JPH0634117A - Incinerator - Google Patents

Abstract

PURPOSE:To improve a combustion characteristic in a secondary combustion chamber for municipal dust and industrial waste materials and to reduce a discharging of hard decomposing organic chloric compounds such as dioxine and the like. CONSTITUTION:An incinerator is constructed such that there are provided a feeding door, a discharging port connecting a primary combustion chamber 10 to either of a burner, g flue 17 or a chimney and a secondary cylindrical combustion chamber 13 connected vertically through the flue 17. Then, a center of the flue communicating with the primary combustion chamber 10 and the secondary combustion chamber 13 is eccentric against a center of cross sectional surface of the secondary combustion chamber 13, the discharged gas discharged from the primary combustion chamber is fed in a tangential direction of the secondary combustion chamber, an air supplying tank covers the secondary combustion chamber outside the secondary combustion chamber, the secondary combustion chamber is provided with an air nozzle for supplying combustion air so as to communicate with the air supplying tank and further the discharging port of the air nozzle is arranged to direct in the tangential direction of the secondary combustion chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an incinerator for municipal solid waste and industrial wastes, and in particular, improves combustion in a secondary combustion chamber to improve combustibility and to develop a persistent organic chlorine compound such as dioxins. It relates to an incinerator that decomposes.

[0002]

2. Description of the Related Art The generation of dioxins and the like in an incinerator for municipal waste and industrial waste is caused by CO in the incinerator combustion exhaust gas.
There is a strong positive correlation with the concentration, and CO
It is estimated that the concentration of dioxins increases as the concentration increases. In the guidelines for prevention of dioxin generation, which was announced by the Environment Improvement Division, Ministry of Health and Welfare, Ministry of Health and Welfare in December 1990, the CO concentration of incinerator combustion exhaust gas was used as an index of dioxin generation.

On the other hand, conventionally, a vertical two-stage incinerator has been used as an incinerator for municipal waste and industrial waste, particularly as a small incinerator. For example, various smokeless refuse incinerators described in Japanese Patent Publication No. 45-12638. The following types have been proposed. The structure of a conventional vertical two-stage incinerator will be described in detail with reference to FIGS. FIG. 6 is a front view of a conventional vertical two-stage incinerator, and FIG. 7 is a sectional view taken along line CC of FIG.

In FIGS. 6 and 7, an incinerator insertion door 3 and a lid 2 are openably and closably attached to one end of a primary combustion chamber 1 having a cylindrical shape, and the other end has an upper combustion side for supplying combustion air. An air vent 8 is provided. Further, a lower combustion air port 9 for supplying combustion air is provided in the hearth of the primary combustion chamber 1. A secondary combustion chamber 4 is installed above the primary combustion chamber 1 to gasify and burn the incinerator combustion exhaust gas so as to eliminate smoke. The primary combustion chamber 1 is connected via a flue 5 to the secondary combustion chamber 1. Is in communication with. The secondary combustion chamber 4 is provided with a burner 6 for supplying high-temperature gas or flame and a chimney 7 for discharging combustion exhaust gas of incineration material.

In the conventional vertical two-stage incinerator configured as described above, when the incineration object input door 3 is opened and the incineration object is placed on the hearth of the primary combustion chamber 1, the incineration object is generated. It is heated by the flame of a burner (not shown), and progresses with drying, burning, and post-burning over time. When the material to be incinerated burns, combustion exhaust gas from the material to be incinerated is generated, and the combustion exhaust gas from the material to be incinerated reaches the secondary combustion chamber 4 via the flue 5, where the combustion by the burner 6 burns the material to be incinerated. The unburned portion of the product combustion exhaust gas is burned and discharged from the chimney 7 to the outside of the system in a smokeless state.

[0006]

However, it was feared that these conventional vertical two-stage incinerators would not be able to obtain a sufficient effect in reducing the persistent chlorine compounds such as dioxins. That is, in the above-mentioned conventional vertical two-stage incinerator, in the secondary combustion chamber 4, part of the unburned gas containing CO, hydrocarbons, etc. is discharged without being decomposed,
Further, dioxins and the like generated in the incinerator are not decomposed and are discharged in a relatively large amount. Also, even if it undergoes thermal decomposition, it is not completely decomposed to carbon dioxide, it stops in a partially oxidized state, and unburned organic carbon content exists in the unburned gas, so temperature conditions in the exhaust gas treatment process in the latter stage, etc. As a result, dioxin is regenerated again.

