JPH04115234U - Garbage incinerator exhaust equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To suppress and prevent the generation of dioxin by making slight improvements to existing equipment. [Structure] A gas cooling chamber 4 that injects water 5 to cool the exhaust gas is provided in the middle of the exhaust gas duct 2 that guides the exhaust gas generated in the garbage incinerator 1 to the chimney 3. An air preheater 11 is provided on the side to perform heat exchange between the primary air sent to the waste incinerator 1 and exhaust gas, and a dust collector 21 is provided on the outlet side of the air preheater 11 of the exhaust gas duct 2. A temperature adjustment air supply path 13 equipped with a temperature adjustment air control valve 14 to supply temperature adjustment air is connected between the dust collector 21 and the temperature of the exhaust gas on the inlet side of the dust collector 21 is detected. Air control valve 14 for temperature adjustment
A temperature controller 15 is provided to adjust the degree of opening.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to exhaust equipment for waste incinerators.

0002

[Conventional technology]

Generally, the temperature of 750 to 950℃ is generated by burning municipal waste in a garbage incinerator. The exhaust gas is first led to the gas cooling chamber through the exhaust gas duct, and is exhausted in the gas cooling chamber. In order to prevent high-temperature corrosion of equipment, water is sprayed to cool it to 300-350℃, The primary air for combustion is then led to an air preheater, where it is supplied to the incinerator. Heat is exchanged with the air, raising the temperature of the primary air to 200 to 250℃, and increasing the temperature of the primary air to 3 The temperature is lowered to 00℃, the dust is collected using an electrostatic precipitator, and then discharged from the chimney. Ru.

0003 The temperature of the exhaust gas at the inlet of the electrostatic precipitator is set at 300°C because the air To enable primary air to be preheated to 200 to 250°C in a preheater and An electrostatic precipitator that performs best at around 300℃ is selected based on the specific resistance value of dust. This is because it is used.

0004 By the way, dioxin is a highly toxic and well-known environmental pollutant. Incomplete combustion products such as municipal waste are also synthesized under the catalytic action of dust components. As shown in Figure 2, the dioxins are In recent years, it has been discovered that the highest amount of dust is generated at temperatures around 300 degrees Celsius inside aircraft cabins.

[0005] However, with the conventional waste incinerator exhaust equipment mentioned above, the exhaust at the entrance of the electrostatic precipitator is Since the gas temperature is set at 300℃, this part is the cause of dioxin generation. There is a risk that

[0006] Therefore, the temperature of the exhaust gas at the inlet of the electrostatic precipitator is kept below 300℃. In order to increase the amount of water injected into the gas cooling chamber, Consideration is being given to significantly lowering the temperature.

[0007]

[Problem that the idea aims to solve]

However, the temperature of the exhaust gas at the inlet of the electrostatic precipitator should be 300℃ or less. If you simply increase the amount of water injected into the gas cooling chamber in order to I had the following problem.

[0008] In other words, in order to increase the amount of water injected, the capacity of the gas cooling chamber, pump, nozzle, etc. In addition, if the amount of water injected into the gas cooling chamber is increased, It becomes difficult for the exhaust gas to completely evaporate the large amount of water that is injected, and the dust becomes damp. This may interfere with the operation of the gas cooling room or cause condensation on the exhaust equipment.

[0009] In addition, the exhaust gas temperature at the air preheater inlet also drops significantly, so the exhaust gas temperature in the gas cooling room is If the gas temperature is significantly lowered, the air preheater in the latter stage will heat the primary air to 200~200℃. It becomes impossible to preheat to 50°C.

0010 Furthermore, if the amount of water injected into the gas cooling chamber is increased, the amount of moisture in the exhaust gas or The proportion will increase significantly, making the exhaust equipment more susceptible to corrosion and However, the exhaust gas emitted from chimneys becomes white smoke and easily causes so-called visible pollution. Become.

[0011] Therefore, when applying it to an existing waste incinerator, it is necessary to The entire air system would have to be significantly remodeled.

