JP4071883B2 - Waste incinerator and waste incineration method - Google Patents

Description

次に、図３に基づいて本発明の第二実施形態に係るごみ焼却装置を示す（請求項１に対応する）。
本実施形態は、ガス冷却室６Ａを燃焼炉１から切り離したごみ焼却装置に適用した例である。ここで、ガス冷却室６Ａでは、排ガスが下向流となって流れるようになっている。
【００３１】
ガス冷却室６Ａは、ダクト１８ａを介して燃焼室２に連絡している。ガス冷却室６Ａは、ダクト１８ｂを介して空気予備加熱器７に連絡している。
また、本実施形態では、空気予熱器８とバグフィルタ４との間に減温塔３２が設けられている。空気予熱器８と減温塔３２とはダクト２０ａで連絡し、減温塔３２とバグフィルタ４とはダクト２０ｂを介して連絡している。
【００３２】
さらに、本実施形態では、３個の切替弁２４，２５，２７で切替制御されるようになっている。
なお、その他の構成は、図１に示す第一実施形態と同様であるから、同一機器、部材には同一符号を付して説明を省略する。
本実施形態においても、第一実施形態と同様の作用効果を奏することが可能である。
【００３３】
なお、本発明に係るごみ焼却炉について図１、図３に示す実施形態によって説明したが、本発明はこれらに限定されることなく、バグフィルタを備えたごみ焼却炉であれば、如何なる形式のものにも適用できることはいうまでもない。
また、本発明は、ボイラを備えた設備にあっても同様の使用により同様の効果が期待できる。つまり、ボイラ以降の所定の位置に早期通ガス用バーナ１７を設け、立ち上げは、ボイラ加熱設備（バーナ）と併用することができる。
【００３４】
さらに、図１、図３に示す実施形態では、早期通ガス用バーナ１７をガス冷却室６，６Ａのガス冷却ノズル９の下流側に設けた場合について説明したが、本発明はこれらに限定されることなく、バグフィルタ４の上流側に位置する中間設備３内であれば、何処に設けても良い。
【００３５】
【発明の効果】
以上のように、請求項１または請求項２に係る発明によれば、焼却炉の休止時の中間設備内の温度を１３０℃以上に保持するので、立ち上げと同時に排ガスをバグフィルタに通ガスさせることが可能となる。
【図面の簡単な説明】
【図１】本発明の第一実施形態に係るごみ焼却装置を示す図である。
【図２】第一実施形態における制御装置のフローチャートである。
【図３】本発明の第二実施形態に係るごみ焼却装置を示す図である。
【符号の説明】
１ 焼却炉
２ 燃焼室
３ 中間設備
４ バグフィルタ
５ 誘引送風機
６，６Ａ ガス冷却室
７，８ 空気予熱器（熱交換器）
９ ガス冷却ノズル
１０ 煙突
１７ 早期通ガス用バーナ
２８ 温度センサ
２９ 温度制御装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waste incinerator and a waste incineration method.
[0002]
[Prior art]
When the incinerator is cold-started, generally, the furnace body is heated by a burner. In this case, the time required for the exhaust gas temperature at the bag filter to reach 130 ° C. or higher due to heat absorption by the equipment installed between the incinerator and the exhaust gas treatment equipment (bag filter) takes 2-3 hours. The exhaust gas was discharged from the chimney without being treated with dust. Naturally, the dioxins contained in the dust are also discharged out of the system together with the exhaust gas, which has been the cause of the high concentration of dioxins being discharged at startup.
[0003]
Therefore, I would like to pass the bag filter through early, but if exhaust gas with a low temperature is passed through the bag filter, the decontamination of dust on the bag filter surface (mainly caused by calcium chloride) will occur. After the exhaust gas temperature rises to 130 ° C or higher, the bypass route is switched to the gas passage route.
As a countermeasure, there is a method (Japanese Patent Laid-Open No. 10-122548) that bypasses the intermediate equipment and quickly raises the temperature of the exhaust gas at the bag filter inlet.
