JPH10146575A - Manufacture of fine fused spherical material from incineration ash of sludge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change incineration ash of sludge into a resource. SOLUTION: A manufacturing process of the fused spherical material of incineration ash is incorporated into a fluidized incineration system of sludge. Incineration ash is separated and recovered from exhaust gas of a fluidized incinerator A in a cyclone and introduced into a feeder 12 and sent into a burner 11 provided in a fused spherical material-producing furnace D together with carrier gas and ejected into flame of the burner 11. Incineration ash is melted and sphered. The molten sphered material is cooled by fluidization incineration exhaust gas and cooling air in accordance with necessity and sent to a cyclone E and fine fused spherical material is separated and recovered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a molten spheroid finer than an incinerated ash of sludge, in which a molten spheroid is produced in a fluidized incineration process of sludge so as to utilize sludge as a resource. It is about.

[0002]

2. Description of the Related Art In recent years, the incineration ash discharged by fluidized incineration of sewage sludge has increased considerably, and the effective use of incineration ash has become an essential condition due to the absolute shortage of the final disposal site residual capacity. ing. However, since fluidized incineration ash is difficult to use by itself, conventionally, it has been attempted to further use the molten incineration ash as a solid slag, or to effectively use it as a brick by firing.

[0003]

In the case of the above-mentioned incineration ash melting treatment, pebbles or fine sand-like slags are often taken out, and these slags are not high in strength. Adjustment of the particle size and fine pulverization are required, resulting in high cost.

The present invention has been made in view of the above-mentioned conventional circumstances, and a process for producing a fine molten spheroidized material having high possibility of being effectively used for cement or the like from incineration ash is referred to as a fluidized incineration process. The purpose of the present invention is to provide a new combined manufacturing method and promote the effective use of incinerated ash.

[0005]

The structure of the present invention for achieving the above object will be described with reference to the drawings corresponding to the embodiments. The present invention relates to a fluidized incinerator A for incinerating sludge. The incinerated ash collected from the exhaust gas through a collecting device such as cyclone C is removed together with the carrier gas 13 into L
After being sent into and blown out of an oxygen-enriched burner flame using PG gas as a fuel, each fine particle of incinerated ash is melted and spheroidized,
The flue gas from the fluidized incinerator A is directly used for cooling to produce solidified molten spheroids while floating, and the subsequent cyclone E
And the like, wherein the molten spheroidized product is separated and recovered.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a process suitable for carrying out the present invention, and FIG. 2 is a longitudinal sectional view showing a main part of a furnace for producing a molten spheroid in the process. FIGS. 3 and 4 show an example of a process which is different from the device for collecting the incinerated ash and the molten spheroid.

In FIG. 1, reference numeral A denotes a conventionally known fluidized incinerator, which is provided with a combustion chamber 2 provided with a burner 1 at a lower portion, and sludge is supplied to an intermediate portion of the fluidized incinerator A by a sludge supply pipe 3. The introduced sludge is incinerated in the furnace, and the exhaust gas including the generated incineration ash (hereinafter referred to as incineration ash gas) is discharged from the upper part of the fluidized incinerator A to the discharge duct 4.

The discharged incinerated ash gas flows into an exhaust gas heat recovery device B. The heat recovery apparatus B includes a combustion air preheater 6 for the fluidized incinerator A and an air preheater 7 for whitening protection. The incineration ash gas after heat recovery in this device B flows from the discharge duct 5 into the incineration ash cyclone C provided in the next stage, where it is separated into solid and gas, and the incineration ash exits from the lower part and exits from the ash hopper 10. The exhaust gas charged, stored, and separated from the tank flows out from the upper part into a discharge duct 23, and is separately supplied to a molten spheroidization furnace D provided next.

A burner 11 for melt spheroidization is connected to the upper part of the melt spheroidization furnace D toward the furnace. As shown in FIG. 2, the burner 11 uses incinerated ash that has been injected and blown out from the center by a carrier gas of compressed air, uses LPG gas as fuel, and converts oxygen-enriched air (oxygen content 30 to 99%) into oxygen. It is a burner that can be instantaneously melted in gas by passing it through a high-temperature flame of 1300 to 2500 ° C as a source.

[0010] The molten spheroid production furnace D is formed in a closed vertical cylindrical shape, and a lower end portion thereof is provided with a discharge hole 18 for a combustion gas containing a molten spheroid of the generated incineration ash. In addition, in the upper and lower middle part, an air supply hole 19a for blowing fluidized incinerator exhaust gas as a cooling gas into the furnace is provided connected to the duct 23, and an air supply hole 19b for blowing cooling air is provided. Is provided.

