JP2012082064A - Dust air flow carrying device of exhaust gas treating device in waste disposal facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dust air flow carrying device that prevents pollution caused by leakage of hazardous gases and surrounding dust and is so designed as to dispense with much of its maintenance of the dust carrying device without restricting the layouts of each device that discharges dust.SOLUTION: In the dust air flow carrying device that conveys the dust in the air flows each discharged from a plurality of devices 3 to 6 disposed in the emission treating device of a waste disposal facility to a dust treating device through an air flow conveying pipe line 18, discharging valves 16 of devices 3 to 6 are coupled directly to the air flow conveying pipe line 18, each of the discharging valves 16 is connected to the air flow conveying pipe line 18 in series, the air flow conveying pipe line 18 generates the carrying air flow with a vacuum evacuation pump 13 that evacuates a vacuum tank 12, and the vacuum evacuation pump 13 discharges the exhaust gas into a dust collecting device 6 in the waste disposal treating device.

Description

  The present invention relates to a dust airflow conveying device that conveys dust generated in a waste treatment facility to the dust treatment facility.

  In a waste melting treatment facility, for example, a waste melting treatment facility, as shown in FIG. 3, the waste 11 is charged into the melting furnace 1 from the waste pit by the waste crane 10, and the charge is dried along with the descent in the furnace. -Preheated, pyrolyzed, combusted and melted, and discharged as a melt.

  The exhaust gas discharged from the upper part of the melting furnace 1 is combusted in the combustion chamber 3 of the exhaust gas treatment device, heat recovery is performed in the boiler 4, and the exhaust gas in the boiler 4 is cooled in the water spray type gas cooling tower 5, It is separated into solid and gas by the bag filter 6 and discharged from the chimney by the blower 7.

  Dust in the exhaust gas settles at the bottom of the combustion chamber 3, boiler 4, water spray type gas cooling tower 5 and bag filter 6, and the dust that has settled is cut out from each device 3-6 through a dust extraction valve 16. The dust cut-off valve 16 is provided with a rotary cut-off valve 16 having a double seal method or a seal function in order to prevent communication with the inside of the furnace.

  The dust discharged from the cut-off valve 16 is guided to the mechanical transfer type conveyor 20 and is collected and transferred to the dust storage hopper 21 of the dust processing facility. A screw conveyor or a scraper type conveyor is mainly used as the mechanical conveyance type conveyor 20. The dust transported to the dust storage hopper 21 is subsequently detoxified or granulated and returned to the waste melting furnace 1 and melted (see Cited Documents 1 to 3).

JP 2000-117224 A JP 2000-117223 A Japanese Patent Laid-Open No. 11-221545

  In a mechanical conveyance type conveyor used for conveying dust cut out from each device, a large number of conveyors are arranged from each device to a dust treatment facility to form a conveyance path. This is because the mechanical conveyance type conveyor requires linearity due to its mechanism. For this reason, since a mechanical conveyance system conveyor becomes a big constraint condition with respect to arrangement | positioning of the apparatus which discharges dust, and the space which these conveyor groups occupy becomes large, it has a big influence on installation cost.

  Moreover, when using a mechanical conveyance system conveyor, since it is comprised by many conveyor groups, the maintenance cost is also large. In addition, since maintenance is required, the deck surface is traversed, resulting in a traffic obstacle on the deck. Furthermore, since the casing is opened at the time of maintenance, there is a problem that the surroundings are contaminated with dust due to dust scattering.

  In addition, although the equipment that cuts out dust is normally operated at a negative pressure by an induction blower, it is open to the atmosphere from the dust extraction valve. There is a case where the amount increases temporarily from negative pressure to positive pressure, and at that time, there is a danger that harmful gas in the furnace leaks from the dust extraction valve and pollutes the environment.

  Therefore, the present invention prevents the leakage of harmful gas and contamination by surrounding dust in the waste treatment facility, does not restrict the arrangement of each device for cutting out dust, and does not significantly increase the maintenance of the dust transfer device. The dust airflow conveying device thus provided is provided.

  The invention of claim 1 of the present application is a dust airflow conveying device that conveys the dust cut out from each of a plurality of devices disposed in the exhaust gas treatment device of a waste treatment facility to the dust treatment facility by an airflow conveyance line, The cut-out valves of the respective devices are directly connected to the airflow conveyance pipes, and the cutout valves are connected in series to the airflow conveyance pipes.

