TW202409493A - Waste treatment equipment and treatment methods - Google Patents

Abstract

[Topic] Prevent the decrease of the heat of the combustible gas obtained by gasifying the waste and suppress the odor countermeasure to the minimum. [Solution] A waste treatment device 1 comprises: a drying device 6 for drying the waste (crushed material) W5; a gasifier 8 for heating the dried material discharged from the drying device by using the preheated raw material R1 taken out from the preheating cyclone (lowest cyclone) 31 of the cement burning device 30 to gasify it; and a combustible gas supply device for supplying the combustible gas G1 generated in the gasifier to the calcining furnace 33 or cement kiln 32 of the cement burning device. The slag S generated in the gasifier can also be introduced into the drying device and used for drying the waste. The outlet temperature of the gasifier can also be controlled so that the outlet temperature of the drying device becomes higher than a predetermined value.

Description

Waste treatment device and method

Invention Field

The present invention relates to a waste processing device and a processing method, and in particular to a device and method for effectively utilizing combustible waste with a high moisture content or waste containing combustible components as fuel for a cement burning device.

Invention Background

In the past, attempts have been made to use highly water-containing combustible waste such as municipal garbage and sludge as an alternative fuel in cement manufacturing to promote waste treatment and reduce the unit consumption of expensive fossil fuels in cement manufacturing.

For example, Patent Documents 1 and 2 describe a waste treatment facility that includes: a gasifier that gasifies waste including sludge, etc.; and a gas transport path that directly transports the combustible gas generated by the gasifier containing coke and ash to a calcining furnace of a cement manufacturing facility, etc. Prior Art Documents Patent Documents

Patent Document 1: Japanese Patent Publication No. 2013-540051 Patent Document 2: Japanese Patent Publication No. 2014-500840

Summary of the invention The problem to be solved by the invention

However, in the inventions described in the above-mentioned Patent Documents 1 and 2, there has been a problem in the past that the calorific value of the combustible gas generated in the gasifier is reduced due to the moisture contained in the fluidized air and waste supplied to the gasifier.

Furthermore, the above-mentioned Patent Document 1 describes installing a drying device in the front stage of the gasification furnace. However, there is also a problem that when hot air is used to dry waste, large-scale odor measures must be taken depending on the type of waste.

Therefore, the present invention was made in view of the above-mentioned problems of the conventional technology, and its object is to provide a waste processing device and a processing method that can prevent the heat of the flammable gas obtained by gasifying waste from decreasing. And suppress odor countermeasures to a minimum. means of solving problems

To achieve the above-mentioned purpose, the present invention is a waste treatment device, which is characterized by comprising: a drying device for drying the waste; a gasifier for heating the dried material discharged from the drying device by using the preheated raw material separated from the preheating cyclone of the cement burning device to gasify it; and a combustible gas supply device for supplying the combustible gas generated in the gasifier to the calcining furnace or cement kiln of the aforementioned cement burning device.

According to the present invention, after the waste is dried, fluidized air is not used, but preheated raw materials separated from the preheating cyclone of the cement burning device are used for heating and gasification, thereby preventing the heat of the combustible gas generated in the gasifier from decreasing.

In the waste treatment apparatus, the slag generated in the gasifier is introduced into the drying device to dry the waste, so that large-scale odor countermeasures such as hot air drying are not required.

Furthermore, by controlling the outlet temperature of the aforementioned gasifier so that the outlet temperature of the aforementioned drying device becomes above a predetermined value, the moisture content of the dried product can be adjusted to below a predetermined value, and the outlet temperature of the aforementioned gasifier can be controlled by the amount of preheated raw material separated from the preheating cyclone of the aforementioned cement burning device.

Furthermore, the preheated raw material can be separated from the discharge of the drying device, introduced into a cement kiln of the cement burning device, and used as a cement raw material.

Furthermore, the present invention is a waste processing method characterized by drying the waste, using preheated raw materials separated from the preheating cyclone of the cement burning device, and drying the dried product obtained by the drying. Heating is performed to gasify, and the combustible gas obtained by the gasification is supplied to the calcining furnace or cement kiln of the cement burning device.

According to the present invention, similar to the above-mentioned invention, since fluidized air or the like is not used but a preheated raw material is used to heat and vaporize, it is possible to prevent the heat of the generated flammable gas from being reduced.

In the above waste treatment method, the residue produced by the above-mentioned gasification is used for drying the waste, thereby enabling odor treatment to be performed in a small-scale device compared to hot air drying.

