JP2019042682A - Exhaust gas treatment method and exhaust gas treatment device - Google Patents

Abstract

To improve removal efficiency of acidic gas contained in exhaust gas as much as possible while suppressing a cost as much as possible, in an exhaust gas treatment method of forming a precoat layer with a chemical for neutralizing exhaust gas onto a filter cloth of a filtration type dust collector 3.SOLUTION: An exhaust gas treatment method includes precoat treatment of forming a precoat layer by using unpulverized sodium bicarbonate as a chemical for neutralizing acidic gas in exhaust gas and monitor treatment for investigating whether practicing the precoat treatment or not during the exhaust gas treatment onto a filtration cloth of a filtration type dust collector 3. Thereby, equipment, for example, for pulverizing sodium bicarbonate is made unnecessary and addition of solidification preventing agent is not required.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a filter cloth of a filter type dust collector for purifying an exhaust gas discharged from a gas generation source such as a waste incinerator, and a precoat layer with a chemical for removing acid gas in the exhaust gas by a neutralizing action. The present invention relates to an exhaust gas processing method for forming an exhaust gas and an exhaust gas processing apparatus.

  The exhaust gas discharged from the waste incinerator contains harmful acid gases such as hydrogen chloride (HCl) and sulfur oxides (SOx) depending on the type of waste to be incinerated.

  Conventionally, after exhaust gas discharged from a waste incinerator is reduced in temperature to 200 ° C. or less by a temperature reducing tower, the exhaust gas is passed through a filtration dust collector to remove dust and acid gas in the exhaust gas. , To be discharged to the atmosphere from the chimney.

  Since the exhaust gas can not be completely removed only by passing it through the filter-type dust collector, many waste incineration plants in Japan currently use the acid gas in the flue from the temperature reducing tower to the filter-type dust collector. In order to neutralize and remove, dry exhaust gas treatment in which slaked lime is blown continuously is adopted.

  For example, Patent Document 1 describes that by adding baking soda powder to the flue upstream of the dust collector, it is made to react with the acid gas in the exhaust gas flowing through the flue and removed.

  In addition, since the removal efficiency of the said acidic gas can not be improved if it is a case where the slaked lime is added as a chemical | medical agent for making an acidic gas react and remove in a flue according to patent document 1, the removal efficiency of the said acidic gas The use of baking soda as the drug is described to enhance The patent document 1 does not describe the average particle size of the baking soda.

  Also, for example, in Patent Document 2, a neutralizing agent in which an anti-caking agent (silica or alumina) is added to baking soda crushed and classified to an average particle diameter of 2 to 100 μm is blown into the flue upstream of the bag filter. It is described.

  As in Patent Document 2, when the sodium bicarbonate is finely pulverized, the surface area (specific surface area = surface area per unit weight) in the total amount of sodium bicarbonate used increases, so it can be said that the removal efficiency of the acid gas is improved. However, in the case of Patent Document 2, the equipment for pulverizing is required, and in the case of the finely pulverized baking soda, since it coagulates and consolidates during storage, it is solidified in the finely pulverized baking soda. The need to add inhibitors also adds to the cost.

  On the other hand, for example, Patent Documents 3 and 4 describe that a precoat layer is formed only with a neutralizing agent (slaked lime) on a filter cloth of a precoat bag filter. It is known that the formation efficiency of the acid gas is higher in the case where the precoat layer is formed as described above, as compared with the case where the neutralizing agent is added to the flue.

  For example, in Patent Document 5, a layer of an exhaust gas treating agent is formed by adding an anti-caking agent (activated carbon) to baking soda (fine powder baking soda) pulverized to an average particle diameter of 5 to 20 μm on the filter cloth surface of a bag filter. It is described. In paragraph 0014 of this patent document 5, it is described that “sintered activated carbon as an anti-caking agent is mixed with baking soda since baking soda coagulates and solidifies as soon as it is pulverized to a fine powder. There is.

Unexamined-Japanese-Patent No. 2004-321958 Japanese Patent Application Publication No. 2007-21442 Patent No. 2520558 Patent No. 2558048 Patent No. 4401639

  In the case of Patent Document 5 described above, it can be said that the removal efficiency of acid gas is higher than that of Patent Document 1-4 above, but from the relationship using finely powdered sodium bicarbonate, equipment for finely pulverizing sodium bicarbonate is required, and Since it is necessary to add anti-caking agent (activated carbon) to baking soda, there is a problem that cost increases.

