JP4413249B2 - Cremation furnace combustion control system and cremation furnace combustion control method - Google Patents

Description

  The present invention relates to a cremation furnace combustion control system and a cremation furnace combustion control method.

  In recent years, the crematorium has been developed as a modern, pollution-free facility that wipes out the traditional image. In particular, the cremation furnace, which is the main equipment, is required to have a performance that does not emit smoke and does not generate odors. Furthermore, the emission of dioxins is required to be less than a certain value, similar to a waste incinerator. .

  On the other hand, it is necessary for the cremation furnace to be incinerated so that the remains remain for picking up bones, and to be incinerated within the prescribed time regardless of the size of the remains, sub-funerals, and jars. A complicated operation different from normal incineration equipment is required, and failure is not allowed.

  The cremation furnace is a very unique combustion device that performs two processes in one furnace, the self-combustion process in the first half of the cremation and the direct incineration in the second half. In addition, the intermittent operation is unique.

  FIG. 1 is a schematic diagram illustrating a standard cremation process. In the figure, 1 is a cooling chamber, 2 is a main combustion furnace, 3 is a trolley inside the furnace, 4 is a gutter, 5 is a gantry, and 6 is a remains.

  Since cremation in Japan has a custom of picking up burned bones immediately after the cremation is over, cremation is carried out on a movable furnace carriage. The cremation process will be specifically described as follows.

(A) Place the rod 4 on the in-furnace carriage 3 in the cooling chamber 1.
(B) The in-furnace trolley 3 is placed in the main combustion furnace 2 of the cremation furnace, and the body is burned together with the firewood 4 and the auxiliary equipment to form burned bone.
(C) After the furnace truck 3 is cooled in the furnace to some extent, it is taken out from the main combustion furnace 2, further cooled in the cooling chamber 1, and then picked up in the picking chamber in front of the cooling chamber 1.

  As shown in FIG. 1, the operation of the cremation furnace is to carry out a process of rapid heating → incineration → cooling for each cremation, and most of the operation is performed only once or twice a day. Batch operation. One cremation takes about 1 hour to 1 and a half hours, and the time between cremation and cremation is 30 minutes to several hours.

  In addition, cremation has the following characteristics from the viewpoint of burning the body.

(1) From the standpoint of protecting the deceased's dignity, it is not preferable to apply mechanical force to the body from outside.

(2) In the first half of the cremation, there is a large amount of flammable substances such as spears, side funerals, and dead body fat, and after firing the burner due to the effect of ceramic fiber on the main combustion furnace wall, Abrupt combustion occurs, and a large amount of combustion gas is temporarily generated. Combustion at this time is mainly self-combustion, and the supply amount control of the combustion air and the furnace pressure control are important factors. At this stage, it is important not to make the combustion runaway. The point of cremation furnace control is determined by how this part is optimally performed.

(3) In the second half of the cremation, a relatively small amount of high moisture content non-combustible material centering on the abdomen of the corpse is burned with a burner flame. Combustion during this period is mainly direct incineration by the burner flame, and maintaining the high temperature and promptly renewing the combustion surface of the combusted material are important points.

  Therefore, advanced technology is required to operate the cremation furnace automatically and optimally.

  In the era when there was no automatic operation system, each device performed single-loop control for individual control factors. In this case, when trying to operate the furnace in an optimal state, especially in the first half of the cremation, Had to stick to the furnace. That is, it is necessary to monitor the combustion state and manually adjust the output of each burner.

  In addition, the furnace pressure control is always torn in preparation for the case of abnormal combustion because the burning rate increases too much when there are many combustibles such as collaterals or when the fat content of the corpse is high. It was necessary to make it negative. As a result, even when the burned material in the second half of the cremation decreases or even in the first half of the cremation, the heat generated when the calorific value of the burned material is relatively low cannot be fully utilized, and the main combustion furnace, Both the combustion furnaces were in a situation where the temperature was difficult to rise, and burners were burned using waste fuel to maintain the temperature.

  Furthermore, in the second half of the cremation, in response to a request to complete the cremation quickly, a technique was taken to promote combustion by applying mechanical force to the body with a metal rod called Derekki or moving it. As a result, of course, there are individual differences in the driving skills of the workers, and the skilled workers are those who are good at using the Derek stick and can complete the cremation quickly. In other words, the situation of “preserving the dignity of the corpse” or “improvement of the working environment” was far away.

  Several proposals have been made as an automatic operation method of a cremation furnace.

  In Patent Document 1, a measuring device for measuring the weight of the combustion object is provided in the main combustion chamber, and according to the weight and weight change of the combustion object before and during combustion based on the output signal from the measuring device, A combustion control method for a cremation furnace that automatically controls the output of a combustion burner disposed in a main combustion chamber is disclosed.

  Patent Document 2 includes a main combustion chamber having a main burner with fluid fuel following the front chamber, a recombustion chamber having a sub burner with fluid fuel from the main combustion chamber through a flue, and from the front chamber. A cremation cart on which a firewood is placed on a self-propelled carrier cart with a length over the main combustion chamber is slidable in the longitudinal direction by means of transport provided on the carrier cart, and the carrier cart is placed in the funeral hall. In the cremation furnace to be inserted from the front hall into the front chamber, the continuous support body on which the carrier cart is placed from the front chamber to the main combustion chamber is supported by the front load cell and the main load cell for detecting the load of the cremation cart, A cremation pattern control means for automatically starting the secondary burner in accordance with the detection signal of the previous load cell and regulating the fuel supply amount and operating time of the main burner, and detecting the main load cell in the cremation pattern control means And a correction means for correcting the cremation situation, and an environment detection means for detecting the situation in which the recombustion chamber is heated until it is suitable for combustion of unburned gas by a temperature sensor and a timer. A cremation furnace is disclosed that activates the main burner with the output and the output of the cremation pattern control means.

