JP2017089990A - Drying facility and its operational method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a required heat quantity per unit time constant by making a load of a dryer constant when a hot stove to which a fluidized bed combustion furnace is applied is used as a heat source of the dryer. The technical problem was to develop a new drying facility that can stabilize the state and can be operated at a low running cost, and its operation method.
By setting in advance a moisture value of a dried product P obtained by processing an object to be processed by a dryer 1, and setting a water evaporation amount per unit time from the object to be processed in the dryer 1. In addition, an operation is performed in which the amount of heat per unit time required in the dryer 1 is constant, and a moisture meter 21 for measuring the moisture value of the object to be processed is provided. A control device is provided for performing control for automatically adjusting the amount of material to be processed into the dryer 1 so that the amount of water supplied per unit time is constant.
[Selection] Figure 1

Description

  TECHNICAL FIELD The present invention relates to a drying facility such as sludge, and in particular, a drying facility using a hot blast furnace to which a fluidized bed combustion furnace using an inexpensive solid fuel such as RDF or RPF is applied as a heat source of the dryer, and an operating method thereof. It is related to.

Recently, sludge is dried and reused as fertilizer. For example, as shown in FIG. 8, a drying facility 1 'used for this purpose is a burner using sludge D or the like supplied from a sludge supply device 2' to a dryer 5 'and further using fossil fuel such as heavy oil. Drying is performed by supplying hot air of several hundred degrees from the hot air furnace 3 ′ heated by 36 a ′ and contacting the sludge D to obtain a dried product P.
And this inventor invented the method for implement | achieving the stable driving | operation of the said drying equipment, has already acquired the patent right (refer patent document 1), and also dried the paste-like substance (sludge) by drying equipment. Has been invented in a stable and continuous manner, and has already obtained a patent right (see Patent Document 2).

Furthermore, the present applicant uses the fuzzy reasoning having the newly found condition part and conclusion part to ensure that the moisture value of the dried product is stable and to prevent poor sludge dispersion and overdrying. Have been developed and a patent right has already been acquired (see Patent Document 3).
In the present invention, as shown in FIG. 9, hot air generated by a hot air furnace 3 "heated by a burner 36a" is supplied to a dryer 5 "to come into contact with the sludge D. The dried hot air (exhaust gas G1) is discharged from the exhaust port 54 ″ by the suction action of the circulation fan 71 ″, and then reaches the hot air furnace 3 ″ through the exhaust gas flow path 7 ″, where it is reheated. The present invention relates to a drying facility 1 ″ configured to be supplied again into the dryer 5 ″.

By the way, compared with heavy oil used as fuel for the burner 36a ″, waste solid fuel such as RDF or RPF is extremely low in price (1% of heavy oil) even though its calorific value is not extremely small (70% of heavy oil). / 10 or less), an example of a hot air furnace that can use such a solid fuel is a fluidized bed combustion furnace.
However, when the fluidized bed combustion furnace is applied as the hot air furnace 3 ″, there are the following problems.
That is, when the required heat quantity of the dryer 5 ″ fluctuates, that is, when the load of the hot stove 3 ″ fluctuates, it is possible to adjust the input amount of the solid fuel F such as RDF, but the solid fuel F is a liquid fuel. Unlike gas fuel and gas fuel, not only does it take time to put it into the hot stove 3 ″, but it also takes time to release heat from self-combustion.
In order to overcome such a problem, more complicated control is required when the fluidized bed combustion furnace is used as the hot blast furnace 3 '' in the drying facility 1 '' than when the burner 36a '' is used.

Therefore, the present applicant has determined that the dried product temperature and the dried product temperature change, the dryer inlet hot air temperature, the stirring blade current value, the dryer outlet hot air temperature, the opening degree of the exhaust damper provided in the exhaust gas flow path, and the dryer By performing fuzzy inference with one or more of the workpiece inputs as the condition part and the hot air temperature set value at the outlet of the dryer and / or the workpiece input amount into the dryer as the conclusion part An operation method for performing fuzzy control for reducing load fluctuations in a dryer and a hot stove has been developed and has already been applied for a patent (see Patent Document 4).
According to this invention, when a hot stove to which a fluidized bed combustion furnace is applied is used as a heat source of a dryer, the load variation of the dryer is suppressed and the amount and temperature of the exhaust gas are stabilized. As a result, the hot stove By stabilizing the temperature, it became possible to stably perform a drying operation with reduced running costs.

