JP2005274049A - Waste supply amount adjustment method in waste treatment equipment - Google Patents

Abstract

A waste supply amount adjusting method in a waste treatment apparatus capable of controlling a waste supply amount with high accuracy is provided.
Waste material a is supplied into a thermal decomposition drum 2 by a supply device 1 actively driven by an electric motor 4, and the waste material a is indirectly heated by heated air b1 to decompose cracked gas G and thermal decomposition residue c. And a pyrolysis residue c is separated into a combustion component d and a non-combustion component e, and the cracked gas G and the combustion component d are combusted. The temperature of the waste in the pyrolysis drum 2 is detected by temperature sensors 6a to 6d, and when the temperature of the waste in the pyrolysis drum 2 deviates from a set temperature, the electric motor 4 is controlled to generate heat from the supply device 1. The supply amount of the waste a supplied into the decomposition drum 2 is adjusted.
[Selection] Figure 1

Description

  The present invention relates to a waste supply amount adjusting method in a waste treatment apparatus for treating waste containing combustibles such as municipal waste and waste plastic.

Conventionally, as a waste treatment apparatus containing combustibles such as municipal waste and waste plastic, waste a is supplied to the horizontal rotary drum 2 and the waste is thermally decomposed while keeping the horizontal rotary drum 2 in a low oxygen atmosphere. The cracked gas G1 and the cracked residue c are generated, and the cracked residue c is further separated into the combustible component d and the incombustible component e. A waste treatment apparatus in which the supply amount of the cracked gas G1 supplied to the melting furnace 8 is detected by the detector 25 and the supply amount of the waste a is controlled by the control device 26. It is known (for example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 10-2525 (page 3-4, FIG. 1)

  However, since the generation amounts of the cracked gas G1 and the combustible component d vary greatly depending on the properties (waste quality) of the waste a, it is difficult to accurately control the supply amount of the waste a.

  Further, as described above, even if the supply amount of the decomposition gas G1 supplied to the melting furnace 8 is detected by the detector 25 and the supply amount of the waste a is controlled, the waste a is rotated horizontally by the screw feeder 3. Since there is a time lag until the drum 2 is supplied and thermally decomposed, it is difficult to stabilize the combustion in the melting furnace 8.

  By the way, the thermal decomposition drum which is a horizontal rotary drum is designed to treat waste in which the waste quality and the amount of waste are distributed as shown in FIG. 2, but the temperature of the waste in the thermal decomposition drum is As shown in FIG. 3, it varies greatly depending on the properties (waste quality) of the waste. For example, when only high-calorie waste (for example, waste of 3000 kcal / kg or more) is processed, only the low-calorie waste (for example, waste of 1000 kcal / kg or less) is shown as a solid line. Is processed like a one-dot chain line.

  That is, when there is a lot of high-calorie waste, the temperature of the waste in the pyrolysis drum rises gradually as it goes from the entrance to the exit of the pyrolysis drum as shown by the solid line, and is almost constant near the exit. Become. On the other hand, when there is a lot of low-calorie waste, the temperature of the waste in the pyrolysis drum rises gradually as it moves from the entrance to the exit of the horizontal rotary drum as shown by the one-dot chain line. It rapidly rises from the time when it passes through the evaporation zone A where the water contained in the gas evaporates and shifts to the thermal decomposition zone C, and reaches a temperature substantially equal to that of high-calorie waste near the outlet. Incidentally, B is an intermediate zone that moves from the evaporation zone A to the thermal decomposition zone C.

  Therefore, when controlling the temperature of the waste in the pyrolysis drum to a predetermined temperature, near the inlet of the pyrolysis drum where there is substantially no temperature difference depending on the waste quality, or near the outlet where the temperature difference is slight It is more accurate to measure the temperature of the waste in the pyrolysis drum by installing a temperature sensor in the other part, especially the pyrolysis zone after the evaporation zone where the water contained in the waste evaporates It can be measured well.

  The present invention has been made based on such knowledge, and one of its purposes is a waste supply amount adjustment method in a waste treatment apparatus that can control the supply amount of waste with high accuracy. It is to provide.

  That is, the present invention is configured as follows.

