JPH10103639A - Pyrolysis reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a good sealing property of a sliding surface between a rotating side of a pyrolysis drum and a fixed side which does not rotate, and to prevent outside air from flowing into the drum. A pyrolysis reaction that pyrolyzes waste supplied into a rotating drum body by heated air to generate a pyrolysis gas and a pyrolysis residue, and discharges the pyrolysis gas and the pyrolysis residue. A jacket 1 provided in a vessel and filled with low-oxygen gas having an oxygen concentration of 5% or less outside a sliding surface 5b between a waste outlet rotary cylinder 26 and a non-rotating outlet fixed cylinder 35a.
2 is provided. Further, the sliding surface 5b may be provided outwardly to a position where the thermal effect inside the pyrolysis reactor is small, or a cooling water flow path for cooling the sliding surface 5b may be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pyrolysis reactor for thermally decomposing a substance to be thermally decomposed by a heat medium, and particularly to waste (general waste such as municipal waste from homes and offices,
Pyrolysis reactor that thermally decomposes waste plastic, car shredder dust, industrial waste such as waste office equipment, electronic equipment, and chemical products, etc.) using a heat medium and a waste treatment apparatus provided with the pyrolysis reactor It is about.

[0002]

2. Description of the Related Art Conventionally, as a device for heating a substance in a low oxygen atmosphere and dry distillation (pyrolysis), in addition to a vertical shaft type heating device having no driving portion, a device having a rotary drum structure (rotary). (Also known as a kiln). For example, as a pyrolysis reactor in a waste treatment apparatus, for example, old West German patents 3,723,187 and 3,067,771 and European Patent 0157330B1 are known. These wastes are supplied from the inlet, and the wastes are introduced into a drum body, which is a rotatable body by a screw conveyor or the like, and thermally decomposed while rotating the inside of the drum body. And a residue. The pyrolysis gas is discharged from the upper part of the discharge part adjacent to the drum body, and the pyrolysis residue is approximately 300 to 600 ° C., usually about 45 ° C.
It is discharged from the lower part of the discharge part at a temperature of 0 ° C. Here, in general, the inside of the drum body of the pyrolysis reactor is maintained at a pressure lower than the atmospheric pressure in a low oxygen atmosphere, and the friction on the sliding surface between the rotating drum body flange and the non-rotating fixed cylinder flange is maintained. In order to reduce this, a mechanism is provided for interposing and contacting grease with the sliding surface to seal the sliding surface.

[0003]

However, the conventional pyrolysis reactor merely contacts the sliding surface between the flange of the rotating drum main body and the flange of the non-rotating fixed cylinder with the interposition of grease. Therefore, external air may leak into the drum main body due to the mounting accuracy of the drum main body itself, the mounting accuracy of the flange, the unevenness of the surface finish, and the deformation due to heat. When the external air leaks into the drum main body, it adversely affects the low oxygen atmosphere inside the drum body, lowers the calorific value of the pyrolysis gas generated here, and is not preferable for the operation of the downstream combustion furnace.

Further, the temperature inside the drum body is generally about 45
Due to the high temperature of 0 ° C., the grease between the flanges may melt and flow out, or the grease may be excessively deteriorated, so that the sealing effect and lubricity may be reduced.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a sliding surface between an inlet side of a pyrolyzate of a pyrolysis reactor body and a fixed non-rotating inlet side, and a pyrolyzate of the body. An object of the present invention is to provide a pyrolysis reactor which has good sealing and lubricating properties of a sliding surface between an outlet side and an outlet fixed side which does not rotate, does not leak outside air, and a waste treatment apparatus provided with the same.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for thermally decomposing a thermally decomposed product supplied to a rotating body by using a heat medium, and comprises a thermal decomposition gas and a heat mainly composed of non-volatile components. In a pyrolysis reactor that generates a decomposition residue and discharges the pyrolysis gas and the pyrolysis residue, a sliding surface between the heat decomposition product inlet side of the body and a non-rotating inlet fixed side, and A sliding surface between at least one of a sliding surface of the fuselage and a fixed surface that does not rotate; and a low-oxygen seal between the sliding surface and the jacket. A low oxygen gas filling space filled with gas is provided. In the case where a low-oxygen gas-filled space filled with low-oxygen gas is provided between the sliding surface and the jacket, the external air does not directly enter the body of the thermal decomposition reactor, for example, the low-oxygen gas is Even if the gas enters the inside of the body, only the gas having a low oxygen concentration enters, and the body is maintained in a low oxygen atmosphere.

