JP6732435B2 - Drying facility and its operating method - Google Patents

Description

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

Recently, sludge is dried and reused as fertilizer. As an example of the drying equipment 1'used for this purpose, as shown in FIG. 8, sludge D or the like is put into a dryer 5'from a sludge supply device 2', and a burner using fossil fuel such as heavy oil is used. Drying P is obtained by supplying hot air of several hundred degrees from the hot air oven 3'heated by 36a' to bring it into contact with the sludge D for drying.
The applicant of the present invention has invented a method for realizing stable operation of the drying equipment and has already obtained a patent right (see Patent Document 1). Further, drying the paste-like substance (sludge) by the drying equipment. Has invented a method that enables stable and continuous operation, and has already obtained a patent right (see Patent Document 2).

Further, the present applicant uses the fuzzy inference having the newly found condition part and conclusion part to ensure that the moisture value of the dried product is stable, and that sludge dispersion failure and overdrying are prevented. In addition to the above, a new method of operating a drying facility that can reduce the initial cost has been developed and a patent right has already been obtained (see Patent Document 3).
As shown in FIG. 9, the present invention supplies hot air generated by a hot-air stove 3″ heated by a burner 36a″ to a dryer 5″ so as to contact 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″, then reaches the hot air stove 3″ through the exhaust gas passage 7″, and is reheated there. After that, the present invention relates to the drying equipment 1″ configured to be supplied again into the dryer 5″.

By the way, compared with the heavy oil used as the fuel for the burner 36a″, the waste solid fuel such as RDF or RPF has an extremely low calorific value (70% of the heavy oil), but the price is very low (1% of the heavy oil). /10 or less), and a hot-air stove capable of using such a solid fuel is, for example, a fluidized bed combustion furnace.
However, when the fluidized bed combustion furnace was applied as the hot blast stove 3″, there were the following problems.
That is, when the required heat amount of the dryer 5″ changes, that is, when the load of the hot stove 3″ changes, it is possible to adjust the input amount of the solid fuel F such as RDF. Unlike gas fuel and gas fuel, it takes not only time to put into the hot blast stove 3″, but also time to release heat due to self-combustion.
In order to overcome such a problem, when a fluidized bed combustion furnace is used as the hot air stove 3″ in the drying equipment 1″, more complicated control is required as compared with the case where the burner 36a″ is used.

Therefore, the applicant of the present invention has proposed that the dry product temperature and the change in the dry product temperature, the dryer hot air temperature, the stirring blade current value, the dryer hot air temperature, the opening of the exhaust damper provided in the exhaust gas flow path, and the dryer By performing fuzzy inference with any one or more of the input amount of the processed material as the condition part and the conclusion part as the hot air temperature set value at the dryer outlet and/or the input amount of the processed material to the dryer Has developed a fuzzy control operation method for reducing load fluctuations of a dryer and a hot stove, and has already applied for a patent (see Patent Document 4).
According to the present invention, when the hot air stove to which the fluidized bed combustion furnace is applied is used as the heat source of the dryer, the load fluctuation of the dryer is suppressed to stabilize the amount and temperature of the exhaust gas. As a result, the hot air stove By stabilizing the temperature of, it became possible to stably perform the drying operation with reduced running cost.

Furthermore, when the hot-air stove to which the fluidized bed combustion furnace is applied is used as the heat source of the dryer, the present applicant prevents excessive self-combustion of solid fuel and stabilizes the temperature of the hot-air stove, thereby reducing the running cost. We have developed a new drying equipment and a method of operating the drying equipment that can carry out a stable drying operation with reduced temperature, and have already applied for a patent (see Patent Document 5).
And according to the present invention, when the hot air stove to which the fluidized bed combustion furnace is applied is used as the heat source of the dryer, by preventing excessive self-combustion of the solid fuel and stabilizing the temperature of the hot air stove, the running It has become possible to perform a stable drying operation at low cost.

