CN114568031A - Waste combustion device and waste combustion method - Google Patents

Abstract

The waste combustion device is provided with: a hopper into which waste is fed; a feeder that supplies the waste fed into the hopper; a charging machine disposed in a combustion chamber for burning waste; a boiler for generating steam by using combustion heat generated in the combustion chamber; a water content meter for measuring the water content of the waste; and a control device which includes a heat generation amount change determination unit that determines a change in the amount of heat generated by the waste based on the amount of moisture of the waste measured by the moisture meter, an adjustment value determination unit that determines an adjustment value of the operation amount of the feeder based on a result of the change in the amount of heat generated, and an operation amount control unit that controls the feeder based on the adjustment value of the operation amount of the feeder determined by the adjustment value determination unit.

Description

Waste combustion device and waste combustion method

Technical Field

The present disclosure relates to a waste combustion apparatus and a waste combustion method.

The present application claims priority based on japanese patent application No. 2019-192672, filed on 23/10/2019, and the contents thereof are incorporated herein.

Background

A waste combustion apparatus such as a garbage incinerator is generally an apparatus for burning solid fuel such as waste or biomass charged into a hopper in a combustion chamber. However, solid fuels such as waste and biomass have a characteristic that the variation in fuel properties is large, and there is a problem that the combustion state changes when the properties of the waste to be charged change. Therefore, the waste treatment apparatus is required to stabilize combustion.

For example, patent document 1 discloses the following method: when the volume density of the waste fed into the hopper is calculated and the amount of change from the previous volume density exceeds a predetermined threshold value, combustion control is performed according to the amount of change in the quality of the waste by correcting the heat generation amount reference value based on the amount of change in the volume density.

Prior art documents

Patent document

Patent document 1: japanese patent No. 6153090

Disclosure of Invention

Problems to be solved by the invention

However, if the change in the quality of the waste is determined based on the amount of change in the bulk density obtained from the entire waste in the hopper as in the method described in patent document 1, there is still a problem that it is not possible to cope with the change in the properties of the waste immediately before the waste is charged into the combustion chamber, and stable combustion control cannot be performed.

Accordingly, in some embodiments of the present invention, it is an object to provide a waste combustion apparatus and a waste combustion method which contribute to stabilization of a combustion state of waste.

Means for solving the problems

A waste combustion apparatus according to at least one embodiment of the present invention includes: a hopper into which waste is fed; a feeder that supplies the waste that is put into the hopper; a feeder provided in a combustion chamber where the waste is burned; a water content meter for measuring the water content of the waste; and a control device including a heat generation amount change determination unit that determines a change in the amount of heat generated by the waste based on the amount of moisture of the waste measured by the moisture meter, an adjustment value determination unit that determines an adjustment value of the operation amount of the feeder based on a determination result of the change in the amount of heat generation, and an operation amount control unit that controls the feeder based on the adjustment value.

A waste combustion method according to at least one embodiment of the present invention includes: the method includes a step of feeding waste into a hopper, a step of supplying the waste fed into the hopper to a feeder in a combustion chamber in which the waste is burned by using a feeder, a step of measuring a moisture content of the waste, a step of determining a change in a calorific value of the waste based on the moisture content of the waste measured by the moisture meter, a step of determining an adjustment value of an operation amount of the feeder based on a determination result of the change in the calorific value, and a step of controlling the feeder based on the adjustment value of the operation amount of the feeder.

Effects of the invention

According to some embodiments of the present invention, the change in the amount of heat generation of the waste is determined based on the amount of moisture of the waste measured by the moisture meter, and the adjustment value of the operation amount of the feeder is determined based on the determination result of the change in the amount of heat generation. As a result, by measuring the moisture content of the waste supplied into the combustion chamber, it is possible to detect a change in the quality of the waste before combustion, and to adjust the amount of heat input into the combustion chamber, which contributes to stabilization of the combustion state of the waste in the combustion chamber.

Drawings

Fig. 1 is a schematic configuration diagram of a waste combustion apparatus according to an embodiment of the present invention.

Fig. 2 is a block diagram of a control device according to an embodiment of the present invention.

Fig. 3 is a diagram showing an example of the water content of the waste and the cycle time of the feeder according to the embodiment of the present invention.

Fig. 4 is a block diagram of a control device according to another embodiment of the present invention.

Fig. 5 is a block diagram of a control device according to another embodiment of the present invention.

Fig. 6 is a graph showing a correlation between the moisture content and the calorific value of the waste according to the embodiment of the present invention.

Fig. 7 is a block diagram of a control device according to another embodiment of the present invention.

Fig. 8 is a flowchart of a waste combustion method according to an embodiment of the present invention.

Detailed Description

Hereinafter, several embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the constituent members described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention to these, and are merely illustrative examples. On the other hand, expressions such as "having", "including", or "having" one constituent element are not exclusive expressions that exclude the presence of other constituent elements.

Fig. 1 is a schematic configuration diagram of a waste combustion apparatus 100 according to an embodiment of the present invention.

Hereinafter, a waste combustion apparatus 100 according to an embodiment of the present invention will be described with reference to fig. 1. The waste combustion apparatus 100 may be an apparatus for incinerating municipal waste or the like, or may be an apparatus for incinerating industrial waste liquid or the like.

As shown in fig. 1, a waste combustion apparatus 100 according to an embodiment includes: a hopper 3 into which waste is fed, a feeder 5 which supplies the waste fed into the hopper 3 into a combustion chamber 11, a feeder 7 which receives the waste supplied from the feeder 5 and burns the waste, a combustion chamber 11 which burns the waste, a moisture meter 30 which measures the moisture content of the waste, and a control device 50. The waste combustion apparatus 100 according to the present embodiment may further include a blower 9 disposed below the feeder 7 and configured to supply air to the feeder 7, or may further include a boiler 15.

The hopper 3 temporarily stores the waste, and for example, the waste is thrown in by a crane (not shown) and stored.

The feeder 5 is provided at a lower portion of the hopper 3, and feeds the waste supplied to the feed table 5a through the chute portion 3a of the hopper 3 to the feeder 7 in the combustion chamber 11 by moving forward and backward with a predetermined stroke and pushing out the waste into the combustion chamber 11. The feeder 5 receives a control signal from the control device 50, controls the speed and operation timing of pushing out the waste, and controls the amount of waste supplied to the combustion chamber 11.