  According to the first aspect of the present invention, waste is supplied into the pyrolysis drum by a supply device actively driven by an electric motor, and the waste is indirectly heated by heated air to generate cracked gas and pyrolysis residue. In addition, in the waste treatment apparatus in which the pyrolysis residue is separated into a combustion component and a non-combustion component, and the cracked gas and the combustion component are burned, the temperature of the waste in the pyrolysis drum is set to a temperature. It is detected by a sensor, and when the temperature of the waste in the pyrolysis drum deviates from a set temperature, the electric motor is controlled to adjust the amount of waste supplied from the supply device into the pyrolysis drum. This is a waste supply amount adjustment method in a waste treatment apparatus.

  According to a second aspect of the present invention, the temperature of the waste in the pyrolysis zone is detected by a temperature sensor provided in the pyrolysis zone of the pyrolysis drum, and when the temperature deviates from a set temperature, the electric motor is controlled. 2. The waste supply amount adjustment method in the waste treatment apparatus according to claim 1, wherein the supply amount of waste supplied from the supply device into the pyrolysis drum is adjusted.

  As described above, according to the first aspect of the present invention, the waste is supplied into the pyrolysis drum by the supply device actively driven by the electric motor, and the waste is indirectly heated by the heated air to decompose the cracked gas and the pyrolysis. In the waste treatment apparatus that generates a residue, separates the pyrolysis residue into a combustion component and a non-combustion component, and burns the cracked gas and the combustion component, the waste in the pyrolysis drum The temperature of the object is detected by a temperature sensor, and when the temperature of the waste in the pyrolysis drum deviates from the set temperature, the electric motor is controlled to adjust the amount of waste supplied to the pyrolysis drum from the supply device Therefore, the temperature variation of the waste in the pyrolysis drum can be immediately fed back to the waste supply device. As a result, since there is less time delay compared to the conventional case where the amount of waste supplied is controlled according to the variation of cracked gas at the combustion device inlet, the cracked gas combustion process can be performed stably. Can do.

  In the invention according to claim 2, since the temperature of the waste in the pyrolysis zone is detected by the temperature sensor provided in the pyrolysis zone of the pyrolysis drum, the temperature of the waste in the pyrolysis drum is controlled. It can be detected with high accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a waste treatment apparatus for carrying out a waste supply amount adjusting method according to the present invention. As shown in FIG. 1, the waste treatment apparatus includes a supply device 1 that includes an electric motor 4 and a screw feeder 3, and a thermal decomposition drum 2 that is a horizontal rotary drum.

  The waste a supplied to the pyrolysis drum 2 by the supply device 1 is heated at a high temperature (for example, about 520 ° C.) supplied from the line L1 to a number of heating tubes (not shown) in the pyrolysis drum 2. It is indirectly heated by the air b1 and thermally decomposed into a cracked gas G and a pyrolysis residue c. The cracked gas G and the pyrolysis residue c are separated by the discharge device 7. The pyrolysis residue c after the cracked gas G and the incombustible material are separated and removed is subjected to a combustion treatment by a melting furnace (not shown).

  The pyrolysis drum 2 includes a plurality of temperature sensors 6a to 6d, and detects the temperature of the waste in the pyrolysis drum 2. More specifically, the pyrolysis drum 2 has a first temperature sensor 6a at the inlet and a fourth temperature sensor 6d at the outlet. The pyrolysis drum 4 further includes a second temperature sensor 6b in the intermediate zone B that transitions from the evaporation zone A to the pyrolysis zone C, and a third temperature sensor 6c in the pyrolysis zone C. .

  Here, the evaporation zone A is an area where moisture contained in the waste a is evaporated, the thermal decomposition zone C is an area where the thermal decomposition of the waste a is substantially performed, and the intermediate zone B is An area between the evaporation zone A and the pyrolysis zone C where the waste a moves from the evaporation zone A to the pyrolysis zone C.

  The control device 26 includes a storage device 28, a comparator 27, a first calculator 29a that inputs the first signal V12 of the comparator 27, and a second calculator 29b that inputs the second signal V13 of the comparator 27. The first control signal generator 30a that generates the first control signal V16 by inputting the signal V14 of the first calculator 29a and the second control signal V17 that receives the signal V15 of the second calculator 29b. The second control signal generator 30b is used. The storage device 28 is previously input with the waste temperature (for example, 320 ° C.) in the pyrolysis zone C of the pyrolysis drum 2.

  Subsequently, the operation of the waste treatment apparatus will be described.

