JPH10111077A - Heater for drying chamber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the temperature inside a drying chamber constant by composing an exhaust pipe of a plurality of parallel pipes and enclosing each of the pipes with granular refractory solid material. SOLUTION: Eight exhaust pipes (lower side exhaust pipes) 10a that go out from a combustion furnace 3 are extended approximately horizontally and connected to a connection box 11 arranged on the other side of the combustion furnace. Eight exhaust pipes (upper side exhaust pipes) 10b are extended from the connection box 11 approximately horizontally and connected to the lower part of a chimney 9. A long and narrow iron container 12 is formed surrounding the lower side eight exhaust pipes 10a and the container 12 is packed with pebbles 13. A fan 16 is attached to the upper part of a frame body 15 to agitate the air inside a drying chamber 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying room heating apparatus suitable for drying wood and the like.

[0002]

2. Description of the Related Art In a conventional drying room heating apparatus, the heating power is adjusted by using an automatic control technique to keep the temperature of the drying room constant. However, when using wood chips or wood as fuel, automatic control cannot be used because the thermal power cannot be easily adjusted. Therefore, in a furnace that burns wood chips, there is a problem that a person has to adjust the heat power in a constant manner, and still, it is difficult to control the temperature.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to keep the temperature in a drying chamber substantially constant without using automatic control.

[0004]

According to the present invention, an exhaust pipe through which combustion gas exiting from a combustion furnace passes is routed into a drying chamber.
Then, the surrounding of the routed exhaust pipe is wrapped with a granular refractory solid such as pebbles. The fuel to be fired in the combustion furnace may be anything such as wood chips, coal, kerosene, and LP gas. For better heat conduction, the exhaust pipe is preferably made up of a plurality of parallel pipes, each of which is wrapped with a granular refractory solid.

[0005]

The exhaust pipe is heated by the combustion gas, and the granular refractory solid is heated by the heated exhaust pipe. The air in the drying chamber is kept at a high temperature by contacting the hot solid matter.

[0006] Refractory solids such as pebbles are
Since the specific gravity and the specific heat are large, and they withstand a considerably high temperature, a large amount of heat is accumulated in the high temperature exceeding 100 ° C., and there is still enough room to store the heat.

When the thermal power of the combustion furnace fluctuates, the temperature in the room immediately fluctuates without a heat storage body. However, since such a heat storage body (solid matter) exists in the drying furnace, the solid matter absorbs heat. It is possible to keep the inside of the drying chamber at a substantially constant temperature by dripping or discharging.

Further, when the fire of the combustion furnace is dropped,
As the heat accumulated by the solids is gradually released, the temperature in the drying chamber decreases very slowly, during which time,
Drying of the object to be dried proceeds. That is, during this time, unmanned operation becomes possible.

[0009]

An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a heating device 2 is installed at one corner of a drying chamber 1. As shown in FIG. 2, the heating device 2 includes a combustion furnace 3 for burning wood chips. The surroundings of the combustion furnace 3 are covered with refractory bricks, and wood chips introduced from a fire port 5 burn on the rostre 6. Combustion air is supplied from a firing port 5. The ash that has fallen below the rostral 6 is discharged from the ash outlet 7.

A chimney 9 stands right above the combustion furnace 3.
The chimney 9 and the combustion furnace 3 are connected by an exhaust pipe 10 routed in a drying chamber. That is, a total of eight (two rows of four rows) exhaust pipes (lower exhaust pipes) 10a that have exited the combustion furnace 3 are:
It extends substantially horizontally and is connected to a junction box 11 provided on the opposite side of the combustion furnace. Eight exhaust pipes (upper exhaust pipes) 10 b extend substantially horizontally from the connection box 11 and are connected to the lower part of the chimney 9. Each exhaust pipe 10 has a diameter of 120 mm and a length of 3600 mm.

An elongated iron container 12 is formed so as to surround these eight lower exhaust pipes 10a (see FIG. 3). Pebbles 13 are tightly packed in the container 12. In this embodiment, pebbles having a diameter of about 20 mm are used, and the total weight of the pebbles used is about 5 t.

A fan 16 is mounted on the upper portion of the frame 15 for stirring the air in the drying chamber 1. The wood to be dried is placed on a trolley and placed in the drying chamber 1.

With this configuration, when wood chips are burned in the combustion furnace 3, the high-temperature exhaust gas is discharged to the lower exhaust pipe 10a,
Through the junction box 11 and then through the upper exhaust pipe 10b, the chimney 9
Go out from. When the combustion in the furnace 3 is stabilized, the exhaust gas reaches about 800 ° C., and the exhaust pipe is exposed to such high-temperature exhaust gas, and the temperature rises. The lower exhaust pipe 10a transmits heat to the surrounding pebbles 13, and the pebbles 13 become hot and store a large amount of heat.

When the furnace is fired for one to two hours, the temperature of the pebbles rises to 300 to 400 ° C. and the upper exhaust pipe is
About ℃. The air in the drying chamber is heated in contact with the pebbles 13 (and the container 12 filled with pebbles) and the upper exhaust pipe 10b, and the temperature in the drying chamber rises to about 100 ° C.
At such a temperature, the moisture contained in the wood evaporates rapidly and enters the drying room, so that ventilation is performed using a fan (not shown) installed in the drying room.

[0015] The fire is stopped after about 10 hours, and left for about 12 hours. During this time, the pebbles 13 that have accumulated a large amount of heat maintain the temperature in the drying room, so that the room temperature drops only to about 60 to 70 ° C. The temperature of the pebbles is about 100 ° C even if it drops.

[0016]

As described above, according to the present invention, the exhaust pipe routed into the drying chamber is wrapped with the solid particles, so that the heat of the combustion gas can be stored in the solid materials. Since the amount is large, the drying chamber can be maintained at a substantially constant temperature even when the thermal power of the combustion furnace fluctuates. Further, even if the fire of the combustion furnace is dropped, since the solid material has residual heat, a predetermined temperature can be maintained in the drying chamber for a while, and the drying of the material to be dried proceeds during that time.

If the exhaust pipe is composed of a plurality of parallel pipes, and each of these pipes is wrapped with a granular refractory solid, the efficiency of heat transfer from the exhaust pipe to the solid is improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a drying chamber containing a heating device.

FIG. 2 is a longitudinal sectional view of a heating device.

FIG. 3 is a cross-sectional view of a heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drying room 2 Heating device 3 Combustion furnace 10 Exhaust pipe 13 Pebble (granular solid)

Claims (2)

[Claims] An exhaust pipe (10) through which combustion gas from a combustion furnace (3) passes is routed into a drying chamber (1), and a granular refractory solid (13) is wrapped around the exhaust pipe. ). A heating device for a drying room, wherein the heating device is wrapped in the drying room. 2. The exhaust pipe comprises a plurality of parallel pipes,
The drying chamber heating device of claim 1 wherein each of the tubes is wrapped with a granular refractory solid.