  In the invention of claim 2 of the present application, an air introduction port is provided at the upstream end of the airflow conveyance pipe, and a vacuum tank is provided at the dust treatment facility side at the downstream end of the airflow conveyance pipe, which is conveyed by vacuum induction. It is characterized by generating an air flow.

  The invention of claim 3 of the present application is characterized in that the exhaust destination of the vacuum quotation vacuum pump for attracting the vacuum tank through the dust filter is in the dust collector of the waste treatment facility.

  The invention of claim 4 of the present application is characterized in that a suction air flow rate detection means and a flow rate control means are provided in the air inlet port portion at the upstream end of the airflow conveying pipeline.

  The invention of claim 5 of the present application is that in claim 4, a vacuum pressure detecting means is provided on the upstream side of the direct connection portion between the airflow conveying pipe and the dust extraction valve of each device, and air is introduced into the upstream end of the airflow conveying pipe. When the air flow rate in the mouth portion is reduced and the degree of vacuum is reduced, means is provided for temporarily stopping the dust cutting of the directly connected portion or reducing the dust cutting speed until the air flow rate and the vacuum degree are restored. .

  In the present invention, since the dust transport means is air transport, the air transport pipe can have a degree of freedom as compared to a mechanical transport conveyor in which the transport path is restricted from the top of the mechanism. Dust can be transported along the route. In addition, the problem of traffic obstruction on the deck is eliminated by air transport.

  In the present invention, the dust extraction valve of each device that cuts out dust and the air flow conveyance line are directly connected, the state of communication with the atmosphere is eliminated, and the evacuated exhaust is introduced into the waste treatment apparatus so that it can be used in the factory. Since it is sealed and completely closed without any emission, it is possible to prevent leakage of harmful gas in the furnace from the dust extraction valve, eliminating the problem of contamination by dust and harmful gas into the factory. Further, contamination due to dust scattering during maintenance can be prevented.

  In the present invention, since it is an airflow conveyance pipe and a discharge valve from each device is connected in series to one airflow conveyance tube, the connection of each device is simplified and the maintainability is improved.

  In the present invention, the vacuum attraction method is used as the air flow transportation method, so that air in the pipeline, dust flows back into the furnace or leaks through the dust extraction valve that may be generated in the case of the pressure and pressure feeding method. Can be prevented from being performed normally.

  Further, in the present invention, since the exhaust gas that has been evacuated is introduced into the waste treatment apparatus to eliminate the emission in the factory, environmental pollution can be prevented.

  Further, in the present invention, by constantly monitoring and controlling the flow rate and the degree of vacuum of the air that is the transport medium by the flow rate or the degree of vacuum detection means, it is possible to carry out stable air flow and prevent blockage. .

It is a figure which shows the example which applied the dust conveyance of this invention to the waste gasification melting equipment. It is sectional drawing which shows an example of the injector used by this invention. It is a figure which shows the example of the conventional ash conveyance of a waste gasification melting equipment.

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

  In FIG. 1, waste 11 is charged into a melting furnace 1 from a waste pit by a garbage crane 10, and the charged material is dried and preheated as the furnace descends, thermally decomposed, combusted and melted, and discharged as a melt. .

  The exhaust gas from the melting furnace 1 is processed by an exhaust gas processing device in which a combustion chamber 3, a boiler 4, a water spray type gas cooling tower 5 and a bag filter 6 are arranged. The exhaust gas is introduced into the combustion chamber 3 from the generated gas pipe 2 and burned by the combustion burner 8 into which the combustion air is blown by the combustion air fan 9, heat recovery is performed by the boiler 4, and the exhaust gas of the boiler 4 is water spray type gas After being cooled by the cooling tower 5, it is separated into solid and gas by the bag filter 6 and discharged from the chimney by the induction blower 7.

  The bottoms of the combustion chamber 3, the boiler 4, the water spray type gas cooling tower 5, and the bag filter 6 are each provided with a dust extraction valve 16 for cutting out dust that has fallen to the bottom. It is connected in series with the airflow conveyance pipe line 18.

  A general pipe material can be used for the airflow conveyance pipe 18, but a pipe material considering wear resistance is used for the curved pipe portion. If the waste treatment capacity is 150 to 200 t / day, the dust conveyance amount is 125 to 1170 kg / h, the air flow conveyance line 18 is about 50 A to 80 A, and the average solid-gas ratio is 2 to 3 kg / kg. Is done.

  The dust cut out from each of the devices 3 to 6 is sent to the air flow conveying pipe 18 by the injector 17 through the dust cutting valve 16. As shown in FIG. 2, in the injector 17, the cut out dust is mixed without staying in the conveying airflow, so that the pipe cross section is reduced immediately before the dust mixing portion, the airflow is speeded up, and the dust is accelerated.