0012 In view of the above-mentioned circumstances, the present invention has been developed to improve the efficiency of existing equipment by making slight improvements. To provide exhaust equipment for waste incinerators that can suppress and prevent the generation of oxins. The purpose is to

[0013]

[Means to solve the problem]

The invention of claim 1 is based on an exhaust gas duct that guides exhaust gas generated in a garbage incinerator to a chimney. A gas cooling chamber is installed in the middle of the exhaust gas duct to cool the exhaust gas by injecting water. At the exit side of the cooling room, heat exchange is performed between the primary air sent to the waste incinerator and the exhaust gas. An air preheater is installed, and a dust collector is installed on the outlet side of the air preheater in the exhaust gas duct to prevent air preheating. A temperature adjustment air control valve is installed between the dust collector and the dust collector to supply temperature adjustment air. In addition to connecting the air supply path for temperature adjustment, the temperature of the exhaust gas at the entrance of the dust collector is Features a temperature controller that detects the temperature and adjusts the opening of the air control valve. This is related to exhaust equipment for waste incinerators.

[0014] The invention of claim 2 is such that the suction side of the air supply path for temperature adjustment is located in a room where the temperature tends to be high. Rooms that are prone to oxygen deficiency, rooms that generate dust, and equipment that requires dust countermeasures. This applies to the exhaust equipment of at least one connected waste incinerator.

[0015]

[Effect]

According to the invention of claim 1, the exhaust gas generated in the waste incinerator is first passed through the gas cooling chamber. It is cooled by injecting water in the gas cooling chamber, and then the air preheater The air is guided through the air preheater and exchanged heat with the primary air that is sent to the waste incinerator. Furthermore, the temperature adjustment air sent through the temperature adjustment air supply path is mixed and cooled. After that, the dust is collected by a dust collector and finally released into the atmosphere through the chimney.

[0016] At this time, the temperature of the exhaust gas on the inlet side of the dust collector is detected by the temperature controller; The temperature of the exhaust gas on the inlet side of the dust collector is adjusted by adjusting the opening degree of the temperature adjustment air control valve. temperature is controlled to below 200°C.

[0017] According to the invention described in claim 2, a room that tends to get high temperature or a room that tends to lack oxygen. From at least one of the rooms where hazardous dust is generated or equipment that requires dust countermeasures. Temperature-adjusting air is fed to the exhaust gas duct via the temperature-adjusting air supply path.

[0018]

【Example】

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

[0019] FIG. 1 shows an embodiment of the present invention.

[0020] In the figure, 1 is a garbage incinerator for burning municipal waste, and 2 is a garbage incinerator 1 for urban use. This is an exhaust gas duct that guides exhaust gas generated by burning ash, etc. to the chimney 3.

[0021] A gas cooling chamber 4 is provided in the middle of the exhaust gas duct 2. A water supply path 6 for injecting water for exhaust gas cooling is connected to the A water flow control valve 7 is provided in the exhaust gas duct 2 to adjust the amount of water 5 flowing through the water supply path 6. A water flow control valve is installed on the outlet side of the gas cooling chamber 4 based on the temperature of the exhaust gas exiting the gas cooling chamber 4. A temperature controller 8 is provided to adjust the opening degree of 7.

[0022] Also, on the downstream side in the flow direction of exhaust gas from the connection part of temperature controller 8 of exhaust gas duct 2. , combustion is supplied from the primary blower 9 to the waste incinerator 1 via the primary air supply path 10. Air preheater 1 that performs heat exchange between primary air and exhaust gas to preheat primary air. 1 is installed, and a temperature adjustment blower 12 is installed on the outlet side of the air preheater 11 of the exhaust gas duct 2. Connect the temperature adjustment air supply path 13 that supplies temperature adjustment air, and The amount of temperature adjustment air flowing through the temperature adjustment air supply path 13 is adjusted in the middle of the supply path 13. A temperature regulating air regulating valve 14 is provided to control the temperature regulating air supply to the exhaust gas duct 2. The exhaust gas flowing through the exhaust gas duct 2 is located on the downstream side in the flow direction of the exhaust gas than the connecting portion of the passage 13. A temperature controller 15 that adjusts the opening degree of the temperature adjusting air regulating valve 14 based on the temperature of the In addition, the suction side of the temperature adjustment blower 12 is connected to the furnace that houses the waste incinerator 1. Rooms that tend to get hot, such as room 16, and rooms that tend to be oxygen deficient, such as wastewater treatment room 17. , rooms where dust is generated such as the ash removal room 18, the ash conveyor 19 and the ash bunker 2. Connect to equipment that requires measures against dust such as zero.

