JP2013185093A - Pyrolytic gasifying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pyrolytic gasifying apparatus capable of producing a thermally decomposed gas having an uniform composition ratio by uniformalizing a heating temperature distribution.SOLUTION: In a pyrolytic gasifying apparatus for producing thermally decomposed gas by heating a carbonized material obtained by carbonizing organic waste in a carbonization furnace and a gasifying agent in a pyrolytic gasifying furnace 2, the pyrolytic gasifying furnace 2 is provided with: a cylindrical outer cylinder 4 which is provided with opening parts in the upper and lower end part and in which the opening part of the lower end part is connected to the carbonization furnace; an inner cylinder 12 which is provided with an opening part opened in the lower end part and provided with a thermally decomposed gas discharge path 17 in the upper end to be connected to a carbonized material supply means 18 for supplying the carbonized material and an opening part connected to a gasifying agent supplying means for supplying the gasifying agent and which is formed in a cylinder form to be provided inside the outer cylinder; a turntable 13 freely rotatably arranged with a gap from the inner cylinder lower end part in the under side of the inner cylinder 12; and a heat storing projection 14 provided in the rotary center part of the turntable 13 and arranged inside the inner cylinder with a gap at an interval equal substantially from the circumferential wall of the inner cylinder 12.

Description

  The present invention relates to a pyrolysis gasification apparatus that produces pyrolysis gas by chemically changing biomass (organic waste such as waste wood) by pyrolysis and gasification.

In recent years, pyrolysis gasification of woody materials containing a large amount of biomass, particularly lignin, has great potential as a source of new energy resources, and attempts have been made to effectively use it. In order to pyrolyze and convert wood-based materials, the raw material wood biomass is gas (CO, H ₂ , CH ₄ , CO ₂ , H ₂ O), carbide, carbonization in a low oxygen state at a temperature of 200 to 600 ° C. It decomposes into hydrogen, the pyrolysis product is supplied with oxygen or air under restriction and burned, and then the carbide is heated to a high temperature and gasified to produce a water gas.

  In addition to the fact that the consumption of fossil fuels caused global warming in the 1990s, the Great East Japan Earthquake on March 11, 2011, as an alternative energy resource to replace fossil fuels from biomass and waste In addition to steam turbine power generation using a boiler facility, a method of recovering energy by a conventional technique has been attracting attention, and power generation efficiency exceeding 20% is obtained by generating power with a gas engine having high power generation efficiency using generated gas as fuel gas. In addition, since the synthesis gas obtained by gasification also becomes a raw material for liquid fuels such as metal rule, synthetic light oil, and mixed alcohol, gasification technology is attracting attention as one of petroleum alternative combustion technologies.

  An apparatus for pyrolyzing carbide from biomass such as waste wood to generate pyrolysis gas is, for example, an externally heated cracking gasification furnace described in Patent Document 1. The externally heated cracking gasification furnace described in Patent Document 1 has a double structure in which an outer cylinder part that allows the exhaust gas of the steam heater to pass through is disposed outside the gasification furnace main body that is an inner cylinder arranged in the horizontal direction. A screw conveyor is installed in the axial direction inside the inner cylinder.

JP 2004-35837 A

  However, in the conventional fixed-bed furnace or the like, even if the gasification furnace main body is heated from the outside to a high temperature of 800 ° C. or higher, in the gasification furnace having a large inner cylinder volume, the carbide introduced into the inside is uniformly and quickly. It is difficult to heat to a high temperature, and unstable elements such as unevenness in the heating temperature distribution are high, and the composition ratio of the generated pyrolysis gas may be blurred. Therefore, there is a demand for a pyrolysis gasification technique in which the carbide inside the inner cylinder is uniformly and quickly heated to a high temperature to obtain a pyrolysis gas having a uniform composition ratio.

