Operation method of horizontal continuous conduction heat transfer dryer

Abstract

To develop a novel method of operating a horizontal continuous dryer of a conductive heat transfer type, capable of maintaining the amount of objects to be processed being charged into a horizontal continuous dryer of a conductive heat transfer type constant, by changing the moisture content in a dried product within a range acceptable by a post stage facility.SOLUTION: A horizontal continuous dryer 1 of a conductive heat transfer type comprises a shaft body 113 equipped with a heat transfer member disposed in a body shell 10, flows heating steam into the shaft body 113 and rotate, and while making an object P to be processed fed into the body shell 10 stay in the body shell 10, brings the same into contact with the heat transfer member rotating with the shaft body 113 to obtain a dried product D thereof, and further comprises a plurality of feed ports 101 formed on a plurality of positions on the upper part of the body shell 10 and a temperature sensor 13 disposed in the body shell 10 below the feed ports 101. A method of operating the horizontal continuous dryer 1 of a conductive heat transfer type is characterized by performing fuzzy inference using a material temperature value measured by the temperature sensor 13 as a condition and a feed rate of the object P to be processed being fed from feed ports 101 as a conclusion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a horizontal continuous conduction heat transfer dryer suitable for drying materials in a muddy, cake-like, powdery, or granular state, and in particular to an operating method for a horizontal continuous conduction heat transfer dryer that can avoid problems such as adhesion even when the physical properties of the material to be treated fluctuate, and can avoid operation that results in inefficient drying, such as the dried product becoming too dry. [Background technology]

[0002] Recently, environmental conservation efforts have become more common, and companies are now drying and concentrating general waste such as food waste and food processing residues, as well as sewage sludge, to reduce their volume and prevent decay before recycling or disposing of them. While it is desirable for the physical properties of materials to be dried to be constant, in reality, these properties tend to fluctuate, and even in factory products that produce wet powders and granules after dehydration, the moisture content of the wet powders and granules often fluctuates.

[0003] One of the devices used for drying such sludge, etc. is a horizontal continuous conduction heat transfer dryer 1'. As shown in Fig. 7, for example, this device is provided with a multi-tubular heating pipe 11' inside a main body shell 10', and this multi-tubular heating pipe 11' is rotated while heating steam is circulated inside, and the material to be treated P is brought into contact with this pipe to evaporate moisture (see, for example, Patent Document 1). In addition to this, there is also a device that consists of a hollow shaft inside a long horizontal casing and a hollow stirring member that protrudes from this shaft, and by passing heating steam through these hollow parts and rotating them, it evaporates moisture and other substances from the material to be treated that has been placed inside the casing (see, for example, Patent Document 2).

[0004] Now, regarding the horizontal continuous conduction heat transfer dryer 1', the material P to be treated is supplied into the main shell 10' from the inlet 101', is lifted up by the lifter 117', and moves toward the overflow outlet 102' as the drying progresses, and is discharged to the outside from the overflow outlet 102' through the duct 107' in the form of a dried product D. Such a horizontal continuous conduction heat transfer dryer 1' has a plurality of main body shells 10' arranged along the longitudinal direction thereof. pieces There is an insertion port 101' (in FIG. 7, there are three insertion ports 101a' to 101c'). pieces By changing the distribution of the materials P fed into each of the feeding ports 101′, the moisture value of the materials P that are in contact with the multi-tubular heating pipe 11′ and staying in the main body shell 10′ is adjusted, and an operation is performed in which the moisture value of the dried product D discharged from the horizontal continuous conduction heat transfer dryer 1′ is kept at a predetermined value. The material P to be treated is supplied to each of the inlets 101' by a supply conveyor (not shown) and by opening and closing a damper (not shown) provided between the supply conveyor and the inlet 101', and the opening and closing of the damper is performed by a timer setting. The timer setting is changed by an operator after checking the operating state based on information from a temperature sensor (not shown) installed inside the main body shell 10'.

[0005] Furthermore, if the workpiece P becomes unable to be dried or the dried product D becomes too dry during operation after changing the timer setting, the operator can change the setting by lowering or raising the input setting amount of the workpiece P, and by changing the timer setting of each damper, the main body shell 10 ′ The object P to be treated is adjusted so that it is in a state suitable for drying.

