JP6023383B1 - Control method of dehydration system - Google Patents

Abstract

In a dehydration system in which a concentrating device is arranged in front of a rotary pressure dehydrator, a method for suitably controlling the outlet pressure or main body load of the rotary pressure dehydrator is provided. Control of inlet pressure P1 for detecting a pressure deviation between a measured value of an inlet pressure P1 and a set value, and adjusting a filter rotational speed R to an optimum value based on the result, and a measured value of an outlet pressure P2 And the control of the outlet pressure P2 for adjusting the back pressure plate output M1 to the optimum value based on the result, and the back pressure plate output M1 is minimum. When the measured value of the outlet pressure P2 is higher than the set value, the set value of the dehydrator supply amount F2 is quantitatively adjusted positively, and the set value of the inlet pressure P1 is further adjusted to the dehydrator supply amount F2 after the positive adjustment. The inlet pressure P1 is updated so as to be an appropriate value. [Selection] Figure 1

Description

  The present invention relates to a control method for a dehydration system using a concentrator and a rotary pressure dehydrator.

  As a system for dehydrating a processing object such as sludge, a dehydration system in which a coagulation tank (flocculator), a concentrating device, and a dehydrator are arranged in series is known.

  There are various types of concentrators that constitute such a dehydration system. For example, as shown in Japanese Patent Application Laid-Open No. 2007-160161, a part of the processing object that has flowed into the casing is used. The inside of the casing is raised and filtered by a screen disposed in the upper half of the casing (the filtrate is allowed to flow out of the casing), so that the solid matter concentration in the processing object increases (the processing object is 2. Description of the Related Art A filtration concentration device, a granulation concentration device, and the like configured to be capable of being concentrated are known.

  In addition, there are various types of dehydrators. For example, as shown in Japanese Patent Application Laid-Open No. 2001-113109, liquid is contained in an annular (C-shaped) filter chamber formed around a rotation axis. Rotating pressure dehydration that introduces the processing object (processing stock solution) and rotates the two disk-shaped metal screens (filters) to advance the processing object forward and gradually apply pressure to perform dehydration Machines (rotary press filters) are known.

JP 2001-113109 A JP 2004-074066 A JP 2004-291036 A WO2005 / 0777848A1 WO2005 / 102495A1 WO2005 / 105263A1 JP 2006-341258 A JP 2007-326011 A JP 2007-160161 A

  As a control method for the rotary pressurization dehydrator, the inlet pressure is controlled by adjusting the screen rotation speed (filter rotation speed), or the outlet pressure is controlled by displacing the back pressure plate located near the cake outlet. However, if the outlet pressure is too high or too low, the outlet pressure may not be controlled well depending on the displacement of the back pressure plate or the like. is there.

  In addition, when the rotary pressure dehydrator is controlled alone, the above-mentioned problem may occur. However, this problem is caused by the dehydration system in which the concentrating device is arranged in the previous stage of the rotary pressure dehydrator. There is a possibility that it can be solved by coordinating with the control of the concentrator.

  The present invention relates to a dehydration system in which a concentrating device is disposed in front of a rotary pressure dehydrator, and by changing operating conditions related to the concentrator according to the situation of the rotary pressure dehydrator, the inlet pressure of the rotary pressure dehydrator is changed. It is another object of the present invention to provide a control method for a dehydration system that can suitably control the outlet pressure and the like.

  The dehydrating system control method according to the present invention (Claim 1) is directed to a dehydrating system in which a concentrating device is arranged in a preceding stage of a rotary pressurizing dehydrator. The shaft, inner spacer, outer spacer, deflector, and two metal screens fixed to both sides of the inner spacer, formed between the inner spacer, deflector and outer spacer from the stock solution supply port The processing object introduced into the annular filter chamber is advanced forward by rotating the two screens, and is gradually filtered and compressed by applying pressure, and the tip side is displaced in the horizontal direction. A back pressure plate is arranged on the side of the cake outlet and detects the pressure deviation between the measured value and the set value of the inlet pressure (P1) of the rotary pressure dehydrator. Control of the inlet pressure (P1) for adjusting the filter rotation speed (R) to an optimum value, and the pressure deviation between the measured value and the set value of the outlet pressure (P2) of the rotary pressurization dehydrator are detected, and the result is obtained. The control of the outlet pressure (P2) for adjusting the back pressure plate output (M1) to the optimum value is continuously executed, and the outlet pressure (P2) is measured in the state where the back pressure plate output (M1) is minimum. When the value is higher than the set value, the set value of the dehydrator supply amount (F2) is positively adjusted quantitatively, and the set value of the inlet pressure (P1) is further adjusted to the dehydrator supply amount (F2) after the positive adjustment. ) Is updated to an appropriate value for the inlet pressure (P1), and the inlet pressure (P1) is controlled based on the updated set value of the inlet pressure (P1) and the back pressure plate output The outlet pressure (P2) is controlled by adjusting (M1), and the back pressure plate output When the measured value of the outlet pressure (P2) is lower than the set value in a state where M1) is maximum, the set value of the dehydrator supply amount (F2) is negatively adjusted quantitatively, and the inlet pressure (P1) Is updated to be an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment, and based on the updated setting value of the inlet pressure (P1), Control of the inlet pressure (P1) is performed, and control of the outlet pressure (P2) by adjusting the back pressure plate output (M1) is performed.

  In this control method, the set value of the dehydrator supply amount (F2) is positively adjusted quantitatively, and the set value of the inlet pressure (P1) is further added to the dehydrator supply amount (F2) after the positive adjustment. After being updated so that the corresponding inlet pressure (P1) becomes an appropriate value, the outlet pressure (P2) is still higher than the set value, and the outlet pressure (P2) cannot be controlled by adjusting the back pressure plate output (M1). In this case, the set value of the dehydrator supply amount (F2) is again adjusted by a certain amount, and the set value of the inlet pressure (P1) is in accordance with the dehydrator supply amount (F2) after the positive adjustment again. The inlet pressure (P1) is updated to an appropriate value, the set value of the dehydrator supply amount (F2) is negatively adjusted, and the set value of the inlet pressure (P1) is dehydrated after the negative adjustment. Inlet pressure (P1) according to machine supply amount (F2) When the outlet pressure (P2) is still lower than the set value after being updated to an appropriate value and the outlet pressure (P2) cannot be controlled by adjusting the back pressure plate output (M1), the dehydrator is supplied again. The set value of the amount (F2) is negatively adjusted by a certain amount, and the set value of the inlet pressure (P1) is an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment again. It is preferable to be updated so that