  The present invention has been made in order to solve the above-mentioned problems, and there are no unstable elements in the furnace such as the furnace clogging, ratholes in the hopper, uneven heating temperature distribution of carbides, and water gasification. In addition, the conversion efficiency (cold gas efficiency) is high, and a clean water gas containing no impurities can be obtained. And it aims at providing the thermal decomposition gasification apparatus which can produce | generate the thermal decomposition gas with a uniform composition ratio by heating at high temperature so that heating temperature distribution may become uniform.

In order to solve the above-mentioned problems, the present invention heats a carbonized product obtained by carbonizing organic waste in a carbonization furnace and a gasifying agent by a high-temperature combustion gas generated in the carbonization furnace in a pyrolysis gasification furnace. A pyrolysis gasifier that generates pyrolysis gas,
The pyrolysis gasification furnace has a cylindrical outer cylinder having an opening at the upper and lower ends and an opening at the lower end connected to the carbonization furnace, and a pyrolysis gas discharge path at the upper end and opened at the upper end. An opening connected to the carbide supplying means for supplying carbide to the middle or near the lower end and an opening connected to the gasifying agent supplying means for supplying the gasifying agent are formed in a cylindrical shape inside the outer cylinder. An inner cylinder provided, a turntable disposed below the inner cylinder with a gap from a lower end of the inner cylinder, and a rotatable table; and a circumferential wall of the inner cylinder provided at a rotation center of the turntable. A heat storage protrusion disposed inside the inner cylinder with gaps at equal intervals, and
A gap between the inner cylinder and the heat storage protrusion is configured as a gasification region of carbide. Combustion gas generated in a carbonization furnace is introduced into the gap between the outer cylinder and the inner cylinder. A thermal decomposition gasification apparatus is configured such that the temperature distribution is further stabilized by heating the heat storage protrusion and heating the carbide in the gasification region by the radiant heat.

  Moreover, in order to solve the said subject, this invention sets it as the said thermal decomposition gasification apparatus characterized by the said thermal storage protrusion consisting of any one of casting, another metal, or ceramic. Is preferred.

  In order to solve the above-mentioned problem, the present invention sets the distance from the inner wall of the inner cylinder to the heat storage protrusion to be in the range of 20 to 100 mm and the heat storage protrusion to be in the range of 200 to 1000 mm. It is preferable to use the above-described pyrolysis gasifier.

  In order to solve the above-mentioned problem, the present invention is characterized in that the opening connected to the carbide supply means for supplying carbide in the inner cylinder is provided above the head of the heat storage protrusion. It is preferable to use the above-described pyrolysis gasifier.

  In order to solve the above problem, the present invention is characterized in that the gasifying agent supply means for supplying the gasifying agent in the inner cylinder sprays the gasifying agent toward the gasification region inside the inner cylinder. Preferably, the thermal decomposition gasification apparatus is characterized.

  The pyrolysis gasification furnace of the pyrolysis gasification apparatus according to the present invention includes a turntable that is rotatably disposed with a gap from the lower end of the inner cylinder below the inner cylinder, and the rotation of the turntable. The heat storage protrusion itself is heated by providing the heat storage protrusion provided in the center portion with a space inside the inner cylinder, and the carbide in the gasification region is on both sides of the inner cylinder and the heat storage protrusion. Is heated by radiant heat. Moreover, in the gasification region, the gap between the inner cylinder and the heat storage protrusion is relatively narrow and rotates together with the turntable so that heat conduction to the carbide is facilitated, and the carbide is efficiently and quickly made uniform in temperature distribution. By heating at a high temperature, it is possible to efficiently generate a pyrolysis gas having a uniform composition ratio.

(A) is a partial cross-sectional top view which shows the inner and outer cylinder part of a pyrolysis gasification furnace, (b) is the structure which shows the whole pyrolysis gasification furnace containing the AA line partial cross section side view of (a). FIG. It is a block diagram which shows the thermal decomposition gasification apparatus which concerns on this invention. It is a principal part block diagram which shows the thermal decomposition gasification apparatus which concerns on this invention.

  DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention (hereinafter referred to as “embodiments”) will be described in detail below with reference to the drawings. However, the present invention is not limited to such an embodiment.