[0006] However, the horizontal continuous conduction heat transfer dryer 1' is generally operated to maintain a high filling rate, in which the heat transfer members (heat pipe bundle 116') inside the dryer come into contact with the materials P over a wide area and a large area, in order to increase the drying efficiency. Therefore, the materials P inside the dryer do not move in a simple piston flow manner toward the outlet side (overflow port 102'). Furthermore, because the filling rate is high, the effect of the materials P with different physical properties that are continuously added to the machine is reflected in the changes in the amount of materials P filled inside the machine only gradually, making it very difficult for the operator to constantly monitor this and make the above-mentioned setting changes. The same phenomenon can occur in the horizontal continuous conduction heat transfer dryer of the type described in Patent Document 2. In such a dryer, in order to avoid problems such as adhesion, multiple pieces In this case, the positions of the (second) inlets provided at the respective locations are adjusted, and the amounts of materials to be treated that are fed therein are also adjusted. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2005-331210 [Patent Document 2] Patent Publication No. 2004-150641 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention was made against this background, and the technical objective was to develop a new operating method for a horizontal continuous conduction heat transfer dryer that can continue operation even when the physical properties of the treated material change, without causing problems such as adhesion that makes it difficult to continue operation, or without causing the dried product to become overly dry, and without the need to adjust the structural position of the inlet. [Means for solving the problem]

[0009] That is, the operating method of the horizontal continuous conduction heat transfer dryer according to claim 1 is as follows: A shaft having a heat transfer member is disposed in the main body shell, and the shaft is rotated while heating steam is passed through the shaft. A horizontal continuous conduction heat transfer dryer in which a workpiece is placed in the main body shell, and the workpiece is brought into contact with a heat transfer member that rotates together with the shaft while remaining in the main body shell, thereby obtaining a dried product of the workpiece, A plurality of inlets are formed in the upper part of the main body shell, An overflow outlet is provided at the rear of the main body shell, and below and behind each inlet Inside the main body shell ,each, A method for operating a horizontal continuous conduction heat transfer dryer in which a temperature sensor is disposed, comprising: Book The said disposed within the body shell Each The condition part is the product temperature measured by the temperature sensor, The aforementioned Each This method is characterized by performing fuzzy inference with the speed at which the material is fed from the feed port as the conclusion.

[0010] Also, claims 2 The method for operating the horizontal continuous conduction heat transfer dryer described in the claims 1st article In addition to the requirements listed above, The inlet 1 Therefore, when an object to be treated is being fed into one of the feed ports, no object to be treated is being fed into another feed port.

[0011] The method of operating the horizontal continuous conduction heat transfer dryer according to claim 4 can be carried out in the same manner as claim 1. or 2 In addition to the requirements listed, The aforementioned Each Insertion from the inlet 、 It is characterized by being carried out in a prescribed order. The above problems are solved by the configurations of the inventions described in each claim. [Effects of the Invention]

[0012] First, according to the invention described in claim 1, the speed at which the material to be treated is fed into the main body shell from the feeding port is set based on the temperature of the material to be treated inside the main body shell. R This prevents situations where it becomes difficult to continue operation due to adhesion or the dried product becoming too dry, and allows dried products with a constant moisture content to be discharged from the dryer. Furthermore, since the speed at which the materials to be treated are fed into the feed ports is set based on membership functions in fuzzy control, it is possible to reflect subtle changes in product temperature in the feed speed, and of course, even if an operator is absent or if the operator is replaced, the supply of materials to each feed port can always be optimized. Furthermore, according to the present invention, the speed at which the material to be treated is fed into the feed port located above and in front of the temperature sensor can be adjusted appropriately in accordance with the value of the product temperature detected by the temperature sensor.

[0013] Also, claims 2 According to the described invention, the control rules in fuzzy control are simplified, and the setting and adjustment of fuzzy control in actual operation can be performed easily and reliably. In addition, it is possible to more reliably avoid situations where it becomes difficult to continue operation due to adhesion, etc., or situations where the dried product becomes too dry, and to make the moisture content of the dried product discharged from the dryer a more desirable value.

[0014] Also, claims 3 According to the described invention, the control rules in fuzzy control are simplified, and the setting and adjustment of fuzzy control in actual operation can be performed easily and reliably. In addition, it is possible to more reliably avoid situations where it becomes difficult to continue operation due to adhesion, etc., or situations where the dried product becomes too dry, and to make the moisture content of the dried product discharged from the dryer a more desirable value. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a partially cutaway side view of a horizontal continuous conduction heat transfer dryer to which the present invention is applied. [Figure 2] 10 is a vertical cross-sectional view illustrating the positional relationship between the insertion port and a temperature sensor disposed inside the main body shell. FIG. [Figure 3] FIG. 10 is a partially cutaway side view of a horizontal continuous conduction heat transfer dryer according to another embodiment. [Figure 4-1] This is a graph showing the membership function of "product temperature T1," which is the condition part of fuzzy inference. [Figure 4-2] This is a graph showing the membership function of "product temperature T2," which is the condition part of fuzzy inference. [Figure 4-3] This is a graph showing the membership function of "product temperature T3," which is the condition part of fuzzy inference. [Figure 5]This is a table showing a fuzzy inference rule with a condition part of "product temperature T1" and a conclusion part of "feeding speed V1", a fuzzy inference rule with a condition part of "product temperature T2" ​​and a conclusion part of "feeding speed V2", and a fuzzy inference rule with a condition part of "product temperature T3" and a logic part of "feeding speed V3". [Figure 6] This is a table showing the combinations of conclusions determined according to the rules of fuzzy inference shown in Figure 5 and the input speeds. [Figure 7] FIG. 1 is a partially cutaway side view of an existing horizontal continuous conduction heat transfer dryer. DETAILED DESCRIPTION OF THE INVENTION