  The air flow conveying pipe 18 is connected to a vacuum tank 12 provided in the vicinity of the dust treatment facility, and the dust carried by the air flow is stored in the vacuum tank 12. The pressure in the vacuum tank 12 is about −30 kPa. The vacuum tank 18 is evacuated by the vacuum pump 13 through the filter 12 a and exhausted into the bag filter 6.

  On the other hand, the air for conveyance is taken in from the air intake port 15 provided at the upstream end of the airflow conveyance pipeline 18. The in-pipe flow velocity of the conveying air is set to about 20 to 25 m / s. In this portion, an air flow meter (FI), an air flow rate adjustment indicator (FIC), and an air flow rate adjustment valve 19 adjusted by the air flow rate adjustment indicator (FIC) are provided. The air flow rate adjusting valve 19 is controlled in opening degree so that a constant amount of air flows regardless of the change in the pipe pressure loss due to the change in the dust concentration.

  Further, when the amount of dust cut out from each device 3 to 6 temporarily increases, the blockage of the airflow conveyance line 18 becomes a problem, but when the airflow conveyance line 18 tends to be blocked, It can be detected by a decrease in the air flow rate.

  In addition, assuming that the airflow conveyance pipe line 18 is blocked, a vacuum pressure detector (PI) 22 is provided on the upstream side of the injector 17, and when the air flow rate is reduced and any of the vacuum degrees is reduced, It is possible to prevent clogging of the airflow conveyance line 18 by temporarily stopping dust cutting immediately downstream of the vacuum pressure detector (PI) 22 that has detected a decrease in the degree of vacuum or by reducing the dust cutting speed. When reducing the dust cutting speed, if the vacuum level rises according to the degree of vacuum of the vacuum pressure detector (P2) immediately upstream of the dust cutting valve that reduces the cutting speed, the cutting speed is increased and the vacuum level is increased. If it falls, it can control to reduce the cutting-out speed.

  Although the airflow conveyance line 18 is configured for each furnace, it can be joined from another furnace in the middle. Further, a hose can be connected to the air intake port 15 to be used for vacuum cleaning while the furnace is stopped.

1: Melting furnace 2: Generated gas pipe 3: Combustion chamber 4: Boiler 5: Water spray type gas cooling tower 6: Bag filter 7: Induction fan 8: Combustion burner 9: Combustion air fan 10: Waste crane 11: Waste 12: Vacuum tank 13: Vacuum pump 14: Dust extraction valve 15: Air suction port 16: Dust extraction valve 17: Injector 18: Air flow conveyance line 19: Suction air flow adjustment valve 20: Machine conveyance type conveyor 21: Dust storage hopper 22: Vacuum pressure detector

Claims (5)

  A dust airflow conveying device that conveys dust cut out from a plurality of devices disposed in an exhaust gas treatment device of a waste treatment facility to a dust treatment facility by an airflow conveying pipe, A dust airflow conveyance device for an exhaust gas treatment apparatus in a waste treatment facility, wherein the cutout valves are directly connected to each other, and the cutout valves are connected in series to an airflow conveyance pipe line.   An air inlet is provided at the upstream end of the airflow conveyance pipeline, and a vacuum tank is provided at the dust treatment facility side at the downstream end of the airflow conveyance pipeline, which generates a conveyance air flow by vacuum induction. The dust airflow conveying apparatus of the exhaust gas treatment apparatus in the waste treatment facility according to claim 1.   The dust of the exhaust gas treatment apparatus in the waste treatment facility according to claim 2, wherein the exhaust destination of the vacuum citation vacuum pump that attracts the vacuum tank through the dust filter is in the dust collector of the waste treatment facility. Airflow transfer device.   4. The dust of the exhaust gas treatment apparatus in the waste treatment facility according to claim 3, wherein a suction air flow rate detecting means and a flow rate control means are provided at an air inlet port portion at an upstream end of the air flow conveying pipe. Airflow transfer device.   A vacuum pressure detection means is provided upstream of the direct connection between the airflow transfer pipe and the dust extraction valve of each device, and the air flow rate at the air inlet at the upstream end of the airflow transfer line is reduced and the degree of vacuum is reduced The exhaust gas treatment in the waste treatment facility according to claim 4, further comprising means for temporarily stopping the dust cutting of the directly connected portion or reducing the dust cutting speed until the air flow rate and the degree of vacuum are recovered. Dust airflow conveying device of the device.

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