The feeder 7 is provided at the bottom of the combustion chamber 11, and is configured by alternately arranging a fixed grate and a movable grate that reciprocates in the flow direction of the garbage, and receives the waste supplied into the combustion chamber 11 by the feeder 5, and dries and combusts the waste while moving the waste.

The feeder 7 includes: a drying grate 7a that evaporates the moisture of the waste supplied from the feeder 5 to dry the waste, a combustion grate (front combustion grate) 7b that is located downstream of the drying grate 7a and burns the dried waste, and a post-combustion grate 7c that is located downstream of the combustion grate 7b and burns unburned components such as fixed carbon components that pass through without being combusted until ash is formed. The charging machine 7 receives a control signal from the control device 50 and controls the operating speed of each grate.

The downstream side of the post-combustion grate 7c is connected to an ash outlet 13, and ash is discharged from the waste combustion apparatus 100 through the ash outlet 13.

The blower 9 is provided below the feeder 7, and supplies primary air (air) to each part of the feeder 7 via the wind box 8. The combustion of the waste is promoted, for example, in the combustion grate 7b by the supplied primary air. The blower 9 receives a control signal from the control device 50 and controls the amount of air supplied.

The combustion chamber 11 includes a primary combustion chamber 11a and a secondary combustion chamber 11b above the charging machine, and a boiler 15 is connected and disposed downstream thereof. The primary combustion chamber 11a is an area in the furnace in which the waste charged into the furnace is incinerated with primary air from below the charging machine 7 while being transferred to the charging machine 7. The secondary combustion chamber 11b is an area in the furnace which is provided above the primary combustion chamber 11a and in which unburned gas generated from the primary combustion chamber 11a is subjected to secondary combustion by secondary air sent from a blower (not shown) provided in the secondary combustion chamber. Since the amount of air required for complete combustion of the waste changes when the amount of heat generation changes, the amount of air blown by the blower for sending the secondary air may be controlled by receiving a control signal from the control device 50.

A thermometer 12 for measuring the furnace temperature in the secondary combustion chamber 11b is provided in the combustion chamber 11. The thermometer 12 transmits information of the measured temperature in the furnace to the control device 50. In fig. 1, only one thermometer 12 is provided, but a plurality of thermometers may be provided in the secondary combustion chamber 11 b. The thermometer 12 may be provided at the outlet of the combustion chamber 11 or in a flue connected to the boiler 15, as long as it can grasp the combustion state in the combustion chamber.

The boiler 15 is disposed downstream of the flow of the exhaust gas generated in the combustion chamber 11, and generates steam using combustion heat generated in the combustion chamber 11. The boiler 15 generates steam by exchanging heat between the exhaust gas sent from the combustion chamber 11 and water circulating in the boiler 15. A flue is provided at an exhaust gas outlet of the boiler 15, and exhaust gas heat-recovered by the boiler 15 passes through the flue, passes through an exhaust gas treatment facility, and is discharged to the outside. A steam flow rate measuring device 16 for measuring a steam flow rate generated by heat exchange between the combustion exhaust gas and water is provided in the boiler 15. The steam flow rate meter 16 transmits information on the measured steam flow rate to the control device 50.

The exhaust gas heat-recovered by the boiler 15 passes through a flue and is treated by exhaust gas treatment equipment such as a desuperheater 17 for lowering the temperature of the exhaust gas and a dust collector 19 for removing fly ash and the like from the exhaust gas, and is discharged to the outside from a stack 21.

The moisture meter 30 measures the moisture content of the waste. The water content meter 30 may be any type of meter as long as it can measure the water content of the waste, and may be a meter that measures water content using, for example, a resistance value, a capacitance, a degree of light absorption, or an electromagnetic wave. As shown in fig. 1, the moisture meter 30 is preferably provided at a lower portion (near the outlet) in the hopper 3, that is, at a position where the moisture content of the waste immediately before being pushed out to the combustion chamber 11 by the feeder 5 can be measured. By being able to measure the moisture content of the waste immediately before supply to the combustion chamber 11, the moisture content of the waste supplied to the feeder 7 can be grasped before combustion.

In the embodiment shown in fig. 1, the moisture meter 30 is provided near the outlet in the hopper 3 in order to measure the moisture content of the waste near the outlet, but the position where the moisture meter 30 is provided is not limited to this case, and the moisture meter may measure the moisture content of the waste near the inlet or the outlet of the hopper 3.

The moisture meter 30 is not limited to the one shown in fig. 1 which can measure the moisture content of the waste at the outlet portion in the hopper 3, and may be provided at any position, for example, a position which can measure the moisture content of the waste at the center portion or the upper portion in the hopper 3. When the moisture meter 30 is provided at a position where the moisture amount of the waste in the center portion of the hopper 3 can be measured, the waste whose moisture amount has been measured is supplied to the combustion chamber 11 after a certain time, but the moisture amount of the waste supplied to the feeder 7 can be grasped by measuring the timing of the supply. The moisture meter 30 is not limited to the one provided in the hopper 3 and may be provided at an upper position upstream of the feeder 7, that is, at a position at which the moisture content of the waste immediately after being supplied into the combustion chamber 11 can be measured. When the moisture meter 30 is provided at a position where the moisture amount of the waste at an upper position upstream of the feeder 7 can be measured, the moisture amount of the waste supplied to the feeder 7 can be directly grasped. The moisture meter 30 is not limited to one, and may be provided in plural. For example, the temperature distribution of the waste in the hopper 3 may be measured accurately by providing the temperature distribution measuring device at a position where the moisture content of the waste above, in the center, or below the hopper can be measured.

Fig. 2 is a block diagram of a control device 50 according to an embodiment of the present invention.

As shown in fig. 2, the control device 50 includes: a heat generation amount change determination unit 52 that determines a change in the amount of heat generation of the waste; an adjustment value determination unit 54 that determines adjustment values of the operation amounts of the feeder 5 and the feeder 7 based on the determination result of the change in the amount of heat generation; an operation amount calculation unit 56 that calculates the operation amounts of the feeder 5 and the feeder 7 based on the target steam flow rate; and an operation amount control unit 58 for controlling the feeder 5 and the feeder 7 based on the operation amount calculated by the operation amount calculation unit 56 and the adjustment values of the operation amounts of the feeder 5 and the feeder 7 determined by the adjustment value determination unit 54.

