JPH05322145A - Fluidized bed type incinerator - Google Patents

Abstract

PURPOSE:To enable salts within material to be burned to improve durability of a fluidized bed type incinerator. CONSTITUTION:A furnace main body 1 is provided with a supplying port 2 for use in feeding materials to be buned and a discharging port for use in discharging dust after ignition. To the discharging port 3 are connected in sequence through a cyclone 4, an air preheater 5, a bag filter 6 and a discharging gas outlet 7. A discharging port 9 of a hopper 8 for feeding the materials is arranged near the supplying port 2. A heating air transfer pipe 10 is arranged within the furnace main body 1 and ceramic sand 11 are stored while the air transfer pipe 10 being buried. The ceramic sand 11 are hollow particles of ceramic having superior heat-resistant characteristics with a diameters of 1mm to 4mm and have small specific gravities, so that they float on water surface. The furnace main body 1 is provided with a burner 12, a heavy oil supplying device 13 and an oxygen supplying device 14. The inner side of the furnace main body 1 can be heated up to 1400 to 1500 deg.C of a boiling point of NaCl, and there is provided a vacuum pump 15 for reducing the pressure in the furnace main body 1 and further reducing the boiling points of the salts inside the furnace and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed incinerator.

[0002]

2. Description of the Related Art In an incinerator, a fluidized bed is used in which air is blown into the incinerator from below to fluidize heated silica sand and decompose and burn the suspended matter while suspending the incinerated matter. Incinerators are known. In this fluidized bed incinerator, there are no mechanically movable parts inside the furnace body, so there are few failures, and since the heat storage amount of silica sand is large, stable operation is possible even if there is some variation in the properties of the incinerator. , Even if you stop at night, there is a merit that the startup is fast.

Therefore, if the silica sand is made to flow around 800 degrees inside the furnace body, the incineration process can be carried out efficiently regardless of the type of material to be incinerated. It has been widely used to incinerate industrial waste.

[0004]

However, in the above conventional fluidized bed incinerator, the material to be incinerated is a substance containing salts represented by NaCl, or the material to be incinerated contains salt. If these are to be incinerated under normal operating conditions, salts will melt in the furnace body and the molten salts will adhere to the inner wall of the furnace body. When silica sand adheres to the inside of the furnace body as described above, the sand particles are more and more adsorbed to each other and the furnace body fails to function. On the other hand, when operating at a high temperature where internal salts evaporate, there is a problem that not only silica sand but also the furnace body cannot withstand heat and durability is reduced.

Therefore, according to the present invention, even if the incineration object is a substance containing salts, or the incineration object contains salt, it can be incinerated reliably and the durability of the furnace body etc. can be improved. It provides an incinerator.

[0006]

Means for Solving the Problems A furnace main body for accommodating sandy granules, an air supply pipe for heating sandy granules, a supply port for injecting an object to be incinerated, and discharging dust after incineration In a fluidized bed incinerator having a discharge port, the sand-like particles are formed of a hollow heat-resistant material. Further, the furnace main body may be provided with an internal salt evaporating means for evaporating the salt content in the incineration object, and the furnace main body may be formed of a heat-resistant material that can withstand the internal salt evaporation temperature of the incineration object. Further, a pressure reducing means for reducing the pressure in the furnace body may be provided.

[0007]

[Operation] When the incinerator is put into the furnace body and heated air is supplied from the air supply pipe to the sand-like particles in the furnace body,
The incinerator is decomposed and burned by the flowing sand-like particles. Here, when the incinerator contains salts, the molten salts adhere to the inside of the furnace body, but the sand-like particles formed in the hollow and having a large volume are It is less likely to adhere to the molten salts on the inner wall of the furnace body than the granules. further,
By evaporating the contained salt content that has been melted by the internal salt evaporating means, the adhesion of the sand-like particles within the furnace body is prevented.
At this time, the furnace body is made of a heat-resistant material that can withstand the internal salt evaporation temperature to ensure durability. Then, if the pressure inside the furnace main body is reduced by the pressure reducing means, the internal salt evaporation temperature is lowered, and the evaporation of the internal salts can be accelerated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIG.

The furnace body 1 is provided with a supply port 2 through which an incineration object is put.
And a discharge port 3 in the upper part of the furnace body 1 for discharging dust after incineration. An air preheater 5 is connected to the discharge port 3 via a cyclone 4, and the air preheater 5 has a bag filter 6
The exhaust gas outlet 7 is connected via. A discharge port 9 of a hopper 8 for the incineration object is provided at the supply port 2 in advance.

Inside the furnace body 1, an air supply pipe 10 for heated air is provided.
The air supply pipe 10 is buried and the ceramic sand 11 as sand-like particles is housed in the furnace body 1. Here, a hole 10A is formed downward in the air supply pipe 10, and heated air is sent out to the ceramic sand 11 from here. In addition, a part of the air supply pipe 10 is connected to the air preheater 5. Here, the ceramic sand 11 is made of alumina ceramic particles having a diameter of 1 mm to 4 mm and is formed in a hollow shape, and has a specific gravity that floats on water.

The furnace body 1 is provided with a burner 12 as an internal salt evaporating means, a heavy oil supply device 13 and an oxygen supply device 14.

The burner 12 directly heats the inside of the furnace body 1, the heavy oil supply device 13 directly heats the inside of the furnace body 1 by combustion of the heavy oil, and the oxygen supply device 14 causes the furnace body 1 to heat. The inside of the furnace body 1 is heated to a high temperature to evaporate the internal salts of the material to be incinerated.