  In view of such circumstances, the present invention provides an exhaust gas treatment method and an exhaust gas treatment apparatus for forming a precoat layer with a chemical for neutralizing exhaust gas in a filter cloth of a filtration type dust collector as much as possible. It is an object of the present invention to increase the removal efficiency of the acid gas contained in the exhaust gas as much as possible while suppressing.

  The present invention is an exhaust gas treatment method in which an exhaust gas discharged from a gas generation source is passed through a filtration type dust collector, and for filtering acid gas in the exhaust gas into a filter cloth of the filtration type dust collector. It is characterized in that a precoating process of forming a precoating layer using uncrushed baking soda as a medicine and a monitoring process of checking whether or not the precoating process is to be performed during exhaust gas treatment are performed.

  Here, the uncrushed baking soda refers to a powder in a state of being manufactured chemically. For example, in the case of uncrushed baking soda which is in a state of being chemically produced from a salt which is a raw material by the Solvay method, the average particle diameter is about 150 μm. In addition to the above, for example, in the non-patent document (M. Kuniyoshi, “Tosoh Research and Technology Report, Volume 40 (2004), pages 31 to 35”), “average of sodium hydrogencarbonate (sodium bicarbonate) The particle size is 45-400 [mu] m and is said to be produced by the bicarbonation of aqueous sodium hydroxide solution. From this description, it can be said that the uncrushed baking soda includes those having an average particle diameter in the range of 45 to 400 μm.

  In this configuration, since the agent is uncrushed baking soda, equipment for pulverization becomes unnecessary as compared with the case of pulverizing baking soda as in Patent Document 5, for example, and an anti-caking agent is added. The cost is greatly reduced, such as eliminating the need.

  Then, in a state where the uncrushed baking soda is formed on the filter cloth as a precoat layer, when the exhaust gas passes through the filter cloth, the acid gas in the exhaust gas is efficiently neutralized by the precoat layer and removed. It will be done.

  By the way, in the above exhaust gas treatment method, the monitoring process includes a measurement process for measuring the concentration of acid gas contained in the exhaust gas on the outlet side of the filtration type dust collector during the exhaust gas treatment, and the filtration during the exhaust gas treatment. Detection processing for detecting a differential pressure between the inlet side and the outlet side of the dust collector, a first determination processing for determining whether or not the measurement result by the measurement processing is equal to or more than a predetermined threshold, and the detection processing And performing a second determination process of determining whether or not the detection result is equal to or greater than a predetermined threshold value, and performing an affirmative determination in any one of the first determination process and the second determination process, the precoat process Can be configured to

  In this configuration, it is possible to perform the precoat treatment at a time when the effect of the precoat layer is reduced, that is, at an appropriate timing. As a result, the effect of removing the acid gas in the exhaust gas is improved, and waste of the chemical (uncrushed baking soda) can be suppressed as compared with the case where the precoating treatment is periodically performed.

  Further, in the exhaust gas treatment method, the precoating treatment can be configured to blow in a predetermined amount of uncrushed baking soda of a supply amount set in advance into the filtration type dust collector within a predetermined time.

  In this configuration, for example, supply of a chemical (uncrushed baking soda) for forming a precoat layer, as compared with the case of continuously adding finely ground sodium bicarbonate into a flue without using it as a precoat layer as in Patent Document 2, for example. Since it is possible to minimize the amount necessary, it can contribute to the reduction of running costs.

  Furthermore, in the above exhaust gas treatment method, when the uncrushed baking soda is blown, the flow rate (filtration speed) of the exhaust gas to be passed through the filtration type dust collector is greater than the filtration speed when blowing slaked lime or finely crushed sodium bicarbonate. It can be configured to be large.

  Here, generally, the slaked lime has an average particle diameter of 10 to 20 μm. Further, generally, the finely ground baking soda refers to, for example, those pulverized to a fine particle size of, for example, 5 to 20 μm from an uncrushed state.

