JP2006206810A - Method for operating induction-heating type dry distillation furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve treating capacity of a dry distillation furnace by eliminating the need to "wait until pressure difference between the dry distillation furnace and a charging hopper becomes zero" which is a waiting time after the charging of to-be-dry-distilled matter until the charging of next to-be-dry-distilled matter. <P>SOLUTION: The need to "wait until pressure difference between the dry distillation furnace and a charging hopper becomes zero" is eliminated by providing a bypass connecting the dry distillation furnace and the charging hopper, and controlling the opening/closing of the bypass so as to reduce the pressure difference between the inside of the dry distilling furnace and the inside of the charging hopper. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an induction heating type carbonization furnace that performs carbonization treatment of a waste containing, for example, a polymer compound, and more particularly to an induction heating type carbonization furnace that facilitates continuous charging of a material to be dried into the furnace.

  For example, Patent Document 1 discloses a batch processing induction heating type distillation furnace. FIG. 2 is an explanatory view showing an example of a conventional configuration of this type of carbonization furnace. In FIG. 2, a dry distillation tank 2 made of a magnetic material (iron) is installed in a closed dry distillation furnace main body 1 that forms an inert gas atmosphere, and a heating coil 3 is disposed on the outer periphery of the dry distillation furnace main body 1. . The heating coil 3 is excited by an excitation power source 4 and induction heats the dry distillation tank 2. A dry distillation furnace main body 1 made of a heat insulating material is provided with a furnace bottom 6 that can be opened and closed. A charging hopper 8 is provided above the furnace lid 5 to input a material to be dried 7 into the dry distillation tank 2. Is provided with a discharge tray 9 for receiving the dry matter 7 discharged from the dry distillation tank 2. An inert gas (nitrogen) from an inert gas tank 10 or an inert gas generator is introduced into the furnace through an opening / closing valve 11, and dry distillation gas generated in the furnace is discharged through an opening / closing valve 12 to an exhaust gas treatment facility 13. To be discharged.

  Further, in FIG. 2, nitrogen in the inert gas tank 10 is supplied to the charging hopper 8 via the opening / closing valve 20, and the internal gas of the charging hopper 8 is discharged to the exhaust gas treatment facility 13 via the opening / closing valve 21. It has become. An oxygen concentration meter 22 for detecting the internal oxygen concentration is attached to the main body of the carbonization furnace. An oxygen concentration meter 23 and an oxygen concentration meter 24 for detecting the internal oxygen concentration are also attached to the charging hopper 8. The charging hopper 8 has an inlet 14 and an outlet 15 for the dry distillation object on the upper and lower sides, and the inlet 14 and the outlet 15 are hermetically closed by an upper lid 16 and a bottom lid 17 that can be opened and closed, respectively. ing. The upper lid 16 is sealed by a removable and water-sealed seal mechanism 18 or packing, while the hinge-type bottom lid 17 is close to the dry distillation tank 2 so that the temperature becomes high, so that a gasket seal structure is adopted, and dry distillation is performed. In order to prevent the to-be-dried material 7 from being placed in a shelf-suspended state in the charging hopper 8 when the material is charged, it is an electrically driven type that can adjust the opening degree. The discharge port 15 of the charging hopper 8 is airtightly connected to the inside of the furnace by a charging chute 19.

  To operate the carbonization furnace shown in FIG. 2, when a predetermined amount of the material 7 to be dried is stored in the charging hopper 8, the upper lid 16 is closed and the charging hopper 8 is sealed. Next, the open / close valve 20 and the open / close valve 21 are controlled to supply nitrogen into the charging hopper 8. During the supply of nitrogen, the oxygen concentration in the hopper is controlled by the oxygen concentration meter 23 and the oxygen concentration meter 24, and nitrogen replacement is performed until the oxygen concentration meter becomes a predetermined concentration or less. The combustion limit value in the dry distillation furnace is mixed into the mixed gas of combustible gas and nitrogen. Therefore, the combustion limit value is evaluated based on the upper limit value of the combustion limit. A 4-fold diluted oxygen concentration is generally used. For example, in dry distillation of used beverage cans, when this value is calculated from the combustible gas components obtained by experiments, the oxygen concentration at the upper limit of combustion becomes 12%, which is a value diluted four times. Needs to be replaced with nitrogen to an oxygen concentration of 3% or less.