  Patent Document 3 discloses a time series of ideal combustion temperatures from ignition to extinction in a control device that controls the burner thermal power and the amount of exhaust from the furnace based on the output signal of the combustion temperature detection means provided in the combustion furnace. An ideal data storage unit for holding data, a sequence control means for controlling the burner's heating power from ignition to extinction to burn along the time series data of the combustion temperature, the current combustion temperature and the ideal combustion temperature Combustion in a furnace equipped with a displacement control means for controlling the time series data to increase the displacement if the current combustion temperature is higher, or decrease the displacement if the current combustion temperature is lower A control device is disclosed.

  In Patent Document 4, a furnace temperature sensor is disposed in a combustion chamber having a predetermined combustion burner and an air supply unit, and a control unit for the fuel supply amount and the air supply amount of the burner is provided. A combustion method for a cremation furnace is disclosed in which the fuel supply amount and air supply amount of the burner are controlled on the basis of the temperature change rate of the furnace temperature measured by a sensor.

Japanese Patent Publication No. 3-9365 Japanese Patent No. 3878247 Japanese Patent No. 3795554 JP-A-9-273722

  The combustion control method for the cremation furnace disclosed in the above-mentioned Patent Document 1 automatically controls the output of the combustion burner according to the weight and weight change of the combustion object. ) And the weight change alone, it is difficult to finely control the combustion until the exhaust gas standard is satisfied even though the combustion object can be incinerated in the main combustion chamber.

  In the cremation furnace disclosed in Patent Document 2, a cremation carriage with a firewood is placed in the front chamber by providing a cremation pattern control means for regulating the fuel supply amount and operation time of the main burner according to the detection signal of the previous load cell. At the time of insertion into the cremation body, it is possible to detect the load of the cremation body, by driving the cremation pattern control means according to the detection signal, it becomes possible to perform an appropriate cremation process according to each cremation body, Moreover, although it is described that the cremation pattern given previously can be corrected by the main load cell, the cremation process can be performed, but as in Patent Document 1, fine combustion control until the exhaust gas standard is satisfied is difficult. .

  In the combustion control device disclosed in Patent Document 3, a temperature sensor and a pressure sensor are arranged at the sampling port of the main combustion chamber, and based on outputs of both sensors, an ideal data storage unit, a sequence control unit, an exhaust amount Although the control means and the thermal power correction means are controlled, it is difficult to control the combustion to reduce the smoke and odor of exhaust gas and the dioxin concentration below the reference value only by the temperature and pressure at the outlet of the main combustion chamber. is there.

  In the combustion method disclosed in Patent Document 4, the fuel supply amount and air supply amount of the burner are controlled on the basis of the temperature change rate of the furnace temperature measured by the furnace temperature sensor. Fine combustion control until it is satisfied is difficult.

  Accordingly, the present invention provides a cremation furnace combustion control system and a cremation furnace combustion control method capable of easily performing cremation of a certain level or more without requiring proficiency and performing fine combustion control satisfying exhaust gas standards. The purpose is to provide.

In order to solve the above problems, the first configuration of the present invention is:
A main combustion furnace provided with a main combustion burner and a main combustion furnace secondary air amount damper for burning the firewood placed on the bogie and the remains, sub-funders, etc.
A reburning furnace installed in communication with the main combustion furnace and provided with a reburning burner and a reburning furnace secondary air amount damper;
A cooler for cooling the exhaust from the reburning furnace;
A furnace outlet damper provided at the outlet of the cooler;
An induction fan for inducing exhaust from the reburning furnace;
An exhaust pipe for exhausting the exhaust to the atmosphere;
A main combustion furnace thermometer for measuring the furnace temperature of the main combustion furnace;
A recombustion furnace thermometer for measuring the in-furnace temperature of the recombustion furnace;
A flue gas concentration meter and an oxygen concentration meter for measuring the flue gas concentration and the oxygen concentration in the exhaust gas, respectively;
While satisfying the condition that the flue gas concentration measured by the flue gas concentration meter is 0 and the oxygen concentration measured by the oximeter is not less than a predetermined value, the output of the main combustion burner is maximized quickly. If the main combustion furnace temperature is within the target temperature range in the latter half of the first half of the cremation, the main combustion furnace secondary air amount damper is opened for a predetermined time, and the main combustion furnace When the furnace temperature is higher than the target temperature range, the main combustion furnace secondary air amount damper is closed, and if the furnace temperature in the main combustion furnace falls within the target temperature range, the main combustion furnace secondary A combustion control system for a cremation furnace, comprising a main combustion furnace temperature control means for performing auxiliary control for performing an operation of opening an air amount damper for a certain period of time.
In the first configuration, the main combustion burner is controlled so that the combustion time becomes the fastest under the basic goal of keeping the flue gas concentration at 0 by the main control, and the temperature of the main combustion furnace increases. Therefore, temperature control by auxiliary control is performed so as not to heat until the shape of the remains remains.
In the above description, the “primary air amount” is not defined with respect to the “secondary air amount”. However, in the present invention, the “primary air amount” is mixed with the fuel of the main burner and the reburn burner. The amount of air (in the main combustion furnace) refers to the amount obtained by adding the amount of air leaked from the outside to this.

The second configuration of the present invention is based on the recombustion furnace temperature signal measured by the recombustion furnace thermometer or the recombustion furnace outlet thermometer provided at the outlet of the recombustion furnace in the first configuration. If the temperature of the combustion furnace does not reach the target temperature, the output of the reburning burner is increased. Conversely, when the temperature of the reburning furnace is excessively increased, first, the reburning burner is extinguished. The reburning furnace temperature control means for adjusting the opening degree of the reburning furnace secondary air amount damper to increase the reburning furnace secondary air blowing amount, and in the case where the reburning furnace secondary air blowing amount is still insufficient, It is provided.
In this second configuration, since the combustibles decrease as the cremation progresses, the amount of exhaust gas generated in the main combustion furnace also decreases accordingly. Is to be done economically.

