JP2009192091A - Carbonizing gasification incineration device and incineration disposal method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbonizing gasification incineration device and an incineration disposal method capable of saving a time and fuel necessary for warming while achieving clean exhaust. <P>SOLUTION: In this carbonizing gasification incineration device, the inside of a combustion furnace 3 is induced by an induction fan 31, and fuel is burned by a combustion device 25 prior to the ignition of waste A, and an exhaust flow rate of an exhaust gas discharged from the combustion furnace 3 by a gate damper 26 is controlled to a first flow rate most limited within a range that the generation of a carbon monoxide in the combustion furnace 3 is a threshold or small, in a warming operation for warming a temperature in the combustion furnace 3 to be higher than a first temperature enabling the thermal decomposition of dioxin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In recent years, wastes contain many chlorine components such as vinyl chloride. Therefore, incinerators that incinerate these wastes produce nitrogen oxides (NOx) and carbon monoxide during incineration. Air pollutants such as (CO) and dioxins can be generated. For this reason, certain environmental standards have been formulated to reduce emissions for these air pollutants.

  In particular, dioxins generated by incineration of waste are incomplete such as the chlorine liberated from the waste and incomplete resin when the waste containing chlorine is burned at a temperature of about 250 to 350 ° C. The hydrocarbons produced by combustion react with heavy metals contained in the waste as catalysts to produce dioxins.

  In order to prevent discharge of dioxins due to incineration of the waste, it is effective to cause the waste to stay at a temperature of 800 ° C. or higher for 2 seconds or more to completely thermally decompose the generated dioxins. It is said that.

  By the way, the present applicant, as an apparatus for incinerating waste such as waste tires while preventing the discharge of dioxins, stores the waste and burns a part of the waste, Proposed a dry distillation gasification and incineration treatment apparatus comprising a dry distillation furnace for producing a combustible gas by carbonizing the remainder of the waste by combustion heat and a combustion furnace for introducing the combustible gas from the dry distillation furnace to completely burn it (For example, refer to Patent Document 1).

In the above apparatus, the temperature in the combustion furnace was raised to 800 ° C. or higher where dioxins can be thermally decomposed by combustion of other combustion, and then the waste was ignited to generate combustible gas. A combustible gas is burned together with other fuels in a combustion furnace. When the combustion furnace temperature can be maintained at a stable temperature higher than 800 ° C. by burning only the combustible gas, the combustion of the other fuel is terminated. This prevents the discharge of dioxins by setting the temperature in the combustion furnace to 800 ° C or higher after the start of dry distillation of waste until the combustible gas spontaneously stabilizes and continues to burn. Yes.
Japanese Patent No. 4005770

  However, in the apparatus, it is necessary to raise the temperature in the combustion furnace to 800 ° C. prior to the ignition of the waste. Therefore, it takes time for such warming, so that the substantial operation time of the apparatus is divided and warming is required. The disadvantage is that the fuel is bulky and the running cost of the device is high.

  Therefore, in order to eliminate such inconveniences, an object of the present invention is to provide a dry distillation gasification incineration processing apparatus and an incineration processing method that can save time and fuel required for warm air while realizing clean exhaust. To do.

  In order to achieve the above object, the dry distillation gasification incineration apparatus of the present invention stores waste, combusts by combusting a part of the waste with the heat of combustion while burning a part of the waste. A carbonization furnace for generating a combustible gas, a combustion furnace for combusting a combustible gas introduced from the carbonization furnace, and an oxygen required for the combustion according to the amount of the combustible gas introduced into the combustion furnace to the combustion furnace Combustion oxygen supply means to be supplied, combustion furnace temperature detection means for detecting the temperature in the combustion furnace, and combustion detected by the combustion temperature detection means after the combustion of the combustible gas in the combustion furnace is started A dry distillation oxygen supply means for adjusting an oxygen supply amount to the dry distillation furnace so as to maintain a temperature in the furnace at a preset temperature; a combustion means for burning fuel in the combustion furnace; Flow control means for controlling the flow rate of exhaust A gasification incineration processing apparatus comprising an induction means for inducing combustion exhaust in the combustion furnace, wherein the combustion means induces the inside of the combustion furnace by the induction means prior to ignition of the waste and the combustion means Combustion exhaust exhausted from the combustion furnace by the flow rate control means during a warm-up operation in which the fuel is combusted and the temperature in the combustion furnace is warmed to a temperature higher than a first temperature at which dioxins can be thermally decomposed Is controlled to a first flow rate that is most limited within a range in which the amount of carbon monoxide generated in the combustion furnace is equal to or less than a threshold value.

  According to the dry distillation gasification incineration processing apparatus of the present invention, the exhaust flow rate of the combustion exhaust discharged from the combustion furnace is limited within a range where the amount of carbon monoxide generated in the combustion furnace is equal to or less than the threshold value. Therefore, generation of carbon monoxide can be suppressed from the time of warm-up operation, and clean exhaust can be realized.

  Furthermore, by limiting the exhaust flow rate of the combustion exhaust, the combustion exhaust stays in the combustion furnace, and the outflow of heat accompanying the exhaust is suppressed. That is, the combustion heat generated by the combustion of the fuel flows into the combustion furnace, and the generated combustion heat contributes to the heating of the combustion furnace, so that the temperature increase of the combustion furnace can be promoted. As a result, it is possible to shorten the time required for warming up and save fuel.

  Further, in the dry distillation gasification incineration processing apparatus of the present invention, when the temperature in the combustion furnace becomes equal to or higher than the first temperature by the combustion means, the waste is ignited to start dry distillation. At the start of an auxiliary combustion operation in which the combustible gas is combusted with the fuel in the combustion furnace, the flow rate of the combustion exhaust discharged from the combustion furnace by the flow rate control means is larger than the first flow rate and smaller than the maximum flow rate. The second flow rate is controlled.