Further, the gas discharged from the charging hopper 8 (air and nitrogen in the hopper) is discharged to the exhaust gas treatment facility 13 by controlling the open / close valve 21. At this time, nitrogen is similarly substituted in the carbonization furnace, and the bottom lid 17 of one charging hopper 8 is opened in a state where the oxygen concentration in the furnace measured by the oxygen concentration meter 22 is 3% or less, and the carbonization is performed. The material 7 is put into the carbonization tank 2. In the dry distillation furnace, the pressure rises due to volume expansion due to the temperature rise of the gas flowing from the input hopper 8 together with the dry matter, evaporation of moisture contained in the dry matter 7, and the like. For this reason, the other charging hopper inputs the material to be dried after confirming that the pressure in the carbonization furnace has returned to a predetermined pressure.
Next, the dry distillation tank 2 is induction-heated by the heating coil 3, and after the dry distillation object 7 reaches a predetermined temperature, the dry distillation treatment is performed by holding for a certain time. The to-be-distilled product 7 which has completed the dry distillation is discharged to the discharge tray by opening the furnace bottom 6. When discharging the to-be-distilled material 7 from the dry distillation furnace main body 1, all the combustible gas generated in the furnace is processed by the exhaust gas treatment equipment 13, so that the combustible gas is burned even if the furnace bottom 6 is opened. Never do. When the to-be-dried product 7 is discharged, the furnace bottom 6 is closed, and nitrogen substitution in the dry distillation furnace is performed for the next preparation. When the nitrogen substitution in the carbonization furnace is completed and the charging hopper 8 has completed the storage of the carbon dioxide 7 and the nitrogen substitution, the carbon dioxide 7 is introduced into the carbonization furnace and the next batch process is performed.
Japanese Patent Application No. 2003-308482

The inside of the hopper to be charged is maintained at atmospheric pressure, and a differential pressure between the pressure in the dry distillation furnace and the pressure in the hopper is generated in the hopper bottom lid 17. Due to the differential pressure, the bottom lid is pushed in the closing direction and cannot be opened. As described above, the hopper to be charged later must be charged after waiting until the pressure difference between the dry distillation furnace and the charging hopper disappears, and the efficiency of the continuous processing is deteriorated.
The present invention has been made in order to solve the above-mentioned problem. When the material to be dried 7 is charged from the charging hopper 8 to the carbonization tank 2, the pressure difference between the charging hopper 8 and the carbonization furnace is adjusted, It is an object to shorten the time required for charging 7 and improve the continuous processing capability.

As means for solving the above-described problems, the present invention is configured as follows.
In an operation method of an induction heating type carbonization furnace in which a carbonization product is charged into a carbonization tank induction-heated in a furnace in an inert gas atmosphere through a plurality of charging hoppers, and the carbonization product is subjected to carbonization treatment in the carbonization tank. Then, after putting the material to be distilled from any charging hopper into the carbonization tank and the pressure in the carbonization furnace is higher than the pressure in the other charging hopper, the material to be dried is continuously fed from the other charging hopper to the carbonization tank. A method of charging dry matter from the charging hopper to the dry distillation tank after adjusting a pressure difference in the charging hopper and a pressure in the carbonization furnace when charging.

  According to the present invention, there is no pressure difference between the pressure inside the charging hopper and the pressure inside the carbonization furnace after charging the material to be dried. This eliminates the possibility of continuous processing.

The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing an example of a configuration of a dry distillation furnace in an embodiment of the invention. In FIG. 1, the same reference numerals are used for portions corresponding to those in the explanatory view showing an example of the configuration of the conventional dry distillation furnace shown in FIG. 2.
In FIG. 1, the closing hopper 8 and the closing chute 19 are connected by a bypass circuit 30 and an opening / closing valve 31 is attached. The other structure of the carbonization furnace of FIG. 1 is the same as the structure of FIG.
The steps of the carbonization treatment by the carbonization furnace of FIG. 1 are as follows. When a predetermined amount of the material 7 to be dried is stored in the charging hopper 8, the upper lid 16 is closed to make the charging hopper 8 sealed. Next, the open / close valve 20 and the open / close valve 21 are controlled to supply nitrogen into the charging hopper 8. During the supply of nitrogen, the oxygen concentration in the hopper is controlled by the oxygen concentration meter 23, and nitrogen substitution is performed until the oxygen concentration becomes a predetermined concentration or less. Similarly, the other charging hopper stores dry matter and performs nitrogen substitution.