According to a third configuration of the present invention, in the first or second configuration, the main combustion furnace has a secondary air port that floats a soot on the bogie inside the furnace to a predetermined height and blows secondary air into the soot. A plurality of these are provided on the side wall.
Since the soot placed on the in-furnace carriage is in close contact with the upper surface of the in-furnace carriage, it is difficult for oxygen to be supplied, and the temperature at the bottom of the soot is difficult to rise. Therefore, in this third configuration, a flame on the main combustion burner is provided by providing a plurality of secondary air ports on the side wall by floating the soot on the bogie inside the furnace at a predetermined height and blowing secondary air therethrough, and providing the flame retardant part with the flame of the main combustion burner. By wrapping with, promote the burning of the corpse.

According to a fourth configuration of the present invention, in the first to third configurations, the main combustion furnace secondary air fed into the main combustion furnace, the air fed into the main combustion burner, and the recombustion fed into the recombustion furnace A combustion blower for generating secondary air for the furnace and air fed into the reburning burner is provided, and an inverter is used to keep the air pressure in the header of the combustion blower constant, and the rotation speed of the combustion blower is A constant pressure control means for performing control is provided.
In this fourth configuration, oxygen, which is one of the three elements of combustion, that is, a method for freely adjusting the amount of air is provided with a combustion blower and an inverter is used to keep the air pressure at the header constant. Then, the rotational speed of the combustion blower is controlled. The air can be freely supplied by controlling the air adjusting damper of each line.

According to a fifth configuration of the present invention, in the first to fourth configurations, based on the pressure signal of the recombustion furnace, the rotational speed control of the induction blower and the control of the furnace pressure by the furnace pressure control damper are performed. A pressure control means is provided.
If the control of the furnace pressure is not successful, the combustion gas blows out from the furnace when the pulling is not sufficient, and the combustion gas travels to the lower part of the furnace truck, damaging the wheels of the furnace truck. On the other hand, when the pulling is too large, a large amount of external leak air enters the furnace, and the furnace temperature hardly rises. Therefore, in this fifth configuration, based on the pressure signal of the re-combustion furnace, a speed control of the induced draft machine, and more possible to control the furnace pressure by a furnace pressure control damper to control the furnace pressure, While preventing blowing out of combustion gas, the furnace temperature is raised efficiently.

According to a sixth configuration of the present invention, in the first to fifth configurations, the main combustion burner and the reburn burner are control dampers, and the gas amount and the air amount are controlled separately.
In the sixth configuration, the air-fuel ratio can be freely changed. As a result, the position of the highest temperature portion of the flame can be changed without moving the main combustion burner and the reburn burner, and the air It is also possible to blow only air.

The seventh configuration of the present invention is:
A main combustion furnace provided with a main combustion burner and a main combustion furnace secondary air amount damper for burning the firewood placed on the bogie and the remains, sub-funders, etc.
A reburning furnace installed in communication with the main combustion furnace and provided with a reburning burner and a reburning furnace secondary air amount damper;
A cooler for cooling the exhaust from the reburning furnace;
A furnace outlet damper provided at the outlet of the cooler;
An induction fan for inducing exhaust from the reburning furnace;
An exhaust pipe for exhausting the exhaust to the atmosphere;
A main combustion furnace thermometer for measuring the furnace temperature of the main combustion furnace;
A recombustion furnace thermometer for measuring the in-furnace temperature of the recombustion furnace;
A combustion control method for a cremation furnace comprising a flue gas concentration meter and an oxygen concentration meter that measure the flue gas concentration and the oxygen concentration in the exhaust gas, respectively,
While satisfying the condition that the flue gas concentration measured by the flue gas concentration meter is 0 and the oxygen concentration measured by the oximeter is not less than a predetermined value, the output of the main combustion burner is maximized quickly. If the main combustion furnace temperature is within the target temperature range in the latter half of the first half of the cremation, the main combustion furnace secondary air amount damper is opened for a predetermined time, and the main combustion furnace When the furnace temperature is higher than the target temperature range, the main combustion furnace secondary air amount damper is closed, and if the furnace temperature in the main combustion furnace falls within the target temperature range, the main combustion furnace secondary A combustion control method for a cremation furnace characterized by performing auxiliary control for executing an operation of opening an air amount damper for a certain period of time.
In the seventh configuration, the main combustion burner is controlled so that the combustion time becomes the fastest under the basic goal of keeping the flue gas concentration at 0 by the main control, and the temperature of the main combustion furnace increases. Therefore, temperature control by auxiliary control is performed so as not to heat until the shape of the remains remains.

According to an eighth configuration of the present invention, in the seventh configuration, based on the recombustion furnace temperature signal measured by the recombustion furnace thermometer or the recombustion furnace outlet thermometer provided at the outlet of the recombustion furnace, If the temperature of the combustion furnace does not reach the target temperature, the output of the reburning burner is increased. Conversely, when the temperature of the reburning furnace is excessively increased, first, the reburning burner is extinguished. The reburning furnace secondary air amount damper is adjusted to increase the opening amount of the reburning furnace secondary air, and if it is still insufficient, only air is supplied from the reburning burner.
In the eighth configuration, since the combustibles decrease as the cremation progresses, the amount of exhaust gas generated in the main combustion furnace also decreases accordingly. Is to be done economically.

A ninth configuration of the present invention is the seventh or eighth configuration, in which when the flue gas concentration is small from 0 and repeatedly jumps, the furnace pressure is made negative and the output of the main combustion burner is reduced. If the flue gas concentration still increases, the main combustion burner is immediately stopped and the furnace pressure is made negative.
In the ninth configuration, by making the furnace pressure negative, the leakage air of the main combustion furnace is increased and combustion air is supplied, thereby eliminating incomplete combustion. Further, by reducing or eliminating the output of the main combustion burner to reduce the amount of secondary air in the main combustion furnace, smoke can be stopped almost certainly.

According to a tenth configuration of the present invention, in the seventh to ninth configurations, the oxygen concentration change rate in the main combustion furnace is calculated, and when this exceeds a certain level, the main combustion burner is extinguished. It is characterized by.
In the tenth configuration, it is possible to perform more optimal combustion by starting the control before smoking.

