JPS60145904A - Carbonization and activation furnace - Google Patents

Abstract

PURPOSE:To produce an activated carbon fiber product (cloth, sheet, etc.) having uniform qualities, in high efficiency, by supplying activation gas to furnace from its bottom, and passing a material to be carbonized and activated continuously through the furnace via the gates opening at the top and the bottom of the furnace. CONSTITUTION:Activation gas generated by the generator 37 is supplied through the line 38 and the gate 36 to the furnace 39 composed of a furnace body 32 furnished with the top gate 30 and the bottom gate 31 each having gas curtain 41 and 42 (33 is a heater), and is discharged via an exhaust gas treating apparatus 45. The raw cloth 60 is introduced into the above modification furnace via the inlet of the upper closed chamber 43, passed via the gate 30 through the furnace 39 to activate the carbonized product, introduced via the gate 31 into the lower closed chamber 35, and wound with the automatic winder 64. In the above apparatus, the raw cloth can be activated in an optimum state by controlling the inert gas introducing port 40, the gas curtains 41, 42, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a carbonization/activation furnace for producing carbon fibers, particularly activated carbon fibers.

Structures of conventional examples and their problems In general, in order to obtain activated carbon powder by carbonizing and activating powders of palm and sawdust, and to obtain carbon fibers and activated carbon fibers by carbonizing and activating fibrous materials. ←1. A method is used in which the raw material is maintained at a temperature of BDO°C to 1600°C in an inert gas. In particular, in order to carry out an activated carbonization reaction, water vapor or other oxidizing gas is added to the non-carbonaceous gas at a constant concentration as an activating gas.

Conventionally, the equipment for carbonizing and activating such substances is
A high temperature furnace as shown in FIG. 1 has been used. That is, a porcelain reaction tube 2 is placed in an electric furnace 1 using a resistance heater made of nichrome, kanthal, silicon carbide, etc., and a sample 3 to be carbonized is placed in the reaction tube 2. The furnace 1 is maintained at a constant temperature by a temperature control device 4. The inert gas from the carrier gas cylinder 5 is fed into the reaction tube 2 through the entire steam generator 6. The exhaust gas is treated in a suitable exhaust gas treatment device 7. In particular, there are examples in which the reaction tube 2 is rotated using the motor 8.

In this way, an activation reactor basically causes a contact reaction between carbide and an activation gas at high temperatures. It is difficult to control the reaction atmosphere for carbonization activation. Among the carbonization and activation reactions mentioned above, the carbonization reaction requires a uniform carbonization reaction at high temperature in a low oxygen concentration atmosphere.

Taking water vapor activation as an example, the activation reaction is a solid phase-vapor phase reaction between water molecules and the carbon that constitutes the substrate under high temperature, and pores are created in the holes of the carbon atoms, as shown in equation 1. This results in a high specific surface area of activated carbon.

Cn+H20-+ Cn, +CO+H2- (1) In such a solid phase-gas phase reaction, (1) uniformity of the temperature of the system;
(2) high frequency and uniformity of contact between the solid surface and the gas; (3) rapid movement of substances produced by the activation reaction (Co and H2 gas in the case of the reaction of formula 1) to the outside of the system; The following three points are mentioned as the factors that govern the reaction. When the outsideness of and is well controlled, the activation reaction proceeds normally, and as a result, excellent activated carbon with a high specific surface area is obtained. If you change your perspective, these 3
It is possible to control the properties of the obtained activated carbon by arbitrarily controlling the conditions.
.

Since the amount of the substance to be activated is constant at one position, it is relatively easy to control the above activation conditions. In other words, the concentration and flow rate of the activation gas 9. The introduction path into the reaction tube.

Activated carbon with desired characteristics can be obtained by setting various parameters. However, since this method is a batch method, the amount of material to be activated per process is limited, and if this amount is large, it becomes difficult to uniformly carbonize and obtain the activated material. For example, in a batch furnace, the outer surface is activated more quickly than the inside, which makes the furnace structure complicated, such as rotation and stirring of the object to be activated.