[0016] The best mode of operation of the horizontal continuous conduction heat transfer dryer of the present invention is as shown in the following example, but appropriate modifications can be made to this example within the scope of the technical concept of the present invention. [Example]

[0017] Hereinafter, the horizontal continuous conduction heat transfer dryer 1 and peripheral equipment to which the present invention is applied will be described, and then the operating method of the present invention will be described. First, the horizontal continuous conduction heat transfer dryer 1 is an apparatus suitable for drying a material P to be treated that is in a muddy, cake-like, powdery or granular state, and is an apparatus for obtaining a dried product D by retaining the material P to be treated while evaporating volatile components such as moisture. As shown in Figs. 1 and 2, this is a dryer in which a multi-tubular heating pipe 11 is provided inside a main body shell 10 provided on a machine frame F, and this multi-tubular heating pipe 11 is rotated while steam as a heating medium flows inside it, and the material P to be treated is retained inside the main body shell 10 and brought into contact with the multi-tubular heating pipe 11 to dry. The inlet 101, probe insertion tube 109, rotary joint 115, outlet 122, supply tube 123, input damper 124, temperature sensor 13, etc., which will be described later, are provided in multiple locations, and when distinguishing between individual elements, lowercase letters such as a, b, c, etc. are used as secondary symbols.

[0018] The main body shell 10 is, for example, a hollow member having an oblong cross section, and is formed with an inlet 101, an overflow port 102, a carrier gas port 103, and an exhaust port 104. Hereinafter, in this specification, the overflow port 102 side (the right side in FIGS. 1 and 2) will be referred to as the "rear" and "rearward", and the opposite side will be referred to as the "front" and "forward". The inlets 101 are formed at multiple locations on the upper part of the main body shell 10. For example, in FIG. 1, a first inlet 101a is formed in front of a carrier gas inlet 103 formed on the upper front part of the main body shell 10. A second inlet 101b and a third inlet 101c are formed between the carrier gas inlet 103 and an exhaust port 104 formed on the upper rear part of the main body shell 10.

[0019] The locations of the supply port 101, carrier gas port 103 and exhaust port 104, as well as the number of exhaust ports 104, may be changed as appropriate within the scope of the technical concept of the present invention.

[0020] Above the inlet 101, for example, a supply conveyor 12 having a screw 121 provided in a trough 120 is disposed, and discharge ports 122a to 122c formed in the lower part of the trough 120 are connected to the inlets 101a to 101c by supply pipes 123a to 123c. Furthermore, the supply pipes 123a to 123c are provided with input dampers 124a to 124c therein. The material P to be treated is fed into the supply conveyor 12 from the feed port 125 formed at the top of the trough 120, and by rotating the screw 121 and opening the feed dampers 124a to 124c corresponding to the desired feed ports 101a to 101c, the material P is fed from the discharge port 122 through the supply pipe 123 to the desired feed port 101, and from there into the main body shell 10. The conveying speed of the supply conveyor 12 is changed by a motor M2 whose rotation speed is controlled by an inverter INV2, and the conveying speed is changed as needed by a signal sent from a PLC (programmable logic controller) to the inverter INV2.

[0021] The main body shell 10 and the multi-tubular heating pipe 11 are installed in the machine frame F in a horizontal state, or are installed in the machine frame F at an incline so that the overflow port 102 side is somewhat lower. Furthermore, the main body shell 10 has a double jacket structure, and a steam passage is formed from a steam supply port 105 formed near the inlet 101a to a drain port 106 formed below the overflow port 102, thereby enabling the temperature inside the main body shell 10 to be raised. Note that instead of such a double jacket structure, a tracing pipe or the like can also be installed.

[0022] 1, the overflow port 102 can be formed to a desired height by covering a square opening formed in the main body shell 10 with a plurality of plates 102b, each about 10 cm wide, in order from bottom to top. The dried product D will then go over these plates 102b and be discharged out of the main body shell 10. Because of this configuration, if the plate materials 102b are piled up high, the opening of the overflow port 102 opens only narrowly at the top, and a large amount of the object P to be treated remains inside the main body shell 10. Conversely, if there are fewer plate materials 102b, the opening becomes wider, and the amount of the object P to be treated remaining inside the main body shell 10 decreases.