[0023] On the downstream side in the exhaust gas flow direction from the temperature controller 15 connection part of the exhaust gas duct 2, A bag filter type dust collector 21 is provided.

[0024] In addition, 22 in the figure is from the secondary blower 23 to the garbage incinerator 1, and the city inside the garbage incinerator 1. In order to promote the combustion of waste and to prevent the temperature inside the incinerator 1 from rising excessively. This is a secondary air supply path that supplies secondary air.

[0025] Next, the operation will be explained.

[0026] First, the set temperature of the temperature controller 8 is set to about 350°C, and the set temperature of the temperature controller 15 is set to about 350°C. The temperature should be 200℃ or less.

[0027] Then, the air is supplied from the primary blower 9 to the waste incinerator 1 via the primary air supply path 10. Municipal waste, etc. is burned in the waste incinerator 1.

[0028] The temperature of the exhaust gas generated when municipal waste is burned in the garbage incinerator 1 is 750~ 950℃, and the exhaust gas at 750 to 950℃ first passes through the exhaust gas duct 2. In order to prevent high-temperature corrosion of exhaust equipment in the gas cooling chamber 4, The water 5 from the water supply path 6 is injected to a temperature of 300 to 350℃, that is, 300℃ or more. cooled down.

[0029] At this time, the temperature controller 8 detects the temperature of the exhaust gas on the outlet side of the gas cooling chamber 4 and adjusts the water amount. By adjusting the opening degree of the valve 7, the temperature of the exhaust gas on the outlet side of the gas cooling chamber 4 can be adjusted to 30°C. The amount of water 5 injected into the gas cooling chamber 4 is controlled so that the temperature is 0 to 350°C.

[0030] In this way, the temperature of the exhaust gas on the outlet side of the gas cooling chamber 4 is kept at 300 to 350°C, the same as before. The amount of water 5 injected into the gas cooling chamber 4 does not need to be increased. As a result, it is possible to eliminate the need to increase the capacity of the gas cooling chamber 4, and First, the water 5 injected as before can be completely evaporated inside the gas cooling chamber 4. .

[0031] The exhaust gas cooled to 300 to 350°C, that is, 300°C or more in the gas cooling chamber 4, is Next, the primary air is guided to the air preheater 11 from the primary blower 9 in the air preheater 11. Heat exchange with primary air for combustion supplied to the waste incinerator 1 via the supply path 10 As before, the temperature of the primary air is raised to 200 to 250℃, and the temperature of the primary air is increased to 30℃. The temperature is lowered to 0°C.

[0032] The exhaust gas whose temperature has been lowered to 300°C by the air preheater 11 is then sent to a temperature-adjusting air blower. The temperature adjustment air sent from the machine 12 through the temperature adjustment air supply path 13 is mixed. It is immediately cooled down to 200℃ or less, and is used for exhaust gas and temperature adjustment by cooling. The air mixture is reduced in volume.

[0033] At this time, the amount of temperature adjustment air injected into the exhaust gas duct 2 is determined by the temperature controller 15. detects the temperature of the exhaust gas on the downstream side of the connection part of the temperature adjustment air supply path 13 of the exhaust gas duct 2. Temperature adjusting air is supplied so that the temperature of the exhaust gas on the downstream side of the connection is 200℃ or less. It is controlled by adjusting the opening degree of the regulating valve 14.

