JPH02298716A - Incineration ash melting device - Google Patents

Abstract

PURPOSE:To reduce the NOx content in the titled device for refuse incineration ash by respectively connecting the secondary fuel nozzle to the upstream side wall surface of the melting chamber and the exhaust gas pipe to the upstream side all surface of the supplemental air nozzle. CONSTITUTION:The melting burner 2 in the melting chamber 8 burns under a nearly stoichiometric air condition to produce exhaust gas D1 and D2. The first exhaust gas D1 which occupies most of the exhaust gas is introduced into the preheating chamber 7, and most of NOx is reduced when it is burnt and reduced in the reduction burning zone F by the secondary fuel supplied from the secondary fuel nozzle 10. Further, the combustible components are completely burnt in the complete burning zone G by supplemental air supplied from the supplemental air nozzle 11. By this constitution, NOx can be reduced, and the pollution can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an incineration ash melting and processing apparatus that heats and melts waste incineration ash discharged from, for example, a waste incinerator and solidifies it with a burner to reduce its volume.

Conventional technology A burner-type melting device that melts and solidifies incinerated ash discharged from a garbage incinerator to reduce its volume and render it harmless has conventionally been used to transfer ash from an ash hopper 102 to a melting furnace 1 as shown in FIG.
The incinerated ash A put into the upstream side of the melting chamber 101 of No. 00 is sent to the downstream side by the butcher device 103, and
A melting burner 104 disposed on the upper wall heats the incinerated ash A to, for example, 1300° C. or higher to melt it, and flows the molten slag B together with the m-incinerated exhaust gas D from the outlet 105 to the slag cooling chamber 106, It's solidified. The combustion exhaust gas D flowing into the slag cooling chamber 106 at this time is transferred to the exhaust gas pipe 10
8 into the air preheater 107 and melt burner.

After heating the combustion air C supplied to 104, it was discharged into the atmosphere.

Problems to be Solved by the InventionAccording to the above-mentioned conventional configuration, for example, garbage incineration ash discharged from cities is heated to about 1300°C or higher and melted, but the exhaust heat of the combustion exhaust gas D from the melting burner 104 is In the air preheater, it was used only for heating the combustion air C of the melting burner 104, and was extremely wasteful.

Furthermore, the amount of NOx generated in the combustion exhaust gas D was extremely large.

The present invention is an incinerated ash that can recover and effectively utilize the exhaust heat of combustion exhaust gas to significantly reduce running costs, and also realize low NOx combustion to suppress the generation of NOX from combustion exhaust gas and achieve low pollution. The purpose of the present invention is to provide a melt processing apparatus.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention equips the melting chamber of a melting furnace with a melting burner, which melting burner melts the incinerated ash, and cools the molten slag downstream of the melting chamber. In the incinerated ash melting processing device that discharges into the chamber, a secondary fuel nozzle for supplying secondary fuel is provided on the upstream wall of the melting chamber, an additional air nozzle is provided on the upstream wall of the secondary fuel nozzle,
A combustion exhaust gas pipe is connected to the upstream wall surface of this additional air nozzle.

Effects According to the above configuration, the melting burner, the secondary fuel nozzle, and the additional air nozzle perform three-stage combustion to significantly reduce the amount of NOx generated, and moreover, the combustion exhaust gas can preheat the incinerated ash, allowing high efficiency operation. . In other words, ff1M! The burner is combusted with an air amount almost equal to the theoretical air amount to obtain a high combustion temperature and quickly melt the incinerated ash.
Secondary fuel is supplied from the secondary fuel nozzle to the & flow to perform reductive combustion and NOx is reduced to N2, and additional air is supplied from the additional air nozzle to the f & flow to completely burn the combustible matter.
The amount of NOx generated can be significantly suppressed.

Example An embodiment of the present invention will be described below with reference to FIG.

