JP7192733B2 - Heavy metal concentration measuring device and method, fly ash processing device having heavy metal concentration measuring device - Google Patents

Description

The present invention relates to a heavy metal concentration measuring device and method for measuring the concentration of heavy metals in fly ash discharged from an incineration facility, and to a fly ash processing apparatus having the heavy metal concentration measuring device.

Ash, including fly ash, is contained in the exhaust gas emitted when waste is incinerated in an incinerator such as a waste incinerator. This fly ash contains so-called heavy metals such as lead, copper, cadmium, and chromium, and since these heavy metals are harmful if discharged as they are, these heavy metals should be treated appropriately using chemicals. There is a need.

By the way, chemicals for treating these heavy metals are very expensive, but since the amount of heavy metals in fly ash was unknown, there is a tendency to use more chemicals than necessary to treat heavy metals. There was a need for improvement measures. Therefore, as means for solving this problem, a technique disclosed in Patent Document 1 has been proposed. According to this Patent Document 1, a side wall of a vertical chute-shaped ash moving path through which ash descends is connected to a take-out passage portion that opens and extends rearward (laterally), and dish-shaped ash is placed in the take-out passage portion. The container for collecting ash is provided so as to be movable back and forth, the container for collecting ash is moved forward into the ash transfer route, and the descending ash is collected within the ash transfer route. The ash is moved backward from the collection position in the movement path to the measurement position in the removal passage, and is stored in the ash collection container at the measurement position by the X-ray measurement means provided on the upper wall position of the removal passage at this measurement position. The concentration of heavy metals in the collected ash is to be measured.

In the take-out passage, a downward ash discharge passage is branched at a position further rearward than the measurement position. The fly ash is dropped by tilting the ash collection container and discharged from the ash discharge passage.

JP 2011-133227

However, in the technique disclosed in Patent Document 1, in order to collect and discharge ash (fly ash) in the chute-shaped ash movement path, the extraction passage part for ash collection is directed laterally from the ash movement path. At the same time, an ash discharge passage must be branched from the removal passage, and the ash collection container must be moved to a collection position within the ash transfer route, a measurement position, and a discharge position in the ash discharge passage. Therefore, the drive unit becomes complicated, and the structure of the whole device is not simple and the size is increased. There is also the problem that the temperature of the fly ash changes (falls in temperature) during movement, causing the fly ash to adhere to the collection container or the collection container to easily corrode.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances. An object of the present invention is to provide an ash processing apparatus.

The above problems are solved by a heavy metal concentration measuring device and method according to the present invention, and a fly ash processing apparatus having a heavy metal concentration measuring device.

The heavy metal concentration measuring device of the present invention is installed in the fly ash transfer pipeline of the fly ash discharged from the incineration facility, collects the fly ash moving in the fly ash transfer pipe, and measures the heavy metal concentration in the collected fly ash. A heavy metal concentration measuring device that measures the and a measurement unit that measures at a position in the fly ash transfer pipeline.

In the present invention, it is preferable to further include a collected fly ash removing section for removing the collected fly ash received by the collected fly ash receiving section from the collected fly ash receiving section.

In the present invention, the collected fly ash removal section may be a gas injection body that injects gas to the collected fly ash receiving section to scatter and remove the collected fly ash from the collected fly ash receiving section.

In the present invention, the measuring unit and the collected fly ash receiving unit are supported by a movable support, and the movable support positions the collected fly ash receiving unit at one of the fly ash collecting position and the standby position. The heavy metal concentration of the collected fly ash at the collected fly ash receiving unit can be measured by the measuring unit at the collecting position.

In the present invention, it is preferable that the movable support forms a protective case, accommodates the measurement unit inside, and positions the collected fly ash receiving unit on the outer surface.

In the present invention, it is possible to provide measurement frequency setting means for setting the measurement frequency of the heavy metal concentration of the collected fly ash measured by the measurement unit.

The fly ash processing apparatus of the present invention is a fly ash processing apparatus having the heavy metal concentration measuring device according to the present invention, wherein the fly ash discharged from the fly ash transfer pipe is supplied with a heavy metal elution prevention agent. The amount of the heavy metal elution preventing chemical supplied from the heavy metal elution preventing chemical supplying means is controlled based on the concentration of heavy metals contained in the collected fly ash measured by the elution preventing chemical supplying means and the measuring unit. and drug amount control means.