Further, in the above-mentioned pyrolysis reactor, the sliding surface is provided to be spaced outwardly to a position where the heat effect inside the pyrolysis reactor is small. In the case where the sliding surface is provided at a position outside the thermal decomposition reactor to a position where heat influence is small, specifically, a position where the temperature of the sliding surface is about 200 ° C. or less, the thermal decomposition reactor is used. In addition to the effect of the above, the temperature of the sliding surface is not increased, the outflow and excessive deterioration of the grease interposed on the sliding surface is prevented, and the sealing performance of the thermal decomposition reactor is maintained.

Further, in any one of the above-mentioned thermal decomposition reactors, a cooling water channel for cooling the sliding surface is provided. Those provided with a cooling water flow path for cooling the sliding surface,
In addition to the operation of any one of the above-mentioned thermal decomposition reactors, the temperature of the sliding surface and the seal portion can be made lower than the temperature at which grease flows out and deteriorates little.

[0009] In any one of the above pyrolysis reactors, the oxygen concentration of the low oxygen gas is 5% or less.
When the oxygen concentration of the low oxygen gas is 5% or less, the oxygen concentration is sufficiently low even if the low oxygen gas flows into the thermal decomposition reactor in addition to the operation of any of the above-mentioned pyrolysis reactors. Maintain a low oxygen atmosphere inside the fuselage.

[0010] Further, a pyrolysis reactor for pyrolyzing waste with a heat medium to generate a pyrolysis gas and a pyrolysis residue mainly composed of nonvolatile components, and the pyrolysis reactor discharged from the pyrolysis reactor. In a waste treatment apparatus having a separation device for separating a residue into a combustible component and a non-combustible component, and a combustion furnace for transferring and burning the pyrolysis gas and the combustible component, the pyrolysis reactor includes: By providing the thermal decomposition reactor described in any of the above, it is possible to improve waste treatment efficiency and maintenance.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a thermal decomposition reactor according to the present invention and a waste treatment apparatus provided with the same will be described in detail with reference to the drawings. In FIGS. 1 to 5, the same structures and working parts are denoted by the same reference numerals.

FIG. 4 is a system diagram showing an embodiment of the waste treatment apparatus according to the present invention, and FIG. 5 is a schematic longitudinal sectional view of a thermal decomposition reactor provided in the waste treatment apparatus of FIG. is there. In the waste treatment apparatus 1 of the present embodiment, the waste a such as municipal waste, which is a thermal decomposition product, is crushed into, for example, 150 mm square or less by a crusher such as a biaxial shearing type, and thermally decomposed by a conveyor or the like. It is charged into the reactor 2 and pyrolyzed to generate a pyrolysis gas G ₁ and a pyrolysis residue b. The pyrolysis reactor pyrolysis gas G ₁ and the pyrolysis residue b generated in 2 is separated is sent to the discharge unit 34, the pyrolysis gases G ₁ is the combustion furnace via the pyrolysis gas line L ₂ combustion It is supplied to the burner 42 of the melting furnace 41. The pyrolysis residue b varies depending on the type of the waste a. In the case of municipal solid waste, usually, most of the flammable components are relatively fine granules (10 to 60%) and the ash content of relatively fine granules (5 to
40%), coarse-grained metal components (7 to 50%), coarse-grained rubble, pottery, concrete pieces, and the like (10 to 60%).

The pyrolysis residue b having such components is 4
Since it is a relatively high temperature of about 50 ° C., it is cooled to about 80 ° C. by the cooling device 37, for example, a classifier such as a sieve,
It is supplied to a known single or combined separation device 38 such as a magnetic separation type, an eddy current type, a centrifugal type or a wind separation type, where the fine-grain combustible component c (including ash) and the coarse-grain non-combustible component and the non-combustible component d is collected in the container 39 and reused.

[0014] Then, the combustible component c in grinder 40, for example, 1mm milled below, it is supplied to the burner 42 of the burning melting furnace 41 through the combustible component line L _3.
The combustible component c, together with the supplied combustion air e from the combustion air line L ₄ by pyrolysis gas line L ₂ pyrolysis gas G ₁ a blower 45 supplied from 1,300
The ash contained in the combustible component c at this time becomes molten slag f, adheres to the inner wall of the combustion melting furnace 41, flows down, and flows from the bottom discharge port 43 to the water tank 44. It falls and becomes slag.