  That is, although the uncrushed baking soda has a larger average particle diameter than the finely ground baking soda, according to the configuration, the uncrushed baking soda is surely adhered to the filter cloth of the filtration type dust collector in the precoating treatment. It will be possible to

  Further, the present invention is an exhaust gas treatment apparatus for passing exhaust gas discharged from a gas generation source to a filtration type dust collector, wherein acid gas in the exhaust gas is neutralized by a filter cloth of the filtration type dust collector. It is characterized in that it comprises a precoating means for forming a precoat layer using uncrushed baking soda as a chemical for the purpose, and a monitoring means for checking whether or not the precoating means is to be carried out during exhaust gas treatment.

  In this configuration, since the agent is uncrushed baking soda, equipment for pulverization becomes unnecessary as compared with the case of pulverizing baking soda as in Patent Document 5, for example, and an anti-caking agent is added. The cost is greatly reduced, such as eliminating the need.

  Then, in a state where the uncrushed baking soda is formed on the filter cloth as a precoat layer, when the exhaust gas passes through the filter cloth, the acid gas in the exhaust gas is efficiently neutralized by the precoat layer and removed. It will be done.

  By the way, in the above exhaust gas processing apparatus, the monitoring means measures the concentration of acid gas contained in the exhaust gas at the outlet side of the filtration type dust collector during the exhaust gas processing, and the exhaust gas processing. A detection means for detecting a differential pressure between the inlet side and the outlet side of the filtration type dust collector, a first determination means for determining whether or not the measurement result by the measurement means is equal to or more than a predetermined threshold, and the detection means And second determining means for determining whether or not the detection result by the second determination means exceeds a predetermined threshold value, and when the positive determination is made by any one of the first determining means and the second determining means, the precoat means It can be configured to run.

  In this configuration, it is possible to perform the precoat treatment at a time when the effect of the precoat layer is reduced, that is, at an appropriate timing. As a result, the effect of removing the acid gas in the exhaust gas is improved, and waste of the chemical (uncrushed baking soda) can be suppressed as compared with the case where the precoating treatment is periodically performed.

  Further, in the exhaust gas treatment apparatus, the precoating means may be configured to blow in a predetermined amount of uncrushed baking soda in a predetermined supply amount in a predetermined time within a predetermined time.

  In this configuration, for example, supply of a chemical (uncrushed baking soda) for forming a precoat layer, as compared with the case of continuously adding finely ground sodium bicarbonate into a flue without using it as a precoat layer as in Patent Document 2, for example. Since it is possible to minimize the amount necessary, it can contribute to the reduction of running costs.

  In the above-mentioned exhaust gas treatment apparatus, when the uncrushed baking soda is blown, the flow rate (filtration speed) of the exhaust gas passing through the filtration type dust collector is greater than the filtration speed when blowing slaked lime or finely crushed sodium bicarbonate It can be configured to be large.

  Here, generally, the slaked lime has an average particle diameter of 10 to 20 μm. Also, generally, the finely ground baking soda refers to, for example, those pulverized to a fine particle size, for example, an average particle diameter of 5 to 20 μm from an uncrushed state.

  That is, although the uncrushed baking soda has a larger average particle diameter than the finely ground baking soda, according to the configuration, the uncrushed baking soda is surely adhered to the filter cloth of the filtration type dust collector in the precoating treatment. It will be possible to

  ADVANTAGE OF THE INVENTION According to the exhaust gas processing method and exhaust gas processing apparatus which concern on this invention, it becomes possible to raise as much as possible the removal efficiency of the acidic gas contained in waste gas, suppressing cost as much as possible.

It is a figure showing typically the composition of one embodiment of the refuse incinerator waste gas processing device concerning the present invention. It is a figure which shows the flowchart for demonstrating the waste gas processing method using the incinerator waste gas processing apparatus of FIG.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the attached drawings.

  1 and 2 show an embodiment of the present invention. The waste incinerator exhaust gas processing device of the illustrated example includes the waste incinerator 1, the cooling device 2, the filter type dust collector 3, the induction ventilator 4, the chimney 5, the medicine supply device 6, the discharge device 7, the exhaust gas circulation fan 8, The control unit 10 includes first, second, third and fourth sensors 11, 12, 13, 14 and the like.