The combustion exhaust gas from the incineration material is composed of unburned gas containing CO, hydrocarbons and the like, and combustion gas containing a relatively large amount of oxygen. In order to completely decompose carbon dioxide in an unburned gas containing CO, hydrocarbons and the like in the secondary combustion chamber, the secondary combustion chamber must be (1) in a high temperature atmosphere (800 to 1000 ° C.). (2) A sufficient residence time for decomposition can be secured. (3) The unburned gas and air are in a good mixed state. Is an essential condition. Particularly in the case of a high temperature gas, the viscosity of the gas becomes significantly higher than that at room temperature, so the mixing of unburned gas with air in (3) is important.

An object of the present invention is to solve the above-mentioned problems and to provide an incinerator capable of reducing the emission of hardly decomposable organic chlorine compounds such as dioxins to the utmost limit.

[0009]

SUMMARY OF THE INVENTION The present invention has a burner input door, a primary combustion chamber to which combustion air is supplied from combustion air supply means, and a burner, and communicates with the atmosphere. In the incinerator in which an exhaust port that connects to the flue or chimney is connected and the secondary combustion chamber having a cylindrical shape is connected in the vertical direction via the flue, the primary combustion chamber and the secondary combustion chamber are communicated. The center of the flue is made eccentric with respect to the center of the cross section of the secondary combustion chamber, and the incinerator combustion exhaust gas discharged from the primary combustion chamber is introduced in the tangential direction of the secondary combustion chamber, and the secondary combustion is performed. An air supply tank is arranged outside the chamber so as to cover the secondary combustion chamber, and an air nozzle is arranged to supply combustion air to the secondary combustion chamber so as to communicate with the air supply tank. The discharge port of the air nozzle is arranged so as to be oriented in the tangential direction of the secondary combustion chamber. That.

[0010]

Embodiments of the present invention will be described below with reference to FIGS. 1 is a cross-sectional view of an incinerator of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, FIG. 3 is a cross-sectional view taken along the line BB of FIG. 2, and FIGS. 4 and 5 are detailed views of an air nozzle. .

1 to 3, in one end of the primary combustion chamber 10, an incineration object door 12 and a lid 11 are openably and closably attached, and a lower combustion for supplying combustion air is provided in the hearth of the primary combustion chamber 10. An air port 18 is provided. A secondary combustion chamber 13 is installed above the primary combustion chamber 10 for gasifying and burning the incineration material combustion exhaust gas to eliminate smoke. The primary combustion chamber 10 is connected via a flue 14. Communicate with.

The secondary combustion chamber 13 has a cylindrical shape, the flue 14 is eccentric with respect to the center of the cross section of the secondary combustion chamber 13, and the incinerator combustion exhaust gas from the primary combustion chamber 10 is eccentric. Are arranged so that they can be introduced in the tangential direction of the secondary combustion chamber 13. Further, the secondary combustion chamber 13 is provided with a burner 15 for supplying high-temperature gas or flame at one end face relatively close to the flue 14 and an exhaust port 16 for burning incinerator combustion exhaust gas near the other end face, It communicates with the flue 17 through the outlet 16. Also,
An air supply tank 19 is arranged outside the secondary combustion chamber 13 so as to cover the secondary combustion chamber 13, and the secondary combustion chamber 13 and the air supply tank 19 communicate with each other via an air nozzle 20. In FIG. 4, in the air nozzle 20, the discharge port communicating with the secondary combustion chamber 13 is oriented in the tangential direction of the secondary combustion chamber 13.

In the embodiment shown in FIGS. 1 and 2, an example is shown in which the incineration object loading door 12 is opened and closed by manual operation to throw in dust, but a function of automatically opening and closing via a cylinder or the like is added. , May be automated. Further, the automated incinerator loading door may be arranged at the other end of the primary combustion chamber 10, and an incinerator loading device may be installed in front of the incinerator loading door. In the embodiment shown in FIGS. 3 and 4, the air nozzle 20 is a through hole provided on the wall surface of the secondary combustion chamber 13, and the example in which the through hole is oriented in the tangential direction of the secondary combustion chamber 13 has been shown. As shown in FIG. 5, a pipe 21 vertically penetrates a wall surface of the secondary combustion chamber 13, and a blind plate 22 is attached to an end surface of the pipe 21 on the side of the secondary combustion chamber 13 to make the pipe 21 blind. The opening 23 may be provided and the opening 23 may be oriented in the tangential direction of the secondary combustion chamber 13.