Then, the applicant has continued to develop the drying equipment using the hot air stove to which the fluidized bed combustion furnace as described above is applied as the heat source of the dryer, in order to solve the following new problems. Came to undertake the technological development of.
In other words, RPF (Refuse Paper & Plastic Fuel) and RDF (Refuse Derived Fuel), which are solid waste fuels used as fuel for hot blast stoves, have large fluctuations in calorific value and water content when obtained from different sources. In addition, even if they are obtained from the same supplier, the variations in the calorific value and the water content are large, and it is the fact that such variations cannot be avoided because the raw materials are waste.

On the other hand, in the drying equipment, it is common to procure waste solidified fuel from multiple sources, and the waste solidified fuel is input using a charging device installed in parallel with the hot blast stove. Before mixing, a form is adopted in which they are individually charged into the hot-blast stove without mixing.
For this reason, the control of the injection state of the solid waste fuel into the hot blast stove becomes complicated with many settings and changes, and it is easy to make an error if a part of it is manually operated, and as a result, the amount of waste in the dryer is reduced. The dry state of the processed product will not be the desired one.

In addition, in the existing drying equipment, if the temperature in the fluidization chamber in the fluidized bed combustion furnace as a hot-air stove rises too much, the metal material that is a component of the fluidized bed combustion furnace will melt. Water is sprinkled in the fluid chamber. At this time, since the waste solidified fuels RPF and RDF contain a relatively large amount of water, the amount of water present in the fluidized chamber becomes excessive due to water sprinkling, causing a temperature drop more than necessary. It was sometimes lost.

Furthermore, in the existing drying equipment, when the temperature of the fluidized bed (fluid sand) formed in the fluidized chamber in the fluidized bed combustion furnace as a hot-air stove falls below a predetermined value, fuel is supplied from the auxiliary burner into the fluidized bed. Then, by burning this and raising the temperature of the fluidized bed to a predetermined value, control is performed to maintain the temperature of the hot air (dry gas) supplied to the dryer at a predetermined value.
For this reason, the use of expensive fuel oil cannot be excluded, and this has been a factor that hampers 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 recognizing such a background, and when a hot-air stove to which a fluidized bed combustion furnace is applied is used as a heat source of the dryer, the load of the dryer is kept constant to make the unit time The technical problem was to develop a new drying facility and its operating method that can keep the combustion state of the hot stove stable and operate at a low running cost, with the required heat quantity per unit being kept constant. Is.

That is, in the drying equipment according to claim 1, a supply device of the object to be treated faces the dryer, and a hot-air stove to which a fluidized bed combustion furnace is applied is connected to the hot-air blow-in opening. In the drying equipment having its discharge port facing the takeout conveyor, the drying equipment presets the moisture value of the dried product obtained by treating the object to be treated by the dryer, and the object to be treated in the dryer. By setting the water evaporation amount per unit time from, the operation is performed to keep the amount of heat per unit time required in the dryer constant, and further, the drying equipment is In addition to having a moisture meter to measure the value, control to automatically adjust the amount of material to be processed into the dryer so that the amount of water supplied to the dryer per unit time is constant. An apparatus is provided, and a water-containing waste solidified fuel is further used as the fuel for the hot-blast stove, based on the amount of water evaporated from the object to be processed per unit time set in the dryer. , A means for calculating the amount of heat per unit time required to dry the object to be dried to a desired moisture value, a conveyor for feeding the fuel into the hot stove, and the weight and moisture of the fuel located on this conveyor And means for measuring the value, and the amount of fuel input to the hot stove per unit time , calculated calorific value per unit time necessary for drying, and the measured fuel weight and water content. , the basis sets as just enough to generate the amount of heat per unit time required for drying was calculated, the control device for performing control for automatically adjusting a fuel input of the hot air furnace It is characterized by being provided.

Furthermore, in addition to the above requirements, the drying equipment according to claim 2 further comprises a conveyor for feeding fuel into the hot stove, and a means for measuring the weight and water content of the fuel located on the conveyor. It is characterized by being equipped with a base.