High temperature exhaust gas G generated in the combustion melting furnace 41
₂ is a flue gas line L ₅ through a heat exchanger (not shown).
From the waste heat boiler 47 to remove heat by a dust collector 49 and further remove harmful components from an exhaust gas purifier 50,
Is released from the chimney 52 into the atmosphere through the induced draft machine 51 is a low-temperature clean gas G ₃ in. Waste heat boiler 47
Is used for power generation by a generator 48 having a steam turbine. Clean part of the exhaust gas G ₃ are cooling device by a cooling gas line L ₆ via a fan 53 37
Supplied to

FIG. 5 is a schematic longitudinal sectional view of the thermal decomposition reactor 2 provided in the waste treatment apparatus 1 of FIG. The waste a charged into the charging section 31 of the pyrolysis reactor 2 is
Is supplied to the drum body 24 which is a body through a screw feeder 29 having a screw that rotates.
The inside of the drum main body 24 is maintained at a pressure lower than the atmospheric pressure in a low oxygen atmosphere, and leakage of the air is prevented by the seal portions 3 and 4.

The drum body 24 is inclined toward the outlet side of the waste a and sequentially rotates the waste a while rotating as shown in FIG.
It is a horizontal rotary type that moves to the right exit of Waste a is a heat medium supplied via the hot air line L ₁ is heated by the heat exchanger (not shown) disposed on the downstream side of the combustion melting furnace 41 in drum body within 24 heated air h to 300-600 ° C, usually 450 ° C
Heated to a degree. Therefore, the waste a is thermally decomposed, the thermal decomposition gas G _1, mainly the non-volatile pyrolysis residue b generated.

Here, the heated air h passes from the air inlet 36a to the air heating tube 28 in the drum main body 24 through the air inlet fixed chamber 35b and the air inlet rotating chamber 33a to heat the waste a. Thereafter, the air is discharged from the air outlet 36b through the air outlet rotation chamber 33b and the air outlet fixed chamber 30b. The air outlet rotation chamber 33b and the air outlet fixed chamber 30b through which the heated air h passes, and the air inlet rotation chamber 33a and the air inlet fixed chamber 3
5b is an inlet rotary cylinder 25 that rotates together with the drum main body 24.
And waste gas a and pyrolysis gas G
₁ and the inside of the drum where the pyrolysis residue b is present.

At this time, the air inlet rotating chamber 33a and the air outlet rotating chamber 33b, and the inlet rotating barrel 25 and the outlet rotating barrel 26 rotate together with the drum main body 24, but the air in which the air inlet 36a and the air outlet 36b are disposed. The inlet fixed chamber 35b and the air outlet fixed chamber 30b are fixed portions without rotating. Therefore, the air outlet rotation chamber 33b and the air outlet fixed chamber 30b, and the air outlet fixed chamber 30b and the inlet rotary cylinder 25 are sealed by the sliding surfaces 27a1 and 27a2, respectively.
The air inlet rotation chamber 33a and the air inlet fixed chamber 35b, and the air inlet fixed chamber 35b and the outlet rotary cylinder 26 are sealed by sliding surfaces 27b1 and 27b2, respectively.

[0020] On the other hand, a outlet fixed cylinder 35a which is the outer tube inlet fixed cylinder 30a, and the discharge portion 34 guides the pyrolysis residue b and pyrolysis gas G ₁ of the screw feeder 29 is fixed without rotating, thus, Sliding surfaces 5a and 5b are formed between the inlet rotary cylinder 25 and the outlet rotary cylinder 26 which rotate together with the drum main body 24, respectively. Between the inside of the drum where the waste a, the pyrolysis gas G ₁ and the pyrolysis residue b are present, and the outside air, these sliding surfaces 5 a and 5 b, and further, the sliding surfaces 5 a and 5
The seal is provided by the seal portions 3 and 4 provided on the drum b, and leakage of outside air into the drum main body 24 is reliably prevented.