  The dehydrating system control method according to the present invention (Claim 3) is intended for controlling a dehydrating system in which a concentrating device is arranged in front of a rotary pressurizing dehydrator. , Rotating shaft, inner spacer, outer spacer, deflector, and two metal screens fixed to both side surfaces of the inner spacer, between the inner spacer and deflector and outer spacer from the stock solution supply port The object to be treated introduced into the annular filter chamber formed in the above is configured to advance forward by rotating the two screens, and gradually compress and filter by applying pressure. A displacing vertical restrictor is arranged below the cake outlet, and further acts on the outer spacer and the like during operation of the rotary pressure dehydrator. A load cell for measuring the main body load load (K) is arranged, and a pressure deviation between the measured value of the inlet pressure (P1) of the rotary pressurization dehydrator and the set value is detected, and based on the result, the filter rotation speed (R ) To adjust the inlet pressure (P1) to the optimum value, and the load deviation between the measured value and set value of the main body load load (K) of the rotary pressurization dehydrator is detected, and the list is based on the result. Control of the main body load load (K) for adjusting the restrictor output (M2) to an optimum value is continuously executed, and the measured value of the main body load load (K) is obtained in a state where the restrictor output (M2) is minimum. When it is higher than the set value, the set value of the dehydrator supply amount (F2) is positively adjusted quantitatively, and the set value of the inlet pressure (P1) is further added to the dehydrator supply amount (F2) after the positive adjustment. It is updated to become the appropriate value of the corresponding inlet pressure (P1), this update The inlet pressure (P1) is controlled based on the set value of the inlet pressure (P1), and the body load (K) is controlled by adjusting the restrictor output (M2). When the measured value of the main body load load (K) is lower than the set value in the state where M2) is maximum, the set value of the dehydrator supply amount (F2) is quantitatively adjusted to be negative, and the inlet pressure (P1) ) Is updated so as to be an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the minus adjustment, and based on the updated setting value of the inlet pressure (P1). In addition, the inlet pressure (P1) is controlled, and the main body load load (K) is controlled by adjusting the restrictor output (M2).

  Also in this control method, the set value of the dehydrator supply amount (F2) is positively adjusted quantitatively, and the set value of the inlet pressure (P1) corresponds to the dehydrator supply amount (F2) after the positive adjustment. After being updated to an appropriate value for the inlet pressure (P1), the main body load load (K) is still higher than the set value, and the main body load load (K) cannot be controlled by adjusting the restrictor output (M2). In this case, the set value of the dehydrator supply amount (F2) is again adjusted by a certain amount, and the set value of the inlet pressure (P1) is in accordance with the dehydrator supply amount (F2) after the positive adjustment again. The inlet pressure (P1) is updated to an appropriate value, the set value of the dehydrator supply amount (F2) is negatively adjusted, and the set value of the inlet pressure (P1) is dehydrated after the negative adjustment. Inlet pressure (F2) After being updated to the appropriate value of 1), when the main body load load (K) is still lower than the set value and the main body load load (K) cannot be controlled by adjusting the restrictor output (M2), Again, the set value of the dehydrator supply amount (F2) is negatively adjusted by a certain amount, and further, the set value of the inlet pressure (P1) is changed to the inlet pressure (F2) after the negative adjustment is again made according to the dehydrator supply amount (F2). It is preferably updated so as to be an appropriate value of P1).

  In the above control method, when the pump is disposed between the concentrator and the rotary pressurizer and the set value of the dehydrator supply amount (F2) is adjusted to a plus value, the dehydrator supply amount (F2) is increased. In order to make the actual value coincide with the set value after the positive adjustment, adjustment is performed to increase the output (A2) of the pump between the concentrator and the rotary pressure dehydrator, or the opening of the filtrate valve of the concentrator When adjustment to reduce (B) is performed and the set value of the dehydrator supply amount (F2) is negatively adjusted, the actual value of the dehydrator supply amount (F2) is made to coincide with the set value after the negative adjustment. In addition, an adjustment to decrease the output (A2) of the pump between the concentrator and the rotary pressurizer is performed, or an adjustment to increase the opening (B) of the filtrate valve of the concentrator is performed. Also good.

  Further, when the set value of the dehydrator supply amount (F2) is positively adjusted, in order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the positive adjustment, the concentration device supply amount (F1) In order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the negative adjustment when the dehydrator supply amount (F2) is adjusted to be negative, the concentration is increased. Adjustment to reduce the apparatus supply amount (F1) may be performed.

  Furthermore, a densitometer is installed between the concentrator and the rotary pressure dehydrator, and this densitometer is placed under monitoring by the control means, and the concentrator supply amount (F1) is adjusted while observing changes in the measured value of the densitometer. You may make it raise or reduce the sludge density | concentration in concentrated sludge by adjusting.

  In addition, the turbidity of the filtrate discharged from the filtrate valve of the concentrator is monitored, and when an abnormality in the filtrate turbidity is detected, the dehydrator supply amount (F2) is forcibly increased by a certain amount, and / or Alternatively, it is preferable that an alarm be generated, or the turbidity of the filtrate discharged from the rotary pressurization dehydrator is monitored, and when an abnormality in the filtrate turbidity is detected, the dehydrator supply amount ( It is preferable to adjust the F2) to be decreased by a certain amount and to reduce the back pressure plate output (M1) or the restrictor output (M2) by a certain amount and / or to generate an alarm.

  According to the control method of the dehydrating system according to the present invention, the back pressure plate output (M1) or the list is increased because the outlet pressure (P2) or the main body load (K) of the rotary pressurizing dehydrator is too high or too low. Even in a situation where it is difficult to return the outlet pressure (P2) or the main body load load (K) to the set value by adjusting the output of the reactor (M2), the outlet pressure (F2) is adjusted to adjust the outlet pressure (F2). P2) or the main body load (K) can be suitably controlled.

FIG. 1 is a diagram showing an example of a dehydrating system to be controlled in the dehydrating system control method according to the first embodiment of the present invention. FIG. 2 is a diagram showing the internal structure of the rotary pressurization dehydrator 1 shown in FIG. FIG. 3 is a cross-sectional view of the rotary pressure dehydrator 1 along the line XX shown in FIG. FIG. 4 is a perspective view of the vicinity of the cake outlet 8 in the rotary pressure dehydrator 1 shown in FIG. FIG. 5 is a flowchart of the control method of the dehydration system according to the first embodiment of the present invention. FIG. 6 is a diagram illustrating an example of a dehydration system to be controlled in the control method according to the second embodiment of the present invention. FIG. 7 is a diagram showing the internal structure of the rotary pressurization dehydrator 1 to be controlled in the second embodiment of the present invention. FIG. 8 is a flowchart of the control method of the dehydration system according to the second embodiment of the present invention.

  Embodiments of the “dehydration system control method” of the present invention will be described below. FIG. 1 is a diagram illustrating an example of a dehydrating system to be controlled in the control method according to the first embodiment of the present invention. As shown in the figure, the control method according to the present invention is controlled by a dehydration system in which a concentrating device 53 is disposed in the previous stage of the rotary pressurization dehydrator 1.

  Specifically, the dehydrating system of FIG. 1 is configured by a first pump 51, a coagulation tank 52 (flocculator), a concentrating device 53, a second pump 55, a rotary pressurizing dehydrator 1, and control means (not shown). Has been. In addition, the code | symbol 54 shown in FIG. 1 is a valve | bulb (filtrate valve) for adjusting the quantity of the filtrate discharged | emitted from the concentration apparatus 53. FIG.

  In this dehydration system, the object to be treated (sludge in the present embodiment) is supplied from a supply source (sludge storage tank) (not shown) to the coagulation tank 52 by the first pump 51, and is tempered by adding and stirring the coagulant. (Prompt formation of agglomerated floc is promoted), and then agglomerated sludge (sludge in which agglomerated floc is formed) is sent from the agglomeration tank 52 to the concentrator 53. Then, the concentrated sludge (sludge concentrated by the concentrator 53) is sent from the concentrator 53 to the rotary pressure dehydrator 1 by the second pump 55 and dehydrated.