According to an eleventh configuration of the present invention, in the seventh to tenth configurations, when the temperature of the main combustion furnace is higher than a certain temperature, the main combustion furnace secondary air is blown at a predetermined blowing timing, It is characterized by being carried out in quantity (time).
The eleventh configuration is intended for combustion promotion control of the flame retardant part of the corpse. When the main combustion furnace temperature is low, the main combustion furnace secondary air is blown so that the main combustion furnace temperature does not decrease. Without this, the combustion is promoted by blowing secondary air when the temperature of the main combustion furnace is higher than a certain temperature.

  According to the present invention, the combustion control system and the cremation of the cremation furnace which can easily perform cremation of a certain level or more and perform fine combustion control satisfying the exhaust gas standard without requiring mastery by automation of combustion. A furnace combustion control method is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In order to perform automatic operation efficiently, it is necessary to make the furnace suitable for computer control while maintaining the performance of each equipment of the furnace. For this purpose, various ideas not available in other cremation furnaces are given below.

FIG. 2 shows a configuration of a current general cremation furnace combustion control system.
In FIG. 2, 1, 1 'is a cooling chamber, 2, 2' is a main combustion furnace, 7, 7 'is a recombustion furnace, 8, 8' is a cooler, 9, 9 'is a furnace outlet damper, and 10 is a bug. A filter, 11 is a catalyst, 12 is an induction blower, and 13 is an exhaust pipe. In this cremation furnace combustion control system, the cooling chambers 1, 1 'to the furnace outlet dampers 9, 9' are provided with two systems, and the common bag filter 10 to the exhaust pipe 13 are provided. Three or more systems may be used.

  In the present embodiment, the cremation furnace is provided with the recombustion furnaces 7 and 7 ', the bag filter 10, the dioxin decomposition catalyst 11 and the like in order to prevent the emission of bad odors and dioxins. The design and operation of the furnace 7,7 'is very important. The reburning furnace 7, 7 'is the center of pollution control equipment in the cremation furnace, and the quality of the reburning furnace 7, 7' greatly affects the quality of the exhaust gas, resulting in a bug filter. This is because it affects the lifetime of the catalyst 10 and the lifetime of the catalyst 11 of the catalyst tower and affects the quality of the fly ash collected by the bag filter 10.

  The main combustion furnaces 2 and 2 'are responsible for the combustion of the combusted material, and are devised to cope with the first half of the cremation and the second half of the cremation. Secondary air inlets are provided at several locations on both sides on the side wall of about 12 cm above the in-furnace carriage. FIG. 3 shows the situation in the main combustion furnace in (a) the first half of cremation and (b) the second half of cremation.

  Immediately before the cremation ignition, as shown in FIG. 3A, the firewood 4 occupies about 80% of the volume of the main combustion furnace 2, and after ignition, the volume of the burned material gradually decreases. In this case, the insufficient combustion air is supplemented by the leaked air that enters the furnace through the space between the in-furnace carriage 3 and the side wall and the secondary air. If there are many collaterals in 柩 4 or if the body is high in fat, excessive use of secondary air will cause excessive combustion and control the amount of secondary air so that combustion does not run away It is necessary. The amount of leaked air is inversely proportional to the furnace pressure, but the main combustion furnace 2 must always be kept at a negative pressure so that high-temperature combustion gas does not enter the lower part of the furnace carriage 3, so it always leaks into the main combustion furnace. Air has been introduced.

  In the second half of the cremation, as shown in FIG. 3 (b), a so-called flame-retardant portion having a large amount of moisture centered on the abdomen of the body is incinerated by the flame of the main burner 14. The surface of the flame retardant part is carbonized by the heat of the flame of the main combustion burner 14 and is covered with a carbon film. In such a state, since the thermal conductivity of the carbon covering the outside is small and the diffusion of oxygen is blocked by the carbon coating, it becomes a more difficult situation for combustion. The key to promoting the combustion of the flame retardant is to burn the carbon film on the surface well.

for that purpose,
(1) Efficient supply of heat to raise the temperature of the flame retardant part,
(2) Efficient supply of air (oxygen) for flame retardant combustion
is required.
In (1), not to mention the'll be well supplied moisture evaporation heat, total surface carbon efficiently 1000 for combustion ℃ high temperature above the holding of required (air pollution National Council ed: Air (See Contamination Handbook (3), Combustion, Corona (1973)).
In order to realize this, the frame 5 is used to float about 10 cm from the in-furnace carriage 3, and the flame retardant part of the corpse B is encased in the flame of the main combustion burner 14. Moreover, in order to implement | achieve (2), high-speed air is blown toward the flame-retardant part of the corpse B from the secondary air port of a furnace wall.

  The amount of exhaust gas discharged from the main combustion furnace 2 is not uniform, particularly in the first half of the cremation, and is discharged in an incompletely burned state. In order to completely burn this, a recombustion furnace 7 is installed following the main combustion furnace 2 as shown in FIG. The reburning furnace 7 is provided with a reburning burner 15 for raising the temperature and maintaining the temperature, and a secondary air inlet 16 for maintaining the oxygen concentration is provided at the lower part of the reburning burner 15. The recombustion furnace 7 requires good mixing properties and a sufficient gas residence time. As shown in FIGS. 4B and 4C, suitable throttles 17 and 18 are provided in the furnace. By this, the mixing property of combustion gas and secondary air is ensured. These mixing characteristics are based on the research by Kenji Fujiwara et al. “Development of a garbage combustion model for a batch incinerator” (Kenfuji Fujiwara, Junji Suzuki, Nobuo Takeda, Masateru Takaoka, Masaji Eguchi: Development of a garbage combustion model for a batch incinerator. , The journal “EICA”, Vol. 7, No. 2, 93-96 (2002)). The capacity of the recombustion furnace 7 is set such that the residence time of the combustion gas is secured for 2 seconds or more with respect to the maximum exhaust gas amount. Since the recombustion furnace 7 is installed following the main combustion furnace 2, the furnace pressure controllability of the main combustion furnace 2 depends on the response characteristics of the recombustion furnace 7 with respect to fluctuations in the internal pressure of the furnace. When the pressure loss of the recombustion furnace 7 is large, the response characteristics are also lowered. Therefore, a structure with a relatively small pressure loss is maintained while maintaining the mixing characteristics, and a structure as shown in FIG. 4 is adopted.