FIG. 2 is a conceptual diagram of a conventional batch furnace for carbonizing cloth 20 obtained by weaving fibers. Otherwise, the activation gas 22 will not be able to come into uniform contact with the cloth 2o. 23 is an activation gas supply device, and 24 is a jig for suspending the cloth in the furnace.

As mentioned above, in conventional batch-type carbonization activation furnaces, it is difficult to carbonize large quantities of continuous long items such as cloth at once, and a furnace that can uniformly and continuously carbonize these items is desirable. It will be done.

Object of the Invention The present invention relates to a carbonization activation furnace capable of continuously obtaining carbon fibers and activated carbon fibers having uniform properties, and is capable of producing carbon fibers and activated carbon fibers in the form of cloth, sheet, etc. such as carbon fiber cloth and activated carbon fiber cloth. Felt-like carbon fiber.

A furnace for continuously obtaining activated carbon fiber composition is provided.

Composition of the Invention The carbonization activation furnace of the present invention has openings at the ceiling and bottom of the furnace chamber, and from the ceiling opening to the bottom opening, or from the bottom opening to the ceiling. The activation material to be carbonized is continuously moved and passed through the furnace chamber, and the activation gas is supplied from the introduction section at the bottom of the furnace chamber.

Here, it is preferable that the bottom opening is connected to a closed chamber capable of storing the carbonized activated product or the carbonized activated raw material.

The above-mentioned activation gas is supplied from a gas supply device consisting of a liquid vaporizer that extracts the liquid, a suction body in contact with the liquid, a heat generating part on the upper part of the suction body, and an inert gas supply device. According to the present invention, the activation gas uniformly contacts and reacts under constant conditions with the object to be activated, such as cloth, which moves continuously in the vertical direction within the furnace chamber. , the oxygen concentration and activation gas concentration in the furnace chamber are always kept constant by the closed chamber leading to the furnace chamber, and the activation gas supply device that can control the supply amount uniformly and with high precision is used, so it is not possible to use conventional batch carbonization. Compared to an activation furnace, it is possible to continuously obtain carbon fibers and activated carbon fiber compositions with uniform properties (specific surface area, basis weight, etc.) in large quantities.

DESCRIPTION OF EMBODIMENTS The basic structure of the carbonization activation furnace of the present invention is shown in FIG. That is, openings 30 and 3 are provided in the ceiling and the bottom, respectively.
1 is surrounded by a heating part 33 such as a silicon carbide heating element, and the whole is covered with a heat insulating part 34 made of a heat insulating material such as an alumina fiber composition or a brick. The opening 31 at the bottom of the furnace chamber is a sealed chamber 36.
It is connected to There is an activation gas supply hole 36 in the lower part of the furnace chamber, and the activation gas obtained by the activation gas generator 37 passes through a supply pipe 38 to reach the supply hole 36 and is supplied into the furnace chamber 39 . The inside of the furnace chamber 39 and the sealed chamber 35 are filled with an inert gas such as nitrogen used as a carrier gas for the activation gas, which will be described later, and an inert gas from an inert gas introduction hole 40 provided in the sealed chamber 35 to provide a gas concentration of 5% or less. maintained at a low oxygen concentration. Keeps heat in the furnace chamber 39 and oxygen concentration low and stable/
In addition, a gas curtain of inert gas may be provided at positions 41 and 42.

Furthermore, this carbonization activation furnace has several activation exhaust gas treatment devices as described below installed in the upper part of the furnace body. That is, an opening 30 in the ceiling of the furnace chamber is connected to an upper sealed chamber 43, and this upper sealed chamber 43 is connected to the υ1 gas processing device 45 through an opening 44 in the ceiling. This exhaust gas treatment device jq 45 burns hydrocarbon gas etc. generated in the Ik19 furnace, decomposes it into CO2°H2O and lower hydrocarbons, and oxidizes and purifies it. The heating parts 47 and 48 are opposed to each other, and the hydrocarbon gas generated in the lower furnace chamber 39 passes through this slit space 46. Primary air holes 49 provided in this device 45. The hydrocarbon gas is combusted and decomposed and purified by the air introduced through the secondary air holes 50.