In FIG. 1, “F1” is the supply amount of the concentrator (the supply amount of sludge (m ³ / h) sent from the sludge storage tank to the concentrator 53 via the coagulation tank 52), and “F2” is the dehydration Supply amount (the supply amount (m ³ / h) of sludge (concentrated sludge) sent from the concentrator 53 to the rotary pressure dehydrator 1). “B” is the opening of the filtrate valve in the concentrator 53. The initial set value of the concentrator supply amount F1 is determined by the operator based on the processing performance of the concentrator 53, the equipment scale, the type and properties of sludge, the weather, and the like, and the initial set value of the dehydrator supply amount F2 Is determined according to the initial setting value of the concentration device supply amount F1 and other conditions, and is set before starting the dehydration system.

  FIG. 2 is a diagram showing the internal structure of the rotary pressure dehydrator 1, and FIG. 3 is a cross-sectional view of the rotary pressure dehydrator 1 along the line XX shown in FIG. The rotary pressure dehydrator 1 supplies a driving force to a rotary shaft 2, an inner spacer 3, an outer spacer 4, a deflector 5, two metal screens 6 (filters), a casing (not shown), and the rotary shaft 2. And a circular (C-shaped) filter chamber 9 (formed between the inner spacer 3 and the deflector 5 and the outer spacer 4 from the stock solution supply port 7, and has a rectangular cross section. And the object to be treated (sludge) is introduced into the space (from the stock solution supply port 7 to the cake outlet 8), and the rotating shaft 2 and the inner spacer 3 (fixed around the rotating shaft 2). , And by rotating the screen 6 (fixed to both sides of the inner spacer 3 respectively), the sludge is advanced forward, gradually pressure is applied and the filter is compressed, And it is configured to be able to discharge the dehydrated cake from rk in the outlet 8.

  As shown in FIG. 2, a back pressure plate 10 is installed at the cake outlet 8. The back pressure plate 10 is arranged on one side of the cake outlet 8 as shown in FIG. 4 (1), and the tip side is directed toward the facing casing 11a as shown in FIG. 4 (2). It is configured to be displaced toward (horizontal direction), reduce the opening area of the cake outlet 8, compress the sludge near the cake outlet 8, and increase the compressive force acting on the subsequent sludge. Yes. Such an operation of the back pressure plate 10 is realized by pressing the back pressure plate 10 toward the facing casing 11a by pressing means (not shown) arranged outside the back pressure plate 10.

  In this embodiment, as a pressing means, an air spring device (air) comprising a cylinder, a piston inserted in the cylinder, a push rod connected to the piston, an electropneumatic converter for supplying compressed air into the cylinder, and the like. Type actuator), and by adjusting the amount of compressed air supplied into the cylinder (electro-pneumatic converter output), the displacement of the push rod and the pressing force (back pressure plate output M1) can be adjusted. It has become.

  Further, a pressure sensor (not shown) is disposed inside the stock solution supply port 7 shown in FIG. 2 (inside the device). By this pressure sensor, the inlet pressure P1 (stock solution supply) when the rotary pressurization dehydrator 1 is operated. The in-machine pressure (kPa) in the vicinity of the mouth 7 is measured, and the measured value information is transmitted to the control means. In addition, a pressure sensor (not shown) is also arranged inside the cake outlet 8 (inside the machine). By this pressure sensor, the outlet pressure P2 (in the vicinity of the cake outlet 8) when the rotary dehydrator 1 is in operation. In-machine pressure (kPa)) is measured, and the measured value information is transmitted to the control means.

  The inlet pressure P1 has an “appropriate value” in relation to the dehydrator supply amount F2, the cake moisture content, and the SS recovery rate. Specifically, the cake moisture content and SS recovery rate of the rotary pressure dehydrator 1 are correlated with the inlet pressure P1, and the inlet pressure P1 includes the target value of cake moisture content and the target value of SS recovery rate. There are reasonable values to try to achieve. And the appropriate value of this inlet pressure P1 is fluctuate | varied according to the property of the sludge used as a process target, or the dehydrator supply amount F2. For this reason, when this type of rotary pressure dehydrator 1 is introduced, a trial run is performed, and an appropriate value of the inlet pressure P1 according to the dehydrator supply amount F2 (the target value of cake moisture content and SS) The value of the inlet pressure P1 that can achieve the target value of the recovery rate) is acquired.

  Also in this embodiment, an appropriate value of the inlet pressure P1 corresponding to the dehydrator supply amount F2 is obtained by performing a trial operation in advance on the rotary pressure dehydrator 1 for sludge to be actually processed. Data is acquired and stored in advance in the control means. At the start of the dehydrating system, an appropriate value of the inlet pressure P1 corresponding to the initial setting value of the dehydrator supply amount F2 is set as the initial setting value of the inlet pressure P1. On the other hand, the initial set value of the outlet pressure P2 is arbitrarily set by the operator according to the post-treatment method of the dewatered cake discharged from the rotary pressurizing dehydrator 1.

  FIG. 5 is a flowchart of the control method according to the first embodiment of the present invention. Control target items in this control method are an inlet pressure P1 and an outlet pressure P2 (see FIGS. 1 and 5). That is, when the dehydrating system shown in FIG. 1 is in operation, this control method is performed so that the inlet pressure P1 and the outlet pressure P2 coincide with the respective set values (so as to be within an allowable error range). Can be controlled.

  The control of the inlet pressure P1 in the dehydration system of FIG. 1 is performed as follows. First, the dehydration system is operated based on the initial set values (concentrator supply amount F1, dehydrator supply amount F2, each of the initial set values for the inlet pressure P1 and the outlet pressure P2, steps 101 to 104 in FIG. 5). In the state where the pressure deviation between the measured value of the inlet pressure P1 and the set value is detected and the measured value becomes higher than the set value as shown in the broken line 201 at the upper left in FIG. In this case, the output of the inverter that supplies power to the drive motor of the rotary shaft 2 is adjusted by the control means, and as a result, the filter rotation speed R is changed.

  For example, when the inlet pressure P1 increases due to some factor and becomes higher than the set value, the filter rotational speed R is adjusted to be large. When the filter rotation speed R increases, the moving speed of sludge (solid matter) in the filter chamber 9 increases, the amount of solid matter accumulated in the filter chamber 9 decreases, and as a result, the inlet pressure P1 decreases. On the other hand, when the inlet pressure P1 decreases due to some factor and becomes lower than the set value, the filter rotational speed R is controlled to be small.

  In this way, even if the inlet pressure P1 varies, the inlet pressure P1 is restored to the set value by adjusting the filter rotational speed R to an optimum value (FIG. 5). Step 105). Note that the optimum filter rotation speed R for keeping the inlet pressure P1 at the set value or returning it is determined based on the measured value of the inlet pressure P1 by the arithmetic processing unit of the control means (measured value and set value). Is detected (based on the result) (PID control).

  On the other hand, the control of the outlet pressure P2 is executed as follows. As shown in the broken line 202 on the upper right of FIG. 5, when the pressure deviation between the measured value of the outlet pressure P2 and the set value is detected and the measured value becomes higher than the set value, or when it becomes lower The output of the electropneumatic converter that supplies air to the cylinder of the air spring device is adjusted, and as a result, the back pressure plate output M1 is changed.

  For example, when the measured value of the outlet pressure P2 increases due to some factor and becomes higher than the set value, the back pressure plate output M1 is adjusted to be small. As described above, the back pressure plate 10 (see FIG. 4) is for compressing the sludge near the cake outlet 8 and for increasing the compressive force acting on the subsequent sludge. When the back pressure plate output M1 is reduced, The compressive force acting on the sludge is weakened, and the outlet pressure P2 is reduced. On the contrary, when the measured value of the outlet pressure P2 decreases due to some factor and becomes lower than the set value, the back pressure plate output M1 is adjusted to increase.