In the heavy metal concentration measuring method of the present invention, the fly ash discharged from an incineration facility is collected by using a heavy metal concentration measuring device installed in the fly ash transfer pipe and collecting the fly ash moving in the fly ash transfer pipe. , a heavy metal concentration measuring method for measuring the concentration of heavy metals in collected fly ash, wherein a collected fly ash receiving part is positioned in a fly ash transfer pipe, receives fly ash at the collected fly ash receiving part, and collects The heavy metal concentration of the collected fly ash received by the fly ash receiving section is measured by a measurement section at a position within the fly ash transfer pipe.

According to the present invention, it is possible to provide a heavy metal concentration measuring device and method capable of measuring the concentration of heavy metals contained in fly ash with a simple configuration, and a fly ash processing apparatus having a heavy metal concentration measuring device.

1 is a schematic configuration diagram showing a fly ash processing apparatus provided with a heavy metal concentration measuring device and peripheral devices as an embodiment of the present invention; FIG. FIG. 2 is a partial cross-sectional view showing in detail the heavy metal concentration measuring device in FIG. 1;

In FIG. 1, the fly ash processing apparatus as the present embodiment includes a heavy metal concentration measuring device (hereinafter referred to as a “measuring device”) 1 provided in a fly ash moving pipe 2 forming a fly ash moving path, and a measuring device 1 It has various peripherals for fly ash treatment connected to it. The measuring device 1 collects fly ash descending through the fly ash transfer pipe 2 and measures the concentration of heavy metals in the collected fly ash (hereinafter referred to as "collected fly ash"). In this embodiment, the measurement of the heavy metal concentration by the measuring device 1 is performed periodically (for example, every hour) at preset time intervals. The peripheral devices include a control device 5, a heavy metal elution prevention chemical storage tank 7, and a pump 8, which will be described later. Operate. It should be noted that the pump 8 can be replaced with a type that naturally flows down via a container provided with a valve. In other words, the amount of the heavy metal elution preventing agent contained in the container may be adjusted while adjusting the opening of the valve. Further, the measuring device 1 will be described later in detail based on FIG. 2, and prior to the description, peripheral devices will be described.

The fly ash transfer pipe 2 to which the measuring device 1 is attached has the shape of a vertical chute and is connected to the lower part of the fly ash receiver 3 . For example, the flue gas emitted from a waste incinerator (not shown) contains fly ash, and the fly ash is an economizer device, a temperature reducer, and a dust collector (all shown in the figure) connected to the incinerator. (not shown), and dropped and discharged from at least one of the devices. The fly ash receiving part 3 is designed to receive the dropped and discharged fly ash. The fly ash moves downward from the fly ash receiver 3 through the fly ash transfer pipe 2 . At the lower end of the fly ash transfer pipe 2, a fly ash conveyor 4 is provided for conveying and discharging the fly ash that descends from the fly ash transfer pipe 2 and is accumulated.

A control device 5 is connected to the measuring device 1 for receiving a measured value from the measuring device 1 and transmitting a command signal for controlling the measuring device 1 and the pump 8 based on the measured value. The control device 5 provides a chemical amount control means (not shown) for issuing a command signal to the pump 8 connected to the heavy metal elution preventing chemical storage tank 7, which will be described later, to determine the amount of chemical to be supplied to the kneading device 6, which will be described later. have. If the heavy metal elution preventing agent is stored in a container equipped with a valve instead of the pump 8, the opening of the valve is adjusted based on this command signal.

A kneading device 6 is provided below the fly ash conveyor 4 provided at the lower end of the fly ash transfer pipe 2 . While receiving the ash, the heavy metal elution preventing agent supplied from the heavy metal elution preventing agent storage tank 7 through the pump 8 is received, and the fly ash and the heavy metal elution preventing agent are kneaded and discharged as a kneaded product. This chemical for preventing heavy metal elution is a chemical that prevents elution of heavy metals in fly ash from fly ash. The pump 8 operates in response to a command signal from the control device 5 and sends the heavy metal elution preventing agent to the kneading device 6 in an amount based on the heavy metal concentration measured by the measuring device 1 . In this embodiment, the heavy metal elution preventing agent storage tank 7 and the pump 8 constitute heavy metal elution preventing agent supplying means.