By the burner 12, the heavy oil supply device 13, the oxygen supply device 14, or any one of them, the internal salt evaporation temperature of the substance to be incinerated, that is, 1400 which is the boiling point of NaCl 1500
It can be heated every time.

The wall surface of the furnace body 1 is formed of a heat-resistant castable material containing at least the boiling point of the internal salt, for example, a heat-resistant castable material containing alumina ceramic as a main component.

Further, the furnace body 1 is provided with a vacuum pump 15 as a pressure reducing means for lowering the pressure in the furnace body 1 to lower the boiling point of the internal salts. Therefore, the furnace body 1 is a pressure vessel that can withstand the pressure drop by the vacuum pump 15. In FIG. 1, A indicates combustion air and B indicates burned gas.

According to the structure of the above-described embodiment, when the material to be incinerated is fed into the furnace body 1 through the supply port 2 and the heated air is supplied from the air supply pipe 10 to the ceramic sand 11 inside the furnace body 1, The inside of the main body 1 is maintained in a normal operating state of about 800 degrees, and the incineration object is decomposed and burned by the flowing ceramic sand 11.

At this time, since the ceramic sand 11 is formed in a hollow shape and has a large volume, it is advantageous in that it is less likely to adhere to the molten salt than the conventional silica sand having a small particle size.

Further, since the ceramic sand 11 is formed in a hollow shape, the volume increases but the weight does not increase, and therefore the fluidity is not adversely affected.

Here, when the incinerated matter contains salts, a sensor (not shown) detects this salt content,
The burner 12, heavy oil supply device 13, oxygen supply device 14
Are appropriately operated to raise the operating temperature of the furnace body 1 from 1400, which is the boiling temperature of salts, to 1500 ° C.
The inside is maintained at the special operating temperature for a predetermined time.

If necessary, the vacuum pump 15 keeps the inside of the furnace body 1 in a negative pressure state, while oxygen is supplied by the oxygen supply device 14, the boiling point of salts is lowered to accelerate the evaporation of salts.

Therefore, since the salts that only melt at the normal operating temperature are vaporized at the special operating temperature, the salts can be prevented from adhering to the inside of the furnace body 1 and continuous operation can be performed, and the durability of the apparatus can be improved. Can be improved.

Here, the furnace body 1 is exposed to a large thermal load due to a special operating temperature, but since the furnace body 1 is protected by a heat-resistant material that can withstand at least the evaporation temperature of salts, there is no problem regarding heat resistance. ..

When the material to be incinerated is burned in the furnace body 1 in this way, combustion gas and dust are sent from the discharge port 3 to the cyclone 4 to remove dust of 10 microns or more, and further by the air preheater 5. The amount of heat to be reused is recovered, dust of 2 microns or more is removed by the bag filter 6, and after various treatments, it is discharged from the exhaust gas outlet 7 to the outside of the machine.

[0024]

As described above, according to the invention described in claim 1, since the sandy granular material is formed in a hollow shape and has a large volume, it is smaller than the conventional silica sand having a small particle diameter. It is advantageous in that it is less likely to adhere to the molten salts, and the volume increases but the weight does not increase, and therefore the fluidity is not adversely affected.

According to the invention described in claim 2,
Further, by providing an internal salt evaporation means, for example, it is possible to evaporate the salt contained in the incineration,
The sand-like particles do not adhere to the molten salts on the inner wall of the furnace body, and the function of the furnace body can be properly maintained.

Further, according to the invention described in claim 3, since the pressure reducing means for lowering the pressure in the furnace body is further provided, the temperature of the evaporation of the internal salts can be lowered, and accordingly, the internal temperature can be lowered. The evaporation of salts can be accelerated.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Furnace main body 2 ... Supply port 3 ... Exhaust port 10 ... Air supply pipe 11 ... Ceramic sand (sandy granular material) 12 ... Burner (internal salt evaporation means) 13 ... Heavy oil supply means (internal salt evaporation means) 14 ... Oxygen supply Means (Internal salt evaporation means) 15 ... Vacuum pump (Decompression means)

Claims (3)

[Claims] 1. A furnace main body for accommodating sandy granules, an air supply pipe for heating the sandy granules, a supply port for introducing an incineration object, and an exhaust port for discharging dust after incineration. In a fluidized bed incinerator, the sandy granules are formed of a hollow heat-resistant material. 2. A furnace main body for accommodating sandy particles, an air supply pipe for heating the sandy particles, a supply port for injecting an incineration object, and an exhaust port for discharging dust after incineration. In a fluidized bed incinerator equipped with, the sand-like particles are formed of a hollow heat-resistant material, the furnace body is provided with an internal salt evaporation means for evaporating the salt in the incineration object, and the furnace body is incinerated A fluidized bed incinerator characterized by being formed of a heat-resistant material capable of withstanding the salt evaporation temperature inside a substance. 3. A furnace main body for accommodating sand-like particles, an air supply pipe for heating the sand-like particles, a supply port for introducing an incineration object, and an exhaust port for discharging dust after incineration. In a fluidized bed incinerator equipped with, the sand-like particles are formed of a hollow heat-resistant material, the furnace body is provided with an internal salt evaporation means for evaporating the salt in the incineration object, and the furnace body is incinerated A fluidized bed incinerator, which is formed of a heat-resistant material that can withstand the internal salt evaporation temperature and is provided with decompression means for reducing the pressure in the furnace body.