JP6935885B2 - How to operate a bug filter in an intermittent operation type waste incinerator - Google Patents

Description

The present invention relates to a method of operating a bag filter in an intermittent operation type waste incinerator, and relates to a technique for suppressing the emission of dioxins even while the incinerator operated intermittently is stopped.

Exhaust gas generated by incineration of municipal waste and industrial waste contains harmful dioxins, and if such harmful substances are discharged into the atmosphere as they are, they will have an adverse effect on the human body.

The Ministry of Health, Labor and Welfare has established guidelines for dioxins contained in the exhaust gas discharged from waste incineration facilities, and by holding the exhaust gas at a high temperature of 850 ° C or higher for 2 seconds or longer, the precursors of dioxins are decomposed and It is required to cool the temperature of the exhaust gas to about 200 ° C. or lower to collect fly ash.

In a general incinerator, the exhaust gas generated from an incinerator is reburned with secondary combustion air at a high temperature to meet the above requirements.

In addition, the dioxin remaining in the exhaust gas after recombustion was adsorbed on the adsorbed substance by putting the adsorbed substance into the cooled exhaust gas and passing it through a filtration type dust collector such as a bag filter. I try to remove it in the state.

By the way, in the above guideline, in carrying out such an operation, a fully continuous combustion type incinerator that operates the incinerator for 24 hours is recommended. In this case, by operating the incinerator all day, it is possible to stably suppress the generation of dioxins. We also recommend a burn-out method that does not leave unburned material in the incinerator when the furnace is shut down.

The adoption of such a full continuous combustion type is possible in urban areas where the processing capacity is large and it is relatively easy to secure workers, but in areas where the amount of waste treated is not large and it is not easy to secure workers. Is difficult to realize. In such areas, incinerators that operate intermittently, such as mechanized batch furnaces that operate for about 8 hours a day and semi-continuous combustion systems that operate for 16 hours, are adopted.

In an incinerator facility that performs such intermittent operation, normal combustion operation is performed during the day, the operation is suspended at night, and the operation is restarted the next morning, so-called DSS (Daily Startup and Shutdown). ) Driving is done.

When such an operation method is adopted, the operation cycle of starting down at night, hibernating at night, starting up the next morning, and performing normal combustion operation during the day is repeated every day. ..

When performing the operation cycle from normal combustion operation to hibernation in a day, especially when the above burn-out method is adopted, the temperature inside the furnace the next morning is about 300 ° C or less, and the bag filter inlet temperature is Since the temperature has dropped to about 130 ° C. or lower, it takes time to raise the temperature of the equipment, which causes problems such as low-temperature corrosion and adhesion of the highly deliquescent chemical reaction product for neutralization to the filter cloth.

In order to deal with this problem, the temperature of the bag filter is lowered by bypassing the bag filter and flowing exhaust gas during the period until the temperature of the bag filter inlet rises to 130 ° C during the start-up operation and after the burnout work. A method is adopted to prevent corrosion and reaction products from sticking to the filter cloth. (Patent Document 1)

Japanese Unexamined Patent Publication No. 6-79118

According to the technique disclosed in Patent Document 1, the exhaust gas is circulated to the low temperature filter provided in the bypass circuit during the period until the bag filter inlet temperature rises to 130 ° C. and after the burnout operation during the start-up operation. As a result, since it does not pass through the bag filter, it is possible to prevent low-temperature corrosion of the bag filter and adhesion of reaction products to the filter cloth, while generating dioxin and harmful substances such as hydrogen chloride and sulfur oxides. There was a problem that it could not be completely removed by the low temperature filter and was released into the atmosphere.

The present invention has been made in view of such problems, and dioxin while preventing low-temperature corrosion of the bag filter and adhesion of reaction products to the filter cloth even during the start-up operation and the start-up operation. The purpose is to provide a waste incinerator that can suppress the emission of harmful substances such as hydrogen chloride and sulfur oxides.

The present invention provides the following solutions.

The invention according to the first feature is waste incinerator provided with a combustion chamber for incinerating an incinerator, a charging device for charging the incinerator into the combustion chamber, and a combustion air supply means for supplying combustion air to the combustion chamber. It has a furnace, a filter cloth arranged in a dust collecting mechanism, and a precoat type bug filter that forms a precoat layer composed of an alkaline agent and an adsorbent on the surface of the filter cloth in advance before performing filtration work, and is discharged from the bag filter. In a waste incinerator equipped with an attracting ventilator that sucks in the exhaust gas and a chimney that is installed downstream of the attracting ventilator and releases the exhaust gas to the atmosphere, combustion operation, start-up operation, hibernation and hibernation are performed throughout the day. It is a bug filter operation method that performs DSS (Daily Start-up and Showdown) operation that performs a start-up operation cycle . The step of removing the deposits adhering to the filter cloth, the step of forming a precoat layer on the surface of the filter cloth after performing the removal operation, and the incinerator from the charging device to the combustion chamber after forming the precoat layer. When the temperature in the combustion chamber falls below a predetermined value, the supply of combustion air is stopped, and the incinerator is stopped to start up the waste incinerator . It has a step of circulating the exhaust gas generated during the start-up operation and the incinerator state to the filter cloth having the precoat layer formed at the start of the start-up operation.