[0023] A duct 107 is fitted on the exterior to cover the overflow port 102, and a rotary valve 108 is provided in front of an outlet 107a formed in the lower part of the duct 107. Of course, a double damper discharge device or the like may be provided in place of the rotary valve 108.

[0024] The multi-tubular heating tube 11 is provided with end plates 112 on both sides of a heat pipe bundle 116 as a heat transfer member formed by arranging a plurality of tubes in a cylindrical shape, and with a shaft 113 at the center of the end plates 112, and the shaft 113 is rotatably supported by a bearing block 114 provided on the machine frame F. A motor M1 is provided on the machine frame F as a drive device for rotating the multi-tubular heating tube 11. Rotary joints 115 (115a, 115b) are attached to both ends of the shaft 113 and connected to a heat pipe bundle 116. A sealing mechanism is provided between the shaft 113 and the main body shell 10 to block the outside air. The heat pipe bundle 116 is provided on its periphery with a number of angles 111 (12 in this embodiment) to which are attached a plurality of lifters 117 and feed blades 118 at appropriate angles, and these lift the material P to be treated, causing it to come into contact with the heat pipe bundle 116 and move from the inlet 101 side to the overflow outlet 102 side.

[0025] Furthermore, probe insertion tubes 109a to 109c are provided on the circumferential surface of the main body shell 10, through which probes of temperature sensors 13a to 13c such as thermocouples are inserted into the main body shell 10, so that the temperature of the workpiece P at various locations within the main body shell 10 can be measured. In this embodiment, as shown in Fig. 2, temperature sensor 13a is disposed on the rear side immediately below input port 101a. Temperature sensor 13b is disposed on the rear side immediately below input port 101b. Furthermore, temperature sensor 13c is disposed on the rear side immediately below input port 101c. To explain the positions of these temperature sensors 13 in more detail, they are preferably provided on the side of the main body shell 10 in the rotation direction in which the object P is lifted up by the heat pipe bundle 116 and the lifter 117, and are in a state where they are always in contact with the object P (intermediate product P1) already positioned inside the main body shell 10, and are located behind the area directly below the input port 101 so that the object P does not come into contact with the temperature sensor 13 immediately after it is dropped into the input port 101. Place in .

[0026] Although not shown, a steam generator is installed in addition to the horizontal continuous conduction heat transfer dryer 1, and an appropriate device such as a U-shaped, straight pipe, or helical coil type is used. A pipe is connected from this steam generator to the rotary joint 115a and the steam supply port 105 in the horizontal continuous conduction heat transfer dryer 1. A carrier gas is supplied into the main body shell 10 from a carrier gas port 103. Volatile components volatilized from the workpiece P by heating in the multi-tubular heating tube 11 are carried away by the carrier gas to the outside of the main body shell 10 through an exhaust port 104. Since the carrier gas contains not only the volatile components but also fine powder generated from the workpiece P, a dust removal device (not shown) may be provided on the path along which the carrier gas flows after the exhaust port 104.

[0027] 1, a supply hopper 2 is provided upstream of the supply conveyor 12, and the materials P are discharged in fixed amounts from the supply hopper 2 to the supply conveyor 12. The supply hopper 2 has a hopper section 21 at its top for storing the materials P, and a screw conveyor section 22 directly connected to the bottom of the hopper section 21, thereby discharging the materials P. The screw 23 of the screw conveyor section 22 is driven by a motor M3 whose rotation speed is controlled by an inverter INV3.

[0028] The weight of the supply hopper 2 is measured at regular intervals by a load cell 25, and a control signal is sent from the discharge weight controller WIC to the inverter INV3 at regular intervals so that the weight of the material P discharged by the screw 23 is equal to the set value set in the discharge weight controller WIC, and the inverter INV3 controls the rotation speed of the motor M3 based on this control signal. The set value of the discharge weight controller WIC is set as needed by a signal sent from a PLC, which will be described later in detail. Note that, as long as it is possible to feed the material P to the supply conveyor 12 and the supply speed of the material P can be changed based on a control signal, the configuration of the supply hopper 2 is not limited to the above-described configuration and can be applied.

[0029] Furthermore, a pump capable of transporting sludge (hereinafter, sometimes referred to as a sludge pump) can be applied as an alternative to the supply conveyor 12. In detail, an individual sludge pump is connected to each of the inlets 101a to 101c (described later) by piping, and the supply and stop of the material P to be treated is performed by operating and stopping the specified sludge pump. In this case, the sludge supply rate of the sludge pump corresponds to the "feeding rate," which will be described in detail later. If the sludge pump is operating, sludge (material to be treated P) is fed, and if it is stopped, the feeding of sludge may stop. However, if the sludge has high fluidity, an automatically operated valve may be provided on each supply pipe 123 near each feed port 101, and the feeding of sludge may be started or stopped by the operation of each automatically operated valve. Furthermore, it is also possible to use one sludge pump, with piping branching out and connecting to the inlets 101a to 101c, and to provide automatically operated valves in each piping path that can supply and cut off the material P to be treated.