[0011] Incineration ash supplied to the furnace D for producing molten spheroids
20 is sent from the ash hopper 10 to the feeder 12, where it is mixed with the carrier gas 13 and sent to the raw material supply path 15 of the burner 11. At the same time, the fuel gas supply path 16 of the burner 11
The PG gas 22 also has oxygen-enriched air 21
Are respectively sent and burnt, and the flame 22 is ejected from the combustion chamber 14 into the furnace. Then, the combustion chamber 14 is supplied from the raw material supply path 15.
The incineration ash injected into the inside is melted by the flame 22. Thereafter, the fluidized incineration exhaust gas and, if necessary, cooling air are cooled and solidified during suspension to produce a fine molten spheroidized product. Also, as indicated by a chain line in the middle of the duct 23,
By installing a dry-type back filter 24, the recovery rate of incinerated ash can be increased. At this time, cooling air 26 may be introduced to lower the inlet temperature to the back filter 24.

The melting conditions of the incinerated ash include a flame temperature of 1,
Hold at 300-2,500 ° C to reduce the oxygen content of the oxygen-enriched air.
30-100%, fuel and incineration ash ratio is 2-50kg LPG / kg
The range is incinerated ash.

A cyclone E for recovering the spheroid is provided downstream of the melting spheroid production furnace D to collect the generated spheroid. If the gas separated by the cyclone E still contains fine molten spheroids, this is collected by the bag filter 25. that time,
Cooling air 27 to reduce the inlet temperature to bag filter 25
May be introduced.

FIG. 3 shows that the incineration ash recovery cyclone C is disposed immediately after the fluidized incinerator A, and the molten spheroid production furnace D is disposed immediately thereafter, followed by the molten spheroid recovery cyclone E. It is another process example. In this example,
There is an advantage that the scattering of the duct to the heat recovery device can be prevented.

FIG. 4 shows still another example of the process in which the cyclone E for recovering the molten spheroidized product is disposed after the heat recovery device.
In this example, there is a merit for preventing the heat recovery device from being blocked by the fine particles when there are many fine particles.

[0016]

As described above, according to the present invention,
The incineration ash melt spheroidization process is incorporated into the sludge fluidized incineration system to enable the incineration ash from the fluidized incinerator to be collected as fine molten spheroids. The ash can be recycled.
In addition, the resulting fine melt spheroids do not require a conventional pulverization step, and can be used directly as a cement substitute.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment of the present invention.

FIG. 2 is a vertical sectional view of a furnace for producing a molten spheroid used in the present invention.

FIG. 3 is a process chart showing another embodiment of the present invention.

FIG. 4 is a process chart showing still another embodiment.

[Explanation of symbols]

 Reference Signs List A Fluidized incinerator B Exhaust gas heat recovery device C Incinerated ash cyclone D Melted spheroidized product furnace E Cyclone for molten spheroidized product 6 Combustion air preheater 7 Preventive air preheater 8 Ash hopper 11 Melting spheroidizing burner 12 Incineration ash supply machine 13 Carrier gas 14 Combustion chamber 15 Raw material supply path 16 Fuel gas supply path 17 Oxygen supply path 18 Discharge holes 19a, 19b Air supply hole 20 Incineration ash 21 Oxygen-enriched air 22 LPG gas 23 Fluidized incinerator exhaust gas 24 Incinerated ash bag filter 25 Melted spheroid bag filter 26, 27 Cooling air

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Mitsucho Matsukawa 3-1-4 Motomachi, Naniwa-ku, Osaka-shi Kubota Namba Motomachi Office (72) Inventor Yasushi Chida 1-3-5 Matsugaya, Taito-ku, Tokyo 1-3-5 No. Kubota Environmental Service Co., Ltd.

Claims (1)

[Claims] The incinerated ash recovered from the exhaust gas from the fluidized incinerator that incinerates the sludge through a collection device such as a cyclone is sent and ejected together with the carrier gas into an oxygen-enriched burner flame using LPG gas as fuel. After melting and spheroidizing the fine particles of the incineration ash, it is cooled directly by using the exhaust gas of the fluidized incinerator to produce a solidified molten spheroidized substance while floating. A method for producing a finely-melted spheroidized substance from incinerated ash of sludge, comprising separating and recovering the oxidized substance.