Reference numeral 1 denotes a melting furnace that heats and melts trash incineration ash A with a melting burner 2 to form molten slag B, and an ash popper 4 is disposed at an ash inlet 3 for incineration ash A on the upstream side, and On the side, a slag cooling chamber 6 is provided at the slag extraction port 5 for the molten slag B.

This melting furnace 1 is formed to be inclined downward from the upstream side to the downstream side, and a preheating chamber 7 is provided on the upstream side, and a melting chamber 8 is provided on the downstream side.
will be placed. At the lower part of the ash inlet 3, an ash 1 pulsating device 9 which can be freely moved in and out along the bottom wall 1b of the melting furnace 1 is arranged. The incinerated ash A is fed into the preheating chamber 7.

On the top wall 1a of the melting furnace 1, 181 is installed corresponding to the Wj melting chamber 8.
i1! A burner 2 is provided. Further, a secondary fuel nozzle 10 is provided on the downstream side and an additional air nozzle 11 is provided on the upstream side corresponding to the preheating chamber 7 to enable three-stage combustion, and furthermore, a first exhaust gas pipe 12A is provided on the upstream side of the preheating chamber 7. is connected. That is, the melting burner 2 has a theoretical air ratio of 0.85 to
The incinerated ash A is combusted with an air amount in the range of 1.15, preferably in the range of 0.90 to 1.10, and the incinerated ash A is rapidly melted at a high combustion temperature. Then, the first combustion exhaust gas D1 that accounts for most of the combustion exhaust gas is introduced into the preheating chamber 7, and first, secondary fuel for NOx reduction is additionally supplied from the secondary fuel nozzle 10 into the first combustion exhaust gas D1. Reductive combustion is performed in the absence of air, and most of the NOx generated in the melting chamber 8 is converted into N
2 (reduction combustion zone F), and then additional combustion air from the additional air nozzle 11 (0, F.

A) Complete combustion of combustible components by supplying E (complete combustion area G)
configured to do so. In addition, as shown by the imaginary line in FIG. 1, a partition wall 13 is installed vertically from the ceiling wall 1a between the additional air nozzle 12 and the secondary air nozzle 10 to divide the reduction combustion area F and the complete combustion area G. It is also possible to enhance the NOx suppression effect by preventing the additional combustion air E from flowing into the reduction combustion zone F. The first combustion exhaust gas D1 after complete combustion is incinerated ash A
The incinerated ash A is preheated by contact with the first exhaust gas pipe 12.
It is discharged from A. On the other hand, the slag cooling chamber 6 also has a second
The exhaust gas pipe 12B is connected, and the '/8 catalytic slag B is discharged from the melting chamber 8 together with a part of the second combustion exhaust gas D2 of the combustion exhaust gas, and the molten slag B is de-slagged by this second combustion exhaust gas D2. It is constructed so that it does not solidify and adhere to the outlet 5 and block it.

An exhaust gas adjustment damper 14 is provided in the second exhaust gas pipe 12B.
is intervened to adjust the flow rate of the second combustion exhaust gas D2,
The air is combined into one and introduced into the air preheater 15. An air supply pipe 17 connected to the discharge side of the air fan 16 is connected to the melting burner 2 via an air preheater 15. An additional air supply pipe 18 is branched from the air supply pipe 17 downstream of the air preheater 14 and connected to the additional air nozzle 11 . An air adjustment damper 19 is disposed in this additional air pipe 18.

Next, the effect will be explained.