The heat generation amount change determination unit 52 determines a change in the amount of heat generation of the waste based on the moisture amount of the waste measured by the moisture meter 30. The calorific value change determination unit 52 may receive information on the moisture content of the waste from the moisture meter 30, compare the information with a preset reference moisture content, and determine that the calorific value has changed when the difference exceeds a predetermined threshold value and increases or decreases. The reference moisture content is a reference value of the moisture content for grasping the change in the quality of the waste, and for example, the moisture content of the waste before a predetermined time may be set as the reference moisture content, or a moving average of the moisture contents of the waste acquired with time by the moisture meter 30 may be set as the reference moisture content. Further, for example, if the type of waste is determined to some extent, the user may set the reference moisture amount according to the type of waste.

The waste generally has a lower calorific value as the moisture content is higher, and has a higher calorific value as the moisture content is lower. Thus, the heat generation amount change determination unit 52 determines that the amount of heat generation of the waste is reduced when, for example, the moisture amount in the waste increases from the reference moisture amount by a predetermined threshold or more, and determines that the amount of heat generation of the waste increases when the moisture amount in the waste decreases from the reference moisture amount by a predetermined value or more. The calorific value change determination unit 52 transmits information on the amount of change of the amount of waste as a determination result to the adjustment value determination unit 54 when the amount of change of the calorific value of the waste increases or decreases by a predetermined value or more.

The adjustment value determining unit 54 determines the adjustment values of the operation amounts of the feeder 5 and the feeder 7 so that the heat input amount (the amount of the waste to be charged) to the combustion chamber 11 is constant, based on the determination result of the heat generation amount change determined by the heat generation amount change determining unit 52. The adjustment value determining unit 54 may determine the adjustment values of the operation amounts of the feeder 5 and the feeder 7 according to the amount of change in the amount of heat generation of the waste. The adjustment value determining unit 54 transmits information of the determined adjustment value to the operation amount control unit 58.

The operation amount calculation unit 56 calculates the operation amounts of the feeder 5 and the charger 7 so that the necessary waste (heat input amount) is charged into the combustion chamber 11, respectively, in order to match the steam flow rate measured by the steam flow rate meter 16 with the target steam flow rate of the boiler 15. More specifically, the operation amount calculation unit 56 calculates the operation amount of the feeder 5 so as to adjust the amount of the waste (heat input amount) supplied into the combustion chamber 11 so that the current steam flow rate matches the target steam flow rate, and calculates the operation amount of the loader 7 so as to adjust the combustion heat. The operation amount calculation unit 56 transmits the calculated operation amounts of the feeder 5 and the feeder 7 to the operation amount control unit 58. The target steam flow rate is a target steam flow rate generated in the boiler 15, and is appropriately set based on information such as the amount of power generated by a power generation device that generates power using steam.

The operation amount control unit 58 calculates the operation amounts of the feeder 5 and the feeder 7 calculated by the operation amount calculation unit 56 and the adjustment values of the operation amounts of the feeder 5 and the feeder 7 determined by the adjustment value determination unit 54, and controls the feeder 5 and the feeder 7, respectively.

Here, an example of adjustment of the operation amounts of the feeder 5 and the feeder 7 will be described with reference to fig. 3. When the reference moisture content is set to 50% and the heat generation amount change determination unit 52 determines that there is a change in the heat generation amount when the reference moisture content changes by a predetermined threshold value (2%) or more. When the moisture amount obtained from the moisture meter 30 is 53%, the heat generation amount change determination unit 52 determines that there is a change in the heat generation amount when the difference from the reference moisture amount is 2% or more. Next, the adjustment value determining unit 54 determines the adjustment value so as to increase the speed of the feeder 5, because the supply amount of the waste is increased to make the heat input constant. On the other hand, when the moisture amount is increased (the fuel calorie is decreased), there is a problem that the drying distance of the charger 7 becomes long and the burnout length increases. Therefore, the adjustment value determining unit 54 determines the adjustment value so as to decrease the stoker speed of the stoker and to decrease the burn-out length by decreasing the stoker speed of the combustion grate 7b and the post combustion grate 7c to increase the residence time.

According to the control device 50 of the embodiment shown in fig. 2, in order to match the target steam flow rate, the moisture content of the waste supplied to the combustion chamber is measured in addition to the operation amounts of the feeder 5 and the feeder 7 calculated by the operation amount calculation unit 56, thereby detecting a change in the quality of the waste before combustion, and the operation amounts of the feeder 5 and the feeder 7 in which the change in the quality is taken into account in advance can be adjusted, so that the combustion state and the evaporation amount can be stabilized.

Although the control device 50 of the embodiment shown in fig. 2 described above has been described with the operation amount calculation unit 56 provided, the operation amount calculation unit 56 may be omitted. For example, when the target steam flow rate is constant and the change in the properties of the waste is small, the operation amount of the feeder 5 or the like may be set in advance, and the operation amount control unit 58 may control the feeder 5 or the like by adding an adjustment value of the operation amount corresponding to the moisture amount of the waste to the operation amount of the feeder 5 or the like set in advance.

In addition, although the feeder 5 and the feeder 7 are described as the control targets in the adjustment value determining unit 54 and the operation amount control unit 58, the present disclosure is not limited to this, and for example, only the feeder 5 may be the control target if the burn-up length of the feeder 7 does not become a problem. That is, the amount of the waste supplied to the combustion chamber 11 may be adjusted by controlling the operation amount of the feeder 5 according to the moisture amount of the waste.

Fig. 4 is a block diagram of a control device 50 according to another embodiment of the present invention. Hereinafter, the same configuration as that of the control device 50 shown in fig. 2 will be appropriately omitted.

In the control device 50 of the embodiment shown in fig. 4, the heat generation amount change determination unit 52 may determine a change in the amount of heat generation of the waste in the combustion chamber 11 based on the gas temperature measured by the thermometer 12 in addition to the moisture amount of the waste measured by the moisture meter 30. The heat generation amount change determination unit 52 may receive information on the gas temperature in the combustion chamber 11 by the thermometer 12, compare the information with a preset reference gas temperature, and determine that the heat generation amount has changed when the difference exceeds a predetermined threshold and increases or decreases. The reference gas temperature is a reference value of the gas temperature for generating the target steam flow rate, and may be determined by the target steam flow rate. The heat generation amount change determination unit 52 may determine that the combustion heat of the waste on the loader 7 has changed when it is determined that the gas temperature has changed from the reference gas temperature by a predetermined threshold value or more, for example.