  The waste incinerator 1, for example, burns waste such as industrial waste (not shown) and infectious medical waste put in a predetermined package, and the type of the incinerator is not limited.

  Although the cooling device 2 is not shown in detail, the boiler that cools the high temperature exhaust gas discharged from the waste incinerator 1 to, for example, about 220 ° C., and the exhaust gas cooled by the cooling device 2 are further reduced to about 200 ° C. or less It has a temperature reducing tower that reduces the temperature.

  The filtration type dust collecting apparatus 3 neutralizes and filters soot and harmful gas components in the exhaust gas reduced by the cooling device 2 and is called a bag filter.

  The induction ventilator 4 sucks the exhaust gas in the filtration type dust collector 3 and discharges it from the chimney 5 to the atmosphere.

  The medicine supply device 6 collectively blows the medicine for a predetermined filtration time into the filtration type dust collection device 3, and includes a medicine storage tank 61, a blower 62, an unloading device 63, and the like.

  The drug storage tank 61 stores a drug for neutralizing the acid gas in the exhaust gas. As the drug, uncrushed baking soda is used. The uncrushed baking soda, as mentioned above, refers to the powder in the state of being produced chemically.

  The blower 62 generates carrier air for blowing the medicine in the medicine storage tank 61 into the inlet side of the filtration type dust collecting apparatus 3. The carry-out device 63 cuts out the medicine from the medicine outlet of the medicine storage tank 61.

  The discharge device 7 is for cleaning a filter cloth (not shown) in the filtration type dust collection device 3, and includes a compressed air supply source 71, a valve 72, and the like.

  The compressed air supply source 71 generates compressed air used to clean the filter cloth in the filtration type dust collector 3. The valve 72 controls the amount by which the compressed air generated by the compressed air supply source 71 can be supplied to the filter-type dust collector 3.

  The exhaust gas circulation fan 8 adjusts the amount of exhaust gas so that the flow velocity (filtration speed) of the exhaust gas passing through the filtration type dust collecting device 3 becomes a predetermined value (1.2 m / min or more) when performing the pre-coating process. .

  The control unit 10 will be described in detail later, but if the acid gas concentration at the outlet of the filtration type dust collector 3 rises and exceeds the threshold value X or the like, it becomes necessary to perform the precoating process. After the removal process for cleaning the filter cloth in the device 3 is performed, the precoat process for forming a precoat layer with a chemical for neutralizing the acid gas in the filter cloth in the filtration type dust collector 3 is performed.

  The first sensor 11 continuously measures the concentration of the acid gas contained in the exhaust gas at the outlet side of the filtration type dust collector 3. The first sensor 11 is, for example, a known laser analyzer.

  The second sensor 12 measures the pressure on the inlet side of the filtration type dust collector 3 continuously.

  The third sensor 13 measures the pressure on the outlet side of the filtration type dust collector 3 continuously.

  The fourth sensor 14 measures the amount of exhaust gas on the outlet side of the filtration type dust collector 3 continuously.

  Next, with reference to FIG. 2, an exhaust gas treatment method using the exhaust gas treatment apparatus according to this embodiment will be described.

  During the operation operation of the waste incineration, the exhaust gas discharged from the waste incinerator 1 is subjected to an exhaust gas treatment to be purified by passing it through the filter type dust collector 3.

  During the exhaust gas processing, the first and second determination processing (monitoring processing) shown in steps S1 and S2 are performed, and when a positive determination is made in any one determination processing, the filtration device 7 is filtered by the payout device 7 in step S3. A removal process of cleaning the filter cloth of the dust collection device 3 is performed.

  The first determination processing measures the concentration of the acid gas contained in the exhaust gas on the outlet side of the filtration dust collector 3 based on the output from the first sensor 11, and the measurement result becomes equal to or higher than a predetermined threshold X It is determined whether or not it is.

  The second determination process calculates a differential pressure between the inlet side and the outlet side of the filtration type dust collector 3 based on the outputs from the second and third sensors 12 and 13, and the calculation result is a predetermined threshold Y It is determined whether or not it is more than.

  In this embodiment, first, the second determination process is performed when the negative determination is made in the first determination process, and the process returns to the first determination process when the negative determination is made in the second determination process. However, it is also possible to perform the first and second determination processes simultaneously in parallel.