  According to the dry distillation gasification incineration apparatus of the present invention, when the waste is ignited and the dry distillation is started while the exhaust flow rate of the combustion exhaust gas is limited to the same first flow rate as in the warm-air operation, the combustion is combustible by the progress of the dry distillation There is a possibility that the amount of sex gas generated will increase and it will not be possible to cope with combustion exhaust due to the combustion. On the other hand, if the discharge flow rate of the combustion exhaust is set to the maximum flow rate at the start of the auxiliary combustion operation, the temperature of the combustion furnace set to the first temperature or higher is caused by the supply of the combustible gas introduced into the combustion furnace and the oxygen necessary for the combustion. Can be reduced.

  Therefore, by controlling the discharge flow rate of the combustion exhaust discharged from the combustion furnace to the second flow rate larger than the first flow rate at the start of the auxiliary combustion operation, the fire bed of the ignited waste spreads greatly. Even when the generation amount of the combustible gas fluctuates transiently, it is possible to cope with combustion exhaust due to combustion of the combustible gas. Furthermore, by making the second flow rate smaller than the maximum flow rate, it is possible to suppress a decrease in the temperature of the combustion furnace that has been brought to the first temperature or higher by the auxiliary combustion operation, and save the fuel required for the auxiliary combustion operation and reduce the running cost. Reduction can be achieved.

  Here, the second flow rate may be controlled in proportion to a flow rate (a flow rate that also includes transient fluctuations) that can be predicted and dealt with fluctuations in the amount of combustible gas generated, but is constant as follows. It is preferable to use a flow rate.

  That is, in the dry distillation gasification incineration processing apparatus of the present invention, the flow rate control means reduces the rate of combustion of the fuel by the combustion means by the temperature in the combustion furnace during the auxiliary combustion operation as the second flow rate. However, the increase in the generation amount of the combustible gas causes the second temperature to be higher than the first temperature and lower than the stable temperature at which the temperature of the combustion furnace is stably maintained by the combustion of only the combustible gas. The flow rate is controlled to be the most limited within a range in which the amount of carbon monoxide generated in the combustion furnace when maintained is within a threshold value.

  According to the dry distillation gasification incineration processing apparatus of the present invention, the discharge flow rate (second flow rate) of combustion exhaust at the start of the auxiliary combustion operation increases the amount of combustible gas generated with the progress of dry distillation of waste. Stipulates a stage where the combustion furnace temperature is maintained at the second temperature by the combustible gas even when the fuel combustion rate is reduced (a stage where dry distillation proceeds and a certain amount of combustible gas is expected to be generated) At this stage, the amount of carbon monoxide generated in the combustion furnace is limited within a range not exceeding the threshold value. In this way, at the start of the auxiliary combustion operation, the flow rate is controlled in advance so as to correspond to the combustion exhaust in the next stage in the auxiliary combustion operation (the stage where dry distillation proceeds and a certain amount of combustible gas is expected to be generated). Therefore, even when the amount of flammable gas generated changes transiently, the combustion exhaust from the combustion of the flammable gas is excessively retained in the combustion furnace and shifts to a state where carbon monoxide is easily generated. You can avoid that.

  Further, in the dry distillation gasification incineration apparatus of the present invention, even if the temperature in the combustion furnace in the auxiliary combustion operation reduces the rate of combustion of the fuel by the combustion means, the amount of generated combustible gas is increased. When the combustion temperature of the combustion furnace is maintained at a second temperature lower than the stable temperature at which the temperature of the combustion furnace is stably maintained by the combustion of only the combustible gas, The discharge flow rate of the combustion exhaust discharged from the furnace is controlled to the maximum flow rate.

  According to the dry distillation gasification incineration apparatus of the present invention, in the auxiliary combustion operation, the amount of combustible gas generated increases with the progress of dry distillation of waste, and the temperature of the combustion furnace is increased by the combustion heat of only the combustible gas. Is continued until the stable temperature can be maintained, but even if the combustion rate of the fuel is reduced, the temperature of the combustion furnace is maintained at the second temperature by the combustible gas (the dry distillation proceeds to a certain level). At the stage where the amount of combustible gas generation is expected), the exhaust flow rate of the combustion exhaust discharged from the combustion furnace is set to the maximum flow rate in anticipation of the subsequent increase in the amount of combustible gas generation. As a result, even when the carbonization of waste is progressing rapidly and the amount of combustible gas generated increases rapidly, the combustion exhaust from combustion of the combustible gas is excessively retained in the combustion furnace, and carbon monoxide is generated. It is possible to avoid shifting to a state where it is likely to occur, and to cope with combustion exhaust due to increased combustion of combustible gas.

  Furthermore, in the dry distillation gasification incineration processing apparatus of the present invention, the flow rate control means includes a pipe area adjusting means that is provided in a pipe line on the outlet side of the combustion furnace and adjusts the area of the pipe line. The means controls the discharge flow rate of the combustion exhaust discharged from the combustion furnace by adjusting the area of the pipe line.

  According to the dry distillation gasification incineration apparatus of the present invention, the exhaust flow rate of the combustion exhaust discharged from the combustion furnace is controlled by adjusting the pipe area. As a result, the flow rate control means can be simply configured, and the time and fuel required for warming up can be saved while realizing clean exhaust.

  Moreover, in the dry distillation gasification incineration apparatus of the present invention, the attraction means changes a pressure for inducing combustion exhaust in the combustion furnace in accordance with an operating state.

  According to the dry distillation gasification incineration apparatus of the present invention, the amount of exhaust discharged from the combustion furnace can be adjusted by changing the pressure for inducing combustion exhaust according to the operating state. For example, during warm-up operation, in addition to limiting the exhaust flow rate of combustion exhaust exhausted from the combustion furnace by the flow rate control means, it is possible to suppress an increase in the exhaust amount by reducing the pressure to be attracted. Therefore, combustion exhaust can be retained in the combustion furnace, and the time required for warming can be shortened and fuel can be saved. On the other hand, at the time of the auxiliary combustion operation, by maximizing the pressure to be attracted, it is possible to secure a discharge amount that can correspond to the combustion exhaust due to the combustion of the combustible gas, and to maintain the combustion state of the combustible gas well. It becomes possible.