According to the above configuration, since the change in the amount of heat generated by the waste in the combustion chamber is determined based on the gas temperature, the steam flow rate, and the like in the combustion chamber in addition to the moisture amount of the waste, even when the amount of heat input to the waste supplied to the combustion chamber varies slightly, the variation in the combustion heat can be suppressed.

The adjustment value determination unit 54 may determine at least one adjustment value of the operation amount of the loader 7 and the operation amount of the blower 9 that supplies air to the loader 7 from below the loader 7 disposed at the bottom in the combustion chamber 11 when the generated heat amount change determination unit 52 determines that the gas temperature has changed by the predetermined threshold value or more.

For example, when the gas temperature decreases by a predetermined threshold value or more, the adjustment value determination unit 54 determines that the combustion heat of the waste on the loader 7 decreases, and determines the adjustment value of the operation amount of the blower 9 so that the primary air amount increases in order to promote the combustion of the waste.

The operation amount calculation unit 56 calculates the operation amount of the blower 9 in addition to the operation amounts of the feeder 5 and the feeder 7. The operation amount control unit 58 calculates the operation amounts of the feeder 5, the feeder 7, and the blower 9 calculated by the operation amount calculation unit 56 and the adjustment values of the operation amounts of the feeder 5, the feeder 7, and the blower 9 determined by the adjustment value determination unit 54, and controls the feeder 5, the feeder 7, and the blower 9, respectively. For example, when the heat generation amount change determination unit 52 determines that the gas temperature has changed from the reference gas temperature by a predetermined threshold value or more, the adjustment value determination unit 54 determines the adjustment value of the operation amount of the blower 9, and the operation amount control unit 58 adds the adjustment value of the operation amount of the blower 9 determined by the adjustment value determination unit 54 to the operation amount of the blower 9 calculated by the operation amount calculation unit 56. As a result, the combustion can be promoted by increasing the amount of primary air, and the amount of volatile matter generated from solid components of waste and biomass can be increased.

Fig. 5 is a block diagram of a control device 50 according to another embodiment of the present invention. In the following, the description of the configuration common to the control device 50 shown in fig. 2 is appropriately omitted.

The control device 50 shown in fig. 5 further includes: the waste heat recovery system includes a storage unit 60 that stores a correlation chart between the moisture content of the waste and the heat generation amount of the waste, a heat generation amount calculation unit 62 that calculates the heat generation amount from the steam flow rate measured by the steam flow rate meter 16, and an update unit 64 that updates the correlation chart stored in the storage unit 60 based on the heat generation amount calculated by the heat generation amount calculation unit 62 and the moisture content of the waste measured by the moisture meter 30.

The heat generation amount change determination unit 52 determines a change in the amount of heat generation of the waste based on the relationship between the amount of moisture of the waste measured by the moisture meter 30, the amount of moisture of the waste stored in the storage unit 60, and the amount of heat generation of the waste. In the present embodiment, the case where the relationship between the moisture content of the waste and the calorific value of the waste is stored in the storage unit 60 as the correlation table is exemplified, but the relationship may be stored in the storage unit 60 as the correspondence table. FIG. 6 is a correlation chart of an embodiment of the present invention. In the graph shown in fig. 6, the horizontal axis represents the moisture content of the waste, and the vertical axis represents the calorific value of the waste. Since the water content of the waste and the calorific value of the waste have a correlation, the calorific value can be calculated by using the correlation table when the water content of the waste is measured. Therefore, the generated heat amount change determination unit 52 acquires the moisture amount of the waste measured by the moisture meter 30, and then accesses the storage unit 60 to acquire the generated heat amount corresponding to the acquired moisture amount. The heat generation amount change determination unit 52 may acquire the heat generation amount from the moisture amount acquired after a predetermined time, and determine whether or not the heat generation amount has changed by a threshold value or more with respect to the previous heat generation amount.

The heating value calculation unit 62 calculates the heating value by acquiring the steam flow rate measured by the steam flow rate meter 16 and the moisture amount measured by the moisture meter 30. The heat generation amount calculation unit 62 transmits data of the water content and the heat generation amount calculated using the water content to the update unit 64.

The updating unit 64 reads the data of the correlation graph from the storage unit 60, adds the data of the water content and the heat generation amount acquired from the heat generation amount calculating unit 62, updates the correlation graph of the water content and the heat generation amount, and stores the updated correlation graph in the storage unit 60. The updating unit 64 updates the correlation table stored in the storage unit 60 based on the amount of heat generation and the amount of moisture of the waste measured by the moisture meter 30, thereby updating the correlation table as needed, and thus, the correlation table becomes a correlation table according to the change in the quality of the waste, and the change in the amount of heat generation can be accurately determined, and the adjustment value of the adjustment target (the feeder 5, the feeder 7, the blower 9, and the like) can be calculated, so that the combustion state can be stabilized.

According to the control device 50 shown in fig. 5, since the heat generation amount calculation unit 62 and the update unit 64 prepare the correlation table reflecting the quality of the waste that can change at any time in real time and the heat generation amount change determination unit 52 determines that the heat generation amount has changed, the change in the quality of the waste can be more accurately reflected in the control of the adjustment target (the feeder 5, the feeder 7, the blower 9, and the like).

The control device 50 shown in fig. 5 has been described by taking as an example the case where the generated heat amount calculation unit 62 and the update unit 64 are provided, but the present invention is not limited thereto and these may be omitted. For example, when the type of waste is determined to some extent by day and season, the user may appropriately select a correlation chart corresponding to the type of waste.

Fig. 7 is a block diagram of a control device 50 according to another embodiment of the present invention. In the following, the description of the configuration common to the above-described control device 50 is appropriately omitted.