Furthermore, the preheated raw material can be separated from the mixture of the dried product of the dried waste and the residue used for drying, and can be introduced into a cement kiln of the cement burning device and used as a cement raw material. Invention effect

As described above, according to the present invention, it is possible to prevent the heat loss of the combustible gas obtained by gasifying waste from being reduced, and to minimize odor countermeasures.

Detailed description of preferred embodiments Next, the form used to implement the present invention is described in detail with reference to the drawings.

FIG. 1 shows an embodiment of a waste treatment device (hereinafter referred to as “treatment device”) of the present invention. The treatment device 1 is provided in a cement burning device 30 to treat urban waste W1 discharged from a waste treatment plant 20 .

The processing device 1 is equipped with: a magnetic separator 2 that removes magnetic metals such as iron flakes I from the municipal garbage W1; an electrostatic separator 3 that removes aluminum Al from the municipal waste W2 after removing the iron flakes I; A specific gravity separator 4 for removing other metals M from municipal waste W3; a crusher 5 for crushing municipal waste W4 discharged from the specific gravity separator 4; a drying device 6 for drying the crushed material W5 discharged from the crusher 5; for drying The dried material D discharged from the device 6 is sorted by a vibrating screen 7; and a gasifier 8 is used to heat and gasify the dried material W6 of the waste separated by the vibrating screen 7.

The magnetic separator 2, the electrostatic separator 3 and the gravity separator 4 are devices generally used for waste treatment, and may be other devices as long as they can remove various metals from the urban garbage W1. In addition, the crusher 5 may be unnecessary depending on the properties of the urban garbage W4 discharged from the gravity separator 4.

The drying device 6 is provided to dry the crushed material W5 from the crusher 5 using the slag S produced in the gasifier 8, and the crushed material W5 is dried using the slag S as a solid heat medium in a powdery or granular form, so that large-scale odor countermeasures such as when drying using hot air are not required. The exhaust gas G2 from the drying device 6 is introduced into the outlet exhaust duct of the lowest stage cyclone 31 of the cement burning device 30.

The vibrating screen 7 is configured to sort the dried material (the mixture of the dried material of the waste and the residue S of the gasifier 8) D discharged from the drying device 6 into the dried material of the waste W6 and the preheated raw material R2.

The gasification furnace 8 is configured to use the preheated raw material R1 taken out from the raw material chute 34 of the lowermost cyclone 31 of the preheater of the cement burning device 30 on the screw conveyor 35, and convert the dried waste W6 into Heat to vaporize. The combustible gas G1 generated in the gasification furnace 8 is supplied to the calcining furnace 33 via a combustible gas supply device (not shown).

In the cement burning device 30, a screw conveyor 35 for separating the preheated raw material R1 is arranged in the raw material chute 34 of the lowest stage cyclone 31. The screw conveyor 35 has an opening from which the upper half of the shell is removed, and the preheated raw material R1 is separated from the opening and introduced into the gasifier 8.

Next, the waste processing method of the present invention using the processing device 1 having the above-mentioned structure will be described with reference to FIG. 1 .

Various metals (iron pieces I, aluminum Al, and other metals M) are removed from the urban garbage W1 by the magnetic separator 2, the electrostatic separator 3, and the specific gravity separator 4, and the urban garbage W4 is crushed by the crusher 5. The crushed material W5 is dried using the slag S of the gasifier 8 in the drying device 6. In addition, the preheated raw material R1 taken out from the lowest cyclone 31 of the cement burning device 30 can be used for drying during the initial operation.

The dried matter D discharged from the drying device 6 is separated into the waste dried matter W6 and the preheated raw material R2 in the vibrating screen 7. The dried matter W6 is supplied to the gasifier 8, and the preheated raw material R2 is introduced into the cement kiln 32 or the cement raw material system and utilized as cement raw material.

The preheated raw material R1 taken out from the lowest cyclone 31 of the cement burning device 30 is used in the gasifier 8 to heat the waste dried material W6 for gasification, and the combustible gas G1 generated by the gasification is supplied to the calcining furnace 33 through the combustible gas supply device (not shown) and used as fuel. At this time, it can also be introduced into the existing calcining furnace burner 33a, or it can be blown into the calcining furnace 33 from a dedicated nozzle set separately. On the other hand, the slag S of the gasifier 8 is sent back to the drying device 6 for drying.

In the above embodiment, if the exhaust gas G2 containing water vapor discharged from the drying device 6 has an odor, it is introduced to the outlet exhaust duct of the lowermost cyclone 31 of the cement burning device 30. If there is no odor, it is introduced to the outlet of the cyclone 31. The preheating cyclone above the lowermost cyclone 31 or the exhaust guide fan at the rear stage of the preheater is processed.