Gas discharged from the charging hopper 8 (air and nitrogen in the hopper) is discharged to the exhaust gas treatment facility 13 by controlling the open / close valve 21. At this time, the carbonization furnace body 1 is similarly purged with nitrogen, and the open / close valve 31 of the bypass circuit 30 is opened and closed while the oxygen concentration in the carbonization furnace body 1 measured by the oxygen concentration meter 22 is 3% or less. The same pressure is set in the furnace and the charging hopper 8. Thereafter, the bottom lid 17 of the charging hopper 8 is opened, and the dry distillation object 7 is charged into the dry distillation tank 2. After the charging, the bottom lid 17 and the opening / closing valve 31 are closed, and the opening / closing valve 33 of the bypass circuit 32 is similarly opened and closed to adjust the pressure. Then, the bottom lid 17 is opened and the dry matter 7 is charged.
Next, the carbonization tank 2 is induction-heated by the heating coil 3, and after the material 7 to be dried reaches a predetermined temperature, the carbonization process is performed by holding for a certain time. The to-be-distilled product 7 having been subjected to dry distillation is discharged to the discharge tray 9 by opening the furnace bottom 6. When the to-be-distilled material 7 is discharged, the furnace bottom 6 is closed, and nitrogen in the dry distillation furnace is replaced for the next preparation. After the nitrogen replacement, the charging hopper 8 also inputs the dry distillation object 7 into the dry distillation furnace when the storage of the dry distillation object 7 and the nitrogen replacement are completed, and performs the next batch processing.

According to the dry distillation treatment, the dry distillation object 7 can be input by opening the bottom lid 17 of the input hopper 8 regardless of the pressure in the dry distillation furnace. Even when the dry distillation object 7 is charged from a plurality of charging hoppers, even if the pressure in the dry distillation furnace increases due to the first charging, the next charging waits for the pressure in the dry distillation furnace to drop to a predetermined value. Can be thrown in.
In the above description of the embodiment, the inside of the carbonization furnace and the charging hopper are adjusted to have the same pressure. However, the same pressure is not necessarily required, and the bottom cover 17 of the charging hopper 8 can be opened without difficulty. What is necessary is just to adjust a pressure to a pressure difference.

Explanatory drawing which shows an example of a structure of the dry distillation furnace of this invention Explanatory drawing which shows an example of the structure of the conventional dry distillation furnace

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbonization furnace body 2 Carbonization tank 3 Heating coil 4 Excitation power supply 5 Furnace lid 6 Furnace bottom 7 To-be-distilled material 8 Input hopper 9 Discharge tray 10 Inert gas tank 11, 12, 20, 21, 31, 33 Open / close valve 13 Exhaust gas treatment equipment 14 Loading port 15 Discharge port 16 Upper lid 17 Bottom lid 18 Sealing mechanism 19 Input chute 22, 23, 24 Oxygen concentration meter 30, 32 Bypass circuit

Claims (1)

In an operation method of an induction heating type carbonization furnace in which a carbonization product is charged into a carbonization tank induction-heated in a furnace in an inert gas atmosphere through a plurality of charging hoppers, and the carbonization product is subjected to carbonization treatment in the carbonization tank. ,
After putting the material to be distilled from any charging hopper into the carbonization tank and the pressure in the carbonization furnace is higher than the pressure in the other charging hopper, the material to be dried is continuously charged from the other charging hoppers to the carbonization tank. When the pressure in the charging hopper and the pressure difference in the dry distillation furnace is adjusted, the to-be-dried material is charged into the dry distillation tank from the charging hopper,
A method of operating an induction heating type carbonization furnace characterized by the above.

Images