In the control device 50 shown in fig. 7, the storage unit 60 stores an operation amount map indicating a correspondence relationship between the target steam flow rate of the boiler 15 and the calorific value change information of the waste and the adjustment value of the feeder 5, and the adjustment value determination unit 54 determines the adjustment value of the operation amount of the feeder 5 based on the result of the calorific value change, the target steam flow rate of the boiler 15, and the operation amount map stored in the storage unit 60. The operation amount map is a map in which adjustment values of the operation amounts of the feeder 5 and the feeder 7 that are the target steam flow rates are calculated by thermal fluid analysis or the like, for example, based on the result of the change in the calorific value and the input of the gas temperature and the steam flow rate.

According to the above configuration, the operation amount of the feeder 5 is adjusted using the information of the target steam flow rate of the boiler 15, and therefore the target steam flow rate can be more achieved.

Specifically, the adjustment value determining unit 54 receives the result of the change in the heating value, the input of the gas temperature, and the input of the steam flow rate, reads the operation amount map from the storage unit 60, and determines the adjustment values of the operation amounts of the feeder 5 and the feeder 7 based on the operation amount map.

By using the manipulated variable map, the adjusted value of the manipulated variable of the feeder 5 and the like calculated by the thermal fluid analysis can be accurately determined, and the adjusted value of the manipulated variable can be given as a preceding signal (japanese: preceding signal), so that the fluctuation of the steam flow rate can be quickly suppressed.

In the control device 50 shown in fig. 7, instead of the above-described operation amount map, the storage unit 60 may store a dynamic physical model of the waste combustion device 100, and the adjustment value determination unit 54 may acquire the target steam flow rate of the boiler 15 and the heat generation amount change information of the waste, and may determine the adjustment value of the operation amount of the feeder 5 based on the dynamic physical model stored in the storage unit 60. That is, the calculation is performed by a dynamic physical model showing the effect of the external force such as the feeder 5 on the components of the result of the change in the calorific value, the gas temperature, and the steam flow rate. The physical model can be obtained by theoretical calculation.

The adjustment value of the operation amount of the feeder 5 can be determined more precisely by calculating the adjustment value of the operation amount of the feeder 5 by a dynamic physical model from the target steam flow rate of the boiler 15 and the operation amount of the feeder 5, in addition to the heat generation amount change information of the waste.

Fig. 8 is a flowchart of a waste combustion method according to an embodiment of the present invention. Hereinafter, a waste combustion method according to an embodiment will be described with reference to fig. 8. The case where the feeder 5 is controlled by using the control device 50 shown in fig. 2 will be described as an example.

An embodiment waste combustion method includes: a step of feeding waste into the hopper 3 (S1), a step of supplying the waste fed into the hopper 3 to the feeder 7 in the combustion chamber 11 where the waste is burned by using the feeder 5 (S2), a step of measuring the moisture content of the waste (S3), a step of determining a change in the amount of heat generation of the waste based on the moisture content of the waste measured by the moisture meter 30 (S4), a step of determining an adjustment value of the operation amount of the feeder 5 based on the result of the change in the amount of heat generation (S5), and a step of controlling the feeder 5 based on the adjustment value of the operation amount of the feeder 5 (S6).

The controller 50 specifically performs the following operations in each of the above-described stages S2 to S6. In step S2, the operation amount calculation unit 56 calculates the operation amount of the feeder 5 so that the steam flow rate obtained from the steam flow rate meter 16 matches the target steam flow rate, and the operation amount control unit 58 operates the feeder 5 based on the calculated operation amount, and supplies the waste charged into the hopper 3 to the feeder 7 in the combustion chamber 11 where the waste is burned, using the feeder 5.

In step S3, the water content meter 30 measures the water content of the waste, and the control device 50 receives information on the measured water content of the waste. The timing for measuring the water content of the waste can be set as appropriate.

In step S4, the heat generation amount change determination unit 52 determines whether or not the heat generation amount change of the waste is equal to or greater than a predetermined threshold value based on the moisture amount of the waste measured by the moisture meter 30.

In step S5, the adjustment value determination unit 54 determines the adjustment value of the operation amount of the feeder 5 based on the result of the change in the heat generation amount. In the case of the determination result that the heat generation amount has changed to a predetermined threshold value or more, the adjustment value determination unit 54 determines an adjustment value corresponding to the change amount, and in the case of the determination result that the heat generation amount has not changed to a predetermined threshold value or more, the adjustment value determination unit 54 determines the adjustment value to be 0.

In step S6, the operation amount control unit 58 controls the operation amount of the feeder 5 based on the adjustment value of the operation amount of the feeder 5.

In the present waste combustion method, a change in the amount of heat generation of the waste is determined based on the amount of moisture of the waste measured by the moisture meter 30, and an adjustment value of the operation amount of the feeder 5 is determined based on the result of the change in the amount of heat generation. As a result, the amount of the waste introduced into the combustion chamber 11 can be adjusted, and the amount of heat input into the combustion chamber 11 can be adjusted, which contributes to stabilization of the combustion state of the waste in the combustion chamber 11 and stabilization of the steam flow rate. Further, the moisture meter 30 measures the moisture amount of the waste at an arbitrary position, and determines a change in the amount of heat generation of the waste based on the measured moisture amount to reflect the change in the amount of the waste charged into the combustion chamber 11, thereby contributing to further stabilization of the combustion state of the waste and stabilization of the steam flow rate.

The waste combustion apparatus 100 according to each embodiment is grasped as follows, for example.

(1) The waste combustion apparatus 100 of the first embodiment includes: a hopper 3 into which waste is fed; a feeder 5 for supplying the waste fed into the hopper 3; a feeder 7 disposed in a combustion chamber 11 for burning waste; a boiler 15 for generating steam by using combustion heat generated in the combustion chamber 11; a moisture meter 30 for measuring the moisture content of the waste; and a control device 50 including a heat generation amount change determination unit 52 for determining a change in the amount of heat generation of the waste based on the amount of moisture of the waste measured by the moisture meter 30, an adjustment value determination unit 54 for determining an adjustment value of the operation amount of the feeder 5 based on the determination result of the change in the amount of heat generation, and an operation amount control unit 58 for controlling the feeder 5 based on the adjustment value of the operation amount of the feeder 5 determined by the adjustment value determination unit 54.

