emission treatment according to any of the above claims, where the particle filter (5) comprises a reticulated wall.
Cremation chamber (1) with emission treatment according to claim 4, where the reticulated wall comprises an assembly based on a plurality of blocks (50) equipped with reticles formed by passage cells (51) along its entire length.
Cremation chamber (1) with emission treatment according to claim 6, where the blocks (50) have a selected shape, either:
- prismatic,

- cylindrical.
Cremation chamber (1) with emission treatment according to claim 5 or 6, where the blocks (50) are made in ceramic materials.
Cremation chamber (1) with emission treatment according to any of the above claims, which additionally comprises a catalyst interposed in the flow of gases.
Cremation chamber (1) with emission treatment according to claim 8, where the catalyst is made by means of a coating (6) of the filter (5).
Cremation chamber (1) with emission treatment according to claim 8, where the catalyst is made by a facing wall (7), arranged next to the particle filter (5).
Cremation chamber (1) with emission treatment according to any of the above claims, comprising access panels (8) for maintenance.
Cremation chamber (1) with emission treatment according to any of the above claims, comprising cleaning inlets (9) by counter-current compressed air blowing on the back of the filter (5), as well as additional closing elements in other holes in the cremation chamber.