In order to achieve the above object, the incineration processing method of the present invention ignites the waste contained in the dry distillation furnace to burn a part of the waste, and the other part of the waste is burned by the combustion heat. A combustibility introduced into the combustion furnace when the combustible gas is combusted in the combustion furnace, comprising a step of dry distillation and a step of introducing and combusting the combustible gas generated by the carbonization into the combustion furnace. Depending on the amount of gas, oxygen required for the combustion is supplied to the combustion furnace to burn the combustible gas, and the combustion furnace causes the combustible gas to burn and the temperature in the combustion furnace is changed according to the temperature change in the combustion furnace. An incineration processing method for controlling the amount of oxygen supplied to a dry distillation furnace and adjusting the amount of combustible gas generated by the dry distillation to maintain the temperature in the combustion furnace at a preset temperature, Prior to the ignition of the waste, the inside of the combustion furnace is attracted and the front During the warm-up operation in which the fuel is combusted and the temperature in the combustion furnace is warmed to a temperature equal to or higher than the first temperature at which dioxins can be thermally decomposed, the discharge flow rate of the combustion exhaust discharged from the combustion furnace is minimized. A first step of controlling, and when the temperature in the combustion furnace becomes equal to or higher than the first temperature, the waste is ignited to start dry distillation, and the generated combustible gas is generated in the combustion furnace. A second step of controlling the discharge flow rate of the combustion exhaust discharged from the combustion furnace to an intermediate flow rate larger than the minimum flow rate and smaller than the maximum flow rate at the start of the auxiliary combustion operation for burning together with the fuel; Even if the temperature in the furnace decreases the combustion rate of the fuel, the temperature of the combustion furnace is not less than the first temperature due to an increase in the amount of combustible gas generated, and the temperature of the combustion furnace is only due to combustion of the combustible gas. Stable temperature that can be maintained stably When maintained at a low temperature of the second temperature, and executes a third step of controlling the discharge flow rate of the combustion exhaust gas discharged from the combustion furnace to the maximum flow rate in order.

  According to the incineration processing method of the present invention, the exhaust flow rate of the combustion exhaust gas is limited to the minimum flow rate during the auxiliary combustion operation, so that the combustion exhaust gas stays in the combustion furnace, and the outflow of heat accompanying the exhaust gas is suppressed. As a result, it is possible to shorten the time required for warming up and save fuel.

  In addition, by controlling the discharge flow rate of the combustion exhaust discharged from the combustion furnace to an intermediate flow rate that is larger than the minimum flow rate at the start of the auxiliary combustion operation, the fire bed of the ignited waste spreads greatly, and the combustible gas Even when the amount of generated fluctuates transiently, it is possible to cope with combustion exhaust by combustion of the combustible gas. In addition, by making the intermediate flow rate smaller than the maximum flow rate, it is possible to suppress a decrease in the temperature of the combustion furnace that has been brought to the first temperature or higher by the auxiliary combustion operation, saving fuel required for the auxiliary combustion operation and reducing running costs. Can be achieved.

  Further, even when the fuel combustion rate is reduced, the temperature of the combustion furnace is maintained at the second temperature by the combustible gas (at the stage where dry distillation proceeds and a certain amount of combustible gas is expected to be generated). By setting the discharge flow rate of the combustion exhaust discharged from the combustion furnace to the maximum flow rate, even when the progress of dry distillation of waste is rapid and the generation amount of the combustible gas increases rapidly, the combustible gas It is possible to avoid that the combustion exhaust due to combustion is excessively retained in the combustion furnace and shift to a state where carbon monoxide is easily generated, and it is possible to cope with the combustion exhaust due to the increased combustion of the combustible gas.

  Thus, according to the incineration processing method of the present invention, it is possible to save time and fuel required for the warm-up operation and the auxiliary combustion operation while realizing clean exhaust.

  Next, the embodiment of the present invention will be described in more detail with reference to FIG. 1 and FIG. FIG. 1 is a system configuration diagram showing an embodiment of a dry distillation gasification incineration apparatus of the present invention, and FIG. 2 is a combustion temperature in a combustion furnace and a gate in a waste incineration method by the apparatus of this embodiment. It is a graph which shows the time-dependent change of the opening degree of a damper, and the attraction pressure by an attraction fan.

  As shown in FIG. 1, the dry distillation gasification incineration apparatus of this embodiment includes a dry distillation furnace 1 containing waste A, which is a mixture of various wastes mainly including waste tires, and the dry distillation furnace 1. And a combustion furnace 3 connected through a gas passage 2. On the upper surface of the dry distillation furnace 1, an input port 5 having an openable / closable input door 4 is formed, and waste A such as waste tires can be input into the dry distillation furnace 1 from the input port 5. In the state where the charging door 4 is closed, the inside of the carbonization furnace 1 is substantially cut off from the outside.

  A water jacket 6 isolated from the inside of the dry distillation furnace 1 is formed on the outer periphery of the dry distillation furnace 1 as a cooling structure. The water jacket 6 is supplied with water by a water supply device (not shown) so that the amount of water inside is maintained at a predetermined water level.

  A lower part of the dry distillation furnace 1 is formed in a truncated cone shape protruding downward, and an empty space 7 isolated from the inside of the dry distillation furnace 1 is formed in an outer peripheral part of the lower part of the truncated cone shape. The empty chamber 7 communicates with the inside of the dry distillation furnace 1 through a plurality of air supply nozzles 8 provided on the inner wall portion of the dry distillation furnace 1.

