Dehydration control system, control device, and processing system

Abstract

In a system that performs both dehydration and solubilization of a material to be processed, this invention provides a technology that enables control of the water content of the material after dehydration. [Solution] The dewatering control system comprises a dewatering device for dewatering a workpiece and a control device that controls the operation of the dewatering device to adjust the moisture content of the workpiece. The control device compares an estimated amount of steam required to perform a solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, with the actual amount of steam required for the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result.

Description

Technical Field

[0001] The present disclosure relates to a dehydration control system, a control device, and a processing system.

Background Art

[0002] As a method for treating a workpiece containing organic components (for example, wastewater containing sludge), for example, a digestion treatment using anaerobic organisms is known. Before performing this digestion treatment, solubilization treatment may be performed on the dehydrated workpiece. In the solubilization treatment, for example, the solids contained in the workpiece are hydrolyzed by heating and pressurizing the workpiece using high-temperature steam. The amount of steam required for the solubilization treatment depends on the water content of the workpiece after dehydration.

[0003] Regarding the water content of the workpiece, for example, Patent Document 1 and Patent Document 2 disclose techniques for controlling the water content of sludge after dehydration in a dehydrator.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a system that performs dehydration treatment and solubilization treatment on a workpiece, it is desired to control the water content of the workpiece after dehydration.

Means for Solving the Problems

[0006] The dewatering control system in this disclosure comprises a dewatering device for dewatering a workpiece, and a control device for adjusting the moisture content of the workpiece by controlling the operation of the dewatering device. The control device compares an estimated amount of steam required to perform the solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, with an actual measured amount of steam required for the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result. [Effects of the Invention]

[0007] According to the technology disclosed herein, in a system that performs dehydration and solubilization of a material to be processed, it becomes possible to control the water content of the material after dehydration. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a diagram illustrating the configuration of a processing system 100 according to an embodiment. [Figure 2] Figure 2 is a diagram illustrating the hardware configuration of the control device 6 according to the embodiment. [Figure 3] Figure 3 is a block diagram illustrating the functional configuration of the control device 6 according to this embodiment. [Figure 4] Figure 4 is a flowchart illustrating the dewatering control by the control device 6 according to this embodiment. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described below with reference to the drawings. However, this description should not be interpreted as limiting, and will not limit the subject matter described in the claims. Furthermore, various changes, substitutions, and modifications can be made without departing from the spirit and scope of this disclosure. Different embodiments can also be combined as appropriate.

[0010] Furthermore, the following describes an application of the technology described herein to a sewage treatment facility, but the scope of application of the technology described herein is not limited to this. Also, in the embodiments described below, sludge containing organic components is used as the material to be treated, but the scope of treatment of the technology described herein is not limited to this.

[0011] [Processing System 100] Figure 1 is a diagram illustrating the configuration of a treatment system 100 according to an embodiment. The treatment system 100 is incorporated, for example, into a sewage treatment facility to treat sludge. Hereinafter, the treatment system 100 will be described assuming that the material to be treated is sludge.

[0012] The processing system 100 in this embodiment, as shown in Figure 1, includes, for example, a storage tank 1, a dewatering device 2, a solubilizing device 3, a digester tank 4, a dewatering device 5, a control device 6, a flow meter S1, a thermometer S2, a thermometer S3, and a flow meter S4. Hereinafter, the flow meter S1, thermometer S2, thermometer S3, and flow meter S4 will be collectively referred to simply as sensors. Furthermore, the configuration of the processing system 100 that includes the dewatering device 2, the control device 6, and sensors S1 to S4 will also be referred to as the dewatering control system 10.

[0013] [Storage Tank 1] Storage tank 1 stores, for example, primary sludge discharged from a primary sedimentation tank (not shown) in a sewage treatment facility, excess sludge discharged from a final sedimentation tank (not shown), or mixed raw sludge obtained by mixing primary sludge and excess sludge. Hereinafter, primary sludge, excess sludge, and mixed raw sludge will be collectively referred to simply as sludge.

