JP2005179405A - Apparatus for feeding granular raw material for biomass conversion type gas producer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for feeding a vegetable granular raw material for a biomass conversion type gas producer designed to prevent clogging of a charging pipe with the vegetable granular raw material such as wood flour, stably feed the vegetable granules into the furnace and thereby excellently safely and stably perform operation. <P>SOLUTION: The apparatus is composed as follows. The vegetable granular raw material is transported through a screw conveyor 12 arranged in the intermediate part of a granular raw material tank 11 and the charging pipe 13 into the interior of a biomass gas furnace while continuously applying a pressure to the vegetable granular raw material without causing clogging as indicated by a drawing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a biomass conversion-type gas generator that generates flammable useful gas such as carbon monoxide and hydrogen using plant fuel such as vegetation as a raw material, and particularly into a plant fuel furnace in the form of fine powder. The present invention relates to a biomass conversion gas generator having a novel structure that can be stably charged and has improved safety.

  Conventionally, it is one of the energy utilization technologies by gasification of biomass as a kind of utilization equipment of wood waste such as chips, sawdust and shavings, wood chips, thinned wood, etc. generated in large quantities in the wood processing industry etc. A biomass conversion type gas generator is known.

  For example, as disclosed in Patent Document 1, such a gas generator is provided with an air inlet at the lower part of a vertical hollow furnace body and an input pipe that extends through the upper wall in a substantially vertical direction. Then, while supplying wood powder etc. into the furnace through the input pipe from the fuel tank installed above the furnace body, the pyrolyzed wood powder etc. is oxidized and burned at the bottom of the wood powder etc. accumulated in the furnace The wood powder or the like is dried and thermally decomposed by the generated heat to generate pyrolysis gas. In addition, the pyrolysis gas generated in the middle to lower layer of wood powder accumulated in the furnace is cooled and filtered by passing through the accumulated wood powder and the like, and then opened to the top of the furnace body It is designed to be taken out of the furnace by being sucked through the suction tube, and then removed as dust or tar by an appropriate purification device such as a cyclone, so that it can be used as a clean and combustible useful gas. Will be served.

Japanese Utility Model Publication No. 6-84109

  According to a known technique, a fuel tank is placed and fixed on the upper wall of the furnace body. This fuel tank is a hollow circular or hollow cylindrical container. A hopper is disposed above the fuel tank, and a discharge port formed at the lower end of the hopper opens above the fuel receiving port of the fuel tank. I'm hurt.

  And the wood powder etc. used as a fuel are supplied to a fuel tank through a conveyance pipe by a pneumatic conveyor or the like. Further, wood powder or the like supplied to the fuel tank can be introduced into the fuel tank as necessary.

  However, in conventional gas generators, raw materials such as wood powder fall in the middle of the input pipe depending on various conditions such as the shape of fine powder and wood powder supplied from the fuel tank, moisture content, and tightening conditions. There was often a situation where shelves could not be smoothly supplied due to the shelving phenomenon. For this reason, stable operation cannot be performed and there are safety problems such as abnormal combustion.

  On the other hand, as shown in Patent Document 2, the present inventors arranged a feed pipe tapered so as to expand downward, a feed screw from the upper end of the feed pipe downward, and wood powder. I devised a device that forcibly feeds etc. This improved clogging, but it was not enough.

Japanese Patent Application No. 2002-287031

  The problem to be solved by the present invention is that clogging of plant powder material such as wood powder into the input pipe is prevented, and the plant powder can be stably supplied into the furnace. Therefore, an object of the present invention is to provide a plant powder raw material supply device for a biomass conversion gas generator that can be stably operated with excellent safety.

  The present invention has been made in order to solve the above-described problems, and the plant granular material is obtained via a screw conveyor (Screw conveyor) disposed between the granular material raw material tank and the input pipe. This is accomplished by configuring the apparatus to be transported into the biomass gas furnace without causing clogging.

  Specifically, the apparatus of the present invention is configured to supply plant powder raw materials such as wood powder from a powder raw material tank installed above a vertical hollow furnace body having a cylindrical peripheral wall. While supplying to the inside of the furnace body through an input pipe arranged through the upper part of the body, the plant granular material is pyrolyzed inside the furnace body and the generated gas is sucked and collected outside the furnace body. In the biomass conversion type gas generator configured as described above, a screw conveyor (Screw conveyor) is arranged in the middle part of the granular material raw material tank and the input pipe, and the raw material discharge port of the granular material raw material tank and the screw conveyor (Screw conveyor) are arranged. ), And the raw material outlet of the screw conveyor (Screw conveyor) and the upper opening of the input pipe are connected to each other by a connecting pipe. That.