In the waste combustion apparatus 100 of the first embodiment, a change in the amount of heat generation of the waste is determined based on the moisture amount of the waste measured by the moisture meter 30, and an adjustment value of the operation amount of the feeder 5 is determined based on the result of the change in the amount of heat generation. As a result, the amount of the waste introduced into the combustion chamber 11 can be adjusted, and the amount of heat input into the combustion chamber 11 can be adjusted, which contributes to stabilization of the combustion state of the waste in the combustion chamber 11 and stabilization of the steam flow rate. Further, the moisture meter 30 measures the moisture amount of the waste at an arbitrary position, and determines the change in the amount of heat generation of the waste based on the measured moisture amount to reflect the change in the amount of the waste charged into the combustion chamber 11, thereby contributing to further stabilization of the combustion state of the waste and stabilization of the steam flow rate.

(2) The waste combustion apparatus 100 according to the second aspect is the waste combustion apparatus 100 according to the first aspect, further including: a boiler 15 for generating steam by using combustion heat generated in the combustion chamber 11; and a steam flow rate measuring unit 16 that measures the steam flow rate of the boiler 15, wherein the control device 50 further includes an operation amount calculating unit 56, the operation amount calculating unit 56 calculates the operation amount of the feeder 5 so that the steam flow rate measured by the steam flow rate measuring unit 16 matches the target steam flow rate of the boiler 15, and the operation amount controlling unit 58 calculates the operation amount of the feeder 5 calculated by the operation amount calculating unit 56 and the adjustment value of the operation amount of the feeder 5 determined by the adjustment value determining unit 54 to control the feeder 5.

In the waste combustion apparatus 100 of the second embodiment, the operation amount of the feeder 5 is calculated so that the target steam flow rate of the boiler 15 matches the steam flow rate measured by the steam flow rate measuring device 16, and the operation amount of the feeder 5 is adjusted based on the operation amount of the feeder 5 and the result of change in the heat generation amount based on the moisture amount of the waste. As a result, the operation amount of the feeder is determined so as to be the target steam flow rate, and the operation amount is adjusted in accordance with the moisture amount of the waste, so that it is possible to respond quickly to a change in the target steam flow rate.

(3) The waste combustion apparatus 100 according to the third aspect calculates the operation amounts of the feeder 5 and the feeder 7 so that the steam flow rate measured by the steam flow rate measuring unit 16 coincides with the target steam flow rate of the boiler 15, based on the waste combustion apparatus 100 according to the second aspect, the operation amount calculating unit 56 determines the adjustment values of the operation amounts of the feeder 5 and the feeder 7 based on the determination result of the change in the calorific value, and the operation amount controlling unit 58 calculates the operation amounts of the feeder 5 and the feeder 7 calculated by the operation amount calculating unit 56 and the adjustment values of the operation amounts of the feeder 5 and the feeder 7 determined by the adjustment value determining unit 54 to control the feeder 5 and the feeder 7.

In the waste combustion apparatus 100 of the third aspect, the operation amounts of the feeder 5 and the feeder 7 are determined so that the target steam flow rate of the boiler 15 matches the steam flow rate measured by the steam flow rate measuring device 16, and the operation amounts of the feeder 5 and the feeder 7 are adjusted based on the result of a change in the amount of heat generated based on the moisture content of the waste. As a result, the supply amount of the waste, that is, the heat input amount, to the combustor 11 can be controlled by the feeder 5 according to the moisture amount of the waste, and the combustion state of the waste can also be controlled, thereby stabilizing the steam flow rate.

(4) The waste combustion device 100 according to the fourth aspect is the waste combustion device 100 according to the first to third aspects, wherein the heat generation amount change determination unit 52 determines the change in the amount of heat generation of the waste based on the difference between the moisture amount of the waste and the moisture amount of the waste before a predetermined time or the moving average of the moisture amounts of the waste taken with time.

In the waste combustion apparatus 100 of the fourth aspect, by determining a change in the amount of heat generation of the waste when a difference occurs between the amount of moisture of the waste and the amount of moisture of the waste before a predetermined time or a moving average of the amounts of moisture of the waste taken over time, even if the quality (amount of moisture) of the waste changes, the objects to be adjusted (the feeder 5, the feeder 7, the blower 9, and the like) can be controlled based on the change in the amount of heat generation, and this can contribute to stabilization of the combustion state and stabilization of the steam flow rate.

(5) The waste combustion apparatus 100 according to the fifth aspect is the waste combustion apparatus 100 according to the first to third aspects, wherein the control device 50 further includes a storage unit 60 that stores a relationship between the moisture content of the waste and the amount of heat generation of the waste, and the heat generation amount change determination unit 52 determines a change in the amount of heat generation of the waste based on the relationship between the moisture content of the waste measured by the moisture meter 30, the moisture content of the waste stored in the storage unit 60, and the amount of heat generation of the waste.

In the waste combustion apparatus 100 according to the fifth aspect, even if the quality of the waste changes, the feeder 5 can be controlled so that the amount of heat input to the combustion chamber 11 is constant based on the change in the amount of heat generated determined from the graph of the water content of the waste and the correlation graph, and this can contribute to the stabilization of the combustion state and the stabilization of the steam flow rate.

(6) The waste combustion apparatus 100 according to the sixth aspect is the waste combustion apparatus 100 according to the fifth aspect, wherein the control device 50 further includes: a calorific value calculation unit 62 that calculates a calorific value from the steam flow rate measured by the steam flow rate meter 16; and an updating unit 64 that updates the relationship between the moisture content of the waste and the calorific value of the waste stored in the storage unit 60, based on the calorific value calculated by the calorific value calculating unit 62 and the moisture content of the waste measured by the moisture meter 30.

In the waste combustion apparatus 100 according to the sixth aspect, the correlation table is updated as needed based on the calorific value calculated by the calorific value calculation unit 62 and the moisture content of the waste measured by the moisture meter 30, so that the change in the calorific value can be determined in accordance with the current situation.

(7) The waste combustion apparatus 100 according to the seventh aspect further includes a thermometer 12 for measuring a gas temperature in the combustion chamber 11, and the heat generation amount change determination unit 52 determines a change in the amount of heat generation of the waste in the combustion chamber 11 based on the moisture amount of the waste measured by the moisture meter 30 and the gas temperature measured by the thermometer 12, according to the waste combustion apparatuses 100 according to the first to sixth aspects.