  A dry distillation oxygen supply path 9 is connected to the empty chamber 7 below the dry distillation furnace 1. The dry distillation oxygen supply path 9 is connected via a main oxygen supply path 10 to an oxygen (air) supply source 11 constituted by a pushing fan or the like. A control valve 12 is provided in the dry distillation oxygen supply path 9, and the opening degree of the control valve 12 is controlled by a valve driver 13. In this case, the valve driver 13 is controlled by a control device 14 configured by an electronic circuit including a CPU and the like.

  Furthermore, an ignition device 15 for igniting the waste A accommodated in the dry distillation furnace 1 under the control of the control device 14 is attached to the lower portion of the dry distillation furnace 1. The ignition device 15 is composed of an ignition burner or the like, and supplies a combustion flame to the waste A by burning the fuel supplied from the fuel supply device 16 in which fuel such as heavy oil is stored through the fuel supply path 17. To do.

  The combustion furnace 3 includes a burner unit 18 that mixes combustible gas generated by dry distillation of waste A and oxygen (air) necessary for complete combustion, and a combustion unit 19 that combusts the combustible gas mixed with oxygen. The combustion part 19 communicates with the burner part 18 on the tip end side of the burner part 18. A gas passage 2 is connected to the rear end portion of the burner portion 18, and combustible gas generated by dry distillation of the waste A in the carbonization furnace 1 is introduced into the burner portion 18 through the gas passage 2.

  A vacant chamber 20 isolated from the inside of the burner portion 18 is formed on the outer peripheral portion of the burner portion 18, and the vacant chamber 20 is inserted into the burner portion 18 through a plurality of nozzle holes 21 formed in the inner peripheral portion of the burner portion 18. It communicates with the inside. A combustion oxygen supply path 22 branched from the main oxygen supply path 10 is connected to the vacant chamber 20. A control valve 23 is provided in the combustion oxygen supply path 22, and the opening degree of the control valve 23 is controlled by a valve driver 24. In this case, the valve driver 24 is controlled by the control device 14.

  At the rear end portion of the burner portion 18, a combustion device 25 that is controlled by the control device 14 and burns fuel such as heavy oil supplied from the fuel supply device 16 via the fuel supply passage 17 (to the combustion means of the present invention). Equivalent) is attached. The combustion device 25 is composed of an ignition burner or the like, and burns while adjusting the fuel supply amount stepwise. For example, in the combustion apparatus 25 of the present embodiment, it is possible to switch between high temperature combustion with a large amount of fuel supply and low temperature combustion with a small amount of fuel supply. The combustion device 25 is also used when igniting the combustible gas introduced into the burner unit 18.

  A cooling furnace (hot water boiler) 27 that cools the combustion exhaust gas burned in the combustion furnace 3 is attached to the tip of the combustion part 19. The cooling furnace 27 is supplied with water by a water supply device (not shown), and the hot water heated in the cooling furnace 27 using the combustion heat of waste can be used for air conditioning or the like.

  On the outlet side of the cooling furnace 27, a duct 26 a that discharges the cooled combustion exhaust gas is provided, and is connected to one end of the cooling tower 28. The duct 26a is provided with a gate damper 26 (pipe area adjusting means of the present invention). The opening degree of the gate damper 26 is arbitrarily adjusted by the control device 14 between 0% and 100%.

  The cooling tower 28 includes a spray 28a that sprays the combustion exhaust from the cooling furnace 27, and is connected to a water supply device (not shown) that supplies cooling water to the spray and an air compressor.

  The other end of the cooling tower 28 is connected to one end of the bag filter 29 through a duct 26b, and slaked lime 29a and activated carbon 29b are mixed in the combustion exhaust gas sent from the cooling tower 28 to the bag filter 29. Desulfurization and deodorization are performed.

  The bag filter 29 includes a filter unit (not shown) and a recovery unit that recovers ash and the like separated from the exhaust gas by the filter unit, and an air compressor for cleaning the filter unit is connected to the filter unit.

  The other end of the bag filter 29 is connected to the chimney 30 via a duct 26c. Between the bag filter 29 and the chimney 30, there is provided an induction fan 31 (corresponding to the attraction means of the present invention) that induces the combustion exhaust in the combustion furnace 3 to the chimney 30 via the ducts 26a to 26c. The combustion exhaust is discharged from the chimney 30 through the induction fan 31 into the atmosphere. The induction fan 31 is controlled by the control device 14 so that the pressure for inducing the combustion exhaust in the combustion furnace 3 becomes a desired pressure according to the operating state of the device. Sensors for detecting a hydrogen chloride concentration and a carbon monoxide concentration (not shown) are respectively attached to the outlet of the chimney 30, and the hydrogen chloride concentration and the carbon monoxide concentration of the combustion exhaust exhausted from the chimney 30 are detected. Be monitored.

Further, in the apparatus of the present embodiment, a temperature sensor 32 for detecting the temperature T ₁ in the dry distillation furnace 1 is attached to the upper part of the dry distillation furnace 1, and the temperature T ₂ in the combustion furnace 3 is detected in the combustion furnace 3. A temperature sensor 33 is attached at a position facing the tip of the burner portion 18. Detection signals from the temperature sensors 32 and 33 are input to the control device 14.

  Next, a waste incineration method using the apparatus of this embodiment will be described with reference to FIGS. 1 and 2.

  In the apparatus shown in FIG. 1, when incinerating the waste A, first, the charging door 4 of the dry distillation furnace 1 is opened, and the waste A is input into the dry distillation furnace 1 from the charging port 5. The waste A is a mixture of various wastes mainly waste tires, and when the combustible gas generated by dry distillation in the dry distillation furnace 1 is stably burned, its combustion temperature is 800 ° C. In this embodiment, the combustion temperature is further adjusted so as to have a calorific value of 850 ° C. or higher.

  Next, after closing the charging door 4 and sealing the inside of the dry distillation furnace 1, prior to the ignition of the waste A, the controller 14 operates the combustion device 25 of the combustion furnace 3 in a high-temperature combustion state, The warm-up operation by burning the fuel is started.