  As described above, even if the measured value of the outlet pressure P2 varies, the outlet pressure P2 is restored to the set value by adjusting the back pressure plate output M1 to an optimum value ( Step 106 in FIG. The back pressure plate output M1 (electropneumatic converter output of the air spring device) that is optimal for maintaining or returning the outlet pressure P2 to the set value is measured by the arithmetic processing unit of the control means. Based on the value (deviation between the measured value and the set value is detected, and based on the result) (PID control).

  The control of the inlet pressure P1 and the control of the outlet pressure P2 are continuously executed during operation of the dehydration system. However, there is a limit to the control of the outlet pressure P2 by adjusting the back pressure plate output M1 as described above. Specifically, when the outlet pressure P2 is higher than the set value, the back pressure plate output M1 is reduced to lower the outlet pressure P2, but as shown in FIG. In a state where the back pressure plate output M1 is minimum (a state where the opening area of the cake outlet 8 is hardly reduced and the back pressure plate 10 is not actively compressing sludge near the cake outlet 8), the outlet pressure P2 is If it is higher than the set value, the back pressure plate output M1 cannot be further reduced, and therefore the outlet pressure P2 cannot be lowered. On the contrary, in the state where the back pressure plate output M1 is the maximum, when the outlet pressure P2 is lower than the set value, the back pressure plate output M1 cannot be increased any more, so the outlet pressure P2 cannot be increased.

  The control method of this embodiment corresponds to the case where the outlet pressure P2 cannot be controlled by adjusting the back pressure plate output M1 as described above, by adjusting the dehydrator supply amount F2.

For example, when the measured value of the outlet pressure P2 is higher than the set value in the state where the back pressure plate output M1 is minimum (step 107), adjustment is performed so that the actual value of the dehydrator supply amount F2 increases. (Step 108). Specifically, the set value of the dehydrator supply amount F2 is positively adjusted quantitatively (for example, +1 m ³ / h).

  In the present embodiment, an adjustment to increase the second pump output A2 in order to match (increase) the actual value of the dehydrator supply amount F2 with the set value of the dehydrator supply amount F2 that has been positively adjusted. However, adjustment may be made to reduce the filtrate valve opening B (see FIG. 1). When the filtrate valve opening degree B is reduced, the amount of filtrate discharged from the concentrator 53 to the outside decreases, and this reduced amount flows to the second pump 55 side, so that the second pump output A2 is increased. As in the case of performing the above, the actual value of the dehydrator supply amount F2 can be increased.

  By the way, when the dehydrator supply amount F2 increases, the inlet pressure P1 also increases. At this time, the “set value of the inlet pressure P1” is “the inlet pressure corresponding to the dehydrator supply amount F2 before the increase”. Since the value is “appropriate value of P1,” it does not necessarily match the “appropriate value according to the dehydrator supply amount F2 after the increase”. Therefore, if it operates as it is, the inlet pressure P1 will be controlled to a value that deviates from the “appropriate value of the inlet pressure P1 according to the dehydrator supply amount F2 after the rise”. There is a possibility that the target value of the moisture content and the target value of the SS recovery rate in the dehydrated cake discharged from can not be achieved.

  Therefore, in this embodiment, when the set value of the dehydrator supply amount F2 is quantitatively adjusted in step 108, the set value of the inlet pressure P1 is “the inlet pressure corresponding to the dehydrator supply amount F2 after the increase”. (The set value of the inlet pressure P1 is updated) (step 109 in FIG. 5).

  Based on the updated set value as described above, the inlet pressure P1 is controlled (steps 105 and 201 in FIG. 5), and the outlet pressure P2 is controlled by adjusting the back pressure plate output M1 ( (Steps 106 and 202 in FIG. 5).

  The previous control of the outlet pressure P2 could not be executed because the measured value of the outlet pressure P2 was higher than the set value in the state where the back pressure plate output M1 was the minimum (FIG. 5). Step 107), the control of the outlet pressure P2 of this time is performed in a state where the dehydrator supply amount F2 is higher than the previous time, so there is a possibility that it can be executed.

  More specifically, when the dehydrator supply amount F2 is increased by increasing the second pump output A2 or by decreasing the filtrate valve opening B, it is discharged from the concentrator 53 to the outside. Since the reduced amount of the filtrate to be flowed to the second pump 55 side, the concentration (sludge concentration) of the concentrated sludge supplied to the rotary pressurization dehydrator 1 via the second pump 55 (the concentration of solids in the concentrated sludge) ) Will decrease. When the sludge concentration supplied to the rotary pressure dehydrator 1 decreases, the degree of sludge dewatering in the filter chamber 9 (see FIG. 2) decreases, and as a result, the outlet pressure P2 decreases, and the outlet pressure P2 is reduced. There is a possibility that it can be controlled within the range that can be controlled by adjusting the back pressure plate output M1.

  When the control of the outlet pressure P2 by adjusting the back pressure plate output M1 is successful (when the measured value can be matched with the set value), the control of the inlet pressure P1 is continued while maintaining the condition. And the control of the outlet pressure P2 is continuously executed. Conversely, if the outlet pressure P2 is still higher than the set value even if the dehydrator supply amount F2 is increased by a certain amount, and the outlet pressure P2 cannot be controlled by adjusting the back pressure plate output M1 (step 107), dehydration is performed again. The set value of the machine supply amount F2 is positively adjusted by a certain amount, and the adjustment is made to increase the set value of the inlet pressure P1 accordingly (steps 108 and 109), and finally the outlet by adjusting the back pressure plate output M1. Steps 108 and 109 are repeatedly executed until the pressure P2 can be controlled. As a result, the control of the outlet pressure P2 can be achieved.

On the other hand, when the measured value of the outlet pressure P2 is lower than the set value in the state where the back pressure plate output M1 is maximum (step 110), adjustment is performed such that the actual value of the dehydrator supply amount F2 is reduced. (Step 111). Specifically, the set value of the dehydrator supply amount F2 is negatively adjusted quantitatively (for example, −1 m ³ / h).

  In the present embodiment, the second pump output A2 is adjusted to decrease in order to match (decrease) the actual value of the dehydrator supply amount F2 with respect to the set value of the dehydrator supply amount F2 that has been negatively adjusted. However, adjustment may be made to increase the filtrate valve opening B (see FIG. 1). Increasing the filtrate valve opening B increases the amount of filtrate discharged to the outside from the concentrator 53 and decreases the amount of concentrated sludge flowing to the second pump 55 side, so that the second pump output A2 is reduced. As in the case of performing the above, the actual value of the dehydrator supply amount F2 can be reduced.

  When the dehydrator supply amount F2 decreases, the actual value of the inlet pressure P1 also decreases. The “set value of the inlet pressure P1” at this time is “the inlet corresponding to the dehydrator supply amount F2 before the decrease”. Since it is “appropriate value of pressure P1”, it does not necessarily coincide with “appropriate value according to dehydrator supply amount F2 after reduction”. Therefore, if it operates as it is, the inlet pressure P1 will be controlled to a value that deviates from the “appropriate value of the inlet pressure P1 according to the dehydrator supply amount F2 after the decrease”. There is a possibility that the target value of the moisture content and the target value of the SS recovery rate in the dehydrated cake discharged from can not be achieved.