Furthermore, the drying equipment according to claim 3 is, in addition to the requirements according to claim 1 or 2, a means for spraying water into the hot stove, and the amount of fuel supplied to the hot stove per unit time from the hot air to the hot air. It is characterized in that it is provided with means for calculating the amount of water located in the furnace, and means for adjusting the amount of water sprayed into the hot air stove according to the amount of water in the hot air stove.

Further, in the method for operating the drying equipment according to claim 4, the feed device of the object to be treated is faced to the inlet of the dryer, and the hot-air stove to which the fluidized bed combustion furnace is applied is connected to the hot-air blow-in port. In addition, in the operating method of the drying equipment, in which the discharge conveyor faces the discharge port, the moisture value of the dried product obtained by treating the object to be treated by the dryer is preset, and the object to be treated in the dryer is By setting the amount of water vaporized per unit time from the object, operation is performed to make the amount of heat required in the dryer constant per unit time, and the moisture value of the object to be processed is measured during operation. In addition, by controlling the amount of the object to be treated per unit time to the dryer, the amount of water supplied to the dryer is automatically adjusted so as to be constant, and the water content of the hot stove is used as the fuel. The unit time required for drying the object to be treated to a desired moisture value based on the amount of water evaporated per unit time from the object to be treated, which is set in the dryer, using the waste solidified fuel. The amount of heat per unit time is calculated, and the weight and water content of the fuel located on the conveyor for charging the fuel into the hot blast stove are measured, and the amount of fuel injected into the hot blast stove per unit time is also calculated. Based on the amount of heat per unit time required to perform, and the measured fuel weight and water content, it is set so that there is no excess or deficiency to generate the calculated amount of heat per unit time required for drying. and, in which the input amount of fuel to heat air furnace comprising a feature to automatically adjust.

Furthermore, in addition to the requirements of claim 4, the operating method of the drying equipment according to claim 5 is characterized in that the fuel is introduced into the hot stove by a plurality of conveyors, and the weight of the fuel located on each conveyor. And measuring the water content.

Further, the method of operating the drying equipment according to claim 6 or, in addition to the requirements of the claims 4 or 5, wherein calculating the amount of water located from input amount per unit fuel time to the hot stove in a hot air furnace and, depending on the moisture content of the hot air furnace, those comprising as characterized by adjusting the watering amount to a hot air furnace.
The above problems can be solved by using the configurations of the invention described in each of these claims.

According to the first or fourth aspect of the present invention, the amount of water evaporated from the object to be treated in the dryer per unit time is constant, so that the dryer can be operated stably.
Also, since the amount of heat required per unit time 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 stove that is the hot air supply source Driving can be made stable.
That is, according to the invention described in claim 1 or 4, among the constituent elements of the drying equipment, the dryer and the hot-air stove, which are the main constituent elements, can be stably operated, so that the entire drying equipment can be stabilized. Will be realized.
Further, based on the amount of heat per unit time required for drying the material to be treated in the dryer, the solid waste fuel required to generate this amount of heat is supplied to the hot stove without excess or deficiency.
That is, since hot air is supplied from a hot air stove that is constantly operated to obtain a constant amount of heat to a dryer that constantly has a constant amount of water evaporation, these dryers and hot air stoves can be operated stably. It is possible to stabilize the entire drying equipment.
Incidentally, conventionally, when the required heat amount of the dryer fluctuates, that is, when the load of the hot stove fluctuates, the solid fuel is different from the liquid fuel in the hot stove when the input amount of the solid fuel is adjusted by PID control or the like. Not only it takes a long time to put in, but it also takes time until the heat due to self-combustion is released, so the solid fuel supply amount sometimes became excessive. According to these inventions, such a situation can be avoided.

Further, according to the invention of claim 2 or 5, it is possible to handle a plurality of kinds of waste solid fuels at the same time, and the waste solid fuels having different properties are respectively introduced into the hot stove in an appropriate amount. Therefore, it is possible to use the solid waste fuel at a ratio considering the availability and economic efficiency.
As a result, it becomes possible to suitably operate the drying equipment in a state according to the purpose, such as importance of stability and importance of economy.