The outlet temperature of the drying device 6 (the temperature of the dried material D discharged from the drying device 6) is controlled above 100°C, preferably above 120°C, so that the moisture content of the dried material D is below the target value. By controlling the gasification furnace 8 to adjust the outlet temperature of the drying device 6. The outlet temperature of the gasification furnace 8 is controlled at about 520°C. Alternatively, cascade control for controlling the amount of the preheated raw material R1 may be performed so that the outlet temperature of the gasifier 8 reaches a predetermined target value. Furthermore, in order to adjust the outlet temperature of the drying device 6 , the preheated raw material R1 may be added to the residue S of the gasification furnace 8 .

Furthermore, in the above-mentioned embodiment, although the preheated raw material R1 from the lowermost cyclone 31 is used as the heat medium in the gasification furnace 8, the preheated material R1 located above the lowermost cyclone 31 may also be used. The preheated raw materials separated by the cyclone.

Furthermore, although the combustible gas G1 generated in the gasifier 8 is supplied to the calciner 33 and utilized as fuel, it may also be supplied to the cement kiln 32 and utilized as fuel. In this case, the combustible gas G1 may be introduced into the cement kiln burner, or may be blown into the cement kiln from a dedicated nozzle or the like provided separately from the cement kiln burner. Any combustible gas supply device may be used as long as it can supply the combustible gas G1 from the front of the cement kiln into the cement kiln.

Furthermore, the embodiments shown in the drawings are merely illustrative and are not intended to limit the technical scope of the present invention.

1: Processing device 2: Magnetic separator 3:Electrostatic separator 4: Specific gravity sorting machine 5: Crusher 6:Drying device 7: Vibrating screen 8:Gasifier 20:Garbage disposal site 30: Cement burning device 31: The lowermost cyclone 32:Cement kiln 33:Calcining furnace 33a: Calciner burner 34: Raw material chute 35:Screw conveyor Al: aluminum D: dry matter G1: flammable gas G2: exhaust I:iron piece M: metal R1: Preheat raw materials R2: Preheat raw materials S: residue W1: Urban garbage W2: Urban garbage W3: Urban waste W4: Urban waste W5: Waste (broken materials) W6: Dry matter

FIG. 1 is an overall block diagram showing an embodiment of the waste processing device of the present invention.

1: Processing device

2: Magnetic separator

3:Electrostatic separator

4: Specific gravity sorting machine

5: Crusher

6: Drying device

7: Vibration screen

8: Gasification furnace

20: Garbage disposal site

30: Cement burning device

31: The lowermost cyclone

32:Cement kiln

33:Calcining furnace

33a: Calciner burner

34: Raw material chute

35:Screw conveyor

Al: Aluminum

D: Dry matter

G1: flammable gas

G2: exhaust

I:iron piece

M: metal

R1: Preheat raw materials

R2: Preheat the raw materials

S: residue

W1: Urban garbage

W2: Urban waste

W3: Urban waste

W4: Urban waste

W5: Waste (broken materials)

W6: Dry matter

Claims (8)

A waste processing device is characterized by having: Drying device to dry the waste; The gasification furnace uses the preheated raw material separated from the preheating cyclone of the cement burning device to heat and gasify the dry matter discharged from the drying device; and The combustible gas supply device supplies the combustible gas generated in the gasification furnace to the calcining furnace or cement kiln of the cement burning device. A waste processing device according to claim 1, which introduces the residue generated in the gasification furnace into the drying device and uses it for drying the waste. For example, the waste treatment device of claim 1 or 2 controls the outlet temperature of the gasification furnace so that the outlet temperature of the drying device becomes above a predetermined value. For example, the waste treatment device of claim 1, 2 or 3 controls the outlet temperature of the gasification furnace by the amount of preheated raw material separated from the preheating cyclone of the cement burning device. For example, the waste treatment device of claim 2, 3 or 4 separates the preheated raw material from the discharge of the drying device and introduces it to the cement kiln of the cement burning device. A method of treating waste is to dry the waste, use preheated raw materials separated from the preheating cyclone of the cement burning device, heat and gasify the dried material obtained by the drying, and vaporize the waste. The combustible gas obtained by this gasification is supplied to the calcining furnace or cement kiln of the cement burning device. The waste treatment method of claim 6, wherein the residue produced by the gasification is used for drying the waste. The waste treatment method of Claim 7 separates the preheated raw material from the mixture of the dried waste and the residue used for drying, and introduces it into the cement kiln of the cement burning device.

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