Specifically, in the graph showing the time change shown in FIG. 2, the combustion of the fuel is started at time t _0. At this time, the controller 14 sets the attraction pressure by the attraction fan 31 to the maximum pressure Pmax. Then, when the opening degree of the gate damper 26 is set to the maximum opening degree OPmax by the control device 14, the discharge flow rate of the combustion exhaust discharged from the combustion furnace 3 is controlled to the maximum flow rate.

  This is to stabilize the combustion state of the fuel so that the induction pressure by the induction fan 31 at the start of fuel combustion (at the start of warm-up operation) is the maximum pressure Pmax and the discharge flow rate of the combustion exhaust gas is the maximum flow rate. That is, since the inside of the combustion furnace 3 is cooled at the start of fuel combustion, under such circumstances, if the discharge flow rate of the combustion exhaust gas is limited, the fuel sprayed from the burner 18 is difficult to vaporize and easily causes poor combustion. Therefore, at the start of the warm-up operation, the combustion exhaust is forcibly discharged from the combustion furnace 3 and the fuel sprayed from the burner 18 is easily vaporized, thereby avoiding the possibility of poor combustion.

Next, the temperature T in the combustion furnace 3 gradually increases due to the combustion of the fuel, and when the temperature T detected by the temperature sensor 33 reaches 100 ° C. at time t ₁ , the controller 14 attracts the attracting pressure by the attracting fan 31. Is set to the minimum pressure Pmin. Then, when the opening degree of the gate damper 26 is set from the maximum opening degree OPmax to the minimum opening degree OPmin by the control device 14, the first flow rate (the flow rate at which the exhaust gas discharged from the combustion furnace 3 is minimized) ( (Minimum flow rate).

  The first flow rate most restricts the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace 3 in a range where the concentration of carbon monoxide contained in the combustion exhaust exhausted from the chimney 30 is not more than a predetermined regulation value. Flow rate. Then, the first flow rate is realized from the relationship between the gate damper 26 and the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace 3 (in which the attraction pressure is below the minimum pressure Pmin) defined in advance by a map or a table. The minimum opening OPmin of the gate damper 26 is determined.

  Thus, by controlling the discharge flow rate of the combustion exhaust discharged from the combustion furnace 3 to the first flow rate, it is possible to suppress the generation of carbon monoxide in the warm-up operation and to realize clean exhaust. Furthermore, by restricting the exhaust flow rate of the combustion exhaust, the combustion exhaust stays in the combustion furnace 3, and the outflow of heat accompanying the exhaust is suppressed. Therefore, the combustion heat generated by the combustion of the fuel is transferred into the combustion furnace 3, and the heated combustion heat contributes to the heating of the combustion furnace, so that the temperature rise of the combustion furnace 3 can be promoted. Savings.

  In a specific comparative experiment conducted by the inventor of the present application, when the discharge flow rate of the combustion exhaust discharged from the combustion furnace 3 was controlled to the first flow rate, the flow rate was maintained at the maximum flow rate under the same conditions. Compared to the case, the warm-up time (the time from the start of warm-up operation until the temperature of the combustion furnace 3 reaches 800 ° C.) is shortened to ¼ to ５, and the combustion consumption required for warm-up is also ¼. It has been found that it can be suppressed to ˜1 / 5.

Then, when the temperature T in the combustion furnace 3 rises due to combustion of the fuel, the temperature T detected by the temperature sensor 33 at time t ₂ is more than 800 ° C. (corresponding to a first temperature of the present invention), the control The ignition device 15 of the dry distillation furnace 1 is operated by the device 14 to ignite the waste A, and an auxiliary combustion operation is started in which the combustible gas generated by partial combustion of the waste A is combusted in the combustion furnace 3 together with the fuel. The

  In synchronization with the start of the auxiliary combustion operation, the controller 14 sets the attraction pressure by the attraction fan 31 to the maximum pressure Pmax. Then, the control device 14 sets the opening degree of the gate damper 26 to an intermediate opening degree OPmid between the maximum opening degree OPmax and the minimum opening degree OPmin, whereby the exhaust flow rate of the combustion exhaust discharged from the combustion furnace 3 is set. Is controlled to a second flow rate (intermediate flow rate) between the maximum flow rate and the first flow rate (minimum flow rate).

  As will be described later, the second flow rate is such that the temperature in the combustion furnace 3 is 835 ° C. (e.g., according to the present invention) even if the combustion of the fuel by the combustion device 25 is switched to low-temperature combustion due to an increase in the amount of combustible gas generated. It is set based on the predicted combustion exhaust that will be exhausted from within the combustion furnace 3 when it is maintained at (corresponding to the second temperature). That is, the second flow rate is exhausted from the combustion furnace 3 in a range where the concentration of carbon monoxide contained in the predicted combustion exhaust is not more than a predetermined regulation value when the predicted combustion exhaust is exhausted from the chimney 30. The exhaust flow rate of the combustion exhaust is set to the most restrictive flow rate. The predicted combustion exhaust gas is calculated based on the amount of combustible gas generated that is statistically or empirically predicted from the size of the dry distillation furnace 1, the type of the waste A, or the like. Then, the second flow rate is realized from the relationship between the gate damper 26 and the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace 3 (provided that the attraction pressure is below the minimum pressure Pmax) defined in advance by a map or table. An intermediate opening OPmid of the gate damper 26 is determined.