[0004]
[Problems to be solved by the invention]
However, with this method of bypassing the intermediate equipment and increasing the exhaust temperature of the bag filter inlet quickly, the temperature drop at the time of switching and the temperature rise time can be shortened. It is not.
On the other hand, in an incinerator using a bag filter, generally, the heater in the bag filter is kept warm when the furnace is stopped.
[0005]
However, in this method, when the exhaust gas temperature is passed at 130 ° C. or lower, the temperature in the bag filter is rapidly cooled, the water vapor in the exhaust gas is condensed, and the bag filter surface has a hygroscopic dust (chloride). Calcium etc.) absorbs water and causes deliquescence.
In order to prevent clogging of the bag cloth of the furnace cloth, a method of providing a heater at the bag filter inlet and raising the temperature (Japanese Patent Publication No. 55-40287, Japanese Patent Publication No. 56-87420, Japanese Patent Publication No. 58-14923) is known. It has been.
[0006]
However, each of these methods is a method of raising the temperature of the bag filter inlet, and regarding the exhaust gas that is cooled while passing through the intermediate facility installed between the bag filter from the furnace at the time of startup. Not considered.
[0007]
In addition, in Japanese Patent Publication No. 1-169, the details of how to use the heater device corresponding to startup and shutdown are specified, but the idea is that the heater is used to assist the cooling by the intermediate equipment. There is no mention of dioxin reduction at startup.
In the invention according to Japanese Patent Publication No. 1-169, it is necessary to have an ability to raise the temperature of the exhaust gas at about 20 ° C. after passing through the intermediate equipment to 130 ° C. at the bag filter inlet at the time of startup.
[0008]
Furthermore, in the invention according to Japanese Patent Publication No. 1-169, exhaust gas always passes through the heater even in a stationary state where the heater is not used, and thus there are problems of dust adhesion, pressure loss, and corrosion.
Further, in the invention according to Japanese Patent Application Laid-Open No. 9-310832, garbage is introduced after the bag filter inlet temperature is raised to a predetermined temperature at the time of startup by a burner installed in the furnace, and then the bag is sealed after the dust sealing is completed. A filter gas passing means is used.
[0009]
In this case, in the cold start, the burner temperature rise is absorbed by the refractory to the furnace body, recombustion chamber, and gas cooling chamber cooling nozzle, and it takes several hours for the bag filter inlet temperature to reach the predetermined temperature. End up.
Further, the invention according to Japanese Patent Application Laid-Open No. 9-310832 is suitable for facilities equipped with a boiler, but is not rational for an intermittent operation furnace without a boiler.
[0010]
The present invention has been made to solve such conventional problems, and an object of the present invention is to provide a waste incinerator and a waste incinerator capable of passing gas through a bag filter at the same time as waste is introduced into an incinerator and exhaust gas is generated. It is to provide a method.
[0011]
[Means for Solving the Problems]
The invention according to claim 1 includes an incinerator, an intermediate facility, a bag filter, and a chimney, and has a small amount of refractory after the cooling nozzle of the gas cooling chamber of the intermediate facility, and is provided in a portion mainly composed of an external heat retaining structure. An exhaust gas side exhausted by a chimney draft when the incinerator is stopped is provided with a heat retaining device configured by a burner and a temperature control device for controlling the burner and maintaining the temperature in the intermediate facility at 130 ° C. or higher The temperature in the intermediate equipment is maintained at 130 ° C. or higher against the heat transfer to
[0013]
According to a second aspect of the present invention, there is provided a waste incineration method for a waste incinerator provided with an incinerator, an intermediate facility, a bag filter, and a chimney. There is provided a heat retention device composed of a burner provided in a part mainly composed of a structure, and a temperature control device for controlling the burner and maintaining the temperature in the intermediate equipment at 130 ° C. or higher, and when the incinerator is stopped The temperature in the intermediate facility is maintained at 130 ° C. or higher against the heat transfer to the exhaust gas side exhausted by the chimney draft, and the exhaust gas is passed through the bag filter at the start of combustion in the incinerator. It is characterized by.