A kneaded material conveyor 9 for receiving and conveying the kneaded material discharged from the kneading apparatus 6 is provided below the kneading apparatus 6, and a pit as a storage tank for receiving the kneaded material is provided below the kneaded material conveyor 9. 10 are provided.

Next, the measuring device 1 shown in FIG. 1 will be explained based on FIG.

As can be seen in FIG. 2, the measuring device 1 is housed in a storage chamber 21 provided extending outward from a window 2A formed in the side wall of the fly ash transfer pipe 2 in the front-rear direction (in FIG. 2). It has a protective case 11 as a movable support that can reciprocate in the lateral direction), and a plate-shaped collected fly ash receiving part 12 is arranged on a part of its upper wall, and a measuring part 13 is installed inside. It is contained. Further, on the end wall of the protective case 11, a cooling air inlet 14 for feeding cooling air A from an air source (not shown) into the protective case 11 and an air inlet 14 for feeding air B after cooling are provided. and a sending unit 15 . The accommodation chamber 21 accommodates the protective case 11 and has a seal 21A between itself and the protective case 11 . The cooling air supply unit 14 has an opening/closing function, and is opened/closed by a command from the control device 5 .

Although the material of the protective case 11 itself is not limited, it is preferable to use aluminum, stainless steel, or the like in consideration of corrosion resistance. Moreover, it is preferable that the structure be such that the inside of the case is airtight. On the other hand, the collected fly ash receiving part 12 is made of a material that transmits X-rays or the like emitted from the measuring part 13 in order to measure the heavy metal concentration of the collected fly ash on the collected fly ash receiving part 12. For example, Made of resin. The collected fly ash receiving part 12 has a seal 21A between the wall of the fly ash transfer pipe 2 and the outer surface of the protective case 11, so that when the protective case 11 reciprocates in the storage chamber 21, the seal 21A is present. , the airtightness between the protective case 11 and the fly ash transfer pipe 2 is maintained.

The measurement unit 13 includes a transmission unit (not shown) that emits radiation P such as X-rays toward the collected fly ash receiving unit 12, and the X-rays pass through the collected fly ash receiving unit 12 and enter the collected fly ash. and a receiver (not shown) for receiving reflected rays Q reflected by heavy metals. The measurement unit 13 also includes an output unit (not shown) that converts the reflected dose received by the receiving unit into a heavy metal concentration, obtains and outputs the measured value, and controls the measured value from this output unit. Send to device 5. The measuring unit 13 also has a temperature measuring unit (not shown) inside the protective case 11 for measuring the temperature inside the protective case 11 . The temperature measurement unit is connected to the control device 5 and transmits to the control device 5 a signal (temperature signal) regarding the temperature inside the protective case 11 measured by the temperature measurement unit.

The measuring device 1 has a drive unit 16 that reciprocates the protective case 11 in the front-rear direction. The drive unit 16 has a cylinder body 16A attached to a member such as an apparatus housing at a fixed position, and a rod 16B that is moved in and out of the cylinder body 16A. A pin joint 16C is provided at the tip of the rod 16B. The mounting member 16D is fixed and attached to the upper surface of the protective case 11. As shown in FIG. Therefore, the protection case 11 reciprocates in the storage chamber 21 extending from the fly ash transfer pipe 2 by the operation of the driving portion 16 . This reciprocating motion consists of a collection position (advance position) where the collected fly ash receiving portion 12 provided on the upper surface of the protective case 11 enters the fly ash transfer pipe 2 (advance position), and a position where the collected fly ash receiving portion 12 moves into the fly ash transfer pipe. It is performed between the standby position (retracted position) outside the road 2 , that is, inside the storage chamber 21 . FIG. 2 shows a state in which the collected fly ash receiving part 12 is in the collecting position within the fly ash transfer pipe 2 . The drive unit 16 for reciprocating the protective case 11 between the sampling position and the standby position is operated by a command signal from the control device 5 .