FIG. 1 shows a first example of a pyrolysis reactor according to the present invention.
FIG. 5 is a cross-sectional view of a main part showing an embodiment, showing a seal portion 4 in FIG. 5. The seal portion 4 of the pyrolysis reactor according to the present embodiment includes an outlet rotating flange 8 provided on an outlet rotating cylinder 26 for waste a (on the outlet side of the decomposition target) and a non-rotating outlet fixed cylinder 35a (outlet fixed side). 2), a low oxygen gas filling space 11 filled with low oxygen gas is provided outside the sliding surface 5b between the outlet fixing flange 9 and the outlet fixing flange 9.

The oxygen concentration of the low oxygen gas is 5% or less and 5%
Beyond gases if leaked inside the drum body (waste a side), a possibility to increase the internal concentration of oxygen to reduce the amount of heat generated increases and pyrolysis gas G _1. Practically, the oxygen concentration of the low oxygen gas is 3 to 5%, and it is more preferable that the oxygen concentration be lower than 3%. As a type of the low oxygen gas, an inert gas such as a nitrogen gas or a carbon dioxide gas is used. Combustion gas produced by burning some fuel can be used if the oxygen concentration is 5% or less.

The low oxygen gas filling space 11 is formed by providing a jacket 12 between the outlet rotary flange 8 and the outlet fixed cylinder 35a.
Sealing is performed by an O-ring 15 fitted into the holding ring 14, and the other end 16 side of the jacket 12 is fixed to an outlet fixed cylinder 35.
a is hermetically fixed. Low oxygen gas filling space 11
Is always filled with a low oxygen gas, but it is preferable to provide a low oxygen gas replenishing pipe 18 so that the low oxygen gas can be replenished in case of consumption.

An annular groove 19 to which grease is supplied is formed in the sliding surface 5b. In preparation for grease consumption, an introduction hole 20 leading to the annular groove 19 and the grease supply pipe 2 are formed.
It is better to provide 1.

The seal portion 4 of the thermal decomposition reactor according to the present embodiment having the above-described structure operates as follows. That is, in the case where the low oxygen gas filling space 11 filled with the low oxygen gas is provided on the outside communicating with the sliding surface 5b, the external air does not leak directly into the drum main body 24 of the thermal decomposition reactor. Even if the low oxygen gas in the filling space 11 enters the drum main body 24, only the gas having a low oxygen concentration penetrates, and the inside of the drum main body 24 is maintained in a low oxygen atmosphere. Further, when the oxygen concentration of the low oxygen gas is 5% or less, the oxygen concentration is sufficiently low, so that the low oxygen atmosphere inside the drum main body 24 is reliably maintained.

FIG. 2 is a sectional view of a principal part showing a second embodiment similar to FIG. The sliding surface 5b of the seal portion according to the second embodiment extends outward to a position where the thermal effect due to the temperature of about 450 ° C. inside the thermal decomposition reactor is small, specifically, the sliding surface 5b.
b so that the temperature of b is about 200 ° C. or less.
6 or a distance 22 from the outside of the fixed outlet cylinder 35a. Further, a cooling water flow path 2 for cooling the sliding surface 5b
3 is provided. The cooling water flow path 23 is provided at an appropriate position continuously or at a predetermined interval in the circumferential direction of the outlet fixing flange 9, and usually forms a passage through which water passes in the outlet fixing flange 9, and is fixed at the outlet. The flange 9 is cooled with water.

The seal portion 4 of the second embodiment having the above-described structure has the same operation as the seal portion of the first embodiment, and the sliding surface 5b is affected by the heat effect inside the pyrolysis reactor 2. Since the sliding surface 5b is provided to be spaced apart to the outside to a small position, the temperature of the sliding surface 5b does not increase, and the outflow of grease and the deterioration of the temperature are prevented, and the sealing performance of the seal portion 4 is maintained. Furthermore, the sliding surface 5
b provided with a cooling water passage 23 for cooling the sliding surface 5
The temperature of b can be ensured to be equal to or lower than a temperature at which no grease flows out and excessive deterioration occurs.

FIG. 3 is a sectional view of a principal part showing a third embodiment similar to FIG. The seal part 4 according to the third embodiment includes:
The low oxygen gas filling space 11 is formed by forming an overhang portion 8a overhanging on the outlet fixing flange 9 outside the outlet rotation flange 8 and providing an annular groove 8b in the overhang portion 8a. In this embodiment, the overhang portion 8a is nothing but an example of the jacket of the present invention. In the low oxygen gas filling space 11, 2
It is preferable to provide a low oxygen gas replenishing pipe 18 indicated by a dashed line. Further, an O-ring groove 8c into which the O-ring 17 is fitted is provided inside the overhang portion 8a. The outlet fixing flange 9 has annular grooves 19a, 1
9b is formed. It is preferable to provide a grease supply pipe 21 for supplying grease in the annular grooves 19a and 19b.