Next, the activation gas generator 37 will be explained.

FIG. 4 shows an example of the configuration of this device. It basically consists of a liquid 52 in a sealed container 51, a porous absorbent body 53 such as a glass fiber cloth that is partially in contact with the liquid 52, and a heat generating heater 54 that is partially in contact with this absorbent body 63. be done. Gas from an inert gas cylinder 56, such as argon, phoneme, enters the device through an inlet 56 and enters the wick 53.
Steam generated by the action of the heater 54 and the heater 54 exits from the outlet 57 using the inert gas as a carrier and enters the furnace body 59.
supplied to 58 is a power controller section for the heater 54, and the steam supply per unit time can be arbitrarily controlled with high precision by power control.

Other activation gas generators include a method of bubbling an inert gas into a liquid kept at a high temperature in a container to obtain an oxidizing gas, and a method of generating an oxidizing gas using a high-temperature, high-pressure pot such as one that generates steam. Although other methods of obtaining gas are possible, by using the liquid vaporizer described above, the amount of vaporized vapor can be controlled linearly and accurately in proportion to the input power of the heater, as shown in Figure 6. Ideal as a gas generation source. However, FIG. 5 shows the case where water is used as the liquid, and the vertical axis is the amount of liquid water consumed per unit time.

Next, a method and process for carbonizing cloth using the activation furnace configured as described above will be explained with reference to FIG. The raw material cloth 60I''i enters the upper sealed chamber 43 from the inlet 62 by the driving row 961, passes through the roller 63 and enters the furnace chamber 39. Water vapor: The oxidizing gas 2 is supplied into the furnace chamber upward from the lower supply hole together with the gear inert gas.In other words, while passing through the furnace from the soil down, the cloth is The cloth is uniformly carbonized and activated by the dregs, and is led from the furnace bottom opening 31 to the lower sealed chamber 35.After the activation, the cloth is passed through an automatic winding device 64 provided in the lower sealed chamber.
It is wound up by. During activation, as described above, the inert gas inlet 40 of the lower sealed chamber 35 and the inert gas and gas curtains 41 and 42 keep the furnace chamber (d) at a low oxygen concentration, and the activation reaction occurs quickly. proceed optimally.

Optimum activation can be achieved by providing a plurality of activating gas supply holes in two positions depending on the width, size, etc. of the object to be activated, or by appropriately selecting the interval between them.

Furthermore, in the above embodiment, a method was described in which the material to be activated was moved from the top to the bottom, but there is also a method in which the raw material is sent upward from the lower sealed chamber 35, activated in the furnace chamber 39, and then rolled up in the upper part. It is possible.

The furnace of the present invention has excellent functions as a carbonization furnace,
It is also possible to introduce and use only the inert gas through the activation gas supply hole 36.

FIG. 6 shows the excellent features of the vertical carbonization activation method of the present invention.

As in the present invention, when the object 80 enters the furnace from above (the same applies to the case from below) and moves from the position of (a) (a) to the position (b) of FIG. The generated activating gases 81 and 82 react equally on both sides of the object to be activated 80, and the object that comes out of the furnace is exactly the same no matter where it is in the long length, resulting in no homogeneous reaction stratification. As mentioned above, in the case of a wide object to be activated, the activation gas 83 should be supplied evenly to both sides of the object.

On the other hand, as shown in Figure 6b), when moving the activated material 90 horizontally (from (a) to (b)), considering the temperature distribution in the furnace and the action of gravity, it is difficult to move the activated material 90 from above. Activating gas 92
．． It is difficult to uniformly supply 91 to both sides of the material to be activated 90, and the first product obtained by this method is unable to obtain excellent activated carbon because the activation progresses too much on either side.