Furthermore, the measuring device 1 has a collected fly ash removing unit 22 for scattering and removing the collected fly ash from the collected fly ash receiving unit 12 after measuring the heavy metal concentration. The collected fly ash removal unit 22 is provided in a recess 2B sunk from the side wall of the fly ash transfer pipe 2 at a position above the accommodation chamber 21, and has a jet nozzle-like gas injection that ejects gas such as air. formed as a body. In this embodiment, the collected fly ash removing unit 22, which is a jet nozzle connected to an air source, receives a command signal from the control device 5 and supplies gas such as air to the collected fly ash receiving unit 12 at the collecting position. It is designed to be directed and jetted. When the measurement is completed, the collected fly ash on the collected fly ash receiving part 12 is blown away by the injection of gas such as air and scatters in the fly ash transfer pipe 2, and is scattered on the collected fly ash receiving part 12. removed from

Next, the procedure for measuring the concentration of heavy metals in fly ash and the procedure for treating fly ash based on the measurement in such an embodiment apparatus will be described.

In the fly ash transfer pipe 2, fly ash transferred from at least one of an economizer device, a temperature reducing device, and a dust collector that have treated the exhaust gas from the incinerator to the fly ash receiving portion 3 is transferred to the fly ash receiving portion 3. It descends in the fly ash transfer pipe 2 via.

The drive unit 16 operates when receiving a command from the control device 5 to drive the rod 16B and advance the protective case 11 toward the inside of the fly ash transfer pipe 2 via the mounting member 16D. The protective case 11 temporarily stops at the forward position. This forward position serves as a collection position, and a plate-shaped collected fly ash receiving portion 12 attached to the upper surface of the protective case 11 receives the fly ash during its downward movement within the fly ash transfer pipe 2 . After a predetermined period of time has passed, the measuring unit 13 starts measuring when or before the collected fly ash on the collected fly ash receiving unit 12 reaches a predetermined amount or more. For example, X-rays or the like are emitted from the transmitter of the measurement unit 13 as radiation P toward the collected fly ash receiving unit 12, and the radiation P passes through the collected fly ash receiving unit 12 made of resin and into the collected fly ash. hits heavy metals and is reflected. The measuring unit 13 receives the reflected radiation Q at the receiving unit, converts the reflected radiation dose into a heavy metal concentration, and calculates the measured value. This measured value is sent to the control device 5 together with the temperature signal from the temperature measuring section.

When the controller 5 receives a signal about the measured value from the measuring unit 13 of the measuring device 1, the controller 5 appropriately displays the measured value itself, judges that the measurement is finished, and collects a command signal for injecting air. It is transmitted to the fly ash removal unit 22 . As a result, air is injected from the collected fly ash removing unit 22, and the measured collected fly ash placed on the collected fly ash receiving unit 12 is blown away by the air and removed. The blown collected fly ash scatters in the fly ash transfer pipe 2 and moves downward. After that, the control device 5 transmits a signal to the drive unit 16 to retract the protective case 11, retracts the rod 16B into the cylinder 16A, and moves the collected fly ash receiving unit 12 to the standby position in the guide cylinder 21. The protective case 11 is retracted.

As described above, in this embodiment, the fly ash is collected by the collected fly ash receiving unit 12 at the collection position in the fly ash transfer pipe 2, and the heavy metal concentration is measured. The collected fly ash on the collected fly ash receiving part 12 is blown off and removed by the air injected from. That is, the collection of fly ash, the measurement of heavy metal concentration, and the removal of fly ash are performed at the collection position, that is, under high temperature conditions within the fly ash transfer pipe 2 . Therefore, the collected fly ash will not be taken out of the fly ash transfer pipe and the temperature of the collected fly ash will not drop, so that the collected fly ash will not adhere to the measurement unit 1 and the measurement unit 1 will be prevented from corroding. can. In addition, since the movement of the measurement unit 1 in this embodiment is only the back-and-forth reciprocating movement of the protective case 11 between the standby position and the collection position, the configuration of the drive unit and thus the measurement apparatus as a whole can be simplified. It can be made compact.

Further, based on the temperature signal from the measurement unit 13, the control device 5 appropriately sends a command signal to the cooling air supply unit 14 to supply the cooling air A from the air source into the protective case 11 to cool the air. By sending out the subsequent air B from the air sending part 15, the air in the protective case 11 is replaced and the temperature in the protective case 11 is kept within an appropriate temperature range. As a result, it is possible to avoid damage or failure of the measurement unit 13 due to exposure to inappropriate high temperature conditions.

In addition, the control device 5 receives the measured value of the heavy metal concentration from the measuring unit 13, and based on this measured value, when the measured value is equal to or higher than a specified value, issues a command signal to the pump 8 to drive the pump 8. As a result, the heavy metal elution preventing chemical is supplied from the heavy metal elution preventing chemical storage tank 7 to the kneading device 6 .