According to the invention according to the first feature, when the incinerator starts down operation, the filter cloth is removed and the precoat layer is formed in response to the command to start the down operation. purifying ability can enter the deactivation operation in the state in which the maximum, during the fall operation, hibernation, and the exhaust gas generated during start-up operation, braze to form a precoat layer during falling operation start Since it is distributed to the cloth, the exhaust gas generated during the down operation, the hibernation state, and the start operation can be reliably cleaned. At the end of the down-down operation, the induction ventilator is also stopped, so in the hibernation state, no power is used, and the entire amount of gas is passed through the bug filter only by drafting the chimney, and the inside of the waste incinerator is negatively affected. Maintain pressure. By doing so, it is possible to avoid the high-temperature and low-temperature damage temperature zones of each device, and to ensure stable operation while ensuring the life of the device even if daily operation and suspension are repeated.

The invention according to the second feature is the invention according to the first feature, and the dust collection mechanism of the bug filter is composed of a plurality of unit dust collection mechanisms, and all the unit dust collection mechanisms are used in the step of performing the withdrawal operation. Provided is a method of operating a bug filter in an intermittent operation type incinerator facility, in which the amount of money is removed substantially at the same time.

According to the invention according to the second feature, it is possible to shorten the start-up operation time and for each unit dust collecting mechanism by performing the withdrawal operation substantially at the same time for all the unit dust collecting mechanisms. Since variations in ventilation resistance can be suppressed and precoat layers having an even thickness can be formed, it is possible to prevent unpurified exhaust gas from being released into the atmosphere in a dormant state.

The invention according to the third feature is the invention according to the first or second feature, in which an ash discharge means is arranged at the bottom as a waste incinerator, and an ash layer, a combustion layer, a carbonized layer, in order from the bottom. Vertical waste having a combustion chamber in which the incinerator is deposited so that a dry layer is formed, and a charging device for storing the incinerator supplied by the waste crane and charging the incinerator from above the combustion chamber. using incinerators, comprising a combustion air supply means for supplying combustion air from below the combustion chamber, falling operation of waste incinerators, combustion from the dosing device after the step of forming a precoat layer on the filter cloth surface stopping the introduction of the incineration of the chamber, to provide a bag filter operation method in the intermittent operation-type incineration facilities with steps of stopping the supply of the combustion air after stopping the introduction of the incinerated.

According to the invention according to the third feature, using a vertical refuse incinerator for combustion air is supplied from below the combustion chamber, to stop the supply of the incinerated after forming the precoat layer on the filter cloth surface, then, by stopping the supply of combustion air, for an object to be incinerated charged into the end of the previous falling operation start can maintain the state of every fire without burning, flue containing bag filter 3 Can be maintained at a high temperature to prevent low temperature corrosion of the bag filter and adhesion of reaction products to the filter cloth.

In addition, even after the start-up operation is completed, high-temperature carbides are retained in the incineration residue, so the exhaust gas generated from the incineration residue circulates in the flue due to the draft of the chimney, but soot and hydrogen chloride contained in the exhaust gas. -Harmful substances such as sulfur oxides can be reliably adsorbed or reaction-removed with a pre-coated bag filter filter cloth at the start of shutdown operation.

According to the present invention, harmful substances such as dioxins, hydrogen chloride, and sulfur oxides are prevented while preventing low-temperature corrosion of the bag filter and adhesion of reaction products to the filter cloth even during the start-up operation and the start-up operation. It is possible to provide a waste incinerator that can suppress the emission of substances.

FIG. 1 is a schematic view showing an incinerator including a vertical waste incinerator according to the present embodiment. FIG. 2 is a flowchart showing a procedure for starting down the vertical waste incinerator according to the present embodiment. FIG. 3 is a flowchart showing a procedure for starting up the vertical waste incinerator according to the present embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. It should be noted that this is only an example, and the technical scope of the present invention is not limited to this.

[Overall configuration of incinerator]
The overall configuration of the incinerator including the vertical waste incinerator according to the present embodiment will be described with reference to FIG.

As shown in FIG. 1, the incinerator of the present embodiment includes a vertical waste incinerator 1, a gas cooling device 2, a bag filter 3, a chemical supply device 4, an attracting ventilator 5, a chimney 6, and the like. It is composed of a primary combustion air supply means 7, a secondary combustion air supply means 8, and a control device 9.