Furthermore, according to the invention of claim 3 or 6, it is possible to bring the amount of water located in the hot stove to a suitable state, and prevent the temperature in the flow chamber from fluctuating excessively.
In addition, since it is possible to prevent the temperature inside the flow chamber from dropping excessively, it is not necessary to use the conventional fuel supply by the auxiliary burner, and fossil fuel is used only for ignition at startup. It is possible to drive at running cost.

It is a skeleton figure which shows a drying installation. It is the front view and side view which show a dryer. It is a side view showing a hot blast stove to which a fluidized bed combustion furnace is applied. It is a flowchart which shows the flow of control of the amount of sludge input to a dryer. It is a flowchart which shows the flow of control of the solid fuel input amount to a hot stove. It is a flowchart which shows the flow of control of the solid fuel input amount to a hot stove. It is a flowchart which shows the flow of control of the amount of water sprayed to a hot-blast stove. It is a skeleton view showing an existing drying facility. It is a skeleton figure which shows the existing drying installation which reheats exhaust gas and circulates it.

The best mode of the drying equipment and its operating method of the present invention is as shown in the following embodiments, but it is possible to make appropriate modifications to this embodiment within the scope of the technical idea of the present invention. ..

An example of the drying equipment of the present invention will be described below with reference to the drawings, and an operating method of the drying equipment of the present invention will be described together with an operating state of the equipment.
A skeleton is shown in FIG. 1 as a skeletal structure, which is a dryer 5 in which a sludge supply device 2 is faced to its inlet 51, and a hot air stove 3 is connected to its hot air blowing port 53. Further, the take-out conveyor 6 faces the discharge port 52.
Further, the hot air stove 3 is a fluidized bed combustion furnace, and is placed between the dryer 5 and the hot air stove 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 equipment 1 is provided with a control unit for controlling the components of the drying equipment 1, such as the hot-air stove 3 and the dryer 5.

Hereinafter, various members constituting the drying equipment 1 will be described in detail.
First, the sludge supply device 2 will be described. The sludge supply device 2 is provided with a screw conveyor 2a driven by an inverter motor M2 at the bottom of the supply hopper 20 to screw a substance to be dried such as sludge D stored in the supply hopper 20. An appropriate amount is discharged according to the number of rotations of the conveyor 2a (inverter motor M2).
Further, a relay conveyor 2b to which a belt-type measuring conveyor is applied is provided as an example at the next stage of the screw conveyor 2a, and the discharge portion of the relay conveyor 2b is installed so as to face the input port 51 of the dryer 5.
A moisture meter 21 for measuring the moisture value of the sludge D, which is the object to be treated, located on the relay conveyor 2b is provided.

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

In the hot-air stove 3 configured in this manner, a fluidized bed of the fluidized sand S is formed above the diffuser pipe 34 (fluid chamber 31) by the hot air supplied from the air supply port 33a, and in this state By supplying the solid fuel F from 32b, the solid fuel F is sent into the fluidized bed (flow chamber 31), and hot air is generated by self-combusting therein, and this hot air is discharged from the exhaust port 32a to the outside. It is released.
Note that the start-up burner 36a is ignited only when the hot-blast stove 3 is started up, and after the hot-blast stove 3 shifts to the steady operation, only the blowing by the fluidized blower 36b is performed.

Further, the charging device 35 includes a screw conveyor 35a driven by an inverter motor M3 provided at the bottom of the box-shaped container, and the solid fuel F contained in the container is rotated by the screw conveyor 35a (inverter motor M3). It emits an appropriate amount according to the number.
The screw conveyor 35a is provided with a relay conveyor 35b to which a belt-type measuring conveyor is applied as an example, and the input conveyor 35c to which a screw conveyor is applied is provided as an example to the next step of the relay conveyor 35b. To be The discharging part of the charging conveyor 35c is connected to the charging port 32b of 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.