[0014]
(Function)
In the invention according to claim 1 or claim 2 , the facility (the early gas burner) for maintaining the temperature in the intermediate facility at the time of the furnace shutdown at 130 ° C. or more is used as a cooling nozzle for the gas cooling chamber of the intermediate facility. Since there are few refractories after that, it is installed in a part mainly composed of an external heat insulation structure, so in the conventional method, the end of the incinerator is cooled by endothermic cooling from the intermediate equipment when the incinerator is stopped. Although it took several hours to wait until the exhaust gas temperature rises to the gas flow condition, the waiting time is no longer necessary, and after the burner temperature of the incinerator is raised, waste is thrown into the incinerator and exhaust gas is generated at the same time. The bag filter can be made to gas.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 shows a waste incinerator according to a first embodiment of the present invention (corresponding to claim 1 or claim 2 ).
[0016]
Between the incinerator 1 and the chimney 10, a combustion chamber 2, an intermediate facility 3, a bag filter 4, and an induction fan 5 are connected.
The incinerator 1 is provided with a hopper gate 11 for throwing in garbage, an ignition burner 12 and a movable firebed 13 in the same manner as a known incinerator, and the movable firebed 13 is thrown into the furnace. A drying zone 14 for drying the waste, a combustion zone 15 for burning the waste dried in the drying zone 14, and a post-combustion zone 16 for ashing the combustion residue of the waste burned in the combustion zone 15. It is divided into areas.
[0017]
In addition, the combustion chamber 2 located above the incinerator 1 is provided with blowers 30 and 31 for supplying secondary air and tertiary air, similarly to the known incinerator.
The intermediate facility 3 includes a gas cooling chamber 6 and air preheaters (heat exchangers) 7 and 8.
The gas cooling chamber 6 is provided with an early gas burner 17.
[0018]
The early gas burner 17 is provided on the downstream side of the gas cooling nozzle 9. The early gas burner 17 communicates with a heavy oil transfer pump (not shown). The early gas burner 17 and the heavy oil transfer pump are configured so that ON / OFF is controlled by a temperature control device 29 as described later.
Moreover, the intermediate equipment 3, the bag filter 4, and the induction fan 5 are in communication as follows.
[0019]
The gas cooling chamber 6 and the air preheater 7 are connected by a duct 18, the air preheater 7 and the air preheater 8 are connected by a duct 19, and the air preheater 8 and the bag filter 4 are connected by a duct 20. The bug filter 4 and the induction fan 5 communicate with each other through a duct 21, and the induction fan 5 and the chimney 10 communicate with each other through a duct 22.
[0020]
Further, the air preheater 8, the bag filter 4, and the induction fan 5 are communicated with each other by a bypass duct 23.
Switching valves 24 to 27 are arranged in the ducts 20 and 21 and the bypass duct 23.
Further, in the duct 20, a temperature sensor 28 that detects the temperature in the duct 20 when the incinerator 1 is stopped is disposed on the upstream side of the branching portion with the bypass duct 23. This temperature sensor 28 communicates with a temperature control device 29.
[0021]
The temperature control device 29 monitors whether or not the temperature in the duct 20 is maintained at 130 ° C. or higher based on a signal from the temperature sensor 28 that detects the temperature in the duct 20 when the incinerator 1 is stopped. When the temperature is lower than 0 ° C., the heavy oil transfer pump is driven to issue a command to ignite the early gas passage burner 17.
Next, the operation of this embodiment will be described.
[0022]
During normal operation, the switching valves 24 and 27 are opened and the switching valves 25 and 26 are closed by a control device (not shown). The unburned portion of the exhaust gas at about 950 ° C. burned in the combustion furnace 1 is reburned in the combustion chamber 2. Thereafter, it flows into the gas cooling chamber 6. In the gas cooling chamber 6, the air is cooled to 450 ° C. or less by water injection at the gas cooling nozzle 9, and then the air preheater 7 communicated via the duct 18 and the air preheater 7 communicated via the duct 19. The temperature is lowered by the air preheater 8. Thereafter, the exhaust gas is sent to the bag filter 4 by the induction fan 5. The bag filter 4 removes harmful substances such as dioxins and dust in the exhaust gas. The exhaust gas that has passed through the bag filter 4 is released from the chimney 10 into the atmosphere.