Next, specific examples will be described.

Phenolic resin LM with a basis weight of 200.9/m'!
Cloth composed of fl (II] 100 cm, )
Activation is performed using the activation furnace shown in buoy 53. Furnace temperature is 900℃, furnace chamber length is 30cm + width is 1000m
, and the depth was 2°cm. For the activation gas, water was introduced into the apparatus shown in FIG. 4 to generate water vapor TO, which was then introduced into the furnace. The heater power of the steam generator is 1KW.
Nitrogen gas was used as the carrier gas at a rate of 201/min. The properties of the activated carbon cloth obtained in this example are shown in the following table.

In addition to the characteristics of the activated carbon fiber, the table also shows the capacitor characteristics when the activated carbon fiber of this example is used in the electric double layer capacitor devised by the present inventors. In this table,
Characteristics of activated carbon obtained using a conventional batch-type carbonization activation furnace.

A comparison of mass productivity will be posted.

Effects of the Invention As described above, the carbonization activation furnace of the present invention is suitable for continuous activation of long objects such as cloth, and has the following effects. (1) Since the distance between the furnace wall and the object to be activated is uniform and close, the temperature distribution is uniform. (2) It has a structure in which the activation gas reacts evenly and evenly with the object to be activated that moves continuously in the furnace. (3) Since it is a vertical furnace, the gas generated by the activation reaction is quickly discharged out of the system due to the draft effect. (4) When an exhaust gas combustion furnace is attached,
Hydrocarbon gas generated by activation is decomposed and purified.

As described above, the furnace of the present invention can supply industrially high-performance, homogeneous activated carbon cloth in large quantities, and its value is extremely high.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a conventional batch type carbonization activation furnace, Figure 2 is a conceptual diagram of producing activated carbon cloth using a batch furnace, and Figure 3 is a diagram of a conventional batch type carbonization activation furnace.
Figure 4 is a configuration diagram of a carbonization activation furnace according to an embodiment of the present invention, Figure 4 is a configuration diagram of an activation gas generation device, Figure 5 is a diagram showing the relationship between input power and water consumption of the activation gas generation device, FIG. 6 is a diagram explaining the superiority of the activation method according to the present invention over other methods. 30.31...opening, 32...furnace body, 33...
...Heating section, 35... Sealed chamber, 36... Activating gas supply hole, 37... Activating gas generator, 40
... Inert gas introduction hole, 46 ... Exhaust gas treatment device, 60 ... Raw material cloth. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3

Claims (1)

[Claims] (1) The heated furnace chamber has openings at the top and bottom, and carbonization activation is carried out from the top opening to the bottom opening, or from the bottom opening to the top opening. A carbonization activation furnace characterized in that a material is continuously moved through the furnace and the activation gas is supplied from at least three separate openings in the lower part of the furnace chamber. (2) The carbonization activation furnace according to claim 1, wherein the opening in the lower part of the furnace chamber is connected to a closed chamber capable of storing the carbonization-activated material or the carbonization-activated raw material. (3) The carbonization activation furnace according to claim 1, which has a structure that allows inert gas to flow in the direction of the object to be carbonized through either or both of the upper opening and the lower opening of the furnace chamber. (4) The carbonization activation furnace according to claim 2, wherein an inert gas is supplied to the sealed chamber. (6) The carbonization activation furnace according to claim 1, wherein the opening at the top of the furnace chamber is connected to an exhaust gas treatment device. (6) The carbonization activation furnace according to claim 5, wherein the exhaust gas treatment device comprises a pair of opposing heaters and a gas passage slit section between them. (7) The above-mentioned activation gas is supplied from a liquid vaporizer consisting of a liquid, a suction body in contact with the liquid, and a heat generating section on the upper part of the suction body, and an inert gas supply section. A carbonization activation furnace according to claim 1 constructed.