[0030] The temperature signals of the product temperatures measured by the temperature sensors 13a to 13c are input to a programmable logic controller (PLC) (not shown). The PLC is equipped with a circuit for performing fuzzy inference, which will be described in detail later, and fuzzy inference is performed based on the temperature signals input to the PLC. The signal corresponding to the input speed of the workpiece P from each input port 101a to 101c, which is the result of the fuzzy inference, is input from the PLC to the discharge weight controller WIC and inverter INV3, and the workpiece P is discharged from the supply hopper 2 according to the input speed and transported on the supply conveyor 12. The input dampers 124a to 124c below the supply conveyor 12 are opened and closed in a sequence predetermined by the PLC.

[0031] The horizontal continuous conduction heat transfer dryer 1 and peripheral equipment to which the present invention is applied are configured as described above as an example, and the operating method of the horizontal continuous conduction heat transfer dryer of the present invention will be described below along with the operating modes of this device and peripheral equipment.

[0032] (1) Preparing the dryer First, prior to the introduction of the material to be treated P, the multi-tubular heating tube 11 and the main body shell 10 in the horizontal continuous conduction heat transfer dryer 1 are heated, and after heating steam is supplied to the rotary joint 115a and the steam supply port 105, the motor M1 is started to rotate the multi-tubular heating tube 11. The heating steam supplied to the rotary joint 115a increases the temperature of the multi-tubular heating tube 11 while passing through the heat tube bundle 116, and eventually becomes drain, which is discharged to the outside from the rotary joint 115b on the other end side. In addition, the heating steam supplied to the steam supply port 105 increases the temperature of the main body shell 10, and eventually becomes drain, which is discharged to the outside from the drain port 106. A siphon pipe (not shown) is provided inside end plate 112 on the rotary joint 115b side, and a steam trap (not shown) is provided in the path through which the drain discharged from rotary joint 115b flows. Also, a steam trap (not shown) is provided in the path through which the drain discharged from drain port 106 flows.

[0033] (2) Drying of the treated material Next, the material to be treated P (for example, 70 to 80% WB) is charged into the charging port 101, and this material moves from front to rear by the action of the feed blades 118, and is further lifted up by the lifter 117 to come into contact with the heat tube bundle 116, etc., at which point it receives heat and is dried. At this time, since the charging ports 101 are formed at multiple locations along the longitudinal direction of the multi-tubular heating tube 11 (charging ports 101a to 101c), the heat conduction surface of the multi-tubular heating tube 11 can be used effectively, and drying efficiency can be improved. Note that the inside of the end plate 112 is filled with heating steam, so the surface portion of the end plate 112 also acts effectively to dry the material to be treated P. The object to be treated P located inside the main body shell 10 is also referred to as an intermediate product P1. Then, the object to be treated P (intermediate product P1) that has been dried becomes a dried product D, flows out from the overflow port 102, and is discharged to the outside from the discharge port 107a.

[0034] In addition, when the start-up operation for drying the workpiece P is started from an empty state inside the main shell 10, the workpiece P is gradually introduced through the inlet 101 and dried until the main shell 10 reaches a predetermined filling rate or until the product temperature, which will be described later, reaches a predetermined temperature, and then the operating method of the present invention is executed. In addition, start-up operation may also be performed when the main shell 10 is not empty, for example, when the drying operation is restarted after being interrupted, or when a predetermined amount of the material P to be treated, the moisture content of which has been reduced in advance, is introduced into the main shell 10, and then the original material P to be treated (the moisture content of which has not been reduced in advance) is introduced.Similarly, the operating method of the present invention is performed using the filling rate or a predetermined product temperature as an indicator.

[0035] Generally, horizontal continuous conduction heat transfer dryers dry the material P inside the dryer by contacting the surface of the heat transfer member, and therefore are operated while maintaining a high filling rate of the material P inside the dryer. If the physical properties of the material P to be treated change, especially if the moisture content changes to a value higher than the standard value at the time of design, the influence of the moisture content change will gradually appear because the operation is performed while maintaining a high filling rate. current If the operating conditions are not changed in accordance with the changes in temperature, adhesion will occur, drying will not progress, and it will become difficult to continue operating. Conversely, if the moisture content changes to a lower level, the change in moisture content will also occur gradually, and the material P inside the machine will become too dry, resulting in a decrease in the energy efficiency of the drying operation. In either case, it is necessary to understand the changes in the material P to be treated inside the machine and maintain the moisture content of the material P to be treated inside the machine at an appropriate value so as to prevent adhesion and to maintain an energy-efficient state.Since it has been discovered that there is a strong correlation between moisture and product temperature, the present invention uses the product temperature of the material P to be treated inside the machine (inside the main body shell 10) for control.