[0023]
Next, when the combustion furnace 1 is stopped, the switching valves 24 and 27 are closed and the switching valves 25 and 26 are opened by a control device (not shown). As a result, the entrance / exit of the bag filter 4 is closed and the duct 20 communicates via the bypass duct 23. This operation is a conventional means performed to ensure the safety of the bag filter 4.
On the other hand, the temperature control device 29 constantly obtains temperature information in the duct 20 by the temperature sensor 28 and monitors the temperature information from the temperature sensor 28.
[0024]
This will be described with reference to the flowchart shown in FIG.
The temperature control device 29 detects the temperature in the vicinity of the branch portion between the duct 20 and the bypass duct 23 and controls ON / OFF of the early gas burner 17 so that the temperature is maintained at 130 ° C. or higher.
When the temperature information from the temperature sensor 28 is 132 ° C. or higher (S1), the early gas burner 17 is turned off (S2), and the heavy oil transfer pump is turned off (S3).
[0025]
On the other hand, when the temperature information from the temperature sensor 28 is 130 ° C. or lower (S4), the heavy oil transfer pump is turned on (S5), and the early gas burner 17 is turned on (S6).
As a result, the inlet temperature of the bag filter 4 is always maintained at 130 ° C. or higher.
Since the inlet temperature of the bag filter 4 is controlled at 160 ° C. to 170 ° C. during normal operation, the bag filter 4 is always operated at 130 ° C. or higher.
[0026]
Therefore, the control of the flowchart of FIG. 2 is not limited to the conditions of rest, operation startup, steady state, and shutdown, but is always in an operable state.
As described above, according to the present embodiment, even when the combustion furnace 1 is in a dormant state, the temperature on the inlet side of the bag filter 4 is maintained at 130 ° C. or higher, so that the operation is resumed (operation startup). When the exhaust gas is sent through the duct 20, it can be sent into the bag filter 4 without going through the bypass duct 23 as in the conventional case.
[0027]
As described above, according to the present embodiment, the early gas passing burner 17 is provided in a portion mainly composed of the external heat retaining structure since the refractory after the gas cooling nozzle 9 is small and is provided mainly. As the temperature can be easily raised by the above-mentioned process, and only the heat radiation during the suspension is required, the gas passing through the bag filter 4 can be started from the start of the furnace pressure control by starting the induction fan 5.
[0028]
Moreover, even if the combustion furnace 1 is in a resting state, the ducts 18, 19, 20, 23 and the induction fan 5 are kept warm so that the temperature on the inlet side of the bag filter 4 is maintained at 130 ° C. or higher. Condensation in the ducts 18, 19, 20, 23 and the induction fan 5 does not occur, and the possibility that adhering dust accumulates in the ducts 18, 19, 20, 23 and the induction fan 5 is very small.
[0029]
In the present embodiment, it is conceivable to provide the early gas passing burner 17 in the combustion chamber 2.
In this case, since it is exposed to exhaust gas at 950 ° C., it is necessary to provide a shutter in front of the early gas burner 17 .
Next, an experimental example of this embodiment is shown.
[0030]
The amount of heat stored in the furnace refractory from the furnace stop moves to the exhaust gas side (exhaust gas exhausted by the chimney draft). This heat storage affects the startup time of the furnace and greatly affects the time during which the exhaust gas temperature at the inlet of the bag filter 4 rises. The time to increase the exhaust gas temperature to 130 ° C., which is the bag filter gas passing condition, becomes longer as the furnace downtime becomes longer. For example, as shown in Table 1, when the inlet temperature of the bag filter 4 is held and controlled as in this embodiment, gas can be passed along with the introduction of dust, and the dioxin at the time of start-up is reduced to a level equivalent to that at the steady state. be able to. Moreover, the activated carbon adsorption removal method using the bag filter 4 can also be utilized.
[Table 1]

Next, a waste incinerator according to a second embodiment of the present invention is shown based on FIG. 3 (corresponding to claim 1 ).