  Now, the signal V3 of the third temperature sensor 6c is compared with the set temperature (for example, 320 ° C.) in the thermal decomposition zone C stored in the storage device 28 in the comparator 27, and then the comparison signal (second signal). Signal) V13 is led to the second arithmetic unit 29b, the arithmetic signal V15 is input to the second control signal generator 30b, and the second control signal V17 generated thereby is given to the electric motor 4 of the supply device 1, The supply amount of the waste a supplied from the supply device 1 into the pyrolysis drum 2 is adjusted.

  That is, when the temperature of the pyrolysis zone C of the pyrolysis drum 2 is higher than the set temperature, the rotation speed of the electric motor 4 starts to increase, and the supply of the waste a supplied from the supply device 1 into the pyrolysis drum 2 is performed. The amount is increased. On the other hand, when the temperature of the pyrolysis zone C of the pyrolysis drum 2 is lower than the set temperature, the rotation speed of the electric motor 4 starts to decrease, and the supply of the waste a supplied from the supply device 1 into the pyrolysis drum 2 is performed. The amount is reduced.

  Further, the temperature of the outlet air of the pyrolysis drum 2 is detected by the temperature sensor 6e of the heated air provided at the inlet of the pyrolysis drum 2, and the detection signal V4 is led to the control device 26, and the control signal V16 created there is used. It is also possible to operate the control valve 10 to control the amount of heated air introduced into the pyrolysis drum 2.

  Although the case where a plurality of, for example, four temperature sensors 6a to 6d are used has been described in the above description, the temperature sensors at the inlet of the pyrolysis drum and the evaporation zone can be omitted.

(Example)
FIG. 5 is a diagram showing the waste temperature after the introduction of the waste supply amount control based on the waste temperature, that is, the waste supply amount adjustment method according to the present invention, and FIG. 6 is the waste temperature before the introduction of the waste supply amount control based on the waste temperature. FIG.

  In the figure, arrow B indicates the waste temperature measured by the temperature sensor 6b, arrow C indicates the waste temperature measured by the temperature sensor 6c, and the hatched portion indicates the difference between the SV value (target value) and the PV value (actual value). Yes.

  In the pyrolysis drum type waste treatment apparatus, there is not a problem that there are many shaded portions, but a problem is that a large drop (a deep chain line portion (a portion indicated by an arrow P in FIG. 6)) occurs even in a short time.

  After the implementation of the present invention, as shown in FIG. 5, the fluctuation of the dust temperature in the pyrolysis drum 2 is reduced, and a stable heat treatment can be performed.

  5 and 6, arrow A indicates the waste temperature measured by the temperature sensor 6a, and arrow D indicates the waste temperature measured by the temperature sensor 6d.

It is a schematic block diagram of the waste processing apparatus which enforces the waste supply amount adjustment method which concerns on this invention. It is a distribution map which shows distribution of a waste material. It is explanatory drawing which shows the temperature change of the waste in a thermal decomposition drum. It is a schematic block diagram of the conventional waste processing apparatus. It is a diagram which shows the waste temperature after introduction of waste supply amount control by waste temperature (after introduction of the waste supply amount adjustment method which concerns on this invention). It is a diagram which shows the waste temperature before introduction of waste supply amount control by waste temperature.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Supply apparatus 2 Thermal decomposition drum 4 Electric motor 6a-6d Temperature sensor a Waste b1 Heated air c Thermal decomposition residue d Combustion component e Noncombustion component G Decomposition gas

Claims (2)

Waste is supplied into the pyrolysis drum by a supply device that is actively driven by an electric motor, and the waste is indirectly heated with heated air to generate cracked gas and pyrolysis residue, and the pyrolysis residue is combusted as a combustion component. In the waste treatment apparatus in which the cracked gas and the combustion component are burned and separated, the temperature of the waste in the pyrolysis drum is detected by a temperature sensor, and the pyrolysis drum Waste supply in a waste treatment apparatus, wherein the amount of waste supplied from the supply device into the pyrolysis drum is adjusted by controlling the electric motor when the temperature of the waste is deviated from a set temperature Quantity adjustment method. The temperature of the waste in the pyrolysis zone is detected by a temperature sensor provided in the pyrolysis zone of the pyrolysis drum, and when the temperature deviates from the set temperature, the electric motor is controlled and supplied from the supply device into the pyrolysis drum The method of adjusting a waste supply amount in a waste treatment apparatus according to claim 1, wherein the supply amount of waste to be discharged is adjusted.

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