  Then, the control unit 10 performs the payout process, for example, by operating the compressed air supply source 71 and the valve 72.

  Specifically, in the pay-off process, for example, the valve 72 is opened and closed at a predetermined timing and the compressed air supply source 71 is operated for a predetermined time to jet jet the compressed air into the filtration type dust collector 3 as a pulse. Then, the deposit on the surface of the filter cloth in the filtration type dust collector 3 is removed.

  After the payout process is performed, the process proceeds to the precoat process shown in the following steps S4 to S5.

  That is, in steps S4 and S5, drugs corresponding to the preset concentration and precoat interval are collectively blown into the filtration type dust collector 3 by the drug supply device 6.

  The injection of the medicine is performed, for example, by operating the blower 62 and the unloading device 63 for a predetermined time (a few minutes to a few minutes) for example.

  The flow rate (filtration rate) of the exhaust gas passing through the filtration type dust collector 3 when blowing in the uncrushed baking soda is generally slaked lime (eg, average particle diameter 10 to 20 μm) or finely ground sodium bicarbonate (eg, average particle diameter (5 to 20 μm) is set to be higher than the filtration rate when blowing in.

  By the way, in general, in the case of performing a precoating process such as blowing in the slaked lime or the finely pulverized sodium bicarbonate, the flow rate of the exhaust gas (filtration speed) is set to 0.8 to 1.0 m / min. On the other hand, the exhaust gas flow rate (filtration speed) in the case of performing the pre-coating process such as blowing the uncrushed baking soda in this embodiment is, for example, 1.0 to 1.5 m / min, preferably 1.2 m / min. It is set above. The exhaust gas flow rate can be adjusted by the amount of circulating exhaust gas from the exhaust gas circulation fan 8.

  Thus, if the flow rate (filtration rate) of the exhaust gas is specified, the uncrushed sodium bicarbonate has a larger average particle diameter than the slaked lime or the finely crushed sodium bicarbonate, but the uncrushed sodium bicarbonate is filtered in the precoating process. It becomes possible to make the filter cloth of the dust collector 3 adhere reliably.

  Further, when the medicine is cut out from the medicine discharge port of the medicine storage tank 61 by the carry-out device 63, since the medicine is uncrushed baking soda, it does not adhere to the medicine storage tank 61 or the carry-out apparatus 63 and clogged. Therefore, there is no need to add an anti-caking agent.

  When such a supply process is completed, that is, when an affirmative determination is made in step S7, the process returns to step S1.

  Here, the correspondence between the items described in this embodiment and the items described in the claims will be described. Step S1 corresponds to "first determination means" described in the claims, step S2 corresponds to "second determination means" described in the claims, and steps S1 and S2 correspond to claims. In the "monitoring means" described above, the steps S4 and S5 respectively correspond to the "pre-coating means" described in the claims.

  Further, processing (not shown) of recognizing the measurement result based on the output from the first sensor 11 by the first sensor 11 and the control device 10 corresponds to the “measurement means” described in the claims. A process (not shown) of recognizing the detection result based on the outputs from the second and third sensors 12 and 13 by the third sensors 12 and 13 and the control device 10 corresponds to the “detection means” described in the claims, Each corresponds.

  As described above, according to the embodiment to which the present invention is applied, when forming the precoat layer on the filter cloth of the filtration type dust collecting apparatus 3, it is preferable to use uncrushed baking soda as the agent for forming the precoat layer. I have to.

  This eliminates the need for equipment for pulverizing sodium bicarbonate as compared with pulverizing sodium bicarbonate as in Patent Document 5, for example, and eliminates the need to add an anti-caking agent, thereby significantly reducing costs. .

  And, in a state where the uncrushed baking soda is formed as a precoat layer on the filter cloth of the filtration type dust collector 3, when the exhaust gas passes through the filter cloth, the acid gas in the exhaust gas is efficiently used by the precoat layer. It will be neutralized and removed.

  Further, in the above embodiment, since the precoat treatment is performed at a time when the effect of the precoat layer is reduced, that is, at an appropriate timing, the effect of removing the acid gas in the exhaust gas is improved, and the precoat treatment is periodically performed. It is possible to suppress the wasteful use of the medicine (uncrushed baking soda) compared to the case where it is carried out.