  Thus, at the start of the auxiliary combustion operation, by controlling the exhaust flow rate of the combustion exhaust discharged from the combustion furnace 3 to a second flow rate smaller than the maximum flow rate, the internal combustion chamber 3 that has been heated to 800 ° C. or higher by the auxiliary combustion operation. Therefore, the running cost can be reduced by saving fuel required for the auxiliary combustion operation. In addition, at the start of the auxiliary combustion operation, the flow rate should be controlled in advance so as to correspond to the combustion exhaust in the next stage of the auxiliary combustion operation (the stage where dry distillation proceeds and a certain amount of combustible gas is expected). Thus, even when the amount of combustible gas generated varies transiently, the combustion exhaust from the combustion of the combustible gas is excessively retained in the combustion furnace 3 and shifts to a state where carbon monoxide is easily generated. Can be avoided.

  When the partial combustion of the waste A starts, the temperature in the dry distillation furnace 1 gradually increases, and when the temperature detected by the temperature sensor 32 reaches a predetermined temperature, the control device 14 performs the ignition without any abnormality. And the ignition device 15 is stopped. During ignition, the control valve 12 of the dry distillation oxygen supply path 9 is previously opened at a relatively small predetermined opening by a valve driver 13 controlled by the control device 14. As a result, the ignition of the waste A by the igniter 15 causes the carbonization in the carbonization furnace 1 and the oxygen (air) supply source 11 through the main oxygen supply path 10 and the dry distillation oxygen supply path 9. This is done using a small amount of oxygen fed to the furnace 1.

  When the partial combustion of the waste A starts in the lower layer of the waste A in the dry distillation furnace 1 by ignition, the upper layer of the waste A starts to dry by the combustion heat, and the combustible gas generated by the dry distillation. Is introduced into the burner section 18 of the combustion furnace 3 through the gas passage 2 connected to the carbonization furnace 1. After the ignition, the control device 14 gradually increases the opening degree of the control valve 12 provided in the dry distillation oxygen supply path 9 in a stepwise manner according to a predetermined program. As a result, oxygen is supplied to the lower layer portion of the waste A to a level necessary and sufficient for the continuous combustion, and the lower layer portion of the waste A is stabilized without expanding more than necessary, and the waste A The dry distillation of the upper layer will be carried out stably.

  When the combustible gas is introduced into the burner unit 18 of the combustion furnace 3, the control valve 23 of the combustion oxygen supply path 22 is opened at a predetermined opening degree in advance by a valve driver 24 controlled by the control device 14. ing. Therefore, the combustible gas introduced into the burner unit 18 is mixed with oxygen supplied from the combustion oxygen supply path 22 in the burner unit 18 and ignited by the combustion flame supplied from the combustion device 25. It burns with the fuel. When combustion of the combustible gas is started, generation of the combustible gas by the dry distillation is unstable, and the combustible gas is not stably supplied to the combustion furnace 3.

  Therefore, the control device 14 changes the combustion device 25 from high temperature combustion to low temperature combustion when the temperature T in the combustion furnace 3 detected by the temperature sensor 33 becomes a second temperature of 800 ° C. or higher, for example, 835 ° C. or higher. Even if the ratio of the combustion of the fuel by the combustion device 25 is reduced due to the change of the temperature T after switching, the temperature T in the combustion furnace 3 can be maintained at 830 ° C. or higher due to the increase in combustible gas. Determine whether or not.

  That is, after the combustion of the fuel is switched to the low temperature combustion, if the temperature T in the combustion furnace 3 becomes 835 ° C. or lower, the temperature T can still be maintained at 830 ° C. or higher by the combustion of the combustible gas. It is determined that the state is not reached, and the combustion device 25 is switched from low temperature combustion to high temperature combustion. When the temperature T in the combustion furnace 3 becomes 835 ° C. or higher, the combustion device 25 is switched from high temperature combustion to low temperature combustion again, and the combustible gas increases to maintain the temperature T at 830 ° C. or higher. Repeat the operation to determine whether it is possible.

As a result, the combustion of the fuel by the combustion device 25 is intermittently performed such as low temperature combustion when the temperature T in the combustion furnace 3 becomes 835 ° C. or higher, and high temperature combustion when the temperature T becomes 835 ° C. or lower. 3 changes in a zigzag shape as shown in FIG. If the temperature T in the combustion furnace 3 is maintained at 835 ° C. or higher even when the combustion of the fuel by the combustion device 25 is performed at a low temperature at time t ₃ , the control device 14 determines the combustible gas. Is increased to reach a state where the temperature T can be maintained at 830 ° C. or higher, and the combustion state of the combustion device 25 is switched to intermittently perform low-temperature combustion.

In synchronization with the switching of the combustion state of the combustion apparatus 25 at time t _3, the control device 14 that the degree of opening of the gate damper 26 is set changes from the intermediate opening OPmid the maximum opening degree OPmax (100% opening) by Thus, the discharge flow rate of the combustion exhaust discharged from the combustion furnace 3 is controlled from the second flow rate to the maximum flow rate.

  The maximum flow rate is predicted to be exhausted from the combustion furnace 3 when the temperature in the combustion furnace 3 is stably maintained by the combustion of only the combustible gas due to the further increase of the generation amount of the combustible gas. The flow rate is set based on combustion exhaust. In other words, the maximum flow rate is a design value in the dry distillation gasification incineration processing apparatus. That is, the diameter of the duct 26a is determined in accordance with the maximum flow rate based on the predicted combustion exhaust.

  In this way, even if the fuel combustion rate is reduced, the temperature in the combustion furnace 3 is maintained at 835 ° C. by the combustible gas (the stage in which the carbonization proceeds and a certain amount of combustible gas is expected to be generated) ), In view of the subsequent increase in the amount of combustible gas generated, the discharge flow rate of the combustion exhaust discharged from the combustion furnace 3 is set to the maximum flow rate, so that the dry distillation of the waste A progresses quickly and is flammable. Even when the amount of gas generated suddenly increased, the combustion exhaust due to the combustion of the combustible gas was excessively retained in the combustion furnace, and it was prevented from shifting to a state where carbon monoxide was likely to be generated. It can cope with combustion exhaust by combustion of combustible gas.