[0036] (3) Fuzzy control Specifically, the fuzzy control in the operating method of the horizontal continuous conduction heat transfer dryer of the present invention performs fuzzy inference in which the measured product temperatures (product temperature T1, product temperature T2, product temperature T3) from the temperature sensors 13a, 13b, 13c installed in the main body shell 10 are used as the condition part, and the set values ​​(V1, V2, V3) of the input speed of the workpiece P from the input ports 101a, 101b, 101c are used as the conclusion part.

[0037] (i) Creation of membership functions First, for each of the condition parts of the fuzzy inference, "item temperature T1," "item temperature T2," and "item temperature T3," the membership functions for the linguistic variables and attributes of each item are determined as shown in Figures 4-1, 4-2, and 4-3. The number of linguistic variables (labels) for such attributes and the membership functions for these linguistic variables are determined based on empirical rules, and are tuned appropriately depending on the type and physical properties of the workpiece P, the scale and configuration of the system, etc. Here, the product temperatures T1, T2, and T3 correspond to the temperatures of the object to be treated P (intermediate product P1) measured by the temperature sensors 13a, 13b, and 13c.

[0038] (ii) Deriving attributes and relevance Then, the membership function is used to derive the degree of suitability for each attribute. Specifically, for example, when the measured value of the product temperature T1 is 70°C, it is read from the membership function graph shown in Figure 4-1 that the attribute is NL and the compatibility is 1.0. Similarly, when the measured value of product temperature T2 is 85°C, the membership function graph shown in Figure 4-2 indicates that the attribute is ZR and the compatibility is 1.0. Furthermore, when the measured value of product temperature T3 is 90°C, the membership function graph shown in Figure 4-3 indicates that the attribute is PL and the compatibility is 1.0.

[0039] (iii) Conclusion Next, fuzzy inference is performed to determine a conclusion for the linguistic variables of the conditional part, and as an example, this is performed according to the rules shown in Figure 5. Here, the conclusion part is the input speed V1 of the workpiece P from the input port 101a, the input speed V2 from the input port 101b, and the input speed V3 from the input port 101c. Such fuzzy reasoning is intended to keep the moisture content of the treated material P inside the main shell 10 at an appropriate dry state while maintaining the moisture content of the dried product D discharged from the main shell 10 at a predetermined value.

[0040] Here, FIG. 6 is a table showing the combinations of conclusions determined by fuzzy inference according to the rules shown in FIG. 5 and the input speed of the workpiece P from each input port 101 that is changed according to these conclusions. First, in FIG. 6, pattern No. 14 shows the feeding speeds V1 to V3 of the workpiece P into each of the feeding ports 101a to 101c in the "standard state."

[0041] In the "reference state," if the material P to be treated in the horizontal continuous conduction heat transfer dryer 1 is, for example, sludge, the moisture content is 77% WB, the feeding speed V1 at the inlet 101a is 580 kg / h, the feeding speed V2 at the inlet 101b is 680 kg / h, and the feeding speed V3 at the inlet 101c is 740 kg / h. The material to be treated P is introduced into each of the inlets 101a, 101b, and 101c in that order. Tour The time required for one cycle is, for example, 3600 seconds, and in this embodiment, the insertion port 101 is 3 pieces It is a place, 1 pieces The input time was set to 1200 seconds per location. Of course, the time for one cycle can be changed. For example, the time for one cycle can be set to 600 to 7200 seconds. pieces The input time per unit is set to 200 to 2400 seconds, and this can be changed during the drying operation.

[0042] The "reference state" is a state in which the product temperature T1 has a conformance of 1.0 within the range of 77 to 83°C in the graph of Figure 4-1, the product temperature T2 has a conformance of 1.0 within the range of 82 to 88°C in the graph of Figure 4-2, and the product temperature T3 has a conformance of 1.0 within the range of 82 to 88°C in the graph of Figure 4-3, and the label of the conclusion part of the fuzzy inference is ZR for all of the set values ​​of the feeding speeds V1, V2, and V3.

[0043] To explain one cycle of operation when the "reference state" continues, first, the material P to be treated is fed into inlet 101a at a rate of 580 kg / h for 1200 seconds, then the material P to be treated is fed into inlet 101b at a rate of 680 kg / h for 1200 seconds, and then the material P to be treated is fed into inlet 101c at a rate of 740 kg / h for 1200 seconds, which constitutes one cycle. Control signals are input from the PLC to the discharge weight controllers WIC, INV3 and INV2 so that the material P to be treated is fed into each of these feed ports 101a to 101c at the above-mentioned feed speed and time, and the material P to be treated is discharged from the supply hopper 2 and transported on the supply conveyor 12. Although it is necessary to take into consideration the control of the transport time, in this embodiment only the matters that are essentially necessary are explained.