Furthermore, the present applicant, when using a hot stove to which a fluidized bed combustion furnace is applied as a heat source for a dryer, prevents excessive self-combustion of solid fuel and stabilizes the temperature of the hot stove, thereby reducing the running cost. A new drying facility capable of stably performing a drying operation with reduced pressure and an operating method thereof have been developed and have already been filed for a patent (see Patent Document 5).
According to the present invention, when the hot stove to which the fluidized bed combustion furnace is applied is used as a heat source of the dryer, the excessive self-combustion of the solid fuel is prevented and the temperature of the hot stove is stabilized. It has become possible to stably carry out the drying operation with reduced costs.

And since then, the present applicant has continued to develop a drying facility using a hot air furnace to which the above fluidized bed combustion furnace is applied as a heat source for the dryer, in order to solve the following new problems: The development of technology has started.
In other words, RPF (Refuse Paper & Plastic Fuel) and RDF (Refuse Derived Fuel), which are solidified fuels used as fuel for hot stove furnaces, vary greatly in calorific value and moisture content when they are obtained from different suppliers. In contrast, even when they are obtained from the same supplier, the variation in the calorific value and the water content is large, and such a variation cannot be avoided because the raw material is waste.

On the other hand, in drying equipment, it is common to procure solid waste fuel from multiple suppliers. The solid waste fuel is fed using a charging device installed in parallel to the hot stove. Before being carried out, a form in which the components are individually fed into the hot stove without mixing is employed.
For this reason, the control of the state of waste solid fuel input to the hot stove is complicated and frequently set and changed, and if part of it is performed manually, mistakes are likely to occur. The dry state of the processed product will not be as desired.

  Also, with existing drying equipment, if the temperature in the fluidized chamber in the fluidized bed combustion furnace as a hot air furnace rises too much, the metal material that is a component of the fluidized bed combustion furnace will melt, so this should be avoided. Water is sprayed into the fluid chamber. At this time, since the RPF and RDF, which are solid waste fuels, contain a relatively large amount of moisture, the amount of moisture present in the fluidized chamber becomes excessive due to watering, causing a temperature drop more than necessary. Sometimes it happened.

Furthermore, in the existing drying equipment, when the temperature of the fluidized bed (fluidized sand) formed in the fluidized chamber in the fluidized bed combustion furnace as a hot air furnace falls below a predetermined value, fuel oil is supplied from the auxiliary burner into the fluidized bed. Then, this is combusted and the temperature of the fluidized bed is increased to a predetermined value, so that the temperature of the hot air (dry gas) supplied to the dryer is controlled to a predetermined value.
For this reason, the use of expensive fuel oil cannot be ruled out, which has been a factor that hinders the reduction of the running cost of the drying equipment.

Japanese Patent No. 2981271 Japanese Patent No. 3326502 Japanese Patent No. 5410218 Japanese Patent Application No. 2014-198055 Japanese Patent Application No. 2014-198150

  The present invention has been made in view of such a background, and when a hot blast furnace to which a fluidized bed combustion furnace is applied is used as a heat source of the dryer, the load of the dryer is made constant so that the unit time is reduced. The technical challenge is to develop a new drying facility that can stabilize the combustion state of the hot stove and, as a result, stabilize the combustion condition of the hot stove, and to operate at a low running cost, and its operating method. It is.

  That is, the drying facility according to claim 1 has a dryer connected to a processing object supply device at its inlet, and a hot air furnace to which a fluidized bed combustion furnace is applied at its hot air inlet. In the drying equipment having the take-out conveyor facing the discharge port, the drying equipment sets in advance the moisture value of the dried product obtained by processing the workpiece by the dryer, and the workpiece in the dryer By setting the amount of water evaporation per unit time from the operation, the operation to make the amount of heat per unit time required in the dryer constant is performed, and the drying equipment further Control for automatically adjusting the amount of material to be processed into the dryer so that the amount of moisture supplied per unit time into the dryer is constant, as well as a moisture meter for measuring the value Equipment is a tool It is intended that comprised as said being.

  In addition to the above requirements, the drying facility according to claim 2 uses a water-containing solid waste fuel as a fuel for the hot stove, and includes a moisture meter for measuring the moisture value of the fuel. And calculating the amount of heat per unit time necessary for drying the object to be processed to a desired moisture value based on the amount of water evaporated from the object to be processed set in the dryer. Means, a conveyor for feeding fuel into the hot stove, and means for measuring the weight and moisture value of the fuel located on the conveyor, and the amount of fuel fed into the hot stove per unit time , And a control device for performing a control for automatically adjusting the amount of fuel input to the hot stove to be constant is provided.

  Furthermore, in addition to the above requirements, the drying facility according to claim 3 includes a plurality of means for feeding fuel into the hot stove, and means for measuring the weight and moisture values of the fuel located on the conveyor. It is characterized by being prepared.