A system that supplies oxygen, that is, air, which is one of the three elements of combustion, is an important factor in burning an object.
As a method of adjusting the amount of air freely, as shown in FIG. 5, a system using a combustion blower 20 and control dampers 21 a to 21 d is constructed, and an inverter 23 is used to make the air pressure in the header 22 constant. The rotational speed control of the combustion blower 20 is performed. By measuring the header pressure of the blower 20 for combustion with a pressure gauge 24 provided in the header 22 and controlling the control dampers 21a to 21d of each line with a regulator 25, the air for the main combustion burner and the secondary for the main combustion furnace Air, reburn burner air, and reburn furnace secondary air can be freely supplied.

Control of the furnace pressure is extremely important for the furnace, and it is no exaggeration to say that the quality of the furnace pressure determines the performance of the furnace.
If the pressure inside the furnace is not well controlled (1) When pulling is not enough • Combustion gas blows out of the furnace.
-Combustion gas will travel to the bottom of the furnace truck and damage the wheels of the furnace truck.
(2) When the pull is too large ・ A large amount of external leak air enters the furnace and the furnace temperature is unlikely to rise.
In the case of (2), the fuel consumption for maintaining the furnace temperature increases, resulting in an increase in the amount of exhaust gas, which is not preferable from the viewpoint of energy saving.
As shown in FIG. 6, the furnace pressure is controlled by a furnace outlet damper 9, 9 ′ and an induction fan 12. In this method, a pressure signal of each recombustion furnace 7, 7 ′ is sent to the regulator 26, and the internal pressure of the furnace is controlled by controlling the rotational speed of the induction blower 12 and the furnace outlet dampers 9, 9 ′.

  As shown in FIG. 7, the burners (the main combustion burner 14 and the reburning burner 15) have a system in which the amount of gas and the amount of air are separately controlled by a regulator 28 using control dampers 29 a and 29 b. As a result, the air-fuel ratio of the main burner 14 and the reburn burner 15 can be freely changed. As a result, the position of the highest temperature portion of the flame can be changed without moving the burners 14 and 15. . It is also possible to blow only air.

  FIG. 8 shows the configuration of a control system related to combustion. The control computer 30 has six measurement signal inputs and six operation signal outputs. In the present embodiment, the measurement signals are the main combustion furnace thermometer 31, the furnace pressure gauge 32, the recombustion furnace thermometer 33, the recombustion furnace outlet thermometer 34, the oxygen concentration meter 35, and the flue gas concentration meter 36. The signals are the main combustion furnace secondary air quantity damper 37, the main combustion furnace burner output 38, the recombustion furnace secondary air quantity damper 39, the recombustion furnace burner output 40, the furnace outlet damper 41, and the induction fan rotational speed 42. As an interface with the operation side, an operation panel touch panel 43 such as a liquid crystal display is adopted so that each data can be displayed and the operation state of each device can be displayed, and each device can be manually operated. .

<Control configuration>
The configuration of the control is as shown in FIG. 9, and the main control is accompanied by six sub-controls, and is linked to each other through empirical control. The sub-controls of this embodiment are main combustion furnace temperature control, recombustion furnace temperature control, furnace pressure control, recombustion furnace oxygen concentration control, flue gas concentration control, and combustion acceleration control.

(1) Main control Main control is that the original purpose of the cremation furnace is to incinerate the body and quickly burn it, so the value of the flue gas concentration meter 36 is kept at 0 and the oxygen concentration is 6%. While maintaining the above (at least about 3% at the beginning of cremation), the output of the main burner 14 is maximized quickly.

(2) Main Combustion Furnace Temperature Control As shown in FIG. 10, the main combustion furnace temperature control is performed by fetching the signal from the main combustion furnace thermometer 31 into the control computer 30 to output the main combustion burner 14 and the main combustion. Although the amount of secondary air in the furnace is changed, the main operation is the output of the main combustion burner 14. That is, if the furnace temperature is low, the output of the main combustion burner 14 is increased, and if the furnace temperature is high, the output of the main combustion burner 14 is decreased. However, in this control method, in the first half of the cremation, a large amount of combustibles are present in the main combustion furnace 2, so that the main combustion burner 14 is kept to a minimum or extinguished state. The operation of the secondary air amount is important. When the main combustion furnace secondary air is introduced in the first half of the cremation, the temperature of the main combustion furnace 2 generally tends to rise, but in actuality, the calorific value of the combusted material and the timing of the main combustion furnace secondary air introduction Depending on the amount, it may descend. At this point, it must be absolutely avoided that the combustion runaway and become completely untouched. This is because it is a corpse that is burning, and it is not possible to take measures such as adding water to slow down the burning. As a solution, control based on empirical rules is added, and main combustion furnace temperature control is performed within a target temperature range (approximately 800 ° C. to 1100 ° C.). Here, the control logic is configured based on an empirical rule that “if the temperature rises when the secondary air is blown, the calorific value of the combusted material is high, and if it falls, the calorific value is low”. . That is, first, if the temperature condition is satisfied in the latter half of the first half of the cremation, the secondary air amount damper is opened for a certain time by X%. At this time, if it is within the range of the target temperature, the target operation is repeated, and if not, this operation is stopped. Here, the time, temperature condition, and target temperature are values determined by experience, and when the calorific value of the combusted material is large, the secondary output is in the minimum output of the main combustion burner 14 or in the fire extinguishing state. Good combustion can be performed only with air.
Of course, when the calorific value of the combusted material is small, the output of the main combustion burner 14 is increased, and the control for maintaining the combustion works.

(3) Recombustion furnace temperature control FIG. 11 shows a recombustion furnace temperature control system. The temperature control of the reburning furnace 7 is mainly performed by taking the signal of the reburning furnace outlet thermometer 34 or the reburning furnace thermometer 33 into the control computer 30 and changing the output of the reburning burner 15. If the temperature of the reburning furnace 7 does not reach the target temperature, the output of the reburning burner 15 is increased. Conversely, when the temperature of the reburning furnace 7 rises too much, first, the reburning burner 15 is extinguished. For example, the blowing amount of the recombustion furnace secondary air is increased, and if it is still insufficient, only air is supplied from the reburning burner 15. The amount of secondary air in the reburning furnace and the amount of air from the reburning burner 15 can be freely controlled by the damper 21a with a control motor. Here, empirical rules are used for the timing of extinguishing the reburning burner 15 and the usage of the two thermometers 33 and 34 installed in the reburning furnace 7.