[0044] If we express the insertion speed from each insertion port 101a to 101c in the "reference state" as a ratio, then if the insertion speed from insertion port 101a is 100, the insertion speed from insertion port 101b is 117 and the insertion speed from insertion port 101c is 128. The input speed or ratio in this "reference state" is determined based on the preferred value obtained during prior operation when the so-called standard workpiece P at the time of design was input and operation was carried out. In addition, in a horizontal continuous conduction heat transfer dryer 1 equipped with multiple inlets 101, it tends to be preferable to set the input speed or ratio of the material P to be fed from each inlet 101 to a higher value for the inlet 101 located closer to the overflow outlet 102 (the so-called outlet side), in order to discharge a dried product D with stable moisture content.

[0045] As described above, if the goodness of fit of ZR of all the membership functions in the condition parts for each of the product temperatures T1 to T3 is 1.0, by performing the above-described operation, the material P to be treated can be discharged as a dried product D with a constant moisture content from the discharge port 107a without adhesion to the multi-tubular heating tube 11 or excessive drying. The order in which the workpiece P is fed into the feed ports 101a to 101c can be changed as appropriate depending on the configuration of the horizontal continuous conduction heat transfer dryer 1 and the properties of the workpiece P. For example, one cycle of feeding may be performed in the order of feed port 101a, then feed port 101c, and then feed port 101b.

[0046] Next, a case where the product temperatures T1 to T3 of the treatment object P in the main body shell 10 are different from the above-mentioned "reference state" will be described. Although the temperature sensors 13a to 13c constantly measure the product temperatures T1 to T3, fuzzy inference is performed based on the temperature detected by the temperature sensor 13 corresponding to the inlet 101 where no product is being added. The PLC then sets the rate at which product is to be added to the inlet 101 in the next step in a predetermined order based on the conclusion of the fuzzy inference immediately before the start of product addition. For example, if the product temperature T1 is 74°C, the graph in Figure 4-1 shows that the attribute is NL and the compatibility is 1.0, and the conclusion for the input speed V1 in Figure 5 is NS. Furthermore, when the product temperature T2 is 85°C, the graph in Figure 4-2 shows that the attribute is ZR and the compatibility is 1.0, and the conclusion for the input speed V2 in Figure 5 is ZR. Furthermore, when the product temperature T3 is 90°C, from the graph in Figure 4-3, the attribute is PL, the compatibility is 1.0, and the conclusion part of the input speed V3 in Figure 5 is PS. In the above example, the defuzzification constants for the conclusion are -4% for NS, 0% for ZR, and +4% for PS. This state is the state of pattern No. 6 in FIG. 6, and while this state is maintained, the object P to be treated is put into the inlet 101a. 577One cycle of operation is repeated, in which the material P to be treated is fed into the feed port 101b at a rate of 680 kg / h for 1200 seconds, and then the material P to be treated is fed into the feed port 101c at a rate of 770 kg / h for 1200 seconds. Note that FIG. 6 only shows the feeding speeds derived when the product temperatures T1 to T3 have a fitness of 1.0 for each label in the membership function. As mentioned above, in this embodiment, the defuzzification constants are set to NS = -4%, ZR = 0%, and PS = +4%, but these can be changed as appropriate depending on the configuration of the horizontal continuous conduction heat transfer dryer 1 and the properties of the workpiece P.

[0047] The throw-in speeds from each of these throw-in ports 101a to 101c are all integers, but this is because the decimal points have been rounded off, and for the sake of convenience, FIG. 6 also shows these rounded values. While the state of Pattern No. 6 continues, the materials P to be treated are fed from the respective feeding ports 101a to 101c at the feeding speed and for the time described above. I'll Thus, the discharge of the material P from the supply hopper 2 and the transport on the supply conveyor 12 are controlled. Even if the product temperatures T1 to T3 change from the "reference state" to the state of pattern No. 6 in this way, by setting the feeding speeds from the respective feeding ports 101a to 101c to the feeding speeds shown in pattern No. 6, the material P can be discharged as a dried product D with a constant moisture content from the discharge port 107a without causing adhesion to the multi-tubular heating tube 11 or excessive drying.