In the waste combustion apparatus 100 of the seventh aspect, since the change in the amount of heat generation is determined by further using the gas temperature, the change in the amount of heat generation can be determined based on more information in the combustion chamber 11.

(8) The waste combustion apparatus 100 according to the eighth aspect is the waste combustion apparatus 100 according to the seventh aspect, wherein the adjustment value determining unit 54 determines at least one of the adjustment value of the operation amount of the loader 7 and the adjustment value of the operation amount of the blower 9 for supplying air to the loader 7 from below the loader 7 disposed at the bottom of the combustion chamber 11 when the heat generation amount change determining unit 52 determines that the gas temperature has changed by a predetermined amount or more, and the operation amount control unit 58 controls at least one of the loader 7 and the blower 9 based on at least one of the adjustment value of the operation amount of the loader 7 determined by the adjustment value determining unit 54 and the adjustment value of the operation amount of the blower 9 determined by the adjustment value determining unit 54.

In the waste combustion apparatus 100 according to the eighth aspect, when the gas temperature changes by a predetermined amount or more, the operation amount of the feeder 7 or the blower 9 is adjusted, so that the combustion state of the waste on the feeder 7 can be controlled, and the combustion state can be stabilized.

(9) The waste combustion apparatus 100 according to the ninth aspect is the waste combustion apparatus 100 according to the first to eighth aspects, wherein the feeder 7 includes a drying grate 7a for drying the waste supplied from the feeder 5 and a combustion grate 7b disposed downstream of the drying grate 7a, the adjustment value determining unit 54 determines the adjustment value of the speed of the combustion grate 7b of the feeder 7 based on the moisture content of the waste measured by the moisture meter 30, and the operation amount control unit 58 controls the speed of the combustion grate 7b based on the adjustment value of the speed of the combustion grate 7b determined by the adjustment value determining unit 54.

In the waste combustion apparatus 100 of the ninth aspect, the speed of the combustion grate 7b is adjusted based on the moisture content of the waste measured by the moisture meter 30, so that the combustion state of the waste on the combustion grate 7b can be controlled, and complete combustion of the waste on the combustion grate 7b can be promoted.

(10) The waste combustion apparatus 100 according to the tenth aspect is the waste combustion apparatus 100 according to the fifth aspect, wherein the storage unit 60 stores an operation amount map indicating a correspondence relationship between the target steam flow rate of the boiler 15, the heat generation amount change information of the waste, and the adjustment value of the feeder 5, and the adjustment value determination unit 54 determines the adjustment value of the operation amount of the feeder 5 based on the result of the change in the heat generation amount, the target steam flow rate of the boiler 15, and the operation amount map stored in the storage unit 60.

In the waste combustion apparatus 100 according to the tenth aspect, the adjustment value of the operation amount of the feeder 5 is determined based on the operation amount map indicating the correspondence relationship between the target steam flow rate of the boiler 15, the heat generation amount variation information of the waste, and the adjustment value of the feeder 5, and thus the operation amount of the feeder 5 can be adjusted using the information of the target steam flow rate of the boiler 15, and therefore the target steam flow rate can be more achieved.

(11) In the waste combustion apparatus 100 according to the eleventh aspect, the storage unit 60 stores a dynamic physical model of the waste combustion apparatus 100, and the adjustment value determination unit 54 obtains the target steam flow rate of the boiler 15 and the information on the change in the calorific value of the waste, and determines the adjustment value of the operation amount of the feeder 5 based on the dynamic physical model stored in the storage unit 60.

In the waste combustion apparatus 100 according to the eleventh aspect, the adjustment value of the operation amount of the feeder 5 can be determined more precisely by calculating the adjustment value of the operation amount of the feeder 5 using the dynamic physical model.

(12) The waste combustion apparatus 100 according to the twelfth aspect is the waste combustion apparatus 100 according to the first aspect, wherein the moisture meter 30 is provided near an inlet or an outlet of the hopper 3 into which waste is fed, and measures the moisture content of the waste.

In the waste combustion apparatus 100 of the twelfth aspect, the moisture meter 30 is provided near the inlet of the hopper 3, so that the moisture amount of the waste immediately after being supplied to the hopper 3 can be measured. Further, by providing the moisture meter 30 near the outlet of the hopper 3, the moisture amount of the waste immediately before being supplied to the combustion chamber 11 can be measured, and the moisture amount of the waste supplied to the feeder 7 can be grasped before combustion.

(13) A waste combustion method according to a thirteenth aspect includes: a stage S1 in which the waste is charged into the hopper 3 at the stage S1; a step S2 of supplying the wastes loaded in the hopper 3 to the feeder 7 in the combustion chamber 11 where the wastes are burned by using the feeder 5 at the step S2; a step S3 of measuring the moisture content of the waste at the step S3; a step S4 of determining a change in the calorific value of the waste based on the moisture content of the waste measured by the moisture meter 30 at the step S4; a step S5 of determining an adjustment value of the operation amount of the feeder 5 based on the determination result of the change in the heat generation amount in the step S5; and a stage S6 in which the feeder 5 is controlled based on the adjustment value of the operation amount of the feeder 5 in the stage S6.

In the waste combustion method of the thirteenth aspect, the change in the amount of heat generation of the waste is determined based on the moisture amount of the waste measured by the moisture meter 30, and the adjustment value of the operation amount of the feeder 5 is determined based on the result of the change in the amount of heat generation. As a result, the amount of the waste charged into the combustion chamber 11 can be adjusted, and the amount of heat input into the combustion chamber 11 can be adjusted, which contributes to stabilization of the combustion state of the waste in the combustion chamber 11 and stabilization of the steam flow rate. Further, the moisture meter 30 measures the moisture amount of the waste at an arbitrary position, determines a change in the amount of heat generation based on the measured moisture amount, and reflects the change in the amount of the waste charged into the combustion chamber 11, thereby contributing to further stabilization of the combustion state of the waste and stabilization of the steam flow rate.

The present invention is not limited to the above-described embodiments, and includes embodiments in which modifications are made to the above-described embodiments and embodiments in which these embodiments are appropriately combined.

Industrial applicability of the invention

The present invention relates to a waste combustion apparatus such as a garbage incinerator and a waste combustion method. According to the present invention, the combustion state of the waste in the combustion chamber can be stabilized.