[Structure of vertical waste incinerator 1]
The vertical waste incinerator 1 incinerates irregularly shaped general waste and waste such as industrial waste. An ash discharge means 1a is arranged at the bottom, and an ash layer and a combustion layer are arranged in order from the bottom. A combustion chamber 1b on which incinerated matter is deposited so that a carbonized layer and a dry layer are formed, and a recombustion chamber provided above the combustion chamber 1b and combusting a gas containing unburned components generated in the combustion chamber 1b. 1c, a charging device 1d for charging an object to be incinerated from above the combustion chamber 1b, a combustion chamber temperature detecting means 1e for detecting the temperature in the combustion chamber, and a combustion chamber brightness detection for detecting the brightness in the combustion chamber 1b. The means 1f and the like are provided.

The charging device 1d is composed of a hopper and multiple gates for temporarily storing the incinerated material, and intermittently stores the incinerated material supplied to the loading device 1d by a garbage crane from a garbage pit (not shown). It can be charged into the combustion chamber 1b.

Further, a combustion auxiliary burner (not shown) is provided in the combustion chamber 1b, and the auxiliary fuel is burned at the time of start-up operation when the temperature of the combustion chamber 1b is low, for example, after long-term maintenance. By doing so, the temperature inside the combustion chamber 1b is raised to assist the start-up operation. While the use of such additional fuel can easily raise the temperature in the combustion chamber 1b, it causes a decrease in the efficiency of the entire incinerator, so it is desirable not to use it as much as possible.

The primary combustion air supply means 7 supplies the primary combustion air from below the combustion chamber 1b. The primary combustion air supply means 7 includes a blower, a ventilation passage, an air preheater, and the like (not shown), and supplies the primary combustion air below the combustion chamber 1b, specifically, through the ash discharge means 1a. The primary combustion air passes through the ash layer, the combustion layer, the carbonized layer, and the dry layer in this order to incinerate the incinerator from the drying. The mechanism will be described.

First, the primary combustion air supplied via the ash discharge means 1a receives the heat possessed by the ash layer and is heated, and the high temperature primary combustion air consumes oxygen in the combustion layer to be contained in the incinerated material. Combustibles are burned and become combustion exhaust gas. Since the combustion exhaust gas generated by burning the incinerated material in the combustion layer is a high-temperature inert gas that consumes oxygen, the incinerated material is thermally decomposed in the carbonized layer in an inert atmosphere. The inert thermal decomposition gas generated by the thermal decomposition of the incinerator in the carbonized layer dries the incinerator charged from the charging device 1d in the drying layer. Then, the dry pyrolysis gas is discharged from the dry layer after the incinerated material is dried.

By the above mechanism, the primary combustion air supplied from below the combustion chamber 1b is thermally decomposed and incinerated from the drying of the incinerator.

The secondary combustion air supply means 8 supplies the secondary combustion air to the upper part of the combustion chamber 1b. The secondary combustion air supply means 8 includes a blower, a ventilation path, an air preheater, etc. (not shown), and is discharged from the dry layer by supplying secondary combustion air from an opening (not shown) provided in the upper part of the combustion chamber 1b. Combustion gas components contained in the dry pyrolysis gas are burned.

In the vertical waste incinerator 1 according to the present embodiment, the air ratio of the primary combustion air is about 0.35 to 0.5, and the air ratio of the primary combustion air in the conventional stoker furnace (0.9 to 1). The air ratio is about 1/3 to 1/2 times that of (about 0.0). The air ratio of the secondary combustion air is about 0.7 to 0.8, which is 1.5 compared to the air ratio of the secondary combustion air (about 0.3 to 0.5) in the conventional stoker furnace. The air ratio is about 2.5 times. That is, in the vertical waste incinerator 1 according to the present embodiment, the ratio of the secondary combustion air is larger than the ratio of the primary combustion air.

With such a configuration, the deposited layer of the incinerator is positively pyrolyzed by using the heat of combustion, and the incinerator is dried by using the high-temperature pyrolysis gas generated by the thermal decomposition. Then, the combustible gas component in the gas generated from the deposited layer of the incinerated material is agitated and mixed with the secondary combustion air and burned.

Further, a recombustion chamber 1c is arranged above the combustion chamber 1b of the vertical waste incinerator 1 to reburn combustible gas and harmful components remaining in the combustion gas generated by the supply of secondary combustion air. , 850 ° C. or higher. In this way, the precursor of dioxin production and the unburned gas that causes a foul odor are completely burned in a high temperature atmosphere.

[Structure of gas cooling device 2]
The gas cooling device 2 is capable of supplying the temperature of the exhaust gas discharged from the vertical waste incinerator 1 to the bag filter 3, and is approximately 200 described in the "Guidelines for Prevention of Dioxins Generation Related to Waste Disposal". The temperature is lowered to about ℃ or less, and the type does not matter.

[Configuration of bug filter 3]
The bag filter 3 neutralizes or adsorbs and removes impurities such as dust and harmful components contained in the exhaust gas by filtering the exhaust gas whose temperature has been reduced by the gas cooling device 2. Includes a filter cloth 31 for filtering harmful components.

