JP2006249801A - Asphalt recycling plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an asphalt recycling plant for preventing the occurrence of a fire by preventing the vaporized asphalt content in exhaust gas from sticking in a flue. <P>SOLUTION: A deodorizing furnace 11 is arranged on the downstream of the exhaust flue 7 of a drier 1, and a waste material is heated by supplying high temperature gas of the deodorizing furnace 11 to the drier 1 via a high temperature gas supply duct 5. A branch duct 14 formed by branching off the high temperature gas supply duct 5, is connected to the exhaust flue 7 on the downstream of the drier 1, so as not to condense the vaporized asphalt content in the exhaust gas by heightening the exhaust gas temperature in the exhaust flue 7 by introducing the high temperature gas into the exhaust flue 7. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an asphalt recycle plant that heats and recycles asphalt pavement waste material generated by road construction and the like.

When waste material is heated in an asphalt recycle plant dryer that heats and recycles asphalt pavement waste material (hereinafter referred to as “waste material”), the asphalt content is vaporized and led to the exhaust flue downstream of the dryer, but the exhaust gas temperature is around 200 ° C. Therefore, the vaporized asphalt content in the exhaust gas may be further condensed at the temperature near the flue inner wall, and may adhere to the inner wall of the exhaust flue. And, if the exhaust gas becomes temporarily high temperature, it may ignite, and if a fire is flying, it may ignite and cause a fire. As a means to prevent this asphalt from adhering to the exhaust flue, it is also possible to mix stone powder into the exhaust flue and coat it with stone powder so that it does not stick to the exhaust flue. (See Patent Document 1).
JP 60-230407 A

  However, as mentioned above, there is a problem that a large amount of stone powder is required to make the asphalt content non-sticky with stone powder, and maintenance is troublesome, and the flue for asphalt is a little easier. There has been a demand for the appearance of a method capable of preventing adhesion.

  This invention makes it a subject to provide the asphalt recycle plant which prevented generation | occurrence | production of a fire by preventing the vaporized asphalt part in waste gas from adhering in a flue in view of said point.

  In order to solve the above problems, the present invention provides an asphalt recycle plant according to claim 1, wherein a deodorizing furnace for thermally decomposing odorous components in exhaust gas is disposed downstream of an exhaust flue of a dryer for heating waste materials. The high-temperature gas derived from the deodorizing furnace is supplied to the dryer via a high-temperature gas supply duct to heat the waste material, while the end of the branch duct formed by branching the high-temperature gas supply duct is connected to the dryer outlet. It is connected to the exhaust flue and is characterized in that a part of the high temperature exhaust gas is led into the exhaust flue at the outlet of the dryer.

  Further, in the asphalt recycle plant according to claim 2, an exhaust gas temperature detected by an exhaust gas temperature detector disposed in the exhaust flue at the outlet of the dryer, wherein an opening adjusting damper is disposed in the branch duct. The opening adjustment control of the opening adjustment damper is performed based on the above.

  According to the asphalt recycle plant of claim 1 of the present invention, a deodorizing furnace for thermally decomposing odorous components in the exhaust gas is disposed downstream of the exhaust flue of the waste material heating dryer, and a high temperature derived from the deodorizing furnace. Gas is supplied to the dryer via a high-temperature gas supply duct to heat the waste material, while the end of the branch duct formed by branching the high-temperature gas supply duct is connected to an exhaust flue at the dryer outlet, Since a part of the exhaust flue is led into the exhaust flue at the outlet of the dryer, the exhaust gas temperature in the exhaust flue downstream of the dryer can be increased, making it difficult for the vaporized asphalt content in the exhaust gas to condense. Prevents the occurrence of fire by suppressing the adhesion of.

  According to the asphalt recycle plant of claim 2 of the present invention, an exhaust gas temperature detected by an exhaust gas temperature detector disposed in the exhaust flue at the outlet of the dryer, wherein an opening adjusting damper is disposed in the branch duct. Because the opening adjustment control of the opening adjustment damper is performed based on the above, the exhaust gas temperature in the exhaust flue can be controlled and maintained at a gas temperature that is difficult to condense asphalt, and the asphalt adheres to the exhaust flue. It can be suppressed and fire can be prevented.