  As a result, the vegetable powder raw material (hereinafter abbreviated as powder raw material) is continuously pumped from the screw conveyor to the charging pipe and is always pushed downward into the powder raw material in the charging pipe. By applying the pressure, clogging is prevented, and the road cover also functions as a material seal (sealed state with raw materials).

  According to the present invention, it is possible to stably supply powder raw materials to a biomass conversion gas generating furnace, and it is possible to stably operate with excellent safety, and it is excellent in labor saving, safety and economy. We were able to supply the equipment.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 schematically shows the entire structure of a gas generator including a plant powder raw material supply apparatus as one embodiment of the present invention. FIG. 2 shows an enlarged schematic diagram of the plant powder supply apparatus, and FIG. 3 shows a schematic diagram of the screw conveyor.

  That is, in FIG. 1, the furnace body peripheral wall 10 has a thick large-diameter cylindrical shape, and a pyrolysis chamber is formed therein. In this thermal decomposition chamber, powdery raw materials such as wood powder supplied from above are deposited and subjected to treatments such as oxidation and decomposition. Although omitted in the drawings, the peripheral wall is formed with a multilayer fireproof structure in which sand is filled between an inner peripheral wall formed of refractory bricks and an outer peripheral wall formed of reinforced concrete, for example. Further, the inner peripheral surface of the peripheral wall 10 may have a cylindrical shape with a taper that decreases in diameter toward the upper side in addition to a cylindrical shape that extends substantially vertically. Further, the size of the furnace body is not particularly limited, but in the practical size, the outer diameter and the height of the peripheral wall 10 both reach several meters or more.

  In addition, a rooster (grate) is installed in the lower part of the furnace body, and an appropriate amount of air is supplied into the pyrolysis chamber by an air supply device disposed below the rooster. . An appropriate number of air supply pipes can be installed. Further, a scraping device that discharges ash after pyrolysis, undecomposed wood flour, and the like to the outside of the furnace is disposed at the lower part of the rooster.

  In addition, a gas extraction pipe for taking out the generated gas generated in the pyrolysis chamber is disposed on the upper wall of the furnace body, and a gas flow meter and a gas analyzer are provided in the gas extraction pipe. Generally attached. Further, a thermocouple for measuring the temperature in the furnace, a pressure sensor for measuring pressure, and an inert gas injection pipe for extinguishing the fire in abnormal combustion may be installed in the furnace.

  Now, in the upper part of the furnace body, a charging pipe 13 is disposed through the central portion thereof. The charging pipe 13 has a cylindrical or rectangular tube shape, and is substantially fixedly supported by the furnace body with its central axis extending in the vertical direction. By the way, the input pipe 13 may have a taper that gradually expands downward. The upper end portion of the charging pipe 13 is projected upward from the upper wall of the furnace body at a predetermined height, while the lower end portion thereof is inserted into the pyrolysis chamber of the furnace body.

  The upper part of the input pipe 13 is connected to the raw material discharge port of the screw conveyor 12, and the powder material such as wood flour is supplied to the input pipe 13 from the screw conveyor 12 while being pressed through the connection pipe 22. Is done. The granular material such as wood powder is smoothly supplied into the furnace by this pressing action without causing inconvenience such as a shelving phenomenon in the input pipe. Here, the supply amount of the granular material can be controlled by the rotational speed of the screw conveyor 12.

  Next, on the screw conveyor 12, a powder material tank 11 is placed and fixed. As shown in the plan view of FIG. 4, the granular material raw material tank 11 is a hollow cylindrical container having a circular bottom wall and a cylindrical tube wall, and extends along the upper surface of the bottom wall. A propeller-like rotator provided with a plurality of stirring blades is disposed so as to spread, and is supported by a rotation support shaft disposed on the central axis of the fuel tank. The rotating support shaft is rotated by an electric motor, so that the rotating body rotates around the central axis. And the action | operation which the wood flour etc. in a fuel tank presses toward an outer peripheral side and is sent with the stirring blade which rotates is added.