Next, with reference to FIGS. 1 to 4, the combustion state of the incinerator and the flow of the incinerator combustion exhaust gas in the incinerator of the present invention configured as described above will be described. The material to be incinerated in the primary combustion chamber 10 is heated by the flame of a burner (not shown) arranged in the primary combustion chamber 10, and progresses over time such as drying, burning, and post-combustion. At that time, the combustion air is supplied to the incineration object through the combustion air supply means. When the incineration object burns, incineration object combustion exhaust gas is generated, and the incineration object combustion exhaust gas is introduced into the secondary combustion chamber 13 via the flue 14. Since the center of the flue 14 is eccentric with respect to the center of the cross section of the secondary combustion chamber 13, a swirl flow of the incineration material combustion exhaust gas is generated in the secondary combustion chamber 13. Further, combustion air is supplied to the combustion exhaust gas from the incineration object from an air supply tank 19 arranged outside the secondary combustion chamber 13 through an air nozzle 20. Since the discharge port of the air nozzle 20 for supplying combustion air is oriented in the tangential direction of the secondary combustion chamber 13 in the same direction as the swirl flow of the incinerator combustion exhaust gas, combustion from the air nozzle 20 is performed. The swirling flow of the combustion exhaust gas for incineration is remarkably accelerated by the jet flow of the working air, that is, the swirling angular velocity is remarkably expanded and becomes a violent vortex.

Next, the combustion effect of the present invention will be described with reference to Table 1. The table shows the CO concentration of the incinerator combustion exhaust gas in the present invention. For comparison, the results of the conventional method are also shown in the table. In the present invention, the CO concentration of the combustion exhaust gas from incineration is 20 to 60 ppm, and the CO concentration is 95 to 250 in the conventional case.
It is ppm, and comparing the present invention and the conventional one, it can be seen that the CO concentration of the incinerator combustion exhaust gas in the present invention is remarkably small. Further, in the present invention, the target value of 100 ppm or less of the mechanized batch furnace determined by the guidelines for prevention of generation of dioxins has been achieved.

[Table 1]

EFFECTS OF THE INVENTION In the secondary combustion chamber, the swirling and swirling flow of the combustion exhaust gas of the incineration material greatly accelerates the stirring and mixing of the unburned gas and the combustion air, and the gas of the unburned gas As a result of the progress of chemical combustion, the concentrations of CO and hydrocarbons contained in the incinerator combustion exhaust gas discharged from the secondary combustion chamber can be significantly reduced. Furthermore, it is possible to decompose persistent organic chlorine compounds such as dioxins to the maximum. Further, as described above, in the secondary combustion chamber, by swirling and swirling the flow of the combustion incinerator combustion exhaust gas, the short path of the combustion incinerator combustion exhaust gas and the low temperature region (8
(Less than 00 ° C.) can be suppressed, and as a result, it is effective in establishing a high temperature atmosphere and ensuring decomposition time in the secondary combustion chamber. As is apparent from the above description, the present invention can significantly reduce the CO concentration in the combustion exhaust gas of incineration materials as compared with the conventional vertical two-stage incinerator, and the dioxin announced by the Ministry of Health and Welfare in December 1990. It is possible to provide an incinerator that can comply with guidelines such as generation prevention.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an incinerator of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

3 is a sectional view taken along line BB of FIG.

FIG. 4 Detailed view of air nozzle

[Fig. 5] Detailed view of the air nozzle

FIG. 6 is a front view of a conventional vertical two-stage incinerator.

7 is a sectional view taken along line CC of FIG.

[Explanation of symbols]

 10 Primary Combustion Chamber 13 Secondary Combustion Chamber 14 Flue 15 Burner 16 Discharge Port 17 Flue

Claims (1)

[Claims] 1. A primary combustion chamber having a material to be burned in, a combustion chamber to which combustion air is supplied from combustion air supply means, and a burner, and is connected to a flue or a chimney communicating with the atmosphere. In the incinerator in which the exhaust port is arranged and the secondary combustion chamber having a cylindrical shape is connected in the vertical direction through the flue, the center of the flue that connects the primary combustion chamber and the secondary combustion chamber is Eccentric with respect to the center of the cross section of the secondary combustion chamber, the incinerator combustion exhaust gas discharged from the primary combustion chamber is introduced in the tangential direction of the secondary combustion chamber, and an air supply tank is provided outside the secondary combustion chamber. An air nozzle is provided so as to cover the secondary combustion chamber, and an air nozzle for supplying combustion air to the secondary combustion chamber so as to communicate with the air supply tank is provided, and a discharge port of the air nozzle is An incinerator which is arranged so as to be oriented in the tangential direction of the secondary combustion chamber.