  In the asphalt recycle plant according to claim 1 of the present invention, a deodorizing furnace for thermally decomposing odorous components in exhaust gas is disposed downstream of the exhaust flue of the dryer for heating the waste material, and a heat source for heating the waste material of the dryer. The high temperature gas of about 750 ° C. discharged from the deodorizing furnace is supplied to the dryer through the high temperature gas supply duct. A branch duct formed by branching the hot gas supply duct is connected to an exhaust flue at the outlet of the dryer. As a result, the exhaust gas of about 200 ° C. exhausted from the dryer and the high temperature gas of about 750 ° C. are combined so that the exhaust gas of about 350 ° C. flows in the exhaust flue downstream of the dryer, and the vaporized asphalt content in the exhaust gas It becomes difficult to condense, and it can prevent the occurrence of fire by suppressing the attachment of asphalt to the exhaust flue.

  In the asphalt recycle plant according to claim 2 of the present invention, an opening adjusting damper is disposed in a branch duct for introducing a high temperature gas into the exhaust flue of the dryer, and an exhaust gas is disposed in the exhaust flue at the outlet of the dryer. A temperature detector is provided. Then, the exhaust gas temperature detected by the exhaust gas temperature detector is taken into the damper opening adjuster, compared with a reference value preset by the damper opening adjuster, and based on the difference value, the opening adjustment Perform damper opening adjustment control. As a result, the temperature of the exhaust gas in the exhaust flue is controlled so that the vaporized asphalt content in the exhaust gas does not condense, and the occurrence of a fire can be prevented by suppressing the attachment of the asphalt content to the exhaust flue.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 in the figure is a known dryer for heating waste materials, and a cylindrical drum 2 having a large number of scraping blades (not shown) around its inner periphery is inclined on a machine base 3 in a freely rotatable manner. It is supported and rotated at a predetermined speed by a driving device (not shown). And the hot gas from the deodorizing furnace 4 mentioned later is sent in in the drum 2 via the hot gas supply duct 5, and was interposed downstream of the exhaust flue 7 connected with the discharge hopper 6 of the other end part of the drum 2. While the exhaust gas is sucked by the exhaust fan 8 and the high temperature gas flow passing through the drum 2 is maintained, the waste material discharged from the aggregate hopper (not shown) is supplied into the drum 2 via the belt conveyor 9. It is heated to the desired temperature while rolling down.

  A dust collector 10 that captures dust in the exhaust gas is disposed downstream of the exhaust flue 7, and a deodorization furnace 4 is disposed downstream of the dust collector 10 for burning and decomposing asphalt contained in the exhaust gas. Has been established. The exhaust gas that has passed through the deodorizing furnace 4 becomes a clean gas and is released from the chimney 11 into the atmosphere.

  The deodorizing furnace 4 is provided with a burner 12 for maintaining the furnace temperature at a predetermined value at one end, exposing the exhaust gas introduced into the furnace to a high temperature atmosphere, and burning and decomposing asphalt contained in the exhaust gas. Yes. The deodorizing furnace 4 controls the combustion amount of the burner 12 so that the temperature inside the furnace is maintained at a high temperature of, for example, approximately 750 ° C. or more so that the asphalt can be completely burned and decomposed, and the exhaust gas passes through the furnace. It is preferable to have a staying chamber 4a that takes at least 1 to 2 seconds or more to do so.

  A predetermined amount of the hot gas passing through the deodorizing furnace 4 is supplied to the dryer 1 through the hot gas supply duct 5 by controlling the degree of opening and closing of the damper 13. Further, the end of the branch duct 14 formed by branching the high temperature gas supply duct 5 is connected to the exhaust flue 7 at the outlet of the dryer 1, and a part of the high temperature gas passes through the branch duct 14 and is exhausted at the outlet of the dryer 1. It is led into the road 7 so as to merge with the exhaust gas of the dryer 1.

  An air volume adjusting damper 15 is disposed in the branch duct 14, and an exhaust gas temperature detector 16 is provided in the exhaust flue 7 near the outlet of the dryer 1. Further, a damper opening adjuster 17 for taking in the detection value of the exhaust gas temperature detector 16 is arranged, and the exhaust gas detection value taken in by the damper opening adjuster 17 is compared with a preset reference value, and the difference therebetween The opening adjustment control of the air volume adjusting damper 15 is performed based on the value amount.