  2 and 3 show a pyrolysis gasification apparatus 1 according to the present embodiment, and FIG. 1 shows a pyrolysis gasification furnace. As shown in FIG. 1, in the embodiment of the present invention, reference numeral 2 denotes a pyrolysis gasification furnace. Both the outer cylinder 11 and the inner cylinder 12 are cylindrical, and the outer cylinder 11 and the inner cylinder are concentric with each other. 12 is erected with a gap 23, the upper and lower ends of the outer cylinder 11 are brought into close contact with the inner cylinder 12, and the combustion gas generated in the carbonization furnace is introduced into the gap 23 from the combustion gas inlet 15 which is a lower opening. And it is comprised so that it may discharge | emit from the combustion gas discharge port 16 which is an upper opening part. The upper end portion of the inner cylinder is connected to the pyrolysis gas discharge passage 17, the lower end portion of the inner cylinder is opened, and the turntable 13 is disposed with a gap from the lower end portion of the inner cylinder. The turntable has a conical shape, and a columnar heat storage protrusion 14 is erected on the top of the turntable, and the heat storage protrusion is disposed inside the inner cylinder so that there are gaps at substantially equal intervals from the inner cylinder peripheral wall. ing. The turntable is configured to rotate at a predetermined speed by a motor M supported by a rotating shaft extending downward from a central portion.

  Carbide supplying means 18 for supplying carbide is connected to an opening 19 of the inner cylinder through the outer cylinder near the middle part to the lower end of the inner cylinder 12. Although it does not specifically limit as the carbide | carbonized_material supply means 18, For example, a screw conveyor etc. are preferable. An opening 21 for ejecting water vapor as a gasifying agent is formed in the inner cylinder peripheral wall provided with the heat storage protrusion 14, and the gas generating agent supply means 20 is configured to eject water vapor. .

  The material of the heat storage protrusion 14 is not particularly limited as long as it has heat storage properties and heat resistance capable of withstanding the gasification temperature, but is preferably a casting, other metal or ceramic, and particularly preferably a casting. . The temperature inside the inner cylinder is adjusted in advance so that the temperature inside the inner cylinder is 800 to 900 ° C., preferably around 750 to 800 ° C., depending on the temperature of the combustion gas (900 to 1000 ° C.) passing through the gap between the inner cylinder and the outer cylinder. It is preferable that the material of the heat storage protrusion has a heat resistance of at least 1000 ° C. or more. Casting is made of cast iron with a carbon content of 2% or more and cast by casting cast iron melted into a sand mold or mold. As cast iron, flake graphite cast iron (FC) called hard gray cast iron, tensile strength Any of large spheroidal graphite cast iron (FCD), CV cast iron in the middle of flake graphite cast iron and spheroidal graphite cast iron may be used, but gray cast iron having a relatively high specific heat and a high melting point is preferable.

  Table 1 shows the thermal properties of gray cast iron and other metals and ceramics. In addition to castings, metals and ceramics having heat resistance shown in Table 1 can be used. Aluminum has a large specific heat but a low melting point, so it is difficult to use alone, but it may be used as an alloy. A gap 22 between the inner cylinder 12 and the heat storage protrusion 14 is configured as a gasification region of carbide. Combustion gas generated in a carbonization furnace is introduced into the gap 23 between the outer cylinder and the inner cylinder, and the combustion gas causes the inner gas to pass through the inner cylinder 12. The inside of the cylinder and the heat storage projection are heated, and the carbide in the gasification region is heated by the radiant heat, whereby the temperature distribution is further stabilized. Further, it is preferable that a shaft is provided in the center of the turntable in advance so that heat storage protrusions of different sizes and materials can be exchangeably mounted on the shaft. Although the shape of the heat storage protrusion is not particularly limited, for example, a cylindrical shape or a columnar shape with a sealed head is preferable.