  Furthermore, a raw material discharge port is provided in the bottom wall of the powder material raw material tank 11 near an intermediate portion between the outer peripheral edge portion and the central axis. The inlets are connected by a connecting pipe 21. Thereby, the wood powder etc. in the granular material raw material tank 11 are introduced into the screw conveyor 12. Here, the shape of the raw material discharge port of the granular material raw material tank, the connecting pipe, and the raw material reception port of the screw conveyor may be any of a rectangular shape, an elliptical shape, a circular shape, and the like. Correspondingly, the connecting pipe shape may be rectangular, elliptical, circular, or the like.

  As a result, the consumption reduction amount of wood powder and the like in the furnace is stably supplied, and the inside of the charging pipe is always filled with wood powder and the like due to the so-called material seal effect, The gas generated in the furnace is prevented from flowing upward. In addition, the dimensions and equipment capacity of the input pipe, screw conveyor, and powder material tank are determined based on the internal dimensions of the furnace, the height of the accumulated wood powder, etc. Is appropriately set so that the target amount of effective gas can be collected as stably as possible.

  In addition, a granular material raw material is introduce | transduced into the granular material raw material tank 11 by a usual method. For example, a granular material such as wood powder is supplied from an external storage tank (not shown) to a hopper by a pneumatic conveyor using a conveyance fan, and further, from the hopper, if necessary, a granular material. It is introduced into the tank 11.

The wood powder with an average particle diameter of 1 mm is supplied to a powder raw material tank having a diameter of 2 m and a height of 1.4 m having a rectangular raw material discharge port having a width of 40 cm and a length of 1.5 m on its lower wall. With a rotating propeller equipped with four stirring blades so as to spread along the upper surface of the wall, 3 m ³ of wood flour per hour was discharged from the discharge port to the screw conveyor through the connecting pipe. As the rotating propeller at this time, a motor with a power of 2.2 kw and a 1/20 speed reducer was used.

The wood powder sent from the above-mentioned granular material raw material tank is supplied to a screw conveyor having an equivalent raw material inlet dimension through a connecting pipe having a square tube shape with a cross-sectional shape of width 40 cm and length 1.5 m, From the raw material discharge port (a square shape having a width of 40 cm and a length of 40 cm) of the screw conveyor, it was pressure-fed into the charging pipe through a connecting pipe having an equivalent cross-sectional shape. The screw conveyor having an outer diameter of 38 cm, a length of 2 m, a screw blade pitch of 25 cm, a power of 2.2 kw, and 400 rpm was used. In addition, the screw conveyor was placed on the upper part of the biomass gas furnace with a 15-degree inclination with the raw material receiving port at the top.

  Next, the wood powder fed from the screw conveyor was supplied to the charging pipe through a square tube having a width of 40 cm, a length of 40 cm, and a height of 10 cm. The input pipe used at this time was an upper opening (width 40 cm, length 40 cm), a lower opening (width 50 cm, length 50 cm), a height of 1 m, and a taper-shaped pipe that expanded downward. Note that all of the above powder material tank, screw conveyor, charging pipe and connecting pipes were made of steel.

  With the raw material supply device having the above-described configuration, the raw material could be supplied smoothly without causing clogging of the granular material in the charging pipe.

It is the schematic which shows the apparatus structure of the biomass conversion type gas generating furnace containing a granular material raw material supply apparatus. It is the schematic which shows the structure of a granular material raw material supply apparatus. It is the schematic which shows a screw conveyor. It is a plane schematic diagram showing a granular material raw material tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Furnace peripheral wall 11 Granule raw material tank 12 Screw conveyor 13 Input pipe 21 Connection pipe of powder raw material tank and screw conveyor 22 Connection pipe of screw conveyor and input pipe

Claims (1)

From the powder material tank installed above the vertical hollow furnace body with a cylindrical peripheral wall, plant powder material such as wood flour is placed through the top of the furnace body. In the biomass conversion type gas generator that is supplied to the inside of the furnace body through the pipe, and the plant powder raw material is pyrolyzed inside the furnace body and the generated gas is sucked and collected outside the furnace, A screw conveyor (Screw conveyor) is arranged in the middle of the powder material tank and the input pipe, a material outlet of the powder material tank, a material inlet of the screw conveyor, and the screw conveyor (Screw conveyor) A raw material supply device for a biomass conversion gas generator for a biomass conversion gas generator, in which the raw material outlet and the upper opening of the input pipe are each connected by a connecting pipe.

Images