  In cremation, since the amount of combustibles decreases, the amount of exhaust gas also decreases accordingly, so it is not possible to use a reburning furnace designed for the maximum gas amount from the beginning to the end in the same state. It is an economy.

Therefore, the following control is performed.
(A) First half of cremation-A recombustion furnace outlet thermometer 34 installed at the upper stage of the recombustion furnace 7 is used as a thermometer for measuring the temperature representative of the recombustion furnace.
-Set the reburning burner 15 to an ignition state.

(B) The second half of the cremation-As the thermometer for measuring the temperature representative of the reburning furnace 7, a reburning furnace thermometer 33 installed in the middle stage of the reburning furnace 7 is used.
-Extinguish the reburn burner 15.
The problem here is the determination of the first half and the second half of the cremation, and rules of thumb are used for this judgment. Determine whether the main combustion furnace is incineration centered on the main combustion burner 14 by the cremation time, main combustion burner output, main combustion furnace secondary air amount, and main combustion furnace temperature change rate. And the control of (b) is performed. Judgment standard values were all determined by empirical rules. This improvement has reduced fuel consumption.

(4) Furnace pressure control In this cremation system, as shown in FIG. 12, since one induction blower 12 is provided for two cremation furnaces C and C ′, two cremation furnaces C and C are provided. 'Control computers 30 and 30' operate the induction fan 12 in cooperation with each other to control the pressure in each furnace. Of the two control computers 30 and 30 ′, one has the right to operate the induction fan 12. The two control computers 30 and 30 ′ communicate with each other to share information.

  The control method targets the higher one of the two cremation furnace internal pressures, for example, the cremation furnace C, and controls the induction blower 12 so that the set furnace pressure is maintained. If it carries out like this, a negative pressure will become large in the other cremation furnace C ', and will be in what is called an excessive pulling state. By closing the furnace outlet damper 9 'of the other cremation furnace C' until a predetermined pressure is reached, the set pressure is obtained. As shown in FIG. 13, the control computers 30 and 30 ′ are coupled to each other and can switch the operation right of the common part D (the induction fan 12), and one of the control computers is down. However, it is a duplex system in which the control can be complemented by the other control computer.

  The furnace pressure control is: “In the first half of the cremation, a large amount of combustion gas is generated abruptly, so it is better to make the furnace pressure slightly negative, and in the second half the main combustion furnace temperature is kept high with less fuel. In addition, it is better to reduce the negative pressure based on an empirical rule. Specifically, for example, “the pressure Y1 is set from the main burner ignition to the soot ignition confirmation”, and “the pressure Y2 is set from the soot ignition confirmation to less than Xi minutes”. The target value is set to 9 levels and changed according to the cremation process. Here, the values of Xi and Yi are values determined by empirical rules. This method also helps to reduce fuel consumption.

(5) Smoke concentration control This control system is shown in FIG. The flue gas density is a value indicating the dust density as “light transmittance density (% OPACITY)” by installing a projector and a light receiver facing the flue, calculating the attenuation of the measurement light. Control of flue gas concentration was the most important control that became the center of combustion control until an oximeter was installed in the reburning furnace. In the first place, an increase in dust concentration means that combustion gas is generated exceeding the processing capacity of the reburning furnace under the condition that the reburning furnace control system is functioning normally. In general, there are the following methods for reducing the dust concentration.

(A) The furnace pressure is used as a key. Leakage air in the main combustion furnace 2 increases and combustion air is supplied, so that incomplete combustion is eliminated.
(B) Reduce or turn off the output of the main burner 14. Reduce the amount of secondary air in the main combustion furnace.

  This control is based on heuristics. When the flue gas disappears in the stage (a), the amount of combustion gas is considered not to be so large with respect to the reburning furnace capacity, whereas in the stage (b), only the main burner 14 is turned off. If the flue gas disappears, it means that the combustion gas greatly exceeds the reburning furnace capacity. Accordingly, when the needle of the flue gas concentration meter 36 repeatedly makes a small jump from 0, the pressure in the furnace becomes negative and the output of the main burner 14 is lowered. If the flue gas concentration meter still appears to rise, stop the main combustion burner 14 immediately and make the furnace pressure negative. At this stage, smoke can be prevented almost certainly. However, this smoke concentration control is a so-called follow-up control because control is applied only after smoke is detected.

(6) Oxygen Concentration Control As shown in FIG. 15, the oxygen concentration at the outlet of the reburning furnace 7 is controlled by the output of the reburning burner 15 and the amount of secondary air in the reburning furnace. The target value of oxygen concentration is usually 6% and about 3% in the first half of the cremation. When the oxygen concentration does not reach the target value only by the reburning furnace secondary air amount, the reburning burner 15 is stopped and only air is blown from the reburning burner 15. Since there is a clear correlation between the oxygen concentration and the flue gas concentration, it can be operated with empirical rules based on the furnace conditions. Basically, if the oxygen concentration drops below 1%, it will surely smoke. Therefore, by using this empirical rule, the main combustion burner 14 and the main combustion furnace secondary air amount can be operated in the same manner as in the smoke concentration control. In addition, the exhaust gas concentration control is a follow-up control, that is, the control is performed after the exhaust gas is emitted, but it is possible to start the control before the smoke is emitted and to perform more optimal combustion as a rule of thumb. . In general, when the smoke is likely to be emitted, the oxygen concentration change rate is calculated from the phenomenon that the oxygen concentration rapidly decreases, and when this exceeds a certain level, the main burner 14 is controlled to be extinguished. Here, the point at which the value of the change rate changes is an empirical value. By introducing this control, it became possible to stop smoke almost certainly. Therefore, if the oxygen concentration control is performed, the smoke concentration control becomes a secondary control. Therefore, at present, smoke concentration control is positioned as a backup for oxygen concentration control.