  Furthermore, in addition to the requirements described in claim 2 or 3, the drying facility according to claim 4 is provided with means for sprinkling water into the hot stove, and the amount of fuel per unit time input into the hot stove. Means for calculating the amount of moisture located in the furnace and means for adjusting the amount of water sprayed into the hot stove according to the amount of moisture in the hot stove are provided.

  Further, according to the fifth aspect of the present invention, the drying equipment operating method is such that a dryer is connected to a processing object supply device at its inlet, and a hot air furnace to which a fluidized bed combustion furnace is applied is connected to the hot air inlet. In addition, in the operation method of the drying equipment with the take-out conveyor facing the discharge port, the moisture value of the dried product obtained by processing the object to be processed by the dryer is set in advance, and the object to be processed in the dryer By setting the amount of moisture evaporated per unit time from the product, the operation is performed to keep the amount of heat per unit time required in the dryer constant, and the moisture value of the object to be treated is measured during the operation. At the same time, the amount of moisture supplied to the dryer is automatically adjusted by controlling the amount of the material to be processed per unit time into the dryer.

  Furthermore, in addition to the requirement of claim 5, the operating method of the drying facility according to claim 6 uses a water-containing waste solidified fuel as the fuel for the hot stove, and measures the moisture value of the fuel. The amount of heat per unit time required for drying the object to be processed to a desired moisture value is calculated based on the amount of water evaporated from the object to be processed, which is set in the dryer. Measure the weight and moisture value of the fuel located on the conveyor for fuel injection into the furnace, and also set the fuel input amount per unit time into the hot stove to control the fuel input into the hot stove Thus, the amount of fuel input to the hot stove is automatically adjusted so that the amount of heat supplied to the dryer becomes constant.

  Furthermore, in addition to the requirements of claim 5 or 6, the operating method of the drying facility according to claim 7 is a method in which fuel is supplied to the combustion furnace by a plurality of conveyors, and the fuel is located on each conveyor. It is characterized by measuring the weight and moisture value of the water.

Furthermore, in addition to the requirements described in claim 6 or 7, the operation method of the drying facility according to claim 8 calculates the amount of water located in the combustion furnace from the amount of fuel injected into the combustion furnace per unit time. Then, the amount of water sprayed into the drying furnace is adjusted according to the amount of water in the combustion furnace.
The above problems can be solved by using the configuration of the invention described in each of the claims as a means.

First, according to the first or fifth aspect of the present invention, since the amount of water evaporation per unit time from the object to be processed in the dryer is constant, the operation of the dryer can be stabilized.
In addition, since the amount of heat per unit time required in the dryer is constant, the temperature of the hot air (dry gas) supplied to the dryer can be kept constant at all times, and the hot air furnace that is the source of hot air Operation can be made stable.
That is, according to the invention described in claim 1 or 5, among the components of the drying equipment, particularly the dryer and the hot air furnace, which are the main components, can be stably operated. Will be realized.

According to the invention described in claim 2 or 6, the amount of waste solid fuel necessary for generating this amount of heat based on the amount of heat per unit time required for drying the object to be processed in the dryer is not excessive or insufficient. It will be supplied to the hot stove.
That is, since hot air is supplied from a hot stove that is operated so that a constant amount of heat is always obtained with respect to a dryer having a constant amount of water evaporation, the dryer and the hot stove are operated stably. Therefore, stabilization of the entire drying equipment is realized.
Incidentally, in the past, when the required heat quantity of the dryer fluctuates, that is, when the load of the hot stove fluctuates, when the solid fuel input amount is adjusted by PID control, the solid fuel is different from the liquid fuel in the hot stove. In addition to the time it takes to put in, it takes time to release the heat due to self-combustion, so the amount of solid fuel supply may become excessive, According to these inventions, such a situation can be avoided.

Furthermore, according to the invention described in claim 3 or 7, it is possible to handle a plurality of types of solid waste fuel at the same time, and to put waste solid fuels having different properties into the hot stove respectively in an appropriate amount. Therefore, it can be used at a ratio that takes into consideration the availability and economics of solid waste fuel.
As a result, the drying facility can be suitably operated in a state in accordance with the purpose, such as emphasizing stability and emphasizing economy.

Furthermore, according to the invention described in claim 4 or 8, the amount of water located in the hot stove can be set to a suitable state, and the temperature in the fluid chamber can be prevented from fluctuating excessively.
In addition, since the temperature in the fluid chamber can be prevented from excessively decreasing, the conventional fuel supply by the auxiliary burner is not required, and the use of fossil fuel is only low at the start-up ignition. Driving at a running cost can be performed.