The fly ash from the fly ash transfer pipe 2 is carried into the kneading device 6 by the fly ash conveyor 4, and the heavy metal elution preventing agent is sufficiently kneaded with the fly ash to form a kneaded product. This kneaded material is in a state in which elution of heavy metals from the fly ash is prevented. The kneaded material from which elution of heavy metals is prevented in this way is carried out by the kneaded material conveyor 9, stored in the pit 10, and then appropriately disposed of.

In the present embodiment, the measurement of the heavy metal concentration by the measuring device 1 is performed periodically at preset time intervals, but the time interval at which the measurement is performed, in other words, the frequency of measurement, can be set and changed as appropriate. You may do so. For example, measurement frequency setting means (not shown) for setting and changing the measurement frequency of the heavy metal concentration of collected fly ash is provided in the measuring device 1, and the control device 5 drives the driving unit 16 at the set/changed measurement frequency. may be controlled so that heavy metals in the collected fly ash are measured by the measuring device 1 . The measurement frequency may be set or changed by an operator's input, or may be automatically performed according to the waste information obtained in advance.

1 Measuring device (heavy metal concentration measuring device)
2 fly ash transfer conduit 5 control device (medicine amount control means)
7 drug storage tank for preventing heavy metal elution 8 pump 11 protective case (movable support)
12 Collected fly ash receiving part 13 Measuring part 22 Collected fly ash removing part

Claims (7)

It is a heavy metal concentration measuring device that is installed in the fly ash transfer pipe discharged from the incineration facility, collects the fly ash moving in the fly ash transfer pipe, and measures the heavy metal concentration in the collected fly ash. hand,
a collected fly ash receiving part for collecting and receiving the collected fly ash in the fly ash transfer pipe;
a measurement unit that measures the heavy metal concentration of the collected fly ash received by the collected fly ash receiving unit at a position within the fly ash transfer pipe;
a collected fly ash removing unit for removing the collected fly ash received by the collected fly ash receiving unit from the collected fly ash receiving unit.
A heavy metal concentration measuring device characterized by: 2. The fly ash removal unit according to claim 1 , wherein the collected fly ash removal unit is a gas injection body that injects gas to the collected fly ash receiving unit to scatter and remove the collected fly ash from the collected fly ash receiving unit. heavy metal concentration measuring device. The measuring unit and the collected fly ash receiving unit are supported by a movable support, and the movable support moves the collected fly ash receiving unit to one of the fly ash collecting position and the standby position, and collects the fly ash. 2. The heavy metal concentration measuring device according to claim 1, wherein the measuring unit measures the heavy metal concentration of the collected fly ash at the collected fly ash receiving unit at a position. 4. The heavy metal concentration measuring device according to claim 3 , wherein said movable support forms a protective case, in which said measuring section is accommodated, and said collected fly ash receiving section is positioned on its outer surface. 2. The heavy metal concentration measuring apparatus according to claim 1, further comprising measurement frequency setting means for setting a measurement frequency of the heavy metal concentration of the collected fly ash measured by the measuring unit. A fly ash processing apparatus having the heavy metal concentration measuring apparatus according to any one of claims 1 to 5 ,
a heavy metal elution preventing chemical supply means for supplying a heavy metal elution preventing chemical to the fly ash discharged from the fly ash transfer pipe;
a chemical amount control means for controlling the amount of the heavy metal elution preventing chemical supplied from the heavy metal elution preventing chemical supply means based on the concentration of heavy metals contained in the collected fly ash measured by the measuring unit.
A fly ash processing device characterized by: The fly ash discharged from the incineration facility is collected using a heavy metal concentration measuring device installed in the fly ash transfer pipe, and the heavy metal concentration in the collected fly ash is measured. A heavy metal concentration measuring method for measuring,
Positioning the collected fly ash receiving part in the fly ash transfer pipe, receiving the fly ash at the collected fly ash receiving part,
measuring the concentration of heavy metals in the collected fly ash received by the collected fly ash receiving unit by a measuring unit at a position in the fly ash transfer pipe ;
removing the collected fly ash received by the collected fly ash receiving part from the collected fly ash receiving part
A heavy metal concentration measuring method characterized by :

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