(7) Combustion Promotion Control FIG. 16 shows a combustion promotion control system. In the description of the main combustion furnace 2, the promotion of combustion of the incombustible part of the corpse B in the second half of the cremation was described, but the method of blowing the main combustion furnace secondary air is an important point. That is, the main combustion furnace temperature condition, the blowing timing, and the blowing amount. These are determined based on empirical rules and set in advance in the control computer 30 based on the main combustion furnace temperature measured by the main combustion furnace thermometer 31. Regarding temperature conditions, secondary air was blown only when the temperature was higher than a certain temperature. This is because if the main combustion furnace temperature is low, the combustion promoting effect is small, and the main combustion furnace temperature is lowered, and wasteful fuel is used for temperature rise. Both the blowing timing and the blowing amount (time) are determined based on empirical rules.

<Control result>
FIG. 17 to FIG. 20 show control results of furnace pressure, temperature (main combustion furnace, recombustion furnace), oxygen concentration, flue gas concentration, and carbon monoxide concentration by an automatic combustion system in actual operation. It can be seen that the pressure in the furnace almost falls within the range of −30 Pa to −10 Pa, and the magnitude of the negative pressure decreases as the cremation progresses. Next, the main combustion furnace and recombustion furnace temperatures also maintain the required temperature range. In addition, the oxygen concentration keeps 3% in the first half of the cremation and 6% or more in the second half. The generation of carbon monoxide is extremely small. A small amount of cremation was generated at the beginning of the cremation, because kerosene was used as fuel, and carbon monoxide was generated during ignition. In addition, this furnace does not perform manual operation at all and is automatically operated over the whole. Also, no derecking operation is performed. From the above, this automatic combustion system can be said to be an extremely effective cremation furnace combustion system.

<Summary>
Incorporating heuristics combustion control system of cremation furnace, with improved stability and quick response of the control. The effects of the present embodiment are summarized as follows.

1) Cremation is self-combustion in the first half due to the presence of a large amount of combustibles in the main combustion furnace. In the second half, the abdomen of the dead body is incinerated with the heat of the main combustion burner. This is a unique combustion process that uses two different combustion methods. In order to efficiently perform this process, a secondary air inlet is provided on the furnace wall of the main combustion furnace, and a stand is provided on the carriage in the furnace.

2) Exhaust gas introduced from the main combustion furnace into the recombustion furnace changes quantitatively. To operate this efficiently, the furnace type of the recombustion furnace is a cylindrical saddle and the inside is throttled. Mixing of exhaust gas was improved by providing two stages. In addition, oxygen concentration control was adopted. Furthermore, the furnace pressure control response was improved.

3) The system was configured so that burner output control, combustion air supply amount control, and furnace pressure control could be performed by a control computer.

4) The combustion control program was created by incorporating empirical rules in addition to the combustion theory. As a result, even in the intermittent operation, stable combustion is performed in the main combustion furnace, and stable combustion is also performed in the recombustion furnace in combination with improvement in the rapid response of the furnace pressure control.
As a result, a cremation furnace with stable combustion was completed.

  The present invention is suitable as a combustion control system for a cremation furnace and a combustion control method for the cremation furnace that can easily perform cremation of a certain level or more by anyone and can perform fine combustion control satisfying exhaust gas standards by automating combustion. Can be used.

It is explanatory drawing which shows the current standard cremation process. It is a block diagram which shows the combustion control system of the present general cremation furnace. It is the schematic which shows the condition in the main combustion furnace in embodiment of this invention. It is the schematic which shows the structure of the recombustion furnace in embodiment of this invention. It is the schematic which shows the air supply system in embodiment of this invention. It is a block diagram which shows the furnace pressure control system in embodiment of this invention. It is a block diagram which shows the control system of the burner in embodiment of this invention. It is a block diagram which shows the control system in embodiment of this invention. It is a block diagram which shows the structure of control in embodiment of this invention. It is the schematic which shows the main combustion furnace temperature control system in embodiment of this invention. It is the schematic which shows the recombustion furnace temperature control system in embodiment of this invention. It is a block diagram which shows the furnace pressure control system in embodiment of this invention. It is a block diagram which shows the computer backup system in embodiment of this invention. It is a block diagram which shows the smoke concentration control system in embodiment of this invention. It is a block diagram which shows the oxygen concentration control system in embodiment of this invention. It is the schematic which shows the combustion promotion control system in embodiment of this invention. It is a graph which shows the fluctuation | variation of the furnace pressure in embodiment of this invention. It is a graph which shows the furnace temperature change in embodiment of this invention. It is a graph which shows the oxygen concentration and smoke concentration change in embodiment of this invention. It is a graph which shows carbon monoxide density | concentration change in embodiment of this invention.

Explanation of symbols

1, 1 'Cooling chamber 2, 2' Main combustion furnace 3 In-furnace cart 4 柩 5 Mount 6 Remains 7, 7 'Reburning furnace 8, 8' Cooler 9, 9 'Furnace outlet damper 10 Bag filter 11 Catalyst 12 Attraction Blower 13 Exhaust tube 14 Main combustion burner 15 Reburn burner 16 Secondary air blow-in port 17, 18 Restriction 20 Combustion blower 21a to 21d Control damper 22 Header 23 Inverter 24 Pressure gauge 25, 26 Controller 27 Inverter 28 Controller 29a, 29b Control damper 30 Control computer 31 Main combustion furnace thermometer 32 Furnace pressure gauge 33 Recombustion furnace thermometer 34 Recombustion furnace outlet thermometer 35 Oxygen concentration meter 36 Flue gas concentration meter 37 Main combustion furnace secondary air quantity damper 38 Main Combustion furnace burner output 39 Recombustion furnace secondary air quantity damper 40 Recombustion furnace burner output 41 Furnace outlet damper 42 Fan speed 43 Operation panel touch panel B Body C, C 'Cremation furnace D Common part

Claims (11)