[0014] The sludge stored in storage tank 1 is supplied to dewatering device 2 via line L1 by a pump (not shown) or the like.

[0015] [Dehydration device 2] Dewatering device 2 dewaters the sludge supplied from storage tank 1. Dewatering device 2 is an example of a "dewatering device" according to this disclosure.

[0016] As the dehydration device 2, for example, various forms of dehydrators such as a belt press type, a centrifugal separation type, a screw press type, etc. can be adopted, and the type is not particularly limited.

[0017] Hereinafter, the sludge dehydrated by the dehydration device 2 is also referred to as dehydrated sludge (the object to be treated after dehydration). As shown in FIG. 1, the dehydrated sludge is discharged from the dehydration device 2 by a pump (not shown) etc. through, for example, line L2, and is supplied to the solubilization device 3. Further, the dehydrated filtrate separated from the sludge is discharged from the dehydration device 2 by a pump (not shown) etc. through, for example, the return line L3, and is returned as return water to the upstream equipment (such as the primary sedimentation tank).

[0018] [Solubilization device 3] The solubilization device 3 performs a solubilization treatment with steam under a predetermined condition (hereinafter, also simply referred to as a predetermined condition) which is at least one of a predetermined temperature condition and a predetermined pressure condition on the sludge (dehydrated sludge) supplied from the dehydration device 2. The solubilization device 3 has, for example, a container 3a for accommodating the dehydrated sludge supplied from the dehydration device 2. The solubilization device 3 heats and pressurizes the sludge in the container 3a with high-temperature steam supplied from an external supply source (not shown) through line L4, thereby performing thermal hydrolysis of the solid content contained in the dehydrated sludge. The hydrothermal reaction in the thermal hydrolysis promotes the solubilization of the sludge. Then, the solubilized sludge is supplied from the solubilization device 3 to the digestion tank 4 by a pump (not shown) etc. through, for example, line L5. The operation mode of the solubilization device 3 may be a continuous type or a batch type.

[0019] Here, the predetermined temperature condition is, for example, the temperature condition of the sludge after temperature rise in the solubilization treatment. The predetermined pressure condition is, for example, the saturated steam pressure condition in the container 3a of the solubilization device 3. Also, for example, based on the relationship between temperature and pressure in saturated steam, one of the temperature condition and the pressure condition can be derived from the other.

[0020] [Digestion tank 4] The digester 4 digests, for example, the organic components contained in the sludge solubilized by the solubilizer 3. The digester 4 has, for example, an agitation function. In the digester 4, for example, the organic components contained in the sludge supplied from the solubilizer 3 are anaerobically digested (decomposed) by anaerobic bacteria in the digester 4. And digestion gas is generated in the process of this digestion. And the digested liquid digested in the digester 4 is supplied from the digester 4 to the dehydrator 5 by a pump (not shown) or the like via the line L6. The digester 4 is an example of the "digestion device" according to the present disclosure.

[0021] In the treatment system 100, for example, a flocculant for aggregating the solid content (organic matter) contained in the digested liquid flowing through the line L6 to form flocs is added. Also, for example, dilution water may be supplied to the sludge flowing through the line L5 to reduce the solid concentration. Further, the treatment system 100 may include any temperature adjustment means for adjusting the temperature of the sludge supplied to the digester 4. For example, a cooler (not shown) may be arranged between the solubilizer 3 and the digester 4 to cool the sludge supplied to the digester 4. Also, a heat exchanger (not shown) for heating the sludge in the digester 4 with a fluid (for example, warm water, etc.) supplied from an external heat source (not shown) may be arranged.

[0022] [Dehydrator 5] The dehydrator 5 dehydrates, for example, the sludge contained in the digested liquid supplied from the digester 4. And the dehydrated sludge is supplied from the dehydrator 5 to downstream equipment such as an incinerator by a pump (not shown) or the like. Also, the dehydrated filtrate separated from the sludge by the dehydrator 5 is returned as return water from the dehydrator 5 to upstream equipment (such as the primary sedimentation tank) by a pump (not shown) or the like.