The bag filter 3 is provided with a plurality of unit dust collecting mechanisms, each unit dust collecting mechanism is provided with a filtration chamber 32 for suspending a plurality of filter cloths 31, and a clean gas chamber 34 equipped with a wiping device 33 is provided above. It is provided. Further, each clean gas chamber 34 is provided with an opening / closing damper (not shown) for switching between the flow and stop of the exhaust gas flow, and the flow and stop of the exhaust gas can be switched for each unit dust collection mechanism. ..

[Structure of drug supply device 4]
A chemical supply device 4 is provided on the upstream side of the bag filter 3, and is contained in an alkaline chemical such as slaked lime for neutralizing acidic components such as hydrogen chloride and sulfur oxide contained in the exhaust gas, and in the exhaust gas. An adsorbent such as activated carbon for adsorbing harmful substances contained in is supplied to the exhaust gas and the bag filter 3.

[Structure of attracting ventilator 5]
The attractive ventilator 5 is a ventilator arranged downstream of the bag filter 3 and is for sucking the exhaust gas purified by the bag filter 3 and releasing the exhaust gas from the chimney 6 to the atmosphere.

[Structure of chimney 6]
The chimney 6 discharges the exhaust gas discharged from the vertical waste incinerator 1 into the atmosphere, and is arranged downstream of the induction ventilator 5.

[Configuration of control device 9]
Depending on the situation, the control device 9 performs a combustion operation for incinerating the incinerated material, a down-down operation for temporarily suspending the incinerator process, and a combustion operation after returning from the temporary suspension. Perform start-up operation to reach.

That is, the incinerator of the present embodiment has a combustion operation in which the incinerated object is incinerated by supplying the primary combustion air and the secondary combustion air into the high temperature combustion chamber 1b, and the primary combustion air and the secondary combustion air. There is a dormant state for a predetermined period in which the supply of the incinerated material is substantially stopped and the incinerated material is not incinerated. Will be done.

The control device 9 in the present embodiment includes a withdrawal device 33, a chemical supply device 4, a primary combustion air supply means 7, a secondary combustion air supply means 8, a incineration product charging device 1d, and a control device 9 according to predetermined conditions. By controlling the induction blower 5, the combustion operation, the start-up operation, the hibernation state, and the start-up operation are repeated to control the intermittent operation.

Further, as will be described later, the control device 9 controls the withdrawal device 33 and the drug supply device 4 to perform the precoating process and the withdrawal operation of the filter cloth 31 of the bag filter 3 at an appropriate timing.

[Precoat processing and withdrawal operation of bug filter 3]
Next, a procedure for forming a precoat layer on the surface of the filter cloth 31 of the bag filter 3 and a procedure for performing a removal operation of a plurality of unit dust collecting mechanisms will be described.

In order to carry out the precoating treatment during the combustion operation of the waste incinerator, the alkaline chemicals and the adsorbent are supplied from the chemical supply device 4 into the bag filter 3 via the flue gas stack according to the command of the control unit 9 for a predetermined time. .. By doing so, a precoat layer of the chemical and the adsorbent having a predetermined thickness is formed on the surface of the filter cloth 31 of the bag filter 3.

Then, when the exhaust gas containing harmful components such as medium dust and sulfur oxides circulates in the bag filter 3, the medium dust mixed in the exhaust gas is filtered on the surface of the precoat layer formed on the surface of the filter cloth 31. And accumulate to form a dust layer. In addition, the acidic harmful gas in the exhaust gas undergoes a neutralization reaction with the chemicals forming the precoat layer to become a neutral gas. In this way, the exhaust gas that has become the clean gas by passing through the filter cloth 31 on which the precoat layer is formed is discharged to the clean gas chamber.

When such filtration is continued, the dust layer deposited on the surface of the precoat layer gradually grows, the ventilation resistance of the exhaust gas is increased, and the load of the induced ventilator 5 is gradually increased.

When the ventilation resistance increases to a certain extent, the following withdrawal processing is performed in order from the first unit dust collecting mechanism to the last unit dust collecting mechanism by the command of the control unit 9.

First, after closing the opening / closing damper (not shown) in the first unit dust collecting mechanism, a pulse jet stream is injected into the filter cloth 31 by the wiping device 33 to deform the filter cloth, thereby accumulating on the surface of the filter cloth 31. The dust layer and the precoat layer are peeled off. At this time, since the opening / closing damper is closed and the exhaust gas from the waste incinerator 1 does not flow in, the peeled medium dust and the like fall downward without being re-scattered.

The dust or the like that has been blown off and dropped downward is collected by a discharge device (not shown) provided at the bottom of the bag filter 3 and discharged to the outside.

Then, by opening the opening / closing damper of the leading unit dust collecting mechanism, the leading unit dust collecting mechanism returns to the initial distribution state. After that, in the same manner, the wiping operation is performed for all the unit dust collecting mechanisms in order, and when the wiping operation of all the unit dust collecting mechanisms is completed, the precoat layer described above is formed.

By doing so, it becomes possible to periodically regenerate the cleaning ability of the filter cloth 31.