It is a skeleton figure showing drying equipment. It is the front view and side view which show a dryer. It is a side view which shows the hot stove to which the fluidized bed combustion furnace was applied. It is a flowchart which shows the flow of control of the sludge injection amount to a dryer. It is a flowchart which shows the flow of control of the amount of solid fuel input to a hot stove. It is a flowchart which shows the flow of control of the amount of solid fuel input to a hot stove. It is a flowchart which shows the flow of control of the watering amount to a hot stove. It is a skeleton figure which shows the existing drying equipment. It is a skeleton diagram showing the existing drying equipment which recirculates exhaust gas by reheating.

  The best mode of the drying equipment and the operation method of the present invention is as shown in the following examples. However, it is possible to appropriately modify the examples within the scope of the technical idea of the present invention. .

Hereinafter, an example of the drying facility of the present invention will be described based on the drawings, and the operation method of the drying facility of the present invention will be described together with the operating state of the facility.
FIG. 1 schematically shows a drying facility 1, which has a sludge supply device 2 facing a drier 5 at its inlet 51 and a hot stove 3 connected to its hot air inlet 53. Further, the take-out conveyor 6 faces the discharge port 52.
In addition, the hot air furnace 3 is a fluidized bed combustion furnace, and between the dryer 5 and the hot air furnace 3 so that the exhaust gas G1 discharged from the dryer 5 can be deodorized. An exhaust gas flow path 7 is provided.
Further, although not shown, the drying facility 1 includes a control unit for controlling the components of the drying facility 1 such as the hot stove 3 and the dryer 5.

Hereinafter, various members constituting the drying facility 1 will be described in detail.
First, the sludge supply device 2 will be described. This device includes a screw conveyor 2a driven by an inverter motor M2 at the bottom of the supply hopper 20, and the object to be dried such as sludge D accommodated in the supply hopper 20 is screwed. An appropriate amount is discharged according to the rotational speed of the conveyor 2a (inverter motor M2).
The next stage of the screw conveyor 2a includes a relay conveyor 2b to which a belt-type weighing conveyor is applied as an example, and a discharge portion of the relay conveyor 2b is installed so as to face the charging port 51 in the dryer 5.
In addition, the moisture meter 21 for measuring the moisture value of the sludge D which is a to-be-processed object located on the relay conveyor 2b is provided.

Next, the hot air furnace 3 will be described. This is a thing to which a fluidized bed combustion furnace is applied as shown in FIG. 3, and the solid fuel F is self-combusted while flowing together with the fluidized sand S in the fluidizing chamber 31. Thus, hot air (dry gas G) is generated.
As shown in FIG. 1 and FIG. 3 as an example, the hot stove 3 has a hollow tower-like overall shape, and is connected to a fluid chamber 31 that is a substantial combustion space and above and below the fluid chamber 31. The exhaust chamber 32 and the fluidized air blowing chamber 33, the air diffuser 34, and the charging device 35 for supplying the solid fuel F into the fluidized chamber 31 are provided as main members.
An air supply port 33 a is formed in the fluidized air blowing chamber 33, an air supply port 31 a is formed in the flow chamber 31, and an exhaust port 32 a, an input port 32 b and an air supply port 32 c are formed in the exhaust chamber 32.
Further, a water spray nozzle 37 directed downward is provided at an upper portion of the flow chamber 31 in the exhaust chamber 32, and a pipe line provided with a water spray valve 37 a is connected to the water spray nozzle 37.
Further, a start furnace 36 is connected to the air supply port 33a. The start furnace 36 is provided with a start burner 36a and a flow blower 36b. An air flow meter 36c is provided in a pipe line connecting the start furnace 36 and the fluid blower 36b.

The hot stove 3 configured in this manner forms a fluidized bed of fluidized sand S above the diffuser pipe 34 (fluid chamber 31) by hot air supplied from the air supply port 33a, and in this state the inlet port By supplying the solid fuel F from 32b, the solid fuel F is sent into the fluidized bed (fluid chamber 31) and is self-combusted here to generate hot air. This hot air is discharged from the exhaust port 32a to the outside. To be released.
The start burner 36a is ignited only when the hot stove 3 is started up, and after the hot stove 3 shifts to the steady operation, only the air blow by the fluid blower 36b is performed.

The feeding device 35 includes a screw conveyor 35a driven by an inverter motor M3 provided at the bottom of a box-shaped container, and the solid fuel F stored in the container is rotated by the screw conveyor 35a (inverter motor M3). An appropriate amount is discharged according to the number.
The next stage of the screw conveyor 35a includes a relay conveyor 35b to which a belt-type weighing conveyor is applied as an example, and the next stage of the relay conveyor 35b includes an input conveyor 35c to which a screw conveyor is applied as an example. It is done. And the discharge part of this input conveyor 35c is connected to the input port 32b in the hot stove 3.
A moisture meter 35d for measuring the moisture value of the solid fuel F located on the relay conveyor 35b is provided.