[0023] [Sensors S1 to S4] A flow meter S1 is installed, for example, in line L2 and measures the amount of dewatered sludge supplied from the dewatering device 2 to the solubilizing device 3 (i.e., the amount of dewatered sludge input to the solubilizing device 3). A thermometer S2 is installed, for example, in line L2 and measures the temperature of the dewatered sludge input to the solubilizing device 3. A thermometer S3 is installed, for example, inside the container 3a of the solubilizing device 3 and measures the temperature inside the container 3a (i.e., the temperature of the dewatered sludge inside the solubilizing device 3). A flow meter S4 is installed, for example, in line L4 and measures the amount of steam supplied to the solubilizing device 3 (steam volume).

[0024] In the solubilization process using the solubilization device 3, for example, the temperature of the dewatered sludge inside the solubilization device 3 is measured by a thermometer S3, and the amount of steam supplied to the solubilization device 3 is adjusted so that the temperature of the dewatered sludge inside the solubilization device 3 reaches a target temperature (also called the target temperature) based on predetermined conditions. In other words, the amount of steam supplied is adjusted so that the measured temperature of the dewatered sludge approaches the target temperature. Alternatively, instead of the thermometer S3, a pressure gauge (not shown) may be installed inside the container 3a of the solubilization device 3. In that case, during the solubilization process, the pressure inside the solubilization device 3 is measured by the pressure gauge, and the amount of steam supplied to the solubilization device 3 is adjusted so that the pressure inside the solubilization device 3 reaches a target pressure (also called the target pressure) based on predetermined conditions.

[0025] [Control device 6] The control device 6 adjusts the moisture content of the dewatered sludge by, for example, controlling the dewatering device 2 (dewatering control). Specifically, the control device 6 performs dewatering control so that the moisture content of the dewatered sludge approaches a target value. The target value for the moisture content of the dewatered sludge is set to a value that minimizes the combined operating cost of the dewatering device 2 and the solubilizing device 3.

[0026] [Hardware configuration of control device 6] Figure 2 is a diagram illustrating the hardware configuration of the control device 6 according to the embodiment. As shown in Figure 2, the control device 6 is, for example, an electronic device having an electronic circuit. More specifically, the control device 6 is a computer device having, for example, a CPU 601 which is a processor, a memory 602, a communication device 603, and a storage medium 604. Each part is connected to the others via, for example, a bus 605.

[0027] The storage medium 604 has, for example, a program storage area (not shown) for storing a program 610 for performing dehydration control and other arbitrary information. The storage medium 604 also has, for example, an information storage area 620 for storing information used when performing dehydration control. The storage medium 604 may be, for example, an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0028] The CPU 601 performs model predictive control processing, for example, by executing a program 610 loaded into memory 602 from storage medium 604.

[0029] The communication device 603 accesses, for example, an operating terminal (not shown) where an operator inputs necessary information via a network (not shown), such as the Internet.

[0030] The electronic circuitry of the control device 6 may be, for example, an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit). The dehydration control process may also be performed, for example, on the FPGA or ASIC.

[0031] [Functions of Control Device 6] Figure 3 is a block diagram illustrating the functional configuration of the control device 6 according to the embodiment. The control device 6 includes, for example, an information acquisition unit 61, a storage unit 62, a calculation unit 63, and a control unit 64. The control device 6 realizes various functions, including the information acquisition unit 61, the storage unit 62, the calculation unit 63, and the control unit 64, through the organic cooperation of hardware such as a CPU 601 and memory 602 and a program.

[0032] [Information acquisition unit 61] The information acquisition unit 61 acquires information from sensors S1 to S4, for example.

[0033] Specifically, the information acquisition unit 61 acquires, for example, the measured amount of dewatered sludge input to the solubilization device 3 from the flow meter S1. More specifically, the information acquisition unit 61 acquires, for example, the measured amount of dewatered sludge to be subjected to solubilization treatment from the flow meter S1.

[0034] Furthermore, the information acquisition unit 61 acquires, for example, the temperature of the dewatered sludge fed into the solubilization device 3 from the thermometer S2. More specifically, the information acquisition unit 61 acquires, for example, the temperature of the dewatered sludge before the temperature rise due to the solubilization treatment from the thermometer S2.