The wiping operation and precoating during normal combustion operation may be performed periodically by measuring with a timer (not shown), or the pressure difference before and after the bug filter 3 is measured with a pressure gauge (not shown). It may be set to be carried out when the pressure difference exceeds a predetermined value.

[Start-up operation using vertical waste incinerator 1]
Next, the start-up operation using the vertical waste incinerator 1 during the intermittent operation according to the present embodiment will be described with reference to the flowchart shown in FIG. It should be noted that, during the normal combustion operation, the inside of the combustion chamber 1b is sufficiently heated, and the start-up operation from the state where the combustion assist burner is not in operation will be described in detail.

[Step S100: Withdrawal operation]
First, during the normal combustion operation of the vertical waste incinerator 1, when a command to start the down-down operation is received, the control unit 9 activates the removal device 33 to remove harmful substances and the like adhering to the filter cloth 31. Drop it. (Step S100)

At this time, it is desirable that all the unit dust collecting mechanisms perform the wiping operation substantially at the same time. At the start of the start-up operation, all the unit dust collection mechanisms perform the wiping operation substantially at the same time, so that the time for the down-down operation can be shortened and the variation in the ventilation resistance of each unit dust collection mechanism is suppressed. can do.

If the unit dust collection mechanism is operated in order from the first unit dust collection mechanism at the start of the start-up operation, the ventilation resistance of the unit dust collection mechanism that was operated first becomes smaller, and the exhaust gas flow is concentrated there. It will occur.

That is, after the start-up operation is completed, the induction ventilator 5 is stopped and the opening / closing dampers of all the unit dust collecting mechanisms are opened, so that the exhaust gas in the incinerator gradually flows through the flue by the draft of the chimney 6. If there are variations in the ventilation resistance of the unit dust collection mechanism when it flows into the bag filter 3, the unit dust collection mechanism with low ventilation resistance, that is, the unit with less adhesion of deposits including the precoat layer to the surface of the filter cloth 31. The flow of exhaust gas is concentrated on the dust collection mechanism. Further, even within the same unit dust collection mechanism, there are some places where the ventilation resistance is small, and the exhaust gas flow is concentrated in the places where the deposits including the precoat layer are less adhered.

In this way, even if the precoat layer is formed in the unit dust collection mechanism with variations in the flow of exhaust gas, the thickness of the precoat layer also varies, and as a result, harmful substances and the like cannot be effectively adsorbed and removed. Places occur.

Therefore, in the present embodiment, it is possible to suppress the variation in the thickness of the formed sedimentary layer by performing the wiping operation for all the unit dust collecting mechanisms substantially at the same time.

[Step S110: Formation of precoat layer]
After the wiping off in step S100, the control unit 9 then supplies the alkaline drug and the adsorbent from the drug supply device 4 for a predetermined time in order to form a precoat layer on the surface of the filter cloth 31.

At this time, in step S100, since the wiping operation is performed substantially simultaneously across all the unit dust collecting mechanisms, it is possible to form a precoat layer having a uniform thickness in all the unit dust collecting mechanisms.

When the formation of the precoat layer is completed, the waste incinerator 1 is started down by carrying out the following steps. From the start of the subsequent start-up operation to the completion of the next start-up operation, the exhaust gas generated in the waste incinerator 1 circulates through the filter cloth 31 on which the precoat layer is formed in step S110.

[Step S120: Stopping the input of the incinerator]
When the precoat layer is formed in step S110, the control unit 9 then stops the charging of the incinerator from the charging device 1d (step S120).

[Step S130: Stop supply of primary combustion air]
When the charging of the incinerated material is stopped in step S120, the control unit 9 stops the supply of the primary combustion air from the primary combustion air supply means 7 after a predetermined time has elapsed from the stop of charging the incinerated material (step S130). ).

The amount of primary combustion air supplied during the period from step S120 to step S130 is preferably such that the organic matter in the incinerator deposited below the combustion chamber 1b is sufficiently thermally decomposed and the generated carbide remains firmly. It is preferable to supply as much as possible. That is, the supply of the primary combustion air is stopped at the stage where the incinerated material does not reach combustion and is thermally decomposed.

At this time, if the amount of primary combustion air supplied during the start-up operation is too large, the carbides produced by the thermal decomposition of the organic matter will burn and incinerate, making it difficult to store the carbides as a fire. Become. As a result, the carbides contained in the incinerator residue cannot be used as the pilot fuel when the start-up operation is performed from the hibernation state, and the combustion assist burner must be used.

In this way, by stopping the supply of the primary combustion air after a lapse of a predetermined time from the stop of charging the incinerator into the combustion chamber 1b, the time required for the start-up can be shortened. In addition, the last supplied incinerator can be maintained in a ignited state without being completely burned, and the down-down operation can be performed without using auxiliary fuel. Further, since carbides can be retained in the incinerator residue, the carbides can be used as a pilot fuel in the next start-up operation, and the start-up operation can be carried out without using an auxiliary fuel. At the same time, the start-up operation time can be shortened.