  Furthermore, in the above embodiment, the agent for forming the precoat layer (uncrushed sodium bicarbonate as compared with the case where, for example, as in Patent Document 2 finely pulverized sodium bicarbonate is continuously added to the flue without using the precoat layer, Since it is possible to minimize the supply amount of), it can contribute to the reduction of running costs.

  In addition, this invention is not limited only to the said embodiment, It is possible to change suitably within the range of a claim, and the range equivalent to the said range.

  The present invention is directed to a filter cloth of the filtration type dust collector by blowing in a chemical for neutralizing acid gas in the exhaust gas in a filtration type dust collector which purifies exhaust gas discharged from a waste incinerator. It is possible to use suitably for the waste incinerator waste gas processing method which forms a precoat layer, and a waste incinerator waste gas processing device.

1 Garbage incinerator
2 Cooling system
3 Filter-type dust collector
4 Induction ventilator
5 chimneys
6 Drug supply device
61 Drug storage tank
62 Blower
63 Unloading device
7 Payout device
71 Compressed air supply source
72 valve
8 exhaust gas circulation blower 10 control unit 11 first sensor 12 second sensor 13 third sensor 14 fourth sensor

The present invention is an exhaust gas treatment method in which an exhaust gas discharged from a gas generation source is passed through a filtration type dust collector, and for filtering acid gas in the exhaust gas into a filter cloth of the filtration type dust collector. Precoat treatment for forming a precoat layer using uncrushed baking soda as a medicine, pay-off treatment for cleaning the filter cloth, and monitoring treatment for examining whether or not the precoat treatment is to be performed during exhaust gas treatment The monitoring process measures the concentration of acid gas contained in the exhaust gas on the outlet side of the filtration dust collector during exhaust gas treatment, and whether the measurement result is equal to or higher than a predetermined threshold value X The first determination process of determining the differential pressure between the inlet side and the outlet side of the filtration type dust collector during exhaust gas processing is calculated, and it is determined whether the calculation result is equal to or greater than a predetermined threshold Y While performing the second determination process, When it is determined in the first determination process that the threshold value X has been reached or more, or when it is determined in the second determination process that the threshold value Y has been exceeded, the pre-coating process is performed after the payment process is performed. The precoat treatment is performed by using a flow rate (filtration speed) of the exhaust gas which is allowed to pass through the filtration type dust collector when blowing in a predetermined amount of uncrushed baking soda, while blowing in slaked lime or finely ground sodium bicarbonate The uncrushed sodium bicarbonate is collectively blown into the filtration type dust collection device within a predetermined time by setting the flow rate (filtration speed) of the exhaust gas to be passed through the dust collection device higher than that of the exhaust gas .

Further, the present invention is an exhaust gas treatment apparatus for passing exhaust gas discharged from a gas generation source to a filtration type dust collector, wherein acid gas in the exhaust gas is neutralized by a filter cloth of the filtration type dust collector. Precoat means for forming a precoat layer using uncrushed baking soda as a chemical agent, a discharge means for cleaning the filter cloth, and a monitoring means for checking whether the precoat means is to be executed during exhaust gas treatment , have a, the monitoring means, the concentration of the acidic gases contained in the outlet side of exhaust gas of the filter-type dust collector in an exhaust gas treatment were measured, whether the measurement result exceeds a predetermined threshold value X The differential pressure between the inlet side and the outlet side of the filtration type dust collector is calculated during exhaust gas processing, and it is determined whether or not the calculation result is equal to or greater than a predetermined threshold Y. A second determination unit, and the first determination unit When it is determined that the threshold value X has been exceeded or the second determination means has determined that the threshold value Y has been exceeded, the pre-coating means is executed after the payment means has been executed. The pre-coating unit is configured to collect the flow rate (filtration speed) of the exhaust gas passing through the filtration type dust collector when blowing in a predetermined amount of uncrushed baking soda, while blowing in slaked lime or finely crushed sodium bicarbonate. The uncrushed baking soda is collectively blown into the filtration type dust collection device within a predetermined time by setting the flow rate (filtration speed) of the exhaust gas to be passed through the dust device to be larger .