[0035] Furthermore, the information acquisition unit 61 measures the temperature of the dewatered sludge in the solubilization device 3, for example, from the thermometer S3. More specifically, the information acquisition unit 61 acquires the measured temperature of the dewatered sludge after heating due to the solubilization treatment carried out according to predetermined conditions, for example, from the thermometer S3.

[0036] Furthermore, the information acquisition unit 61 acquires, for example, the measured amount of steam supplied to the solubilization device 3 from the flow meter S4. More specifically, the information acquisition unit 61 acquires, for example, the measured amount of steam required (actually used) in the solubilization process under predetermined conditions from the flow meter S4. Hereinafter, the measured amount of steam required in the solubilization process will also be referred to as the measured amount of steam.

[0037] [Storage section 62] The memory unit 62 is implemented, for example, by an information storage area 620, and stores various types of information. Specifically, the memory unit 62 stores, for example, information acquired by the information acquisition unit 61 from sensors S1 to S4 and setting values ​​used in calculations by the calculation unit 63 described later.

[0038] [Calculation section 63] The calculation unit 63 calculates, for example, an estimated value of the amount of steam required for solubilization treatment. Specifically, the estimated value of the amount of steam calculated by the calculation unit 63 is, for example, the amount of steam estimated to be required to solubilize dewatered sludge under predetermined conditions (at least one of predetermined temperature conditions and predetermined pressure conditions) when the water content of the dewatered sludge is at a target value. Hereinafter, the estimated value of the amount of steam required for solubilization treatment will also be referred to as the estimated amount of steam.

[0039] The calculation unit 63 calculates the estimated steam amount based, for example, on various measured values ​​obtained by the information acquisition unit 61 and predetermined set values ​​related to the sludge and the solubilization device 3.

[0040] Specifically, the calculation unit 63 uses the following as measured values, for example, the measured amount of dewatered sludge input in the solubilization treatment, the measured temperature of the dewatered sludge before heating in the solubilization treatment, and the measured temperature of the dewatered sludge after heating in the solubilization treatment, all acquired by the information acquisition unit 61, to calculate the estimated steam amount. Set values ​​may be used for the input amount of dewatered sludge and the temperature before heating. In addition, a target temperature (set value) based on predetermined conditions may be used for the temperature of the dewatered sludge after heating.

[0041] Furthermore, the calculation unit 63 may use the measured pressure inside the solubilizer 3 before and after pressurizing the dewatered sludge in the solubilization treatment instead of the measured temperature of the dewatered sludge before and after heating in the solubilization treatment. In this case, for example, a pressure gauge (not shown) may be installed in the container 3a of the solubilizer 3, and the pressure inside the solubilizer 3 before and after pressurizing in the solubilization treatment may be measured by the pressure gauge, and the measured pressure may be obtained by the information acquisition unit 61. The calculation unit 63 may use, for example, at least one of the measured pressure inside the solubilizer 3 before pressurizing the dewatered sludge and the measured pressure inside the solubilizer 3 after pressurizing the dewatered sludge to calculate the estimated amount of steam based on predetermined conditions in the solubilization treatment. In this case, the calculation unit 63 may derive (convert) the temperature of the dewatered sludge before heating based on the measured pressure inside the solubilizer 3 before pressurizing, or derive (convert) the temperature of the dewatered sludge after heating based on the measured pressure inside the solubilizer 3 after pressurizing. Furthermore, the pressure inside the solubilization device 3 after the pressure increase may be a target pressure (set value) based on predetermined conditions.

[0042] Furthermore, the calculation unit 63 uses the following as set values ​​to calculate the estimated amount of steam: for example, the target value of the water content, the specific heat of the solids in the dewatered sludge, the specific heat of the water in the dewatered sludge, the heat dissipation rate of the solubilizer 3, and the specific enthalpy of the steam.