  As described above, the gap 22 between the inner cylinder 12 and the heat storage protrusion 14 is used as a carbide gasification region, and water vapor as a gasifying agent is sprayed on the carbide in the gasification region, and the inner cylinder 12 and the heat storage protrusion 14 are sprayed. It is heated and gasified by the radiant heat emitted from it. At that time, in order to quickly heat the carbide, it is preferable to make the gasification region as narrow as possible. However, since production efficiency is reduced if it is too narrow, the distance between the inner cylinder peripheral wall and the heat storage protrusion is 20 to 100 mm, and the height of the heat storage protrusion is 200 to 1000 mm. It is preferable to adjust appropriately considering the heating time and the speed of passing through the gasification region, that is, the gap between the turntable 13 and the inner cylinder, the size of carbides, and the like.

  Next, with reference to FIG. 2 and 3, the structural example of the thermal decomposition gasification apparatus of this-application embodiment is demonstrated. As shown in FIGS. 2 and 3, the pyrolysis gasification apparatus of the present embodiment includes a carbonization furnace 3 and a pyrolysis gasification furnace 2.

First, the carbonization furnace 3 decomposes biomass organic waste into gas (CO, H ₂ , CH ₄ , CO ₂ , H ₂ O), carbides, hydrocarbons in a low oxygen state at a temperature of 200 to 600 ° C., The hydrocarbon gas is separated into a hydrocarbon and a hydrocarbon gas, and the hydrocarbon gas is subjected to secondary combustion in the combustion chamber to generate a combustion gas at 900 to 1000 ° C., and the combustion gas passes through the opening 15 at the lower end of the pyrolysis gasification furnace 3. Supplied to the area.

  The carbide supply means 18 supplies the carbide supplied from the carbonization furnace 3 into the inner cylinder 12 of the pyrolysis gasification furnace 2. When the carbide supplied to the inside of the inner cylinder 12 falls and reaches the gasification region 22, it is contact-mixed with water vapor ejected from a plurality of gasifying agent supply ports 21 provided on the inner cylinder peripheral surface. The injection amount of water vapor can be adjusted by a gasifying agent supply means (not shown), and the component composition ratio of the pyrolysis gas can be adjusted by controlling the reaction. The carbide mixed in contact with water vapor in the gasification region 22 receives radiant heat from both surfaces of the inner cylinder wall and the heat storage protrusion, and the heat storage protrusion 14 rotates while the turntable 13 rotates (for example, 5 to 10 rpm). Move downward gradually. The residue of the gasified carbide passes through the turntable 13 and the gap 24 between the inner cylinders and is discharged to the outside from the discharge port 25.

In the gasification region 22, a water gasification reaction (C + H ₂ O → CO + H ₂ −28.36 kcal / mol) which is an endothermic reaction and a water gas shift reaction (CO + H ₂ O → CO ₂ + H ₂ +9.85 kcal / mol) which is an exothermic reaction. ) Proceeds continuously. As a result, a pyrolysis gas composed of hydrogen (H ₂ ), carbon monoxide (CO), and carbon dioxide (CO ₂ ) components is generated. In general, the water gas shift reaction, which is an exothermic reaction, is promoted at low temperatures (750 to 800 ° C.), and high calorie carbon monoxide is consumed and low calorie hydrogen is generated, so the calorific value per unit volume is small. A hydrogen-rich pyrolysis gas is produced, and a carbon monoxide-rich pyrolysis gas is produced at a high temperature (900 to 950 ° C.). Further, as the amount of water vapor supplied from the gasifying agent increases, the H ₂ / CO ratio in the pyrolysis gas increases.

  Next, examples will be described. An experimental pyrolysis gasification furnace shown in FIG. 1 was prepared. The outer cylinder was formed of a refractory material having an outer diameter of φ460 mm, a height of 1380 mm, and a thickness of 50 mm, and the inner cylinder was formed of a heat-resistant nickel chrome steel plate having an outer diameter of φ150 mm and a thickness of 8 mm. Furthermore, the heat storage protrusion was formed of a casting having an outer diameter of φ84 mm and a height of 230 mm, and the width of the gasification region, which is a gap from the heat storage protrusion to the inner cylinder, was adjusted to 25 mm on one side. A conventional self-burning type carbonizing furnace was used as the carbonizing furnace. As the raw material carbide, bulk coal having a size passing through a width of 25 mm in the gasification region was used.