  Therefore, in the present embodiment, when the set value of the dehydrator supply amount F2 is negatively adjusted in step 111, the set value of the inlet pressure P1 is “the inlet pressure corresponding to the dehydrator supply amount F2 after being lowered”. (The set value of the inlet pressure P1 is updated) (step 112 in FIG. 5).

  Based on the updated set value as described above, the inlet pressure P1 is controlled (steps 105 and 201 in FIG. 5), and the outlet pressure P2 is controlled by adjusting the back pressure plate output M1 ( (Steps 106 and 202 in FIG. 5).

  The previous control of the outlet pressure P2 could not be executed because the measured value of the outlet pressure P2 was lower than the set value in the state where the back pressure plate output M1 was maximum (FIG. 5). In step 110), the control of the outlet pressure P2 this time is performed in a state where the dehydrator supply amount F2 is lower than the previous time, so there is a possibility that it can be executed.

  More specifically, when the dehydrator supply amount F2 is decreased by decreasing the second pump output A2 or by increasing the filtrate valve opening B, it is discharged from the concentrator 53 to the outside. Since the amount of water in the sludge flowing toward the second pump 55 is reduced by the amount of the filtrate to be increased, the concentration of the concentrated sludge supplied to the rotary pressure dehydrator 1 via the second pump 55 is reduced. Will rise. When the sludge concentration supplied to the rotary pressure dehydrator 1 increases, the degree of sludge dewatering in the filter chamber 9 (see FIG. 2) increases, and as a result, the outlet pressure P2 increases, and the outlet pressure P2 is reduced. There is a possibility that it can be controlled within the range that can be controlled by adjusting the back pressure plate output M1.

  When the control of the outlet pressure P2 by adjusting the back pressure plate output M1 is successful (when the measured value can be matched with the set value), the control of the inlet pressure P1 is continued while maintaining the condition. And the control of the outlet pressure P2 is continuously executed. Conversely, if the outlet pressure P2 is still lower than the set value and the outlet pressure P2 cannot be controlled by adjusting the back pressure plate output M1 (step 110) even if the dehydrator supply amount F2 is decreased by a certain amount, dehydration is performed again. The set value of the machine supply amount F2 is negatively adjusted by a certain amount, and the set value of the inlet pressure P1 is lowered accordingly (steps 111 and 112), and finally the outlet by adjusting the back pressure plate output M1. Steps 111 and 112 are repeatedly executed until the pressure P2 can be controlled. As a result, the control of the outlet pressure P2 can be achieved.

  Then, the control method of the dehydration system concerning a second embodiment of the present invention is explained. FIG. 6 is a diagram illustrating an example of a dehydration system to be controlled in the control method according to the second embodiment of the present invention. As shown in the figure, also in this embodiment, the dehydration system in which the concentrating device 53 is arranged in the previous stage of the rotary pressurization dehydrator 1 is a control target. The rotary pressure dehydrator 1 of the dehydration system to be controlled in this embodiment has the same basic configuration as the rotary pressure dehydrator (see FIG. 2) in the first embodiment, but in the vicinity of the cake outlet 8. The structure is slightly different.

  More specifically, as shown in FIG. 7, the rotary pressurization dehydrator 1 to be controlled in this embodiment introduces a treatment object (sludge) from the stock solution supply port 7 into the annular filter chamber 9. The sludge is advanced forward by rotating the rotary shaft 2, the inner spacer 3, and the screen 6, and is gradually filtered to compress the pressure, and the dehydrated cake can be discharged from the cake outlet 8. In this respect, it is common with the rotary pressure dehydrator (see FIG. 2) in the first embodiment.

  However, the back pressure plate 10 as shown in FIG. 2 is not arranged in the vicinity of the cake outlet 8, and instead, a vertical restrictor 12 as shown in FIG. 7 is arranged below the cake outlet 8. Yes. The vertical restrictor 12 is displaced in the vertical direction at the tip side, reduces the opening area of the cake outlet 8, compresses the sludge near the cake outlet 8, and increases the compressive force acting on the subsequent sludge. It is configured as follows.

  The operation of the vertical restrictor 12 is constituted by an air spring device (a cylinder, a piston inserted in the cylinder, a push rod 13 connected to the piston, an electropneumatic converter for supplying compressed air into the cylinder, and the like. And by adjusting the amount of compressed air supplied into the cylinder of the air spring device (electro-pneumatic converter output), the displacement amount and the pressing force ( The restrictor output M2) can be adjusted.

  Further, a pressure sensor (not shown) is disposed inside the stock solution supply port 7 shown in FIG. 2 (inside the device). By this pressure sensor, the inlet pressure P1 (stock solution supply) when the rotary pressurization dehydrator 1 is operated. The in-machine pressure (kPa) in the vicinity of the mouth 7 is measured, and the measured value information is transmitted to the control means.

  In addition, a column 14 is attached to the outer spacer 4, and a load cell 15 is attached to the column 14. When the rotary pressure dehydrator 1 is in operation, the rotational force of the inner spacer 3 and the screen 6 is transmitted to the main body (outer spacer 4 and the like) through the sludge introduced into the filter chamber 9. A force (load) for rotating in the same direction also acts on the outer spacer 4 and the like. In the rotary pressure dehydrator 1 of the present embodiment, the outer spacer 4 and the like are fixed by the support column 14 so that they are not rotated by the load, and the load cell 15 arranged in the middle of the column is used by the load cell 15. The main body load K is measured, and the measured value information is transmitted to the control means.

  The main body load load K measured by the load cell 15 during the operation of the rotary pressurization dehydrator 1 has a correlation (negative correlation) with the cake moisture content. When the cake moisture content is low, the main body load load K increases. When the moisture content of the cake is high, the main body load K is reduced. Further, when the vertical restrictor 12 is operated so that the opening of the cake outlet 8 is reduced (when the restrictor output M2 is increased), the main body load K is increased, and the vertical restrictor 12 is set so that the opening of the cake outlet 8 is enlarged. (When the restrictor output M2 is reduced), the main body load K is reduced. For this reason, the cake moisture content is controlled to a desired value by adjusting the output of the vertical restrictor 12 (restrictor output M2) so that the main body load K is an appropriate value in relation to the cake moisture content. can do.

  Note that the inlet pressure P1 has an “appropriate value” in relation to the dehydrator supply amount F2, the cake moisture content, and the SS recovery rate, and a trial run is performed, depending on the dehydrator supply amount F2. The data of the appropriate value of the inlet pressure P1 is acquired and set in advance in the control means, as in the first embodiment.

  FIG. 8 is a flowchart of the control method according to the second embodiment of the present invention. Control target items in this control method are the inlet pressure P1 and the main body load load K (see FIGS. 6 and 8). In other words, when the dehydrating system shown in FIG. 6 is in operation, by performing this control method, the inlet pressure P1 and the main body load load K are matched with the respective set values (so as to be within an allowable error range). ) Can be controlled.

  Control of the inlet pressure P1 in the dehydration system of FIG. 6 is performed in the same manner as in the first embodiment. That is, the dehydrating system is operated based on the initial setting values (concentrator supply amount F1, dehydrator supply amount F2, inlet pressure P1, and initial setting values for main body load load K, steps 301 to 304 in FIG. 8). In this state, as shown in the upper left broken line 401 in FIG. 8, a pressure deviation between the measured value of the inlet pressure P1 and the set value is detected, and based on the result, the inlet pressure P1 is set to the set value. In order to maintain or restore, the optimum filter rotation speed R is calculated by the arithmetic processing unit of the control means, the inverter output is adjusted, and the filter rotation speed R is adjusted to the optimum value, so that the inlet pressure P1 is The setting value is restored (step 305 in FIG. 8) (PID control).