Next, after switching the combustion state of the combustion device 25 to intermittently perform low-temperature combustion at time t ₃ , the control device 14 detects the temperature in the combustion furnace 3 detected by the temperature sensor 33 due to an increase in combustible gas. When the temperature T becomes a stable temperature higher than the second temperature, for example, 860 ° C. or more, the low-temperature combustion of the fuel by the combustion device 25 is stopped, and the change of the temperature T after the stop causes the combustible gas to spontaneously It is determined whether combustion can be continued stably.

  That is, after the low-temperature combustion of the fuel is stopped, if the temperature T in the combustion furnace 3 becomes 860 ° C. or less, it is determined that the combustible gas cannot yet be combusted spontaneously, and the combustion device 25 Is re-ignited to resume low-temperature combustion of the fuel. If the temperature T in the combustion furnace 3 reaches 860 ° C. or higher, can the low-temperature combustion of the fuel by the combustion device 25 be stopped again, and the combustible gas can be spontaneously stabilized and continue to burn? Repeat the operation to determine whether or not.

As a result, the low-temperature combustion of the fuel by the combustion device 25 is intermittently performed such that the temperature T in the combustion furnace 3 is stopped when the temperature T becomes 860 ° C. or higher, and is restarted when the temperature T becomes 860 ° C. or lower. The temperature in 3 changes in a zigzag shape as shown in FIG. If the temperature T in the combustion furnace 3 is maintained at 860 ° C. or higher even when the low temperature combustion of the fuel by the combustion device 25 is stopped at time t ₄ , the control device 14 causes the combustible gas to be maintained. Determines that it has reached a state where it can spontaneously combust due to its own combustion heat, and terminates the low temperature combustion of the fuel by the combustion device 25. Thereafter, spontaneous combustion of only the combustible gas is performed, and the temperature T in the combustion furnace 3 detected by the temperature sensor 33 substantially indicates the combustion temperature of the combustible gas itself. .

  When spontaneous combustion of only the combustible gas is performed, the combustion temperature of the combustible gas itself detected by the temperature T in the combustion furnace 3 is maintained at a substantially constant temperature of 860 ° C. At this time, the control device 14 automatically controls the opening degree of the control valve 23 of the combustion oxygen supply passage 22 so that a sufficient amount of oxygen necessary for complete combustion of the combustible gas is supplied to the burner unit 18. To do. Specifically, in the control, when the combustion temperature T of the combustible gas in the combustion furnace 3 is lower than 860 ° C., the opening degree of the control valve 23 is reduced, and the amount of oxygen supplied to the burner unit 18 is reduced. Conversely, when the temperature T becomes higher than 860 ° C., the opening of the control valve 23 is increased and the amount of oxygen supplied to the burner unit 18 is increased.

  At the same time, the control device 14 automatically controls the opening degree of the control valve 12 according to the combustion temperature T of the combustible gas in the combustion furnace 3 detected by the temperature sensor 33, so that The amount of the combustible gas generated is adjusted so that the combustion temperature T of the combustible gas in the combustion furnace 3 is maintained at 850 ° C. substantially constant. Specifically, in the control, when the combustion temperature T of the combustible gas in the combustion furnace 3 becomes lower than 860 ° C., the opening degree of the control valve 12 is increased and the oxygen supply amount to the dry distillation furnace 1 is increased. The generation of the combustible gas by the dry distillation is promoted. On the other hand, when the combustion temperature T of the combustible gas in the combustion furnace 3 becomes higher than 860 ° C., the control valve 12 is opened to reduce the amount of oxygen supplied to the dry distillation furnace 1. The generation of the combustible gas due to the dry distillation is suppressed. Thereby, in the dry distillation furnace 1, combustion of the lower layer part of the waste A and dry distillation of the upper layer part proceed stably, and the temperature T in the combustion furnace 3 is maintained substantially constant at 860 ° C.

  As described above in detail, according to the dry distillation gasification incineration processing apparatus of this embodiment, the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace 3 during the warm-up operation is excellent in the combustion state of the fuel in the combustion furnace 3. Limit to the minimum possible. Thereby, it is possible to save time and fuel required for warming up while realizing clean exhaust.

  Further, in the auxiliary combustion operation following the warm-up operation, the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace 3 is increased stepwise in anticipation of the subsequent increase in the amount of combustible gas generated. As a result, the combustion state shifts to a state where carbon monoxide is likely to be generated due to an increase in combustible gas while suppressing a decrease in the temperature in the combustion furnace 3 heated to 800 ° C. or more by the warm-up operation. It can be avoided.

  In this embodiment, the cooling furnace 27 is connected to the combustion furnace 3 and the gate damper 26 is attached to the duct 26a on the outlet side of the cooling furnace 27. However, the installation position of the gate damper 26 is the same. It is not limited. That is, if it is downstream from the outlet of the combustion furnace 3 and upstream of the induction fan 31, it is attached to a duct 26 b between the cooling tower 28 and the bag filter 29 or a duct 26 c between the bag filter 29 and the induction fan 31. May be.

  When the outlet of the combustion furnace 3 is connected to a heat exchanger or the like through a duct instead of the cooling furnace 27, a duct or a heat exchanger between the combustion furnace 3 and the heat exchanger or the like is used. The gate damper 26 may be attached to the downstream duct.

  Furthermore, in the present embodiment, the gate damper 26 has been described as an example of the flow rate control means. However, the present invention is not limited thereto, and combustion exhaust exhausted from the combustion furnace 3 using various dampers and valves other than the gate damper. The discharge flow rate may be controlled.

The system block diagram which shows one Embodiment of the dry distillation gasification incineration processing apparatus of this invention. The graph which shows the time-dependent change of the combustion temperature in a combustion furnace, the opening degree of a gate damper, and the induction pressure by an induction fan.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Dry distillation furnace, 3 ... Combustion furnace, 12 ... Control valve (dry distillation oxygen supply means), 14 ... Control apparatus, 16 ... Fuel supply apparatus, 23 ... Control valve (combustion oxygen supply means), 25 ... Combustion apparatus (combustion means) ), 26... Gate damper (flow rate control means, pipe area adjustment means), 31 .. Induction fan (attraction means), 33... Temperature sensor (combustion furnace temperature detection means), A.