The predetermined time determined in step S130 depends on the amount of incinerator and / or the amount of heat generated from the weight of the incinerator supplied to the loading device 1d by the waste crane immediately before the start of the down-down operation. Set.

That is, since the incinerator supplied from the waste crane to the charging device 1d immediately before the start of the down-down operation is thermally decomposed in the combustion chamber 1b during the down-down operation, the amount and / or the amount of heat generated should be grasped. Then, the amount of primary combustion air required for thermal decomposition can be found. By predetermining the time to supply the primary combustion air for various conditions and determining the time to supply the primary combustion air accordingly, the last charged incinerator can be reliably pyrolyzed. Can be done.

Further, the supply of the primary combustion air may be stopped on condition that the brightness detected by the combustion chamber brightness detecting means 1f is less than a predetermined value.

That is, the brightness of the combustion chamber is detected as indicating the degree of combustion reaction in the combustion chamber 1b. When the brightness in the combustion chamber is greater than the predetermined value, the organic matter in the incinerator is in the process of being thermally decomposed, and entering the hibernation state in this state means that the organic matter remains without being thermally decomposed. Therefore, it is not desirable from the viewpoint of preventing the generation of harmful substances. By stopping the supply of primary combustion air on condition that the brightness in the combustion chamber falls below a predetermined value, the organic matter in the incinerator is sufficiently thermally decomposed, and the generated carbide remains in the hibernation state. It is possible to operate stably.

Further, the supply of the primary combustion air may be stopped when either the condition for the elapse of a predetermined time determined in step S130 or the condition for the brightness to be lower than the predetermined value is satisfied. In this way, by stopping the supply of the primary combustion air when any of the plurality of conditions is satisfied, the time required for the start-up can be shortened, and the organic substances in the incinerator can be reliably removed. It can be thermally decomposed and enter a dormant state with the produced carbides remaining.

[Step S140: Stop supply of secondary combustion air]
Then, when the supply of the primary combustion air is stopped in step S130, the control unit 9 starts the temperature detection in the combustion chamber 1b by the combustion chamber temperature detecting means 1e.

Then, on condition that the temperature in the combustion chamber 1b falls below a predetermined value, the control unit 9 stops the supply of the secondary combustion air from the secondary combustion air supply means 8 (step S140). At the same time, the operation of the induction ventilator 5 is stopped, and the down-down operation is terminated.

When the supply of the primary combustion air is stopped in step S130, the generation of the pyrolysis gas from the incinerated material is substantially stopped, so that the generation of new combustible gas is stopped. On the other hand, it is necessary to supply the secondary combustion air in order to burn the combustible gas generated before the supply of the primary combustion air is stopped and remaining in the combustion chamber. By burning the remaining combustible gas with the secondary combustion air, the temperature of the gas rises temporarily, but as the remaining combustible gas decreases, the temperature inside the combustion chamber 1b gradually decreases. Become.

In the present embodiment, in step S140, the supply of the secondary combustion air is stopped on condition that the temperature in the combustion chamber 1b is lowered to a predetermined temperature (for example, a predetermined temperature between 700 ° C. and 750 ° C.). do. By doing so, the flammable gas generated by the supply of the primary combustion air can be burned to detoxify the malodorous component and the like, and the temperature in the combustion chamber 1b can be maintained at a certain temperature. Moreover, since the supply of air into the combustion chamber 1b is stopped due to the suspension of the supply of the secondary combustion air, it is possible to prevent a subsequent combustion reaction and a decrease in the temperature inside the combustion chamber 1b. You can enter hibernation with. As a result, when the start-up operation is performed from the hibernation state, the start-up operation can be performed by utilizing the amount of heat held in the combustion chamber, which leads to shortening of the start-up time and reduction of the use of auxiliary fuel.

Moreover, since there is carbide stored in the combustion chamber 1b so as to maintain the state of the ignited fire, the carbide can be used as a pilot fuel, and the start-up operation can be performed without using the combustion assist burner. It will be possible to carry out.

At the end of the down-down operation, the induction ventilator 5 is also stopped, so no power is used in the hibernation state, and the entire amount of gas is passed through the bug filter 3 only by the draft of the chimney 6, and the vertical type. Maintain the inside of the waste incinerator 1 at a negative pressure. By doing so, it is possible to avoid the high-temperature and low-temperature damage temperature zones of each device, and to ensure stable operation while ensuring the life of the device even if daily operation and suspension are repeated.

In this way, when the down-down operation of the waste incinerator 1 is started, the filter cloth 31 is wiped off and the precoat layer is formed, so that the down-down operation is started with the purification capacity of the filter cloth 31 maximized. Exhaust gas generated between the start of the start-up operation and the end of the start-up operation is circulated to the filter cloth. Can be reliably cleaned.