And in this embodiment, which two systems of prior Kito input device 35 and the input device 351 and the input device 352 is arranged, by such a configuration is employed, for example, plural kinds of waste solid The fuel can be treated as the solid fuels F1 and F2 at the same time. Further, since the waste solid fuels F1 and F2 having different properties can be introduced into the hot blast stove 3 in appropriate amounts, it is possible to use the waste solid fuels at a ratio in consideration of availability, economical efficiency, etc. Becomes Of course, such an input device 35 may be provided in three or more systems, or may be provided in only one system.

Next, a description will be given of the dryer 5, in which a rotary drum dryer is applied as an example, and four support rollers 57 are arranged on the base B as shown in FIG. The cylindrical drum 50 is mounted on the support roller 57.
A chain 59 is wound around the drum 50 and the output shaft of the motor M51, and the motor M51 rotationally drives the drum 50. Further, both ends of the drum 50 are closed by the lid members 50a and 50b in a state where the boundaries are sealed.
Further, a shaft 55a provided so as to penetrate through the vicinity of the center of the drum 50 is rotationally driven by a motor M52, and the shaft 55a is provided with a stirring blade 55.
A hot air blowing port 53 is formed in the lid member 50a, and a loading port 51 is formed in a loading mechanism provided so as to penetrate the lid member 50a.
Further, an exhaust 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 a U-shaped trough, and a dry product P dropped into the U-shaped trough is screw-conveyed ( The inverter motor M6) is configured to be sequentially discharged by rotation. Of course, as the take-out conveyor 6, another conveyor such as a belt conveyor can be applied.

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

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, and the exhaust gas flow path 7 includes a dust collector 72 and An exhaust damper 73 and is provided.
The exhaust damper 73 is, for example, a device for opening and closing the blades by the rotation of the control motor to adjust or close the air volume of the passing gas, and such a damper has another configuration shown in this specification. Is also the same.
Further, a circulation fan 71 and a heat exchanger 78 are provided at the next stage of the exhaust damper 73, and the next stage of the heat exchanger 78 is branched into two passages and a flow rate adjusting valve 78a is provided at each flow passage. There is.

Further, the drying equipment 1 of the present invention includes the following sensors in addition to the sensors already described.
First, between the air supply damper 41 in the hot air flow path 4 and the exhaust port 32a in the hot air stove 3, the temperature sensor 42 and the probe of the blower meter 44 are arranged so as to be located therein.
Further, this is arranged such that the probe of the dry product moisture sensor 60 is located inside the U-shaped trough in 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 equipment 1 of the present invention has a configuration as described above as an example, and the operating state of this equipment will be described below, together with the method of operating the drying equipment of the present invention.
In the present invention, the control of the input amount of sludge D to the dryer 1, the control of the input amount of solid fuel F to the hot stove 3 and the control of the sprinkling amount to the hot stove 3 are interlocked in the drying facility 1. Yes, these respective controls will be sequentially described.
In the following description, RPF and RDF (hereinafter, referred to as solid fuel F) which are so-called biomass resources, water-containing waste solidified fuel, are used as the fuel of the hot blast stove 3, and are used as the object to be treated. Sludge D is dried to obtain dried product P.
When the drying equipment 1 is started, first, the starter burner 36a is ignited to start the hot-air stove 3, and when the drying gas G having a sufficient temperature can be obtained, the dryer 5 is processed. The sludge D, which is a product, is thrown in.

(1) Control of Amount of Sludge Input to Dryer First, in controlling the amount of sludge D input to the dryer 1, a process 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. B. And

Next, the amount of water evaporated from the sludge D (object to be treated) in the dryer 1 per unit time is set (step S12). In this example, 1944 kg/h was set 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. B. And

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

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

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

As described above, in the control of the amount of sludge D input to the dryer 1 of the present invention, the amount of water evaporated from the sludge D in the dryer 1 per unit time is constant, which is It also means that the amount of heat required per unit time is kept constant.
Therefore, the amount of heat generated in the hot-air stove 3 and supplied to the dryer 1 is also constant, and the amount of water evaporated from the sludge D per unit time (1944 kg/h) set in step S12 is Based on this, the theoretical amount of heat required for drying is calculated (step S17). In this embodiment, it is, for example, 5106686 kJ/h.