  In this embodiment, the charging device 35 has two systems of a charging device 351 and a charging device 352 arranged in parallel. By adopting such a configuration, for example, a plurality of types of solid waste fuels are provided. Can be handled simultaneously as the solid fuels F1 and F2. In addition, waste solid fuels F1 and F2 having different properties can be fed into the hot stove 3 in appropriate amounts, so that they can be used at a ratio that takes into account the availability and economics of solid waste fuel. It becomes. Of course, three or more such charging devices 35 may be provided, or only one system may be provided.

Next, the dryer 5 will be described. As an example, a rotary drum dryer is applied to the dryer 5, and four support rollers 57 are arranged with respect to the base B as shown in FIG. A cylindrical drum 50 is placed on the support roller 57 and provided.
A chain 59 is wound around the drum 50 and the output shaft of the motor M51, and the drum 50 is rotated by the motor M51. Further, both ends of the drum 50 are closed with the boundary portions sealed by the lid members 50a and 50b.
A shaft 55a provided so as to pass through the vicinity of the center of the drum 50 is rotationally driven by a motor M52, and a stirring blade 55 is provided on the shaft 55a.
The lid member 50a is formed with a hot air blowing port 53, and a charging port 51 is formed in a charging mechanism provided to penetrate the lid member 50a.
Further, a discharge port 52 and an exhaust port 54 are formed in the lid member 50b.

  Next, the take-out conveyor 6 will be described. As an example, the take-out conveyor 6 includes a screw conveyor driven by an inverter motor M6 at the bottom of the U-shaped trough, and the dried product P dropped into the U-shaped trough is screw conveyor ( The inverter motor M6) is configured to sequentially discharge with rotation. Of course, other conveyors such as a belt conveyor can be applied as the take-out conveyor 6.

The members constituting the drying facility 1 of the present invention are configured as described above as an example, and the hot stove 3 and the dryer 5 are, as shown in FIG. 1, a hot air passage 4 and an exhaust gas passage. 7 is connected.
First, the exhaust port 32a in the hot air furnace 3 and the hot air blowing port 53 in the dryer 5 are connected by the hot air channel 4, and the hot air channel 4 is provided with an air supply damper 41.
The hot air flow path 4 is branched so as to connect the exhaust port 32a and a heat exchanger 78 described later, and this branch path is defined as an exhaust flow path 4B. The exhaust passage 4B is provided with a valve 43.

On the other hand, the exhaust port 54 in the dryer 5 and the air supply ports 31a and 32c in the hot stove 3 are connected by the exhaust gas flow path 7. The exhaust gas flow path 7 includes a dust collector 72 and An exhaust damper 73 is provided.
The exhaust damper 73 is, for example, a device for opening and closing a blade plate by rotation of a control motor to increase or decrease or close the flow rate of the passing gas, and such a configuration is another damper shown in the present specification. The same applies to.
Further, a circulation fan 71 and a heat exchanger 78 are provided in the next stage of the exhaust damper 73. The next stage of the heat exchanger 78 is branched into two paths, and a flow rate adjusting valve 78a is provided in each flow path. Yes.

In addition to the sensors already described, the drying facility 1 of the present invention includes the following sensors.
First, between the air supply damper 41 in the hot air flow path 4 and the exhaust port 32 a in the hot air furnace 3, the temperature sensor 42 and the probe of the air meter 44 are arranged inside.
Further, this is arranged so that the probe of the dry product moisture sensor 60 is located inside the U-shaped trough of the take-out conveyor 6.
Further, a temperature sensor 38 is installed so that the probe is located inside the flow chamber 31 or the exhaust chamber 32 in the hot stove 3.
The output signals of these sensors and the weighing conveyor are sent to the control unit (not shown).

The drying facility 1 of the present invention has the above-described configuration as an example. The operating state of this facility will be described below, and the operation method of the drying facility of the present invention will be described.
In the present invention, the control of the amount of sludge D input to the dryer 1 in the drying facility 1, the control of the amount of solid fuel F input to the hot stove 3, and the control of the amount of water sprayed to the hot stove 3 are linked. Yes, each of these controls will be described sequentially.
In the following description, RPF and RDF (hereinafter referred to as solid fuel F), which are hydrous waste solidified fuels, which are so-called biomass resources, are used as fuels for the hot stove 3 as the objects to be processed. The sludge D is dried to obtain a dried product P.
When the drying equipment 1 is started, the starter burner 36a is first ignited, the hot stove 3 is started up, and when the drying gas G having a sufficient temperature is obtained, the dryer 5 is processed. The sludge D which is a thing is thrown in.