The present embodiment is an example in which the gas cooling chamber 6 </ b> A is applied to a waste incinerator separated from the combustion furnace 1. Here, in the gas cooling chamber 6A, the exhaust gas flows downward.
[0031]
The gas cooling chamber 6A communicates with the combustion chamber 2 via a duct 18a. The gas cooling chamber 6A communicates with the air preheater 7 through a duct 18b.
In the present embodiment, a temperature reducing tower 32 is provided between the air preheater 8 and the bag filter 4. The air preheater 8 and the temperature-decreasing tower 32 are connected via a duct 20a, and the temperature-decreasing tower 32 and the bag filter 4 are connected via a duct 20b.
[0032]
Furthermore, in this embodiment, switching control is performed by the three switching valves 24, 25, and 27.
Since other configurations are the same as those of the first embodiment shown in FIG. 1, the same components and members are denoted by the same reference numerals, and description thereof is omitted.
Also in the present embodiment, it is possible to achieve the same effects as the first embodiment.
[0033]
In addition, although the waste incinerator which concerns on this invention was demonstrated by embodiment shown in FIG. 1, FIG. 3, this invention is not limited to these, What kind of form will be sufficient if it is a waste incinerator provided with a bag filter? It goes without saying that it can also be applied to things.
Moreover, even if it exists in the installation provided with the boiler, this invention can anticipate the same effect by the same use. That is, the early gas burner 17 is provided at a predetermined position after the boiler, and the start-up can be used together with the boiler heating equipment (burner).
[0034]
Further, in the embodiment shown in FIG. 1 and FIG. 3, the case where the early gas burner 17 is provided on the downstream side of the gas cooling nozzle 9 in the gas cooling chambers 6 and 6A has been described, but the present invention is not limited thereto. The intermediate filter 3 may be provided anywhere as long as it is in the intermediate facility 3 located upstream of the bag filter 4.
[0035]
【The invention's effect】
As described above, according to the invention according to claim 1 or claim 2 , since the temperature in the intermediate facility when the incinerator is stopped is maintained at 130 ° C. or higher, the exhaust gas is passed through the bag filter simultaneously with the start-up. It becomes possible to make it.
[Brief description of the drawings]
FIG. 1 is a diagram showing a waste incinerator according to a first embodiment of the present invention.
FIG. 2 is a flowchart of a control device in the first embodiment.
FIG. 3 is a view showing a waste incinerator according to a second embodiment of the present invention.
[Explanation of symbols]
1 Incinerator 2 Combustion chamber 3 Intermediate equipment 4 Bag filter 5 Induction fan 6, 6A Gas cooling chamber 7, 8 Air preheater (heat exchanger)
9 Gas Cooling Nozzle 10 Chimney 17 Early Gas Burner 28 Temperature Sensor 29 Temperature Control Device

Claims (2)

Equipped with incinerator, intermediate equipment, bag filter and chimney,
There are few refractories after the cooling nozzle of the gas cooling chamber of the intermediate facility, and a burner provided in a part mainly composed of an external heat retaining structure and the burner are controlled to keep the temperature in the intermediate facility at 130 ° C. or higher. A thermal insulation device comprising a temperature control device is provided, and the temperature in the intermediate facility is maintained at 130 ° C. or higher against the heat transfer to the exhaust gas side exhausted by the chimney draft when the incinerator is stopped. Waste incinerator characterized by that. In a waste incineration method of a waste incinerator equipped with an incinerator, intermediate equipment, a bag filter and a chimney,
There are few refractories after the cooling nozzle of the gas cooling chamber of the intermediate facility, and a burner provided in a part mainly composed of an external heat retaining structure and the burner are controlled to keep the temperature in the intermediate facility at 130 ° C. or higher. A thermal insulation device comprising a temperature control device is provided, and the temperature in the intermediate facility is maintained at 130 ° C. or higher against the heat transfer to the exhaust gas side exhausted by the chimney draft when the incinerator is stopped. The exhaust gas is passed through the bag filter at the start of combustion in the incinerator.
Waste incineration method characterized by that.

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