The incinerated ash A supplied from the ash hopper 4 to the ash input port 3 is transferred to the preheating chamber 7 on the downstream side by the ash butcher device 9. The melting burner 2 in the melting chamber 8 is combusted in a state close to the stoichiometric air ratio, and the first combustion exhaust gas D1, which occupies most of the combustion exhaust gases D1 and D2, is introduced into the preheating chamber 7. This first
The combustion exhaust gas D1 is reductively combusted by being supplied with secondary fuel from the secondary fuel nozzle 10 in the reductive combustion region F, and most of the NOx is reduced. Furthermore, additional combustion air E is supplied from the additional air nozzle 12 in the complete combustion region G, and the combustible matter is completely combusted. Therefore, the amount of NOx generated can be significantly reduced, and combustible components that cause burnout of the air preheater 15 and air pollution can be removed. Furthermore, this first
The combustion exhaust gas D1 comes into contact with the incinerated ash A as a countercurrent, and after sufficiently preheating the incinerated ash A, is discharged from the first exhaust gas pipe 12A. 1300℃ by 7B melting burner 2 in melting chamber 8
Incineration ash A burned at a higher temperature becomes molten slag B,
The slag is sent from the slag outlet 5 to the slag cooling chamber 6 together with the second combustion exhaust gas D2, which is a part of the combustion exhaust gas. Here, the second combustion exhaust gas D2 prevents the molten slag B from heating and solidifying, thereby preventing the slag extraction port 5 from being blocked. Further, the combustion exhaust gases DI and D2 discharged from the first and second exhaust gas pipes 12A and 12B are transferred to the air preheater 14.
After heating the combustion air C, it is discharged to the atmosphere.

According to the above embodiment, the melting burner 2 is combusted with a theoretical amount of air to quickly melt the incinerated ash A at high temperature, and the secondary fuel is supplied into the first combustion exhaust gas D1 that is the subsequent flow to perform reductive combustion. A three-stage combustion is carried out in the preheating chamber 7 in which most of the generated NOx is reduced, and additional air is supplied downstream to completely burn the combustible matter, and the heat from these combustions and the first combustion are Since the exhaust gas D1 is brought into contact with the incinerated ash A in a counterflow to perform preheating, the amount of heat supplied by the melting burner 2 in the melting chamber 7 is small, and running costs can be significantly reduced. Furthermore, NOx in exhaust gas emitted into the atmosphere
i can be significantly reduced, and air pollution can be prevented. Also the second
Since the combustion exhaust gas D2 is drawn together with the molten slag B from the slag outlet 5, the trouble of clogging the slag outlet 5 does not occur.

Effects of the Invention As described above, according to the present invention, the combustion exhaust gas of the melting burner in the fj melting chamber is drawn to the upstream preheating chamber, and after the secondary fuel is supplied from the secondary fuel nozzle, the upstream additional air is By supplying additional air from the nozzle and performing three-stage combustion,
It is possible to significantly suppress the amount of NOx generated, and
The incinerated ash can be effectively preheated by bringing the combustion exhaust gas into contact with the incinerated ash, and the amount of heat supplied to the melting burner can be reduced to enable highly efficient operation. Therefore, it is possible to significantly reduce running costs by reducing the amount of fuel in the melting burner, to prevent air pollution, and to prevent equipment burnout due to combustible components.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a melting furnace showing an embodiment of the present invention;
FIG. 2 is a schematic diagram of a conventional melting furnace. A... Incineration ash, B... Molten slag, Dl... First combustion exhaust gas, D2... Second combustion exhaust gas, E...
・Additional combustion air, F... Reduction combustion area, G... Complete combustion area, 1... Melting furnace, 2... 78 fusion burner, 4...
・Ash popper, 6...Slag cooling chamber, 7...Preheating chamber,
8... Melting chamber, 10... Secondary fuel nozzle, 11...
・Additional air nozzle, 12A...first exhaust gas pipe, 12
B...Second exhaust gas pipe, 13...Partition wall, 18...
Additional air supply pipe.

Claims (1)

[Claims] 1. In an incinerated ash melting processing device that is equipped with a melting burner in the melting chamber of the melting furnace, the incinerated ash is melted by the melting burner, and the molten slag is discharged into the slag cooling chamber on the downstream side of the melting chamber. A secondary fuel nozzle for supplying secondary fuel is provided on the wall surface, an additional air nozzle is provided on the wall surface upstream of the secondary fuel nozzle, and a combustion exhaust gas pipe is connected to the wall surface upstream of the additional air nozzle. Incineration ash melting processing equipment.