(1) Control of Sludge Input to Dryer First, when the amount of sludge D input to the dryer 1 is controlled, processing according to the flow shown in FIG. 4 is performed.
First, the moisture value (target value) of the dried product P is set (step S11). In this embodiment, as an example, 10% W.W. B. It was.

  Next, the water evaporation amount per unit time from the sludge D (object to be processed) in the dryer 1 is set (step S12). In this example, it was 1944 kg / h as an example.

  Next, the moisture value of the sludge D is measured. As an example, the moisture value of the sludge D on the relay conveyor 2b is measured by the moisture meter 21 (step S13). In this embodiment, as an example, the average value of the measurement results is 80% W.W. B. It was.

  Next, the input amount of the sludge D is calculated so that the water evaporation amount per unit time (1944 kg / h) from the sludge D set in step S12 is obtained (step S14). In this embodiment, it becomes 2499.43 kg / h as an example.

  Next, the input amount of sludge D calculated in step S14 is set (step S15).

Then, the amount of sludge D input to the dryer 1 is PID controlled based on such settings (step S16), so that the amount of water supplied per unit time into the dryer 1 is constant. The drive frequency of the inverter motor M2 is automatically adjusted.
In addition, the weight of the sludge D is always measured by the relay conveyor 2b to which the belt type weighing conveyor is applied.

As described above, the control of the amount of sludge D input to the dryer 1 of the present invention is such that the amount of water evaporation per unit time from the sludge D in the dryer 1 is constant. This also means that the amount of heat required per unit time is constant.
For this reason, the amount of heat generated in the hot stove 3 and supplied to the dryer 1 is also constant, and the amount of water evaporation per unit time (1944 kg / h) from the sludge D set in step S12 is set as follows. On the basis of this, the theoretical drying heat quantity is calculated (step S17). In this embodiment, as an example, it is 5106686 kJ / h.

  Next, the equipment thermal efficiency is set in consideration of the constituent equipment of the drying equipment 1 (step S18). In this embodiment, it is 0.6 as an example.

  Next, the heat required for drying is calculated from the heat required for theoretical drying and the equipment thermal efficiency (step S19). In this embodiment, it is 8511143 kJ / h as an example.

(2) Control of Solid Fuel Input to Hot Air Furnace In controlling the input of solid fuel F to the hot air furnace 3, processing according to the flow shown in FIGS. 5 and 6 is performed.
First, the input amount of the solid fuel F1 is set (step S21). In this example, it was set to 300 kg / h as an example.

Based on such settings, PID control is performed so that the amount of solid fuel F1 charged into the hot stove 3 is constant (step S22), and the drive frequency of the inverter motor M3 in the charging device 351 is automatically set. Adjusted.
The weight of the solid fuel F1 is constantly measured by a relay conveyor 35b to which a belt type weighing conveyor is applied.

  Next, the moisture value of the solid fuel F1 is measured. As an example of the charging device 351, the moisture value of the solid fuel F1 located on the relay conveyor 35b is measured by the moisture meter 35d (step S23). In this example, as an example, the average value of the measurement results is 50% W.W. B. It was.

  Next, the calorific value of the solid fuel F1 is set manually (step S24). In this embodiment, the heat generation amount is 27209 kJ / kg as an example.

Next, the dry matter amount, water amount W1 and generated heat amount of the solid fuel F1 are calculated using the set values and measured values (step S25). In this embodiment, 150 kg / h, 150 kg / h, 4081350 kJ / h.
Here, the dry matter amount means the weight of the solid component of the solid fuel F1, and here means the weight supplied to the hot stove 3 per unit time.
The amount of water means the weight of water contained in the solid fuel F1, and here means the weight supplied to the hot stove 3 per unit time.

  Next, the calorific value of the solid fuel F2 is set manually (step S31). In this embodiment, 20930 kJ / kg is set as an example.

  Next, the moisture value of the solid fuel F2 is measured. As an example of the charging device 352, the moisture value of the solid fuel F2 located on the relay conveyor 35b is measured by the moisture meter 35d (step S32). In this embodiment, as an example, the average value of the measurement results is 10% W.W. B. It was.

  Next, the supplied heat quantity Q2 of the solid fuel F2 is calculated, and Q2 is calculated from the difference between the heat quantity Q ′ required for drying calculated in S19 and the generated heat quantity Q1 of the solid fuel F1 calculated in S25 ( Step S33). In this example, it was 4429793 kJ / h as an example.

  Next, the input amount of solid fuel F2, the amount of dry matter, and the amount of water W2 are calculated (step S34). .

Next, the input amount of the solid fuel F2 is set based on this calculation result (step S35), and the PID is set so that the input amount of the solid fuel F2 to the hot stove 3 becomes constant based on such setting. Control is performed (step S36), and the drive frequency of the inverter motor M3 in the input device 352 is automatically adjusted.
The weight of the solid fuel F2 is constantly measured by a relay conveyor 35b to which a belt type weighing conveyor is applied.