Carbonize organic waste such as waste wood with a moisture content of 20% using a self-combustion type carbonization furnace, and adjust the temperature of the gasification region to 750-800 ° C in the above-mentioned pyrolysis gasification furnace for experiments. As a result of continuous operation, the composition ratio of the obtained gasification component is 60% for hydrogen (H ₂ ), 20% for carbon monoxide (CO), and 20% for carbon dioxide (CO ₂ ). It was confirmed that the component ratio was not blurred at all.

  The pyrolysis gasification apparatus according to the present invention is fast in water gasification and has high conversion efficiency (cold gas efficiency) and a clean water gas containing no impurities. In addition, by providing high-temperature heating so that the heating temperature distribution is uniform, a pyrolysis gasifier capable of generating a pyrolysis gas with a uniform composition ratio is provided, and at the same time, it is extremely energy saving, environmental protection, and economical. Useful.

DESCRIPTION OF SYMBOLS 1 Pyrolysis gasifier 2 Pyrolysis gasification furnace 3 Carbonization furnace 11 Outer cylinder 12 Inner cylinder 13 Turntable 14 Thermal storage protrusion 15 Combustion gas introduction port 16 Combustion gas discharge port 17 Pyrolysis gas discharge channel 18 Carbide supply means 19 Carbide Supply port 20 Gasifying agent supply path 21 Gasifying agent supply port 22 Gap between the inner cylinder and the heat storage protrusion (gasification region)
23 Gap between outer cylinder and inner cylinder (combustion gas region)
24 Gap 25 Discharge M Motor

Claims (5)

A pyrolysis gasifier for generating pyrolysis gas by heating a carbonized material obtained by carbonizing organic waste in a carbonization furnace and a gasifying agent in the pyrolysis gasification furnace with a high-temperature combustion gas generated in the carbonization furnace. Because
The pyrolysis gasification furnace has a cylindrical outer cylinder having an opening at the upper and lower ends and an opening at the lower end connected to the carbonization furnace, and a pyrolysis gas discharge path at the upper end and opened at the upper end. An opening connected to the carbide supplying means for supplying carbide to the middle or near the lower end and an opening connected to the gasifying agent supplying means for supplying the gasifying agent are formed in a cylindrical shape inside the outer cylinder. An inner cylinder provided, a turntable disposed below the inner cylinder with a gap from a lower end of the inner cylinder, and a rotatable table; and a circumferential wall of the inner cylinder provided at a rotation center of the turntable. A heat storage protrusion disposed inside the inner cylinder with gaps at equal intervals, and
A gap between the inner cylinder and the heat storage protrusion is configured as a gasification region of carbide. Combustion gas generated in a carbonization furnace is introduced into the gap between the outer cylinder and the inner cylinder. A thermal decomposition gasification apparatus characterized in that the temperature distribution is further stabilized by heating the heat storage protrusion and heating the carbide in the gasification region by the radiant heat.   2. The pyrolysis gasifier according to claim 1, wherein the heat storage protrusion is made of any one of castings, other metals, and ceramics.   2. The pyrolysis gasifier according to claim 1, wherein a distance from an inner wall of the inner cylinder to the heat storage protrusion is set in a range of 20 to 100 mm, and a height of the heat storage protrusion is set in a range of 200 to 1000 mm. .   The pyrolysis gasifier according to claim 1, wherein an opening connected to a carbide supply means for supplying carbide in the inner cylinder is provided above a head of the heat storage protrusion.   The pyrolysis gasifier according to claim 1, wherein the gasifying agent supplying means for supplying the gasifying agent in the inner cylinder sprays the gasifying agent toward the gasification region inside the inner cylinder.

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