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

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

(2) Control of Input Amount of Solid Fuel to Hot Blast Furnace To control the input amount of solid fuel F to the hot blast stove 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, 300 kg/h was set as an example.

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

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

Next, the calorific value of the solid fuel F1 is manually set (step S24), and in this embodiment, it is set to 27209 kJ/kg as an example.

Then, using the set value and the measured value, the dry matter amount of the solid fuel F1, the water amount W1 and the generated heat amount are calculated (step S25). In this embodiment, as an example, 150 kg/h, 150 kg/h, 4081350 kJ/ It became 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 heat generation amount of the solid fuel F2 is manually set (step S31), and in this embodiment, it is set to 20930 kJ/kg as an example.

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

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

Next, the input amount of the solid fuel F2, the dry matter amount and the water amount W2 are calculated (step S34), and in this example, they are 235.17 kg/h, 211.65 kg/h and 23.52 kg/h, as an example. ..

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. The control is performed (step S36), and the drive frequency of the inverter motor M3 in the charging device 352 is automatically adjusted.
The weight of the solid fuel F2 is constantly measured by the relay conveyor 35b to which the belt type weighing conveyor is applied.

(3) Control of water sprinkling amount on hot blast stove When controlling the water sprinkling amount on hot blast stove 3, a process according to the flow shown in FIG. 7 is performed.
First, the total amount W of water to be introduced into the hot-blast stove 3 is set (step S41), and in this example, it was set to 600 kg/h.

Then watering amount W37 of water from sprinkler nozzles 37, the water W1 calculated in S25, is intended to calculate (W37 = W- (W1 + W2 ) with water W 2 calculated in S34 (step S42) In this example, the pressure was 426.48 kg/h as an example.

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

According to the invention, the amount of water located in the hot blast stove 3 can be set to 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-blast stove 3 becomes excessive due to some trouble, a flow for starting the auxiliary combustion burner 39 is added as surrounded by a broken line in FIG. 7. Good.

Further, as described above, according to the present invention, the amount of water evaporated from the object to be processed in the dryer 5 per unit time is constant, so that the operation of the dryer 5 can be made stable.
Further, since the amount of heat required per unit time in the dryer 5 is constant, the temperature of the hot air (drying gas G) supplied to the dryer 5 can be constantly kept constant, which is a hot air supply source. The operation of the hot-blast stove 3 can be made stable. That is, among the components of the drying equipment 1, the dryer 5 and the hot-air stove 3, which are the main components, can be stably operated, so that the entire drying equipment 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 to generate this amount of heat is supplied to the hot stove 3 without excess or deficiency. Will be supplied. That is, since hot air (dry gas G) is supplied from the hot-air stove 3 that is operated so that a constant amount of heat is constantly obtained to the dryer 5 that always has a constant amount of water evaporation, these dryers 5 and The hot blast stove 3 can be stably operated, and the entire drying equipment 1 can be stabilized.
Incidentally, conventionally, when the required heat amount of the dryer 5 changes, that is, when the load of the hot stove 3 changes, 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. In addition to the time required for charging the hot air stove 3 into the hot blast stove 3, it also takes time for the heat generated by self-combustion to be released, so that the solid fuel F is supplied in an excessive amount. However, according to these inventions, such a situation can be avoided.

Furthermore, according to the present invention, a plurality of types of solid fuel F (waste solid fuel) can be handled at the same time, and the solid fuels F having different properties can be introduced into the hot stove 3 in appropriate amounts. Therefore, the solid fuel F can be used at a ratio in consideration of availability, economy, and the like. As a result, it becomes possible to operate the drying equipment 1 in a state suitable for the purpose, such as importance of stability and importance of economy.