(3) Control of the amount of water sprayed to the hot stove In controlling the amount of water sprayed to the hot stove 3, processing according to the flow shown in FIG. 7 is performed.
First, the total water content W to be charged into the hot stove 3 is set (step S41), and in this embodiment, it is set to 600 kg / h as an example.

  Next, the water spray amount W37 from the water spray nozzle 37 is calculated using the water amount W1 calculated in S25 and the water amount W1 calculated in S34 (W37 = W− (W1 + W2) (step S42). In this example, it was 426.48 kg / h as an example.

  Next, the sprinkling amount W37 is set based on this calculation result, and the opening degree of the sprinkling valve 37a is controlled based on such setting (step S45).

  According to the invention, the amount of moisture located in the hot stove 3 can be in a suitable state, and the temperature in the flow chamber 31 can be prevented from fluctuating excessively. As a safety measure when the amount of water located in the hot stove 3 becomes excessive due to such trouble, a flow for starting the auxiliary burner 39 is added as enclosed by a broken line in FIG. Also good.

As described above, according to the present invention, the amount of water evaporation per unit time from the object to be processed in the dryer 5 is constant, so that the operation of the dryer 5 can be stabilized.
Further, since the amount of heat per unit time required in the dryer 5 is constant, the temperature of the hot air (dry gas G) supplied to the dryer 5 can be kept constant at all times, which is a hot air supply source. The operation of the hot stove 3 can be made stable. That is, among the components of the drying facility 1, particularly the dryer 5 and the hot stove 3 that are main components can be stably operated, so that the entire drying facility 1 is stabilized.

Further, according to the present invention, based on the amount of heat per unit time required for drying the object to be processed in the dryer 5, the waste solid fuel F necessary for generating this amount of heat is supplied to the hot stove 3 without excess or deficiency. Will be supplied. That is, since the hot air (dry gas G) is supplied from the hot air furnace 3 operated so as to obtain a constant amount of heat to the dryer 5 that always has a constant amount of water evaporation, these dryers 5 and The hot stove 3 can be operated stably, and stabilization of the drying equipment 1 as a whole is realized.
Incidentally, conventionally, when the required heat quantity of the dryer 5 fluctuates, that is, when the load of the hot stove 3 fluctuates, the solid fuel F is different from the liquid fuel when the input amount of the solid fuel F is adjusted by PID control or the like. Thus, not only does it take time to put it into the hot stove 3, but it also takes time until the heat generated by self-combustion is released, so the supply amount of the solid fuel F becomes excessive. However, according to these inventions, such a situation can be avoided.

  Furthermore, according to the present invention, it is possible to handle a plurality of types of solid fuel F (waste solid fuel) at the same time, and it is possible to put solid fuel F having different properties into the hot stove 3 in an appropriate amount. Therefore, it can be used at a ratio that takes into account the availability and economics of the solid fuel F. As a result, the drying facility 1 can be suitably operated in a state in accordance with the purpose, such as emphasis on stability and economy.

In addition to the control described above, the drying facility 1 also performs the following control.
First, the rotational speed of the drum 50 of the dryer 5 and the rotational speed of the stirring blade 55 are controlled by measuring the moisture value of the dried product P with the moisture sensor 60 of the dried product and according to the deviation between this value and the target moisture value. Is.
Control is performed to adjust the amount of air distributed to the dryer 5 and the heat exchanger 78 in accordance with the deviation between the measured value of the anemometer 44 provided immediately after the exhaust port 32a of the hot stove 3 and the target wind speed value.
Furthermore, since the flowing air in the hot air furnace 3 becomes a wind necessary for flowing sand, an air flow meter 36c is installed between the flow blower 36b and the start furnace 36, and the air volume is adjusted based on the detected value. Control is performed.
Furthermore, the air volume of the dried gas G1 supplied to the air supply ports 31a and 32c in the hot stove 3 is also appropriately distributed to the flow chamber 31 and the exhaust chamber 32 based on the detected value and the set value of the air flow meter. Control for adjusting the opening degree of the flow rate adjusting valve 78a provided in each of the branched flow paths is performed.