[0043] Furthermore, the heat dissipation rate of the solubilization device 3 is, for example, the heat dissipation rate of the container 3a in which the solubilization process is performed in the solubilization device 3. The calculation unit 63 may use a set value for the heat dissipation rate when calculating the estimated amount of steam, but it may also calculate the heat dissipation rate based on, for example, a measured value of the ambient temperature, a measured value of the surface temperature of the container 3a, and the emissivity, and use the calculated heat dissipation rate.

[0044] Here, L [kg] is the measured amount of dewatered sludge input in the solubilization treatment, T1 [°C] is the measured temperature of the dewatered sludge before heating in the solubilization treatment, W [%] is the target value of the water content (by weight), T2 [°C] is the measured temperature of the dewatered sludge after heating in the solubilization treatment, C1 [kJ / kg·°C] is the specific heat of the solids in the dewatered sludge, C2 [kJ / kg·°C] is the specific heat of the water in the dewatered sludge, and R [%] is the heat dissipation rate of the solubilization device 3.

[0045] Then, when the moisture content of the dewatered sludge is the target value W, the amount of heat required to raise the temperature of the dewatered sludge from a measured value T1 to a measured value T2, according to predetermined conditions which are at least one of predetermined temperature conditions and predetermined pressure conditions, is defined as Q [kJ]. In this case, Q can be expressed by, for example, the following equation (1).

number

[0046] Furthermore, if the specific enthalpy of water vapor is H [kJ / kg] and the estimated amount of steam is A' [kg], then the estimated amount of steam A' can be expressed by the following equation (2).

number

[0047] The calculation unit 63 calculates the estimated steam amount using, for example, equations (1) and (2) above.

[0048] [Control Unit 64] The control unit 64 compares, for example, the estimated steam amount calculated by the calculation unit 63 based on the target moisture content with the measured steam amount acquired by the information acquisition unit 61, and controls the operation of the dewatering device 2 based on the comparison result. Here, "control of the operation of the dewatering device 2" includes not only the control of the dewatering device 2 itself, but also the control of other devices involved in the operation of the dewatering device 2 (for example, the pump that supplies sludge to the dewatering device 2).

[0049] Specifically, the control unit 64 controls the operation of the dewatering device 2 to reduce the moisture content of the dewatered sludge (moisture content reduction control) when, for example, the actual steam amount is greater than the estimated steam amount and the difference between the estimated steam amount and the actual steam amount is greater than a predetermined threshold (hereinafter also referred to as the first threshold). In other words, if the estimated steam amount is A', the actual steam amount is A, and the first threshold is a1, the control unit 65 performs moisture content reduction control when A-A'>a1 (a1≧0). Here, the first threshold a1 may be 0. In other words, the control unit 65 may also perform moisture content reduction control when the actual steam amount is greater than the estimated steam amount (i.e., when A-A'>0).

[0050] Furthermore, the control unit 65 controls the operation of the dewatering device 2 to increase the moisture content of the dewatered sludge (moisture content increase control) if, for example, the measured steam amount is smaller than the estimated steam amount and the difference between the estimated steam amount and the measured steam amount is greater than a predetermined threshold (hereinafter also referred to as the second threshold). In other words, if the second threshold is a2, the control unit 65 performs moisture content increase control when A'-A>a2 (a2≧0). Here, the second threshold a2 may be 0. In other words, the control unit 65 may also perform moisture content increase control when the measured steam amount is smaller than the estimated steam amount (i.e., when A'-A>0).

[0051] The control unit 64 may, for example, perform at least one of the following: moisture content reduction control and moisture content increase control (i.e., both or just one of them).

[0052] The control unit 64 controls the decrease and increase of moisture content by, for example, adjusting the amount of the operating factors of the dewatering device 2. Here, the operating factors of the dewatering device 2 are selected from the operating parameters of the dewatering device 2 that have a relationship with the moisture content of the dewatered sludge. Specifically, the control unit 65 adjusts, for example, the amount of sludge supplied to the dewatering device 2 and the rate of addition of coagulant to the sludge in the dewatering treatment as operating factors for the dewatering device 2. Also, if the dewatering device 2 is a belt press type, the control unit 65 adjusts the processing amount per unit time according to the feed speed of the filter cloth belt of the dewatering device 2 and the clamping pressure of the filter cloth belt on the sludge as operating factors. Also, if the dewatering device 2 is a centrifugal separator type, the control unit 65 adjusts the rotation torque of the bowl or screw conveyor of the dewatering device 2 as operating factors. Furthermore, if the dewatering device 2 is of the screw press type, the control unit 65 adjusts the operating factors such as the sludge injection pressure into the dewatering device 2, the rotation speed of the screw of the dewatering device 2, or the position of the back pressure plate.