In particular, it is possible to shorten the time required for the start-up operation and suppress the variation in the ventilation resistance of each unit dust collection mechanism by performing the removal operation substantially at the same time for all the unit dust collection mechanisms. Since it is possible to form a precoat layer having a uniform thickness, it is possible to prevent unpurified exhaust gas from being released into the atmosphere in a dormant state.

Further, using the vertical waste incinerator 1 in which the primary combustion air is supplied from below the combustion chamber 1b, the supply of the incinerated material is stopped after forming the precoat layer on the surface of the filter cloth 31, and then the primary combustion air is supplied. By stopping the supply, it is possible to maintain the state of the fire without burning the incinerator that was put in last before the start of the shutdown operation, so the flue including the bug filter 3 can be maintained at a high temperature. , It is possible to prevent the low temperature corrosion of the bag filter 3 and the adhesion of the reaction product to the filter cloth. It is desirable that the bug filter 3 is provided with a heat insulating material in order to suppress heat dissipation, and is heated by a heater in order to prevent the acid dew point from falling below the acid dew point.

Even after the start-up operation is completed, the exhaust gas generated from the incinerator residue circulates in the flue due to the draft of the chimney. The filter cloth 31 of the pre-coated bug filter 3 can be reliably adsorbed and removed.

[Start-up operation using vertical waste incinerator 1]
Next, the start-up operation using the vertical waste incinerator 1 according to the present embodiment will be described with reference to the flowchart shown in FIG. As a premise of the start-up operation, it is assumed that the start-up operation is carried out according to the above-mentioned procedure, and the start-up operation is carried out after a pause state for a predetermined time (for example, 8 hours). Such start-up operation is performed at a waste incinerator during intermittent operation.

[Step S200: Start of the induction ventilator]
Upon receiving the start-up operation command, the control unit 9 first activates the induction ventilator 5 (step S200). As a result, the gas staying in the vertical waste incinerator 1 is forcibly discharged from the chimney 6.

[Step S210: Temporary input of incinerator]
Subsequently, the control unit 9 drives the charging device 1d to temporarily charge the incinerated material into the combustion chamber 1b (step S210). At this time, preferably, high-calorie waste that is easily burned is introduced.

Since the incinerator temporarily charged in step S210 is charged to expand the combustion in the combustion chamber 1b in the next and subsequent steps, for example, wood waste, paper waste, waste plastic, etc. It is desirable to put in garbage that is easy to ignite and has a high calorific value.

[Step S220: Start of supply of primary combustion air]
When the incinerated material is put into the combustion chamber 1b in step S210, the control unit 9 activates the primary combustion air supply means and supplies the primary combustion air into the combustion chamber 1b from below (step S220).

At this time, the primary combustion air supplied from below into the combustion chamber 1b first takes away the heat possessed by the ash layer and the carbonized layer of the incinerator deposited in the lower part of the combustion chamber 1b, and is preheated to 150 ° C. or higher. The incinerator charged in step S210 is dried. At the same time, the high-temperature carbide stored in the incinerator residue is ignited as a pilot fuel, and combustion occurs. Once combustion occurs, the combustion region expands due to the action of the supplied primary combustion air and the incinerator introduced in step S210, the temperature inside the combustion chamber 1b gradually rises, and the region of the combustion layer gradually increases. Expanding.

The supply amount of the primary combustion air supplied in step S220 is controlled so as to have a higher air ratio than the primary combustion air during normal operation. That is, by supplying more air than in the normal operation, the pilot fuel is surely ignited and the combustion is controlled to expand.

At this time, the combustion assist burner is not activated, and combustion can be generated and expanded only by the primary combustion air and the pilot fuel. The reason why combustion can be generated without using a combustion assisting burner is that since the vertical waste incinerator 1 is used, the amount of heat possessed by the deposited layer of the incinerated material is transferred to the heating of the layer accumulated above. Because it can be used for. Further, in the above-mentioned start-up operation, by holding the incinerated material in the state of pyrolyzed carbide without burning it, it is possible to store a sufficient amount of heat as a pilot fuel that has been accumulated. Then, the supply of the primary combustion air from below assists the heat transfer upward, and the oxygen in the primary combustion air can cause combustion.

[Step S230: Start of supply of secondary combustion air]
When the primary combustion air is supplied in step S220 and the incinerated object is ignited, the control unit 9 activates the secondary combustion air supply means 8 and starts supplying the secondary combustion air into the combustion branch 1b (step). S230).

In the initial stage of the start-up operation, the temperature in the combustion chamber 1b is lower than that in the normal combustion operation, so that incomplete combustion is likely to occur. Therefore, by supplying the secondary combustion air into the combustion chamber 1b, the combustible gas component generated by the thermal decomposition is burned.

[Step S240: Start of continuous injection of incinerator]
When the supply of the secondary combustion air is started in step S230, the control unit 9 controls the charging device 1d to start continuous charging of the incinerator, and gradually charges the incinerator to burn the incinerator. By expanding and continuing this, the start-up operation is terminated and the normal combustion operation is reached.