[0034] In addition, the suction side of the temperature adjustment blower 12 is connected to the furnace chamber 16 etc. that accommodates the waste incinerator 1. Rooms that are prone to high temperatures, rooms that are prone to oxygen deficiency such as wastewater treatment room 17, and ash removal Rooms where dust is generated such as room 18, dust conveyor 19 and ash bunker 20, etc. Since it is connected to equipment that requires dust countermeasures, it is necessary to install it separately in each room and equipment. Ventilators and dust collectors that were previously installed will be consolidated and become unnecessary.

[0035] Exhaust gas cooled to below 200°C has sufficient dust collection performance with conventional electrostatic precipitators. Since this is not possible, a bag filter type dust collector 21 is installed to collect exhaust gas and air After the mixed gas is guided to the dust collector 21 and collected by the dust collector 21, the chimney 3 discharge from.

[0036] In this way, the temperature of the exhaust gas that comes out of the air preheater 11 and is introduced into the dust collector 21 is controlled. By immediately cooling the dust collector to below 200°C with maintenance air, the dust collector 21 The generation of dioxin is suppressed and prevented, and the cooling at this time reduces the temperature. The volumes of conditioning air and exhaust gas are reduced, so even if the actual gas volume increases, it will be smaller than before. Therefore, there is no need to increase the capacity of the dust collector 21 so much.

[0037] Moreover, by mixing temperature-adjusting air with the exhaust gas, the moisture concentration in the gas is reduced. As the temperature tends to decrease, visible pollution due to condensation, corrosion, and white smoke is less likely to occur. Become.

[0038] Note that the present invention is not limited to the above-mentioned embodiments, and can be applied to existing furnaces. It is also possible to use an electrostatic precipitator by cooling it with air to about 250℃. However, other changes may be made without departing from the gist of the invention. Of course.

[0039]

[Effect of the idea]

As explained above, according to the waste incinerator exhaust equipment according to the invention of claim 1, , by mixing temperature-adjusting air with the exhaust gas at the dust collector inlet. Since the temperature can be lowered to around 200℃, most of the existing equipment has to be modified. It is possible to suppress and prevent the generation of dioxins without Compared to increasing the amount of water injected into the cooling chamber, the primary air Can be preheated to ℃ and prevents problems such as condensation, corrosion, and visible pollution. This has the excellent effect of being able to.

[0040] According to the waste incinerator exhaust equipment according to the invention of claim 2, a ventilation system and a dust collector are not required. It has the excellent effect of being able to consolidate and eliminate the need.

[Brief explanation of drawings]

FIG. 1 is an overall system diagram of an embodiment of the present invention.

FIG. 2 is a graph showing the relationship between temperature and amount of dioxin generated.

[Explanation of symbols]

1 Garbage incinerator 2 Exhaust gas duct 3 chimney 4 Gas cooling room 5 Water 10 Primary air supply path 11 Air preheater 13 Air supply path for temperature adjustment 14 Air control valve for temperature adjustment 15 Temperature controller 16 Furnace room 17 Wastewater treatment room 18 Ash removal room 19 Ash conveyor 20 Ash Banka 21 Dust collector

Claims (2)

[Scope of utility model registration request] [Claim 1] A gas cooling chamber that injects water to cool the exhaust gas is provided in the middle of the exhaust gas duct that leads the exhaust gas generated in the garbage incinerator to the chimney, and a garbage incineration chamber is provided on the outlet side of the gas cooling chamber of the exhaust gas duct. An air preheater is installed to exchange heat between the primary air fed to the furnace and the exhaust gas, a dust collector is installed on the outlet side of the air preheater in the exhaust gas duct, and temperature adjustment air is installed between the air preheater and the dust collector. In addition to connecting a temperature adjustment air supply path equipped with a control valve to supply temperature adjustment air,
1. Exhaust equipment for a waste incinerator, characterized by being equipped with a temperature controller that detects the temperature of exhaust gas on the inlet side of a dust collector and adjusts the opening degree of an air control valve for temperature adjustment. [Claim 2] Connect the suction side of the air supply path for temperature adjustment to at least one of the following: a room that tends to get hot, a room that tends to lack oxygen, a room that generates dust, a device that requires dust countermeasures, etc. The exhaust equipment for a waste incinerator according to claim 1.