[0048] Next, as an example of a state not shown in Figure 6, we will explain the case where product temperature T1 is 74°C, product temperature T2 is 88.4°C, and product temperature T3 is 90°C (a state in which only product temperature T2 has changed from the state described as pattern No. 6 above). When the product temperature T2 is 88.4°C, the graph in Figure 4-2 shows that the attribute is ZR with a fitness of 0.4, and the attribute is PL with a fitness of 0.2. In this case, according to the fuzzy inference rules in Figure 5, the singleton of ZR for product temperature T2 is 680 kg / h and the singleton of PS is 707 kg / h, so based on the compatibility and singletons mentioned above, the fuzzy inference conclusion for product temperature T2 is 689 kg / h (rounded to the nearest integer). That is, the product temperature T1 74 While the conditions of temperature T1 of 88.4°C, product temperature T2 of 88.4°C, and product temperature T3 of 90°C are maintained, the feeding rate from feeding inlet 101a is set to 557 kg / h, the feeding rate from feeding inlet 101b is set to 689 kg / h, and the feeding rate from feeding inlet 101c is set to 770 kg / h, are repeated. Even if the product temperatures T1 to T3 change from the "reference state" to the above-mentioned temperatures in this way, by supplying the material P to be treated into the main body shell 10 at the above-mentioned feeding speed, the material P to be treated can be discharged from the discharge port 107a as a dried product D with a constant moisture content without causing adhesion to the multi-tubular heating tube 11 or excessive drying of the material P to be treated.

[0049] Other Examples The present invention has been described with reference to the above-mentioned embodiments, but the following modifications are within the scope of the technical concept of the present invention. Na Change conduct It is also possible. First, a modified example of the horizontal continuous conduction heat transfer dryer 1 will be described. 。 Inlet 101 is 2 pieces It is sufficient to have more than one inlet 101, and the larger the horizontal continuous conduction heat transfer dryer 1 that can process a larger amount of material P, the more inlets 101 should be provided to obtain a dried product D with stable moisture content. 3, the carrier gas port 103 may be provided on the rear side of the main body shell 10, and the exhaust port 104 may be provided on the front side of the main body shell 10.

[0050] Furthermore, in the present invention, the input speed is used as the result of fuzzy control, but the weight or volume of the object P to be treated may be used as the result of fuzzy control, and these weights or volumes may be used as the direct control targets. [Explanation of symbols]

[0051] 1. Horizontal continuous conduction heat transfer dryer 10 Main body shell 101 Inlet 101a Inlet 101b Inlet 101c Inlet 102 Overflow outlet 102b Board material 103 Carrier gas port 104 Exhaust port 105 Steam supply port 106 Drain port 107 Duct 107a Outlet 108 Rotary Valve 109 Probe insertion tube 109a Probe insertion tube 109b Probe insertion tube 109c Probe insertion tube 11 Multi-tube heating tube 111 Angle 112 Headboard 113 Axial Body 114 Bearing Block 115 rotary joint 115a rotary joint 115b rotary joint 116 Heat tube bundle 117 Lifter 118 Feed feather 12 Supply conveyor 120 Trough 121 Screw 122 Outlet 122a Outlet 122b Outlet 122c outlet 123 Supply pipe 123a Supply pipe 123b Supply pipe 123c supply pipe 124 Input damper 124a Input damper 124b Input damper 124c Input Damper 125 Inlet 13 Temperature Sensor 13a Temperature sensor 13b Temperature sensor 13c Temperature Sensor 2 Supply hopper 21 Hopper section 22 Screw conveyor section 23 Screw 25 load cells D Dry product F machine frame INV2 inverter INV3 inverter P Processing object P1 Intermediate product M1 motor M2 motor M3 motor WIC discharge weight controller

Claims

1. A shaft having a heat transfer member is disposed in the main body shell, and the shaft is rotated while heating steam is passed through the shaft. A horizontal continuous conduction heat transfer dryer in which a workpiece is placed in the main shell, and the workpiece is brought into contact with a heat transfer member that rotates together with the shaft while remaining in the main shell, thereby obtaining a dried product of the workpiece, A method for operating a horizontal continuous conduction heat transfer dryer having a main body shell with multiple inlets formed in the upper part of the main body shell, an overflow outlet provided at the rear of the main body shell, and temperature sensors disposed within the main body shell below and behind each inlet, The measured values ​​of the product temperatures by the temperature sensors arranged in the main body shell are used as condition parts, A method for operating a horizontal continuous conduction heat transfer dryer, characterized by performing fuzzy inference with the input speed of the materials to be treated input from each of the input ports as a conclusion.

2. 2. A method for operating a horizontal continuous conduction heat transfer dryer according to claim 1, wherein when the material to be treated is being fed through one of the feed ports, the material to be treated is not being fed through the other feed ports.

3. 3. The method for operating a horizontal continuous conduction heat transfer dryer according to claim 1, wherein the materials are introduced into the respective inlets in a predetermined order.

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