As described above, by using the high-temperature carbide remaining in the carbonized layer as the pilot fuel, which is formed by the start-up operation of the vertical waste incinerator 1 according to the present embodiment, the combustion assisting burner is not used. The start-up operation can be completed in a short time.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments described above. In addition, the effects described in the embodiments of the present invention merely list the most preferable effects arising from the present invention, and the effects according to the present invention are limited to those described in the embodiments of the present invention. is not it.

Further, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations.

The waste incinerator of the present invention can be applied to waste incinerators that perform intermittent operation, such as a mechanized batch incinerator and a quasi-continuous combustion incinerator.

1 Vertical waste incinerator 1a Ash discharge means 1b Combustion chamber 1c Recombustion chamber 1d Input device 1e Combustion chamber temperature detection means 2 Gas cooling device 3 Bug filter 31 Filter cloth 32 Filter room 33 Removal device 34 Clean gas room 4 Chemical supply Device 5 Induction blower 6 Chimney 7 Primary combustion air supply means 8 Secondary combustion air supply means 9 Control device

Claims (4)

A combustion chamber for incinerating the incinerated material, a charging device for injecting the incinerated material into the combustion chamber, a waste incinerator equipped with a combustion air supply means for supplying combustion air to the combustion chamber, and a dust collection mechanism. A precoat type bug filter that has an arranged filter cloth and forms a precoat layer composed of an alkaline agent and an adsorbent on the surface of the filter cloth in advance before performing filtration work, and an attraction to suck the exhaust gas discharged from the bag filter. DSS (Daily), which is equipped with a ventilator and a chimney installed downstream of the attracting ventilator and releases exhaust gas to the air, performs a cycle of combustion operation, down-down operation, hibernation and start-up operation in one day. Startup and Combustion) This is a bug filter operation method in an operation type incinerator.
A step of removing deposits adhering to the filter cloth in response to a command to start the down-down operation when performing a down-down operation that shifts from the combustion operation to the hibernation state.
A step of forming a precoat layer on the surface of the filter cloth after performing the wiping operation,
After forming the precoat layer, the charging of the incinerator from the charging device into the combustion chamber is stopped, and when the temperature in the combustion chamber falls below a predetermined value, the supply of combustion air is stopped, and the induced ventilation is stopped. Steps to start down the waste incinerator by stopping the machine,
When falling operation, hibernation, and the exhaust gas generated during start-up operation, the step for circulating the filter cloth forming the precoat layer during the falling operation start,
A method of operating a bag filter in a DSS operation type incinerator facility, which comprises the above. The dust collection mechanism of the bug filter is composed of a plurality of unit dust collection mechanisms, and in the step of performing the removal operation, all the unit dust collection mechanisms are removed substantially at the same time.
The waste incinerator method for performing the DSS operation according to claim 1. As a waste incinerator, an ash discharge means is arranged at the bottom, and it is supplied by a combustion chamber in which incinerators are deposited so that an ash layer, a combustion layer, a carbonized layer, and a dry layer are formed in order from the bottom, and a waste crane. that with vertical refuse incinerator and a dosing device for introducing the incinerated from the upper side of the combustion chamber while storing the object to be incinerated, with the combustion air supply means for supplying combustion air from below the combustion chamber ,
The start-up operation of the waste incinerator is a step of stopping the charging of the incinerated material from the charging device into the combustion chamber after the step of forming the precoat layer on the filter cloth surface.
Comprising the step of stopping the supply of combustion air after stopping the introduction of the incinerated,
The waste incinerator method for performing the DSS operation according to claim 1 or 2. A waste incinerator equipped with a combustion chamber for incinerating the incinerated material, a charging device for charging the incinerated material into the combustion chamber, and a combustion air supply means for supplying combustion air to the combustion chamber.
A precoat type bug filter having a filter cloth arranged in a dust collecting mechanism and forming a precoat layer composed of an alkaline agent and an adsorbent on the surface of the filter cloth in advance before performing filtration work.
A control device that controls DSS (Daily Startup and Shutdown) operation that performs a cycle of combustion operation, start-up operation, hibernation state, and start-up operation in a day.
An attractive ventilator that sucks the exhaust gas discharged from the bag filter,
It is installed downstream of the ventilator and has a chimney that emits exhaust gas to the atmosphere.
When the control device performs a down-down operation that shifts from the combustion operation to the hibernation state, the control device receives a command to start the down-down operation, performs an operation of removing the deposits adhering to the filter cloth, and performs an operation of removing the deposits. Later, a precoat layer is formed on the surface of the filter cloth, and after the precoat layer is formed, the charging of the incinerator from the charging device into the combustion chamber is stopped, and when the temperature in the combustion chamber falls below a predetermined value, combustion is performed. the supply of air is stopped, and performs falling operation of the refuse incinerator by stopping the induced draft fan, when falling operation, hibernation, and the exhaust gas generated during start-up operation, the circulating in the filter cloth during falling operation start the formation of the precoat layer,
A waste incineration facility that operates DSS.

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