  On the other hand, the control of the main body load K is performed as follows. As shown in the upper right broken line 402 in FIG. 8, when a load deviation between the measured value of the main body load load K and the set value is detected and the measured value becomes higher than the set value, or when it becomes lower. The output of the electropneumatic converter that supplies air to the cylinder of the air spring device is adjusted, and as a result, the restrictor output M2 is changed.

  For example, when the measured value of the main body load load K increases for some reason and becomes higher than the set value, the restrictor output M2 is adjusted to be small. As described above, the vertical restrictor 12 (see FIG. 7) is for compressing the sludge near the cake outlet 8 and for increasing the compressive force acting on the subsequent sludge, and when the restrictor output M2 is reduced. The compressive force acting on the sludge is weakened, and the main body load K is reduced. On the contrary, when the measured value of the main body load K is lowered due to some factor and becomes lower than the set value, the restrictor output M2 is adjusted to be increased.

  As described above, even if the measurement value of the main body load load K varies, the main body load load K returns to the set value by adjusting the restrictor output M2 to an optimum value. (Step 306 in FIG. 8). The restrictor output M2 (electro-pneumatic converter output of the air spring device) that is optimal for maintaining the main body load load K at the set value or returning the main body load load K is determined by the arithmetic processing unit of the control means. (PID control) is calculated based on the measured value (based on the result of detecting the deviation between the measured value and the set value).

  The control of the inlet pressure P1 and the control of the main body load load K are continuously executed during the operation of the dehydration system. However, there is a limit to the control of the main body load load K by adjusting the restrictor output M2 as described above. Specifically, when the main body load load K is higher than the set value, the restrictor output M2 is decreased to lower the main body load load K, but the restrictor output M2 is minimum. In a state where the opening area of the cake outlet 8 is hardly reduced and the vertical restrictor 12 is not actively compressing sludge in the vicinity of the cake outlet 8, the main body load load K is higher than the set value. In this case, the restrictor output M2 cannot be further reduced, and therefore the main body load K cannot be reduced. On the contrary, in the state where the restrictor output M2 is the maximum, when the main body load load K is lower than the set value, the restrictor output M2 cannot be increased any more, so the main body load load K may be increased. Can not.

  The control method of this embodiment corresponds to the case where the main body load load K cannot be controlled by adjusting the restrictor output M2, as described above, by adjusting the dehydrator supply amount F2.

For example, in a state where the restrictor output M2 is at a minimum, when the measured value of the main body load load K is higher than the set value (step 307), adjustment is performed so that the actual value of the dehydrator supply amount F2 increases. (Step 308). Specifically, the set value of the dehydrator supply amount F2 is positively adjusted quantitatively (for example, +1 m ³ / h).

  In the present embodiment, an adjustment to increase the second pump output A2 in order to match (increase) the actual value of the dehydrator supply amount F2 with the set value of the dehydrator supply amount F2 that has been positively adjusted. However, adjustment may be made to reduce the filtrate valve opening B (see FIG. 6). When the filtrate valve opening degree B is reduced, the amount of filtrate discharged from the concentrator 53 to the outside decreases, and this reduced amount flows to the second pump 55 side, so that the second pump output A2 is increased. As in the case of performing the above, the actual value of the dehydrator supply amount F2 can be increased.

  By the way, when the dehydrator supply amount F2 increases, the inlet pressure P1 also increases. At this time, the “set value of the inlet pressure P1” is “the inlet pressure corresponding to the dehydrator supply amount F2 before the increase”. Since the value is “appropriate value of P1,” it does not necessarily match the “appropriate value according to the dehydrator supply amount F2 after the increase”. Therefore, if it operates as it is, the inlet pressure P1 will be controlled to a value that deviates from the “appropriate value of the inlet pressure P1 according to the dehydrator supply amount F2 after the rise”. There is a possibility that the target value of the moisture content and the target value of the SS recovery rate in the dehydrated cake discharged from can not be achieved.

  Therefore, in the present embodiment, when the set value of the dehydrator supply amount F2 is quantitatively adjusted to be positive in step 308, the set value of the inlet pressure P1 is “inlet pressure corresponding to the dehydrator supply amount F2 after being increased”. (The set value of the inlet pressure P1 is updated) (step 309 in FIG. 8).

  The inlet pressure P1 is controlled based on the updated set value as described above (steps 305 and 401 in FIG. 8), and the main body load load K is controlled by adjusting the restrictor output M2. (Attempted) (steps 306 and 402 in FIG. 8).

  The previous control of the main body load load K could not be executed because the measured value of the main body load load K was higher than the set value when the restrictor output M2 was at a minimum ( The control of the main body load load K in FIG. 8 (step 307) is performed in a state where the dehydrator supply amount F2 is higher than the previous time, so there is a possibility that it can be executed.

  More specifically, when the dehydrator supply amount F2 is increased by increasing the second pump output A2 or by decreasing the filtrate valve opening B, it is discharged from the concentrator 53 to the outside. Since the reduced amount of the filtrate to be flowed to the second pump 55 side, the concentration (sludge concentration) of the concentrated sludge supplied to the rotary pressurization dehydrator 1 via the second pump 55 (the concentration of solids in the concentrated sludge) ) Will decrease. When the sludge concentration supplied to the rotary pressure dehydrator 1 decreases, the sludge dehydration degree in the filter chamber 9 (see FIG. 2) decreases, and as a result, the main body load load K decreases, and the main body load load There is a possibility that K can fall within a range that can be controlled by adjusting the restrictor output M2.

  Then, when the control of the main body load K by the adjustment of the restrictor output M2 is successful (when the measured value can be matched with the set value), the inlet pressure P1 is continuously maintained while maintaining the condition. The control and the control of the main body load load K are continuously executed. On the contrary, even if the dehydrator supply amount F2 is increased by a certain amount, when the main body load load K is still higher than the set value and the main body load load K cannot be controlled by adjusting the restrictor output M2 (step 307), Again, the set value of the dehydrator supply amount F2 is positively adjusted by a certain amount, and the setting value of the inlet pressure P1 is increased accordingly (steps 308 and 309), and finally the restrictor output M2 is adjusted. Steps 308 and 309 are repeatedly executed until the main body load load K can be controlled. As a result, control of the main body load load K can be achieved.

On the other hand, in the state where the restrictor output M2 is maximum, when the measured value of the main body load load K is lower than the set value (step 310), adjustment is performed so that the actual value of the dehydrator supply amount F2 decreases. (Step 311). Specifically, the set value of the dehydrator supply amount F2 is negatively adjusted quantitatively (for example, −1 m ³ / h).

  In the present embodiment, the second pump output A2 is adjusted to decrease in order to match (decrease) the actual value of the dehydrator supply amount F2 with respect to the set value of the dehydrator supply amount F2 that has been negatively adjusted. However, adjustment may be made to increase the filtrate valve opening B (see FIG. 6). Increasing the filtrate valve opening B increases the amount of filtrate discharged to the outside from the concentrator 53 and decreases the amount of concentrated sludge flowing to the second pump 55 side, so that the second pump output A2 is reduced. As in the case of performing the above, the actual value of the dehydrator supply amount F2 can be reduced.