Description of the reference numerals

3 hopper

5 feeder

7 charger

8 air bellow

9 blower

11 combustion chamber

13 ash outlet

15 boiler

16 steam flow meter

17 temperature reducing tower

19 dust collector

21 chimney

30 moisture meter

50 control device

52 heating value change determination unit

54 adjustment value determining part

56 operation amount calculating part

58 operation amount control part

60 storage unit

62 calorific value calculation unit

64 update part

100 waste combustion device.

Claims (13)

1. A waste combustion apparatus, wherein,

the waste combustion apparatus comprises:

a hopper into which waste is fed;

a feeder that supplies the waste that is put into the hopper;

a feeder provided in a combustion chamber where the waste is burned;

a water content meter for measuring the water content of the waste supplied to the feeder; and

a control device for controlling the operation of the motor,

the control device is provided with:

a heat generation amount change determination unit that determines a change in the amount of heat generation of the waste based on the amount of moisture of the waste measured by the moisture meter;

an adjustment value determination unit that determines an adjustment value for the operation amount of the feeder based on the determination result of the change in the heat generation amount; and

and an operation amount control unit that controls the feeder based on the adjustment value.

2. The waste combustion apparatus of claim 1,

the waste combustion apparatus further includes:

a boiler for generating steam by using combustion heat generated in the combustion chamber; and

a steam flow rate measuring device for measuring a steam flow rate of the boiler,

the control device further includes an operation amount calculation unit that calculates an operation amount of the feeder so that the steam flow rate measured by the steam flow rate measurement unit matches a target steam flow rate of the boiler,

the operation amount control unit calculates the operation amount of the feeder calculated by the operation amount calculation unit and the adjustment value of the operation amount of the feeder determined by the adjustment value determination unit, to control the feeder.

3. The waste combustion apparatus of claim 2,

the operation amount calculation unit calculates the operation amounts of the feeder and the charger so that the steam flow rate measured by the steam flow rate measuring device coincides with a target steam flow rate of the boiler,

the adjustment value determination unit determines adjustment values of the operation amounts of the feeder and the feeder based on the determination result of the change in the heat generation amount,

the operation amount control unit calculates the operation amounts of the feeder and the feeder calculated by the operation amount calculation unit and the adjustment values of the operation amounts of the feeder and the feeder determined by the adjustment value determination unit to control the feeder and the feeder, respectively.

4. The waste combustion apparatus as claimed in any one of claims 1 to 3, wherein,

the heat generation amount change determination unit determines a change in the amount of heat generation of the waste based on a difference between the moisture amount of the waste and the moisture amount of the waste before a predetermined time or a moving average of the moisture amount of the waste taken over time.

5. The waste combustion apparatus as claimed in claim 2 or 3, wherein,

the control device further includes a storage portion that stores a relationship between the moisture amount of the waste and the calorific value of the waste,

the heat generation amount change determination unit determines a change in the amount of heat generation of the waste based on a relationship among the amount of moisture of the waste measured by the moisture meter, the amount of moisture of the waste stored in the storage unit, and the amount of heat generation of the waste.

6. The waste combustion apparatus of claim 5,

the control device further includes:

a calorific value calculation unit that calculates a calorific value from the steam flow measured by the steam flow meter; and

and an updating unit that updates the relationship between the amount of moisture of the waste stored in the storage unit and the amount of heat generation of the waste, based on the amount of heat generation calculated by the heat generation amount calculating unit and the amount of moisture of the waste measured by the moisture meter.

7. The waste combustion device of any one of claims 1 to 6,

the waste combustion apparatus further comprises a thermometer for measuring a gas temperature in the combustion chamber,

the heat generation amount change determination unit determines a change in the amount of heat generation of the waste in the combustion chamber based on the amount of moisture of the waste measured by the moisture meter and the gas temperature measured by the thermometer.

8. The waste combustion apparatus of claim 7,

the adjustment value determining unit determines at least one of an adjustment value of an operation amount of the loader and an adjustment value of an operation amount of a blower that supplies air to the loader from below the loader arranged at the bottom in the combustion chamber when the heat generation amount change determining unit determines that the gas temperature has changed by a predetermined amount or more,

the operation amount control unit controls at least one of the feeder and the blower based on at least one of the adjustment value of the operation amount of the feeder determined by the adjustment value determining unit and the adjustment value of the operation amount of the blower determined by the adjustment value determining unit.

9. The waste combustion apparatus as in any one of claims 1 to 8,

the feeder includes a drying grate for drying the waste supplied from the feeder and a combustion grate disposed downstream of the drying grate,

the adjustment value determining section determines an adjustment value of the speed of the combustion grate of the charging machine based on the moisture content of the waste measured by the moisture meter,

the operation amount control unit controls the speed of the combustion grate based on the adjustment value of the speed of the combustion grate determined by the adjustment value determination unit.

10. The waste combustion apparatus of claim 5,

the storage unit stores an operation amount map indicating a correspondence relationship between a target steam flow rate of the boiler, calorific value variation information of the waste, and an adjustment value of the feeder,

the adjustment value determination unit determines the adjustment value of the operation amount of the feeder based on the result of the change in the calorific value, the target steam flow rate of the boiler, and the operation amount map stored in the storage unit.

11. The waste combustion apparatus of claim 5,

the storage unit stores a dynamic physical model of the waste combustion apparatus,

the adjustment value determining unit obtains a target steam flow rate of the boiler and calorific value change information of the waste, and determines an adjustment value of an operation amount of the feeder based on the dynamic physical model stored in the storage unit.

12. The waste combustion apparatus of claim 1,

the moisture meter is provided near an inlet or an outlet of a hopper into which the waste is fed, and measures a moisture content of the waste.

13. A method for burning waste, wherein,

the waste combustion method comprises the following steps:

a charging step of charging waste into a hopper;

a supply step of supplying the waste fed into the hopper to a feeder in a combustion chamber where the waste is burned, by using a feeder;

a measuring step of measuring a moisture content of the waste;

a determination step of determining a change in the amount of heat generation of the waste based on the amount of moisture of the waste measured in the measurement step;

a determination step of determining an adjustment value of the operation amount of the feeder based on a determination result of the change in the heat generation amount; and

a control stage in which the feeder is controlled based on an adjustment value of an operation amount of the feeder.

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