During this exhaust gas treatment, the first and second determination processing (monitoring processing) shown in steps S1 and S2 are performed, and when it is determined in the first determination processing that the threshold value X or more is reached, or in the second determination processing When it is determined that the threshold value Y is reached or more , in step S3, a payout process of cleaning the filter cloth of the filtration type dust collector 3 by the payout device 7 is performed.

In this embodiment, first, the second determination process is performed when it is determined that the threshold value X is not exceeded in the first determination process, and when it is determined that the threshold value Y is not exceeded in the second determination process. It is configured to return to the first determination process. However, it is also possible to perform the first and second determination processes simultaneously in parallel.

When such supply process is finished, i.e. when an affirmative determination is made in step S 5, the process returns to step S1.

Here, the correspondence between the items described in this embodiment and the items described in the claims will be described. Step S1 corresponds to “first determination process, first determination means” in the claims, and step S2 corresponds to “second determination process, second determination means” in the claims. Steps S1 and S2 refer to the "monitoring process, monitoring means" described in the claims, and step S3 refers to the "payment process, the payment means" described in the claims, and steps S4 and S5 refer to the patents. These correspond to “pre-coat treatment, pre-coat means” described in the claims.

Claims (8)

An exhaust gas treatment method comprising passing exhaust gas discharged from a gas generation source through a filtration type dust collector,
A precoat process of forming a precoat layer using uncrushed baking soda as a chemical for neutralizing acid gas in the exhaust gas, on the filter cloth of the filtration type dust collector;
The exhaust gas processing method characterized by performing monitoring processing which checks whether said precoat processing is performed during exhaust gas processing. In the exhaust gas treatment method according to claim 1,
The monitoring process is
Measurement processing for measuring the concentration of acid gas contained in the exhaust gas on the outlet side of the filtration type dust collector during exhaust gas processing;
A detection process for detecting a pressure difference between an inlet side and an outlet side of the filtration type dust collector during exhaust gas treatment;
A first determination process of determining whether a measurement result by the measurement process is equal to or more than a predetermined threshold value;
Performing a second determination process of determining whether the detection result by the detection process is equal to or more than a predetermined threshold value;
The pre-coat process is performed when a positive determination is made in any one of the first determination process and the second determination process. In the exhaust gas treatment method according to claim 2,
In the pre-coat process, an uncrushed baking soda of a supply amount set in advance is collectively blown into the filtration type dust collector within a predetermined time, and the exhaust gas treatment method. In the exhaust gas treatment method according to claim 3,
When blowing in the uncrushed baking soda, the flow rate (filtration speed) of the exhaust gas to be passed through the filtration type dust collector is set to be higher than the filtration speed when blowing in slaked lime or finely ground baking soda. Exhaust gas treatment method. An exhaust gas treatment apparatus for passing exhaust gas discharged from a gas generation source to a filtration type dust collector,
Precoat means for forming a precoat layer using uncrushed baking soda as a chemical for neutralizing acid gas in the exhaust gas in the filter cloth of the filtration type dust collector;
And a monitoring means for checking whether or not the precoating means is to be executed during the exhaust gas treatment. In the exhaust gas treatment device according to claim 5,
The monitoring means
Measuring means for measuring the concentration of acid gas contained in the exhaust gas at the outlet side of the filtration type dust collector during exhaust gas treatment;
Detection means for detecting a pressure difference between the inlet side and the outlet side of the filtration type dust collector during exhaust gas treatment;
A first determination unit that determines whether the measurement result by the measurement unit is equal to or more than a predetermined threshold value;
And second determining means for determining whether or not the detection result by the detecting means is equal to or greater than a predetermined threshold.
An exhaust gas processing apparatus, characterized in that the precoat means is executed when an affirmative determination is made by any one of the first determination means and the second determination means. In the exhaust gas processing device according to claim 6,
The exhaust gas treatment apparatus according to claim 1, wherein the precoating means blows in a predetermined amount of uncrushed baking soda of a supply amount set in advance into the filtration type dust collector within a predetermined time. In the exhaust gas processing device according to claim 7,
When blowing in the uncrushed baking soda, the flow rate (filtration speed) of the exhaust gas to be passed through the filtration type dust collector is set to be higher than the filtration speed when blowing in slaked lime or finely ground baking soda. Exhaust gas treatment equipment.

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