  When the dehydrator supply amount F2 decreases, the actual value of the inlet pressure P1 also decreases. The “set value of the inlet pressure P1” at this time is “the inlet corresponding to the dehydrator supply amount F2 before the decrease”. Since it is “appropriate value of pressure P1”, it does not necessarily coincide with “appropriate value according to dehydrator supply amount F2 after reduction”. Therefore, if it operates as it is, the inlet pressure P1 will be controlled to a value that deviates from the “appropriate value of the inlet pressure P1 according to the dehydrator supply amount F2 after the decrease”. There is a possibility that the target value of the moisture content and the target value of the SS recovery rate in the dehydrated cake discharged from can not be achieved.

  Therefore, in the present embodiment, when the set value of the dehydrator supply amount F2 is quantitatively adjusted to be negative in step 311, the set value of the inlet pressure P1 is “the inlet pressure corresponding to the dehydrator supply amount F2 after being lowered”. (The set value of the inlet pressure P1 is updated) (step 312 in FIG. 8).

  The inlet pressure P1 is controlled based on the updated set value as described above (steps 305 and 401 in FIG. 8), and the main body load load K is controlled by adjusting the restrictor output M2. (Attempted) (steps 306 and 402 in FIG. 8).

  Note that the previous control of the main body load load K could not be executed because the measured value of the main body load load K was lower than the set value in the state where the restrictor output M2 was maximum ( The control of the main body load load K in step 310) in FIG. 8 is performed in a state where the dehydrator supply amount F2 is lower than the previous time, so there is a possibility that it can be executed.

  More specifically, when the dehydrator supply amount F2 is decreased by decreasing the second pump output A2 or by increasing the filtrate valve opening B, it is discharged from the concentrator 53 to the outside. Since the amount of water in the sludge flowing toward the second pump 55 is reduced by the amount of the filtrate to be increased, the concentration of the concentrated sludge supplied to the rotary pressure dehydrator 1 via the second pump 55 is reduced. Will rise. When the concentration of sludge supplied to the rotary pressure dehydrator 1 increases, the degree of sludge dewatering in the filter chamber 9 (see FIG. 2) increases, and as a result, the main body load load K increases and the main body load load increases. There is a possibility that K can fall within a range that can be controlled by adjusting the restrictor output M2.

  Then, when the control of the main body load K by the adjustment of the restrictor output M2 is successful (when the measured value can be matched with the set value), the inlet pressure P1 is continuously maintained while maintaining the condition. The control and the control of the main body load load K are continuously executed. On the other hand, even if the dehydrator supply amount F2 is decreased by a certain amount, the main body load load K is still lower than the set value and the main body load load K cannot be controlled by adjusting the restrictor output M2 (step 310). Again, the set value of the dehydrator supply amount F2 is negatively adjusted by a fixed amount, and the set value of the inlet pressure P1 is lowered accordingly (steps 311 and 312), and finally the restrictor output M2 is adjusted. Steps 311 and 312 are repeatedly executed until the main body load load K can be controlled. As a result, control of the main body load load K can be achieved.

  In the first embodiment and the second embodiment, when the back pressure plate output M1 or the restrictor output M2 is at a minimum, the measured value of the outlet pressure P2 or the main body load load K is higher than the set value. In the case (step 107 in FIG. 5, step 307 in FIG. 8), or when the back pressure plate output M1 or the restrictor output M2 is maximum, the measured value of the outlet pressure P2 or the main body load load K is lower than the set value. (Step 110 in FIG. 5, step 310 in FIG. 8) The dehydrator supply amount F2 is increased or decreased by a certain amount while the concentration device supply amount F1 (see FIGS. 1 and 6) is maintained at the initial setting value. (Steps 108 and 111 in FIG. 5 and Steps 308 and 311 in FIG. 8), but the concentrator supply amount F1 is managed by the control means (included in the control target). By increasing the concentrator supply amount F1 as appropriate when the dehydrator supply amount F2 needs to be increased and by decreasing the concentrator supply amount F1 as appropriate when the dehydrator supply amount F2 needs to be decreased, the dehydrator A situation in which it is difficult to control the outlet pressure P2 or the main body load load K by adjusting (increasing or decreasing) the supply amount F2 and adjusting the back pressure plate output M1 or the restrictor output M2 (steps 107 and 110 in FIG. 5, steps in FIG. 8). 307, 310).

  Further, a concentration meter (not shown) installed between the concentration device 53 and the rotary pressure dehydrator 1 is placed under monitoring by the control means, and the concentration device supply amount F1 is set while monitoring the change in the measured value of the concentration meter. By adjusting (increasing / decreasing), the sludge concentration (solid matter amount) in the concentrated sludge is appropriately increased or decreased, whereby the outlet pressure P2 or the main body load load K may be controlled depending on the adjustment of the back pressure plate output M1 or the restrictor output M2. It may be possible to cope with difficult situations (steps 107 and 110 in FIG. 5 and steps 307 and 310 in FIG. 8).

  Also, the turbidity of the filtrate discharged from the filtrate valve 54 (see FIGS. 1 and 6) of the concentrator 53 is monitored, and if an abnormality in the filtrate turbidity is detected, the dehydrator supply amount F2 is forcibly set. And / or an alarm (sending a message to the administrator, outputting a warning sound, and / or lighting or blinking of a warning light) may be performed. good.

  For example, when the control method of the first embodiment or the second embodiment is being executed, the adjustment (step 111 in FIG. 5 and step 311 in FIG. 8) for reducing the dehydrator supply amount F2 by a certain amount is repeatedly executed. Therefore, when the dehydrator supply amount F2 is too low, there is a concern that the turbidity of the filtrate discharged from the concentrating device 53 exceeds the reference value (becomes too turbid). Even if such a situation occurs, it can be handled automatically by the control means or by prompting human intervention.

  Further, the turbidity of the filtrate discharged from the rotary pressure dehydrator 1 is monitored, and when an abnormality in the filtrate turbidity is detected, the dehydrator supply amount F2 is forcibly decreased by a certain amount, and the back pressure plate. Control is performed to decrease the output M1 or the restrictor output M2 by a certain amount, and / or an alarm (display of a warning message, output of a warning sound, and / or lighting or blinking of a warning light) is generated. You may comprise.

  For example, when the control method of the first embodiment or the second embodiment is being executed, adjustments (step 111 in FIG. 5 and step 311 in FIG. 8) that reduce the dehydrator supply amount F2 by a certain amount were performed. Then, as a result of the adjustment (steps 106 and 202 in FIG. 5 and steps 306 and 402 in FIG. 8) that the back pressure plate output M1 or the restrictor output M2 is increased by the PID control, the rotary pressurization dehydrator 1 It is also assumed that the turbidity of the filtrate discharged from the plant will exceed the reference value (too much turbidity), but even if such a situation occurs, the control means automatically or by human intervention You can respond by prompting.