[0053] Furthermore, the control unit 64 may, for example, in moisture content reduction control and moisture content increase control, adjust the amount of the operating factor of the dewatering device 2 based on information (hereinafter also referred to as correspondence information) that shows the correspondence between the operating factor of the dewatering device 2 and the moisture content of the dewatered sludge. The correspondence information may, for example, be stored in advance in the memory unit 62, or it may be derived by the control device 6 based on information about the dewatering device 2 acquired by the information acquisition unit 61. In addition, the control unit 64 may, for example, use a prediction model that predicts the amount of the operating factor of the dewatering device 2 using the moisture content of the dewatered sludge as the control variable, and output the amount of the operating factor of the dewatering device 2. The prediction model may, for example, be a trained model that has been machine-learned to understand the relationship between the operating factor of the dewatering device 2 and the moisture content of the dewatered sludge.

[0054] [Dehydration control process] The dewatering control process by the control device 6 will be described below. Figure 4 is a flowchart illustrating the dewatering control by the control device 6 according to this embodiment. The dewatering control process is repeatedly performed at predetermined time intervals during the operation of the dewatering device 2 and the solubilizing device 3. In addition, the control device 6 may perform the dewatering control process for each cycle of the solubilization process, for example, when the solubilizing device 3 is operating in batch mode. The following description will focus on the case where the control device 6 performs both the moisture content reduction control and the moisture content increase control described above.

[0055] In dewatering control, first, the calculation unit 63 of the control device 6 calculates an estimated amount of steam (estimated steam amount A') required to perform solubilization treatment under predetermined conditions, based on, for example, the measured amount of dewatered sludge input, the measured temperature of the dewatered sludge before heating, the measured temperature of the dewatered sludge after heating, and the target value of the moisture content (step S11 in Figure 4).

[0056] Next, the information acquisition unit 61 of the control device 6 acquires the measured value of the amount of steam required in the solubilization process (measured amount of steam A) from the flow meter S4 (step S12 in Figure 4).

[0057] Note that steps S11 and S12 may be performed in reverse order or in parallel.

[0058] Next, the control unit 64 of the control device 6 compares, for example, the estimated steam amount A' with the measured steam amount A and determines whether the conditions for starting the moisture content reduction control are met (step S13 in Figure 4). Specifically, the control unit 64 determines, for example, whether the measured steam amount A is greater than the estimated steam amount A' and whether the difference between the estimated steam amount A' and the measured steam amount A is greater than a predetermined first threshold a1.

[0059] For example, in step S13, if the start condition for moisture content reduction control is not met (step S13: NO), the control device 6 proceeds to step S14, and if the start condition for moisture content reduction control is met (step S13: YES), it proceeds to step S15.

[0060] In step S14, the control unit 64 compares, for example, the estimated steam amount A' with the measured steam amount A and determines whether the start condition for moisture content increase control is met (step S14 in Figure 4). Specifically, the control unit 64 determines, for example, whether the measured steam amount A is smaller than the estimated steam amount A' and whether the difference between the estimated steam amount A' and the measured steam amount A is greater than a predetermined second threshold a2.

[0061] If, for example, the start condition for moisture content increase control is not met in step S14 (step S14: NO), the control device 6 will not control the dewatering device 2 to adjust the moisture content and will complete the process (return to step S11). Alternatively, if, for example, the start condition for moisture content increase control is met in step S14 (step S14: YES), the control device 6 will proceed to step S16. If, for example, the start condition for moisture content increase control is not met in step S14 (step S14: NO), the control device 6 may return to step S13, for example.