  Reference numerals 18 and 19 denote heat exchangers for effectively using the exhaust gas heat of the exhaust gas having a high temperature of about 750 ° C. discharged from the deodorizing furnace 4, and the heat exchanger 18 is an exhaust flue. 7 raises the temperature of the exhaust gas introduced into the deodorizing furnace 4, and the heat exchanger 19 preheats the combustion air supplied from the combustion air supply fan 20 to the burner 12 of the deodorizing furnace 4. .

  Thus, when heating the waste material, first, the waste material is supplied to the dryer 1 via the belt conveyor 9, while the high temperature gas is supplied from the deodorizing furnace 4 to the dryer 1 via the high temperature gas supply duct 5. Heat to predetermined temperature. At this time, the supply amount of the high-temperature gas is controlled by adjusting the degree of opening and closing of the damper 13 so that the temperature of the heated waste material discharged from the drum 2 or the exhaust gas temperature becomes a preset value.

  Further, the opening degree of the air volume adjusting damper 15 is appropriately adjusted, and a high temperature gas of about 750 ° C. discharged from the deodorizing furnace 4 is led to the exhaust flue 7 at the outlet of the dryer 1 through the branch duct 14. Combine with the exhaust gas at about 200 ° C. At this time, in the case where the damper opening adjuster 17 is provided, the exhaust gas temperature in the exhaust flue 7 detected by the gas temperature detector 16 is taken into the damper opening adjuster 17, and a preset reference value, for example, 350 ° C. And the opening degree of the air volume adjusting damper 15 is controlled based on the difference value, and the temperature in the exhaust flue 7 downstream of the dryer 1 is maintained at about 350 ° C.

  Then, the exhaust gas derived from the dryer 1 is guided to the dust collector 10, and the dust content in the exhaust gas is captured by the dust collector 10, while the exhaust gas that has passed through the dust collector 10 is guided to the deodorizing furnace 4 and about 750 ° C. in the furnace. The asphalt remaining in the exhaust gas is completely burned and decomposed by exposure to a high temperature atmosphere. The high-temperature exhaust gas discharged from the deodorizing furnace 4 is lowered to about 400 ° C. through the heat exchangers 18 and 19 and discharged from the chimney 11 to the atmosphere.

  In this way, by supplying the high-temperature gas discharged from the deodorizing furnace 4 into the exhaust flue 7 downstream of the dryer 1 through the branch duct 14, the exhaust gas temperature in the exhaust flue 7 is set to a high temperature of about 350 ° C. As a result, the vaporized asphalt content in the exhaust gas becomes difficult to condense, and the asphalt content in the exhaust flue 7 can be suppressed to prevent the occurrence of a fire.

It is a schematic explanatory drawing which shows one Example of the asphalt recycle plant which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Dryer 4 ... Deodorizing furnace 5 ... High temperature gas supply duct 7 ... Exhaust flue 8 ... Exhaust fan 10 ... Dust collector 12 ... Burner 14 ... Branch duct 15 ... Damper for air volume adjustment 16 ... Exhaust gas temperature detector 17 ... Damper opening adjustment 18, 19 ... heat exchanger

Claims (2)

  A deodorizing furnace for thermally decomposing odor components in the exhaust gas is disposed downstream of the exhaust flue of the dryer for heating the waste material, and the high-temperature gas derived from the deodorizing furnace is supplied to the dryer via the high-temperature gas supply duct. While the waste material is heated, the end of the branch duct formed by branching the high temperature gas supply duct is connected to the exhaust flue at the outlet of the dryer so that a part of the high temperature exhaust gas is led into the exhaust flue at the outlet of the dryer. An asphalt recycle plant characterized by that.   An opening adjustment damper is disposed in the branch duct, and the opening adjustment control of the opening adjustment damper is performed based on the exhaust gas temperature detected by the exhaust gas temperature detector disposed in the exhaust flue at the outlet of the dryer. The asphalt recycle plant according to claim 1, which is performed.

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