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

1 drying equipment

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

3 Hot Air Stove 31 Flow Chamber 31a Air Supply Port 32 Exhaust Chamber 32a Exhaust Port 32b Input Port 32c Air Supply Port 33 Fluid Air Blow Chamber 33a Air Supply Port 34 Diffuser Tube 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 Sprinkling nozzle 37a Sprinkling valve 38 Temperature sensor 39 Auxiliary burner

4 Hot Air Flow Path 4B Exhaust Flow Path 41 Air 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 blowing port 54 Exhaust port 55 Stirring blade 55a Shaft 57 Support roller 59 Chain

6 Take-out conveyor 60 Dry product moisture sensor

7 Exhaust Gas Flow Path 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 (6)

With respect to the dryer, the feed port of the object to be treated is faced to the dryer, the hot air blower is connected to the hot air stove to which the fluidized bed combustion furnace is applied, and the outlet is exposed to the takeout conveyor. In the drying equipment consisting of
This drying equipment, by presetting the moisture value of the dried product obtained by treating the object to be treated by the dryer, by setting the amount of water evaporation per unit time from the object to be treated in the dryer, An operation is performed in which the amount of heat required per unit time in the dryer is constant,
Further, the drying equipment is equipped with a moisture meter for measuring the moisture value of the object to be treated, and the object to be treated is put into the dryer so that the amount of water supplied to the dryer per unit time becomes constant. A control device for automatically controlling the amount is provided,
Further, a water-containing waste solidified fuel is used as the fuel for the hot stove,
Set in the dryer, based on the amount of water evaporation per unit time from the object to be processed, means for calculating the amount of heat per unit time required to dry the object to be processed to a desired moisture value,
A conveyor for charging fuel into the hot stove, and means for measuring the weight and water content of the fuel located on the conveyor,
Also, the amount of fuel input to the hot stove is calculated based on the calculated amount of heat per unit time required for drying, and the measured fuel weight and water content. Drying facility characterized by being equipped with a control device that is set so that there is no excess or deficiency to generate a specific amount of heat per unit time and that automatically controls the amount of fuel input to the hot stove ..
2. The drying apparatus according to claim 1, wherein a plurality of conveyors for feeding fuel into the hot-blast stove and means for measuring the weight and water content of the fuel located on the conveyor are provided. Facility.
Means for watering the hot air 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;
The drying facility according to claim 1 or 2, further comprising: a unit that adjusts the amount of water sprayed into the hot stove according to the amount of water in the hot stove.
With respect to the dryer, the feed port of the object to be treated is faced to the dryer, the hot air blower is connected to the hot air stove to which the fluidized bed combustion furnace is applied, and the outlet is exposed to the takeout conveyor. In the operating method of the drying equipment consisting of,
By presetting the moisture value of the dried product obtained by treating the object to be treated by the dryer, and by setting the amount of moisture evaporation per unit time from the object to be treated in the dryer, it is necessary in the dryer. The operation is performed with a constant amount of heat per unit time,
Further, the water content of the object to be processed is measured during operation, and the amount of the object to be processed per unit time to the dryer is controlled so that the amount of water supplied to the dryer is automatically adjusted to be constant. And
Using water-containing waste solidified fuel as a fuel for the hot stove,
Set in the dryer, based on the water evaporation amount per unit time from the object to be processed, calculate the amount of heat per unit time required to dry the object to be processed to a desired water content value,
While measuring the weight and water content of the fuel located on the conveyor for feeding the fuel into the hot stove,
Also, the amount of fuel input to the hot stove is calculated based on the calculated amount of heat per unit time required for drying, and the measured fuel weight and water content. the method of operating the drying equipment, characterized in that set to just enough to generate the amount of heat per unit such time, automatically adjusts the input amount of fuel to heat air furnace.
The method for operating a drying facility according to claim 4, wherein the fuel is introduced into the hot stove by a plurality of conveyors, and the weight and water content of the fuels on the respective conveyors are measured.
Wherein calculating the amount of water located in the hot air furnace from the feeding amount per unit time of the fuel into the hot air oven, in accordance with the moisture content of the hot air furnace, adjusting the watering amount to a hot air furnace The method for operating the drying equipment according to claim 4 or 5.

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