A main combustion furnace provided with a main combustion burner and a main combustion furnace secondary air amount damper for burning the firewood placed on the bogie and the remains, sub-funders, etc.
A reburning furnace installed in communication with the main combustion furnace and provided with a reburning burner and a reburning furnace secondary air amount damper;
A cooler for cooling the exhaust from the reburning furnace;
A furnace outlet damper provided at the outlet of the cooler;
An induction fan for inducing exhaust from the reburning furnace;
An exhaust pipe for exhausting the exhaust to the atmosphere;
A main combustion furnace thermometer for measuring the furnace temperature of the main combustion furnace;
A recombustion furnace thermometer for measuring the in-furnace temperature of the recombustion furnace;
A flue gas concentration meter and an oxygen concentration meter for measuring the flue gas concentration and the oxygen concentration in the exhaust gas, respectively;
While satisfying the condition that the flue gas concentration measured by the flue gas concentration meter is 0 and the oxygen concentration measured by the oximeter is not less than a predetermined value, the output of the main combustion burner is maximized quickly. If the main combustion furnace temperature is within the target temperature range in the latter half of the first half of the cremation, the main combustion furnace secondary air amount damper is opened for a predetermined time, and the main combustion furnace When the furnace temperature is higher than the target temperature range, the main combustion furnace secondary air amount damper is closed, and if the furnace temperature in the main combustion furnace falls within the target temperature range, the main combustion furnace secondary A combustion control system for a cremation furnace, comprising a main combustion furnace temperature control means for performing auxiliary control for performing an operation of opening an air amount damper for a predetermined time.   Based on the recombustion furnace temperature signal measured by the recombustion furnace thermometer or the recombustion furnace outlet thermometer provided at the outlet of the recombustion furnace, if the temperature of the recombustion furnace does not reach the target temperature, the recombustion burner When the temperature of the recombustion furnace rises too much, the fire of the reburning burner is extinguished first. 2. The cremation furnace according to claim 1, further comprising: a recombustion furnace temperature control means for increasing the amount of secondary air blown into the recombustion furnace and, if still insufficient, supplying only air from the reburning burner. Combustion control system.   3. The main combustion furnace according to claim 1 or 2, wherein a plurality of secondary air ports are provided in the side wall for floating the soot on the bogie in the furnace to a predetermined height and blowing secondary air therethrough. The cremation furnace combustion control system described.   Combustion that generates secondary air for main combustion furnace to be sent to the main combustion furnace, air to be sent to the main combustion burner, secondary air for recombustion furnace to be sent to the reburning furnace, and air to be sent to the reburning burner 2. A pressure constant control means for controlling the number of revolutions of the combustion blower using an inverter is provided in order to provide a blower for use and to make the air pressure in the header of the combustion blower constant. The combustion control system for a cremation furnace according to any one of items 3 to 3. 5. The pressure control means for controlling the rotational speed of the induction blower and the pressure in the furnace by a furnace pressure control damper based on a signal of the pressure of the recombustion furnace is provided. A combustion control system for a cremation furnace according to any one of the above sections.   The combustion control system for a cremation furnace according to any one of claims 1 to 5, wherein the main burner and the reburn burner are controlled dampers so that the gas amount and the air amount are separately controlled. A main combustion furnace provided with a main combustion burner and a main combustion furnace secondary air amount damper for burning the firewood placed on the bogie and the remains, sub-funders, etc.
A reburning furnace installed in communication with the main combustion furnace and provided with a reburning burner and a reburning furnace secondary air amount damper;
A cooler for cooling the exhaust from the reburning furnace;
A furnace outlet damper provided at the outlet of the cooler;
An induction fan for inducing exhaust from the reburning furnace;
An exhaust pipe for exhausting the exhaust to the atmosphere;
A main combustion furnace thermometer for measuring the furnace temperature of the main combustion furnace;
A recombustion furnace thermometer for measuring the in-furnace temperature of the recombustion furnace;
A combustion control method for a cremation furnace comprising a flue gas concentration meter and an oxygen concentration meter that measure the flue gas concentration and the oxygen concentration in the exhaust gas, respectively,
While satisfying the condition that the flue gas concentration measured by the flue gas concentration meter is 0 and the oxygen concentration measured by the oximeter is not less than a predetermined value, the output of the main combustion burner is maximized quickly. If the main combustion furnace temperature is within the target temperature range in the latter half of the first half of the cremation, the main combustion furnace secondary air amount damper is opened for a predetermined time, and the main combustion furnace When the furnace temperature is higher than the target temperature range, the main combustion furnace secondary air amount damper is closed, and if the furnace temperature in the main combustion furnace falls within the target temperature range, the main combustion furnace secondary A combustion control method for a cremation furnace characterized by performing auxiliary control for performing an operation of opening an air amount damper for a certain period of time.   Based on the recombustion furnace temperature signal measured by the recombustion furnace thermometer or the recombustion furnace outlet thermometer provided at the outlet of the recombustion furnace, if the temperature of the recombustion furnace does not reach the target temperature, the recombustion burner When the temperature of the recombustion furnace rises too much, the fire of the reburning burner is extinguished first. The combustion control method for a cremation furnace according to claim 7, wherein the amount of secondary air blown into the reburning furnace is increased and only air is supplied from the reburning burner when the amount is still insufficient.   When the flue gas concentration is low from 0 and the jump is repeated, the furnace pressure is reduced to a negative pressure, the output of the main burner is lowered, and if the flue gas concentration still increases, the main burner burner is immediately turned off. The combustion control method for a cremation furnace according to claim 7 or 8, wherein the combustion is stopped and the pressure in the furnace is set to a negative pressure.   10. The cremation according to claim 7, wherein a rate of change of oxygen concentration in the main combustion furnace is calculated, and control is performed to extinguish the main combustion burner when the oxygen concentration change rate exceeds a certain value. Furnace combustion control method.   11. The main combustion furnace secondary air is blown at a predetermined blowing timing and a blowing amount (time) when the temperature of the main combustion furnace is higher than a certain temperature. A combustion control method for a cremation furnace according to any one of the above items.

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