[0062] In step S15, the control unit 64, for example, performs moisture content reduction control and controls the operation of the dewatering device 2 so that the moisture content of the dewatered sludge decreases (step S15 in Figure 4). The control device 6, for example, completes the process after step S15 (returns to step S11).

[0063] In step S16, the control unit 64, for example, performs moisture content increase control and controls the operation of the dewatering device 2 so that the moisture content of the dewatered sludge increases (step S15 in Figure 4). After step S16, the control device 6 completes the process (returns to step S11).

[0064] [Effects / Effects] As described above, the dewatering control system 10 according to the embodiment comprises a dewatering device 2 for dewatering sludge (material to be treated) and a control device 6 that controls the operation of the dewatering device 2 to adjust the moisture content of the dewatered sludge. The control device 6 compares an estimated amount of steam required to perform solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, when the moisture content of the dewatered sludge dewatered by the dewatering device 2 is set to a target value, with an actual amount of steam required for the solubilization treatment performed under the predetermined conditions (actual amount of steam), and controls the operation of the dewatering device 2 based on the comparison result.

[0065] In other words, in the dewatering control system 10 according to this embodiment, the control device 6 controls the operation of the dewatering device 2 based on the comparison result of the estimated amount of steam and the measured amount of steam, thereby controlling the water content of the dewatered sludge.

[0066] Here, for example, the amount of steam required for the solubilization treatment in the solubilization unit 3 downstream of the dewatering unit 2 depends on the water content of the dewatered sludge. Generally, since the specific heat of water is higher than the specific heat of the solids contained in the sludge, the amount of steam required for the solubilization treatment tends to increase as the water content of the dewatered sludge increases. Therefore, for example, if the measured amount of steam is greater than the estimated amount of steam, it can be determined that the water content of the dewatered sludge is greater than the target value, and conversely, if the estimated amount of steam is greater than the measured amount of steam, it can be determined that the water content of the dewatered sludge is less than the target value. For example, if the water content of the dewatered sludge is excessively high compared to the target value, excessive steam will be required for the solubilization treatment, resulting in extra energy being used in the solubilization unit 3. On the other hand, for example, if the water content of the dewatered sludge is less than the target value, the dewatering unit 2 will dewater the sludge more than necessary, resulting in extra energy and coagulant being used in the dewatering unit 2.

[0067] In contrast, the dewatering control system 10 according to this embodiment can reduce the amount of steam required for the subsequent solubilization treatment, the energy used in the dewatering device 2, and the amount of coagulant used by adjusting the water content of the dewatered sludge. As a result, energy savings can be achieved in the solubilization device 3 and the dewatering device 2. Furthermore, by adjusting the water content of the dewatered sludge and reducing fluctuations in water content, the operation of the solubilization device 3 can be stabilized.

[0068] Furthermore, the dewatering control system 10 according to this embodiment controls the operation of the dewatering device 2 based on a comparison between the estimated steam amount and the measured steam amount. For example, it can control the moisture content of dewatered sludge without using a moisture meter to measure the moisture content of the dewatered sludge. Therefore, the initial costs and maintenance costs required when using a moisture meter are eliminated, resulting in lower costs.

[0069] Furthermore, according to the dewatering control system 10 of this embodiment, the operation of the dewatering device 2 can be controlled by the control device 6, thereby enabling automated operation of the dewatering device 2. As a result, management costs such as labor costs in the operation of the dewatering device 2 can be reduced.

[0070] Furthermore, in this embodiment, if the measured steam amount is greater than the estimated steam amount and the difference between the estimated steam amount and the measured steam amount is greater than a predetermined first threshold, the control device 6 controls the operation of the dewatering device 2 so as to reduce the moisture content of the dewatered sludge. This makes it possible to bring the moisture content of the dewatered sludge closer to the target value if it is higher than the target value.

[0071] Furthermore, in this embodiment, if the measured steam amount is smaller than the estimated steam amount and the difference between the estimated steam amount and the measured steam amount is greater than a predetermined second threshold, the control device 6 controls the operation of the dewatering device 2 so as to increase the moisture content of the dewatered sludge. This makes it possible to bring the moisture content of the dewatered sludge closer to the target value if it is lower than the target value.