Claims (7)

A combustible gas for storing combustible gas and combusting a part of the waste material to dry-distill the remainder of the waste material with the heat of combustion to generate combustible gas, and combustible gas introduced from the combustible gas furnace , Combustion oxygen supply means for supplying oxygen required for combustion to the combustion furnace in accordance with the amount of combustible gas introduced into the combustion furnace, and combustion furnace for detecting the temperature in the combustion furnace A temperature detecting means, and the temperature of the combustion furnace detected by the combustion temperature detecting means after combustion of the combustible gas in the combustion furnace is maintained at a preset temperature. Dry distillation oxygen supply means for adjusting the oxygen supply amount to the combustion chamber, combustion means for burning fuel in the combustion furnace, flow rate control means for controlling the flow rate of exhaust gas from the combustion furnace, and combustion exhaust gas in the combustion furnace Carbonization gas with attracting means to attract An incinerator,
Prior to the ignition of the waste, the induction means induces the inside of the combustion furnace and the combustion means combusts the fuel, and the temperature in the combustion furnace is set at a first temperature at which dioxins can be thermally decomposed. In the warming-up operation in which the warming-up is performed as described above, the first flow rate control unit restricts the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace most within a range in which the amount of carbon monoxide generated in the combustion furnace is equal to or less than the threshold value. A dry distillation gasification incineration apparatus characterized by controlling the flow rate. In the carbonization incineration processing apparatus according to claim 1,
When the temperature in the combustion furnace becomes equal to or higher than the first temperature by the combustion means, the waste is ignited to start dry distillation, and the generated combustible gas is combusted together with the fuel in the combustion furnace. A dry distillation gas characterized in that, at the start of the auxiliary combustion operation to be performed, the discharge flow rate of the combustion exhaust discharged from the combustion furnace is controlled by the flow rate control means to a second flow rate that is larger than the first flow rate and smaller than the maximum flow rate. Incineration equipment. In the carbonization incineration processing apparatus according to claim 2,
The flow rate control means uses the increase in the amount of combustible gas generated as the second flow rate even if the temperature in the combustion furnace in the auxiliary combustion operation reduces the rate of combustion of the fuel by the combustion means. Carbon monoxide in the combustion furnace when the temperature of the combustion furnace is maintained at a second temperature that is equal to or higher than the first temperature and lower than a stable temperature at which the temperature of the combustion furnace is stably maintained by combustion of only the combustible gas The dry distillation gasification incineration processing apparatus is characterized in that the flow rate is controlled to be the most limited within a range in which the generation amount of the gas is equal to or less than the threshold value. In the carbonization incineration processing apparatus according to claim 2,
Even if the temperature in the combustion furnace in the auxiliary combustion operation decreases the rate of combustion of the fuel by the combustion means, the temperature is equal to or higher than the first temperature due to an increase in the generation amount of the combustible gas. When the combustion furnace temperature is maintained at the second temperature lower than the stable temperature at which the combustion furnace temperature is stably maintained, the exhaust flow rate of the combustion exhaust exhausted from the combustion furnace by the flow rate control means is maximized. A dry distillation gasification incineration apparatus characterized by controlling the flow rate. In the dry distillation gasification incineration processing apparatus according to any one of claims 1 to 4,
The flow rate control means includes a pipe area adjusting means that is provided in a pipe line on the outlet side of the combustion furnace and adjusts the area of the pipe line,
A dry distillation gasification incineration processing apparatus, wherein the discharge area flow rate of the combustion exhaust discharged from the combustion furnace is controlled by the pipe line area adjusting means adjusting the area of the pipe line. In the dry distillation gasification incineration processing apparatus according to any one of claims 1 to 5,
The attraction means changes a pressure for inducing combustion exhaust in the combustion furnace in accordance with an operation state, and is a dry distillation gasification incineration processing apparatus. A step of igniting the waste contained in the carbonization furnace to combust a part of the waste and subjecting the other part of the waste to carbonization by the heat of combustion; a combustible gas generated by the carbonization; And combusting the combustible gas in the combustion furnace with oxygen required for the combustion in accordance with the amount of combustible gas introduced into the combustion furnace. The combustible gas is supplied and combusted, and the amount of oxygen supplied to the dry distillation furnace is controlled according to the temperature change in the combustion furnace due to the combustion of the combustible gas in the combustion furnace, and generated by the dry distillation. In the incineration processing method of adjusting the amount of combustible gas and maintaining the temperature in the combustion furnace at a preset temperature,
Prior to the ignition of the waste, the inside of the combustion furnace is attracted and the fuel is combusted. A first step of controlling a discharge flow rate of combustion exhaust discharged from the combustion furnace to a minimum flow rate;
When the temperature in the combustion furnace becomes equal to or higher than the first temperature, the waste is ignited to start dry distillation, and the generated combustible gas is combusted together with the fuel in the combustion furnace. A second step of controlling a discharge flow rate of the combustion exhaust discharged from the combustion furnace at the start to an intermediate flow rate that is larger than the minimum flow rate and smaller than the maximum flow rate;
Even if the temperature in the combustion furnace in the auxiliary combustion operation decreases the rate of combustion of the fuel, the combustion temperature of the combustion furnace is higher than the first temperature due to an increase in the amount of combustible gas generated, and only by the combustion of the combustible gas. A third step of controlling a discharge flow rate of the combustion exhaust discharged from the combustion furnace to a maximum flow rate when the temperature of the combustion furnace is maintained at a second temperature lower than a stable temperature at which the combustion furnace is stably maintained; An incineration processing method, which is performed in order.

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