The seal portion 4 according to the third embodiment has the same function as the seal portion according to the first embodiment, and can be formed compactly.

In the above embodiment, the seal portion 4 on the outlet side of the pyrolysis reactor 2 has been described. However, the seal portion 3 on the inlet side of the pyrolysis reactor 2, that is, the inlet which does not rotate with the inlet rotary cylinder 25. The same sealing structure and operation as above are also provided between the fixed cylinder 30a. However,
Since the temperature of the sliding surface on the inlet side of the decomposition product is usually 300 ° C. or less, it is not necessary to provide a cooling water flow path in many cases.

Further, the waste treatment apparatus 1 described above is provided with any one of the above-mentioned thermal decomposition reactors, and can improve treatment efficiency and maintenance.

[0032]

According to the pyrolysis reactor of the present invention, the inlet of the rotating body and the fixed side of the inlet that does not rotate and the rotating body and the fixed side of the outlet of the rotating body and the non-rotating outlet are fixed. The sealability of the sliding surface between the two is good, and the inside of the body is maintained in a low oxygen atmosphere.

Further, according to the waste treatment apparatus of the present invention, by providing the above-mentioned thermal decomposition reactor, the treatment efficiency and maintenance thereof can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a first embodiment of a pyrolysis reactor according to the present invention.

FIG. 2 is a sectional view of a main part showing a second embodiment similar to FIG.

FIG. 3 is a sectional view of a main part showing a third embodiment similar to FIG. 1;

FIG. 4 is a system diagram showing one embodiment of a waste disposal apparatus according to the present invention.

FIG. 5 is a schematic vertical sectional view of a thermal decomposition reactor provided in the waste treatment apparatus of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Waste treatment apparatus 2 Pyrolysis reactor 3, 4 Seal part of pyrolysis reactor 5a, 5b Sliding surface 11 Low oxygen gas filling space 23 Cooling water channel 24 Drum main body (body) 25 Inlet rotary cylinder (pyrolysis Object inlet side) 26 Outlet rotary cylinder (to-be-decomposed material outlet side) 30a Inlet fixed cylinder (inlet fixed side) 35a Outlet fixed cylinder (outlet fixed side) 38 Separation device 41 Combustion melting furnace (combustion furnace) G ₁ Pyrolysis gas a Waste (thermal decomposition product) b Thermal decomposition residue c Flammable component d Non-flammable component h Heated air (heat medium)

Claims (5)

[Claims] 1. A pyrolysis product supplied to a rotating body is thermally decomposed by a heat medium to generate a pyrolysis gas and a pyrolysis residue mainly composed of a nonvolatile component. In the pyrolysis reactor that discharges the residue, a sliding surface between the inlet of the body to be decomposed and the fixed side of the inlet that does not rotate, and the fixed side of the body that does not rotate and the outlet of the body that does not rotate A sliding surface between at least one of the sliding surfaces between the sliding surface and the jacket, and a low oxygen gas filling space filled with a low oxygen gas is provided between the sliding surface and the jacket. Characterized pyrolysis reactor. 2. The thermal decomposition reactor according to claim 1, wherein the sliding surface is provided at a position outside the thermal decomposition reactor to a position where heat influence is small. 3. The thermal decomposition reactor according to claim 1, further comprising a cooling water passage for cooling the sliding surface. 4. The thermal decomposition reactor according to claim 1, wherein the oxygen concentration of the low oxygen gas is 5% or less. 5. A pyrolysis reactor that pyrolyzes waste with a heat medium to generate a pyrolysis gas and a pyrolysis residue mainly composed of a nonvolatile component, and the pyrolysis discharged from the pyrolysis reactor. In a waste treatment apparatus having a separation device for separating a residue into a combustible component and a non-combustible component, and a combustion furnace for transferring and burning the pyrolysis gas and the combustible component, the pyrolysis reactor includes: A waste treatment apparatus comprising the pyrolysis reactor according to claim 1.