[0072] (Note) This disclosure includes the following aspects: [Aspect 1] A dewatering device for dewatering the material to be processed, The system includes a control device that adjusts the moisture content of the material to be processed by controlling the operation of the dewatering device, The control device compares an estimated amount of steam required to perform a solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, when the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result. Dehydration control system. [Aspect 2] The control device controls the operation of the dewatering apparatus so as to reduce the moisture content of the material to be processed when the measured value of the steam amount is greater than the estimated value of the steam amount and the difference between the estimated value of the steam amount and the measured value of the steam amount is greater than a predetermined threshold. Dehydration control system according to Embodiment 1. [Aspect 3] The control device controls the operation of the dewatering apparatus so as to increase the moisture content of the material to be processed when the measured value of the steam amount is smaller than the estimated value of the steam amount and the difference between the estimated value of the steam amount and the measured value of the steam amount is greater than a predetermined threshold. A dehydration control system according to embodiment 1 or 2. [Aspect 4] A control device that adjusts the moisture content of a workpiece by controlling the operation of a dewatering device that dewaters the workpiece, When the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, the estimated amount of steam required to perform the solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, is compared with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and the operation of the dewatering device is controlled based on the comparison result. Control device. [Aspect 5] A dewatering device for dewatering the material to be processed, A solubilizing device that performs a steam solubilization treatment on the material to be processed, which has been dehydrated by the dehydrating device, A digestion device for digesting organic components contained in the material to be processed, which have been solubilized by the solubilization device, The system includes a control device that adjusts the moisture content of the material to be processed by controlling the operation of the dewatering device, The control device compares an estimated amount of steam required to perform a solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, when the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result. Processing system. [Explanation of symbols]

[0073] 1: Storage tank 2: Dehydration device 3: Solubilization device 4: Digestion tank 5: Dehydration device 6: Control device 61: Information acquisition department 62: Storage part 63: Calculation Section 64: Control Unit 10: Dehydration control system 100: Processing System S1:Flowmeter S2: Thermometer S3: Thermometer S4:Flowmeter

Claims

1. A dewatering device for dewatering the material to be processed, The system includes a control device that adjusts the moisture content of the material to be processed by controlling the operation of the dewatering device, The control device compares an estimated amount of steam required to perform a solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, when the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result. Dehydration control system.

2. The control device controls the operation of the dewatering apparatus so as to reduce the moisture content of the material to be processed when the measured value of the steam amount is greater than the estimated value of the steam amount and the difference between the estimated value of the steam amount and the measured value of the steam amount is greater than a predetermined threshold. The dehydration control system according to claim 1.

3. The control device controls the operation of the dewatering apparatus so as to increase the moisture content of the material to be processed when the measured value of the steam amount is smaller than the estimated value of the steam amount and the difference between the estimated value of the steam amount and the measured value of the steam amount is greater than a predetermined threshold. The dehydration control system according to claim 1.

4. A control device that adjusts the moisture content of a workpiece by controlling the operation of a dewatering device that dewaters the workpiece, When the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, the estimated amount of steam required to perform the solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, is compared with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and the operation of the dewatering device is controlled based on the comparison result. Control device.

5. A dewatering device for dewatering the material to be processed, A solubilizing apparatus that performs a steam solubilization treatment on the material to be processed, which has been dehydrated by the dehydrating apparatus, A digestion device for digesting organic components contained in the material to be processed, which have been solubilized by the solubilization device, The system includes a control device that adjusts the moisture content of the material to be processed by controlling the operation of the dewatering device, The control device compares an estimated amount of steam required to perform a solubilization treatment under predetermined conditions, which are at least one of predetermined temperature and pressure conditions, when the moisture content of the material to be processed after dewatering by the dewatering device is set to a target value, with the measured amount of steam required in the solubilization treatment performed under the predetermined conditions, and controls the operation of the dewatering device based on the comparison result. Processing system.

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