1 Drying equipment

2 Sludge supply device 20 Supply hopper 2a Screw conveyor 2b Relay conveyor 21 Moisture meter

3 Hot Air Furnace 31 Flow Chamber 31a Air Supply Port 32 Exhaust Chamber 32a Exhaust Port 32b Input Port 32c Air Supply Port 33 Fluid Air Blowing Chamber 33a Air Supply Port 34 Aeration Pipe 35 Input Device 351 Input Device 352 Input Device 35a Screw Conveyor 35b Relay Conveyor 35c Input conveyor 35d Moisture meter 36 Start furnace 36a Start burner (burner)
36b Flow blower 36c Air flow meter

37 Watering nozzle 37a Watering valve 38 Temperature sensor 39 Auxiliary burner

4 Hot air flow path 4B Exhaust flow path 41 Supply damper 42 Temperature sensor 43 Valve 44 Anemometer

5 Dryer 50 Drum 50a Lid Member 50b Lid Member 51 Input Port 52 Discharge Port 53 Hot Air Blow Port 54 Exhaust Port 55 Stirring Blade 55a Shaft 57 Support Roller 59 Chain 6 Takeout Conveyor 60 Dry Product Moisture Sensor 7 Exhaust Gas Flow Channel 71 Circulation Fan 72 Dust collector 73 Exhaust damper 78 Heat exchanger 78a Flow control valve

B Base D Sludge F Solid fuel F1 Solid fuel F2 Solid fuel

G Dry gas G1 Exhaust gas M2 Inverter motor M3 Inverter motor M51 Motor M52 Motor M6 Inverter motor P Dry product S Fluid sand

Claims (8)

Connect the processing equipment supply device to the inlet of the dryer, connect the hot air furnace to which the fluidized bed combustion furnace is applied to the hot air inlet, and the take-out conveyor to the outlet. In the drying equipment consisting of
This drying equipment sets the moisture value of the dried product obtained by processing the object to be processed by the dryer in advance, and sets the water evaporation amount per unit time from the object to be processed in the dryer. An operation is performed in which the amount of heat per unit time required in the dryer is constant,
Further, the drying equipment includes a moisture meter for measuring the moisture value of the object to be treated, and inputs the object to be treated into the dryer so that the amount of moisture supplied per unit time into the dryer is constant. A drying facility comprising a control device for performing control for automatically adjusting the amount.
A hydrous waste solidified fuel is used as the fuel for the hot stove,
In addition to having a moisture meter to measure the moisture content of this fuel,
Means for calculating the amount of heat per unit time required for drying the object to be processed to a desired moisture value based on the amount of water evaporated from the object to be processed set in the dryer;
A conveyor for charging fuel into the hot stove, and means for measuring the weight and moisture value of the fuel located on the conveyor,
In addition, a control device is provided for performing a control for automatically adjusting the amount of fuel to be supplied to the hot stove so that the amount of fuel to be supplied per unit time is set and the amount of fuel to be supplied to the hot stove is constant. The drying equipment according to claim 1.
3. A conveyor for supplying fuel to the hot stove and a plurality of means for measuring the weight and moisture value of the fuel located on the conveyor are provided. Drying equipment.
Means for watering the hot stove;
Means for calculating the amount of water located in the hot stove from the amount of fuel injected into the hot stove per unit time;
4. The drying facility according to claim 2, further comprising means for adjusting the amount of water sprayed into the hot stove according to the amount of water in the hot stove.
Connect the processing equipment supply device to the inlet of the dryer, connect the hot air furnace to which the fluidized bed combustion furnace is applied to the hot air inlet, and the take-out conveyor to the outlet. In the operation method of the drying equipment comprising:
It is necessary in the dryer by setting in advance the moisture value of the dried product obtained by processing the object to be processed by the dryer and setting the amount of moisture evaporation per unit time from the object to be processed in the dryer. The operation is to keep the amount of heat per unit time constant,
Furthermore, the moisture value of the object to be treated is measured during operation, and the amount of moisture supplied into the dryer is automatically adjusted by controlling the amount of the object to be treated per unit time to the dryer. The operation method of the drying equipment characterized by this.
Using water-containing waste solidified fuel as fuel in the hot stove,
While measuring the moisture content of this fuel,
Based on the water evaporation per unit time from the object to be processed set in the dryer, the amount of heat per unit time required to dry the object to be processed to a desired moisture value is calculated,
While measuring the weight and moisture value of the fuel located on the conveyor for feeding the fuel into the hot stove,
In addition, by setting the amount of fuel input to the hot stove per unit time and controlling the amount of fuel input to the hot stove,
To keep the heat supply to the dryer constant,
6. The method of operating a drying facility according to claim 5, wherein the amount of fuel input to the hot stove is automatically adjusted.
The method of operating a drying facility according to claim 5 or 6, wherein the fuel is fed into the combustion furnace by a plurality of conveyors, and the weight and moisture value of the fuel located on each conveyor are measured.
  The amount of water located in the combustion furnace is calculated from the amount of fuel injected into the combustion furnace per unit time, and the amount of water sprayed into the drying furnace is adjusted according to the amount of water in the combustion furnace. A method for operating a drying facility according to claim 6 or 7.

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