1: Rotary pressure dehydrator,
2: Rotating shaft,
3: Inner spacer,
4: Outer spacer,
5: Deflector,
6: Screen,
7: Stock solution supply port,
8: Cake exit,
9: Filter chamber
10: Back pressure plate,
11a, 11b: casing,
12: Vertical restrictor,
13: Push rod,
14: support,
15: Load cell,
51: First pump,
52: Coagulation tank
53: Concentrator,
54: Filtrate valve,
55: Second pump,
A1: First pump output,
A2: Second pump output,
B: Filtrate valve opening,
F1: Concentrator supply amount,
F2: Dehydrator supply amount,
K: body load
M1: back pressure plate output,
M2: restrictor output,
P1: Inlet pressure,
P2: outlet pressure,
R: Filter rotation speed

Claims (9)

A control method of a dehydration system in which a concentrating device is arranged in front of a rotary pressure dehydrator,
The rotary pressure dehydrator has a rotating shaft, an inner spacer, an outer spacer, a deflector, and two metal screens fixed to both side surfaces of the inner spacer, and the inner spacer and the deflector from the stock solution supply port. The object to be processed introduced into the annular filter chamber formed between the outer spacer and the outer spacer is advanced forward by rotating the two screens, and is gradually compressed by applying pressure and filtering. The back pressure plate whose tip side is displaced in the horizontal direction is arranged on the side of the cake outlet,
The pressure deviation between the measured value and the set value of the inlet pressure (P1) of the rotary pressurization dehydrator is detected, and the inlet pressure (P1) for adjusting the filter rotational speed (R) to the optimum value based on the result is detected. The pressure difference between the control and the measured value of the outlet pressure (P2) of the rotary pressurization dehydrator and the set value is detected, and the outlet pressure (M1) is adjusted to the optimum value based on the result. P2) is continuously executed,
When the measured value of the outlet pressure (P2) is higher than the set value in the state where the back pressure plate output (M1) is minimum, the set value of the dehydrator supply amount (F2) is quantitatively adjusted positively, The setting value of the pressure (P1) is updated so as to be an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the plus adjustment, and the setting value of the inlet pressure (P1) after this update Based on the control, the inlet pressure (P1) is controlled, and the outlet pressure (P2) is controlled by adjusting the back pressure plate output (M1).
When the measured value of the outlet pressure (P2) is lower than the set value in the state where the back pressure plate output (M1) is maximum, the set value of the dehydrator supply amount (F2) is quantitatively adjusted to be negative, The set value of the pressure (P1) is updated so as to be an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the minus adjustment, and the updated set value of the inlet pressure (P1) The control method for the dehydration system is characterized in that the control of the inlet pressure (P1) is performed and the control of the outlet pressure (P2) is performed by adjusting the back pressure plate output (M1). The set value of the dehydrator supply amount (F2) is quantitatively adjusted positively, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the positive adjustment. When the outlet pressure (P2) is still higher than the set value after being updated to an appropriate value and the outlet pressure (P2) cannot be controlled by adjusting the back pressure plate output (M1), the dehydrator is supplied again. The set value of the amount (F2) is adjusted by a certain amount, and the set value of the inlet pressure (P1) is an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the positive adjustment again. Updated to be
The set value of the dehydrator supply amount (F2) is negatively adjusted quantitatively, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment. When the outlet pressure (P2) is still lower than the set value after being updated to an appropriate value and the outlet pressure (P2) cannot be controlled by adjusting the back pressure plate output (M1), the dehydrator is supplied again. The set value of the amount (F2) is negatively adjusted by a certain amount, and the set value of the inlet pressure (P1) is an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment again. It updates so that it may become, The control method of the dehydration system of Claim 1 characterized by the above-mentioned. A control method of a dehydration system in which a concentrating device is arranged in front of a rotary pressure dehydrator,
The rotary pressure dehydrator has a rotating shaft, an inner spacer, an outer spacer, a deflector, and two metal screens fixed to both side surfaces of the inner spacer, and the inner spacer and the deflector from the stock solution supply port. The object to be processed introduced into the annular filter chamber formed between the outer spacer and the outer spacer is advanced forward by rotating the two screens, and is gradually compressed by applying pressure and filtering. A vertical restrictor whose top end is displaced in the vertical direction is disposed below the cake outlet, and a load cell for measuring the main body load (K) acting on the outer spacer and the like during operation of the rotary pressurizer is disposed. ,
The pressure deviation between the measured value and the set value of the inlet pressure (P1) of the rotary pressurization dehydrator is detected, and the inlet pressure (P1) for adjusting the filter rotational speed (R) to the optimum value based on the result is detected. The main body load that detects the load deviation between the control value and the measured value and set value of the main body load (K) of the rotary pressurizer and adjusts the restrictor output (M2) to the optimum value based on the result. The load (K) is continuously controlled,
When the measured value of the main body load (K) is higher than the set value when the restrictor output (M2) is minimum, the set value of the dehydrator supply amount (F2) is quantitatively adjusted positively. The setting value of the inlet pressure (P1) is updated so as to be an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the positive adjustment, and the setting of the updated inlet pressure (P1) is performed. Based on the value, the inlet pressure (P1) is controlled, and the body load (K) is controlled by adjusting the restrictor output (M2).
When the measured value of the main body load (K) is lower than the set value in the state where the restrictor output (M2) is maximum, the set value of the dehydrator supply amount (F2) is quantitatively adjusted to be negative, The setting value of the inlet pressure (P1) is updated so as to become an appropriate value of the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the minus adjustment, and the setting of the inlet pressure (P1) after this update is performed. A control method of a dehydration system, wherein the inlet pressure (P1) is controlled based on the value, and the main body load load (K) is controlled by adjusting the restrictor output (M2). The set value of the dehydrator supply amount (F2) is quantitatively adjusted positively, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the positive adjustment. When the main body load (K) is still higher than the set value after being updated to an appropriate value and the main body load (K) cannot be controlled by adjusting the restrictor output (M2), dehydration is performed again. The set value of the machine supply amount (F2) is adjusted by a certain amount, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the positive adjustment again. Updated to the correct value,
The set value of the dehydrator supply amount (F2) is negatively adjusted quantitatively, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment. When the main body load (K) is still lower than the set value after being updated to an appropriate value and the main body load (K) cannot be controlled by adjusting the restrictor output (M2), dehydration is performed again. The set value of the machine supply amount (F2) is negatively adjusted by a certain amount, and the set value of the inlet pressure (P1) is set to the inlet pressure (P1) corresponding to the dehydrator supply amount (F2) after the negative adjustment again. The dehydrating system control method according to claim 3, wherein the dehydrating system is updated so as to be an appropriate value. A pump is placed between the concentrator and the rotary pressure dehydrator,
When the set value of the dehydrator supply amount (F2) is positively adjusted, in order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the positive adjustment, the concentrator and the rotary pressure dehydrator Adjustment to increase the output (A2) of the pump in between is performed, or adjustment to reduce the opening (B) of the filtrate valve of the concentrator is performed,
When the set value of the dehydrator supply amount (F2) is negatively adjusted, in order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the negative adjustment, the concentrator and the rotary pressure dehydrator The adjustment to reduce the output (A2) of the pump in between is performed, or the adjustment to increase the opening degree (B) of the filtrate valve of the concentrating device is performed. A control method of the dehydration system described in 1. When the set value of the dehydrator supply amount (F2) is positively adjusted, the concentrator supply amount (F1) is increased in order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the positive adjustment. Adjustments are made,
When the set value of the dehydrator supply amount (F2) is negatively adjusted, the concentrator supply amount (F1) is decreased in order to make the actual value of the dehydrator supply amount (F2) coincide with the set value after the negative adjustment. The method for controlling a dehydration system according to claim 1, wherein adjustment is performed.   A densitometer is installed between the concentrator and the rotary pressure dehydrator, and this densitometer is placed under monitoring by the control means, and the concentrator supply amount (F1) is adjusted while observing changes in the measured value of the densitometer. The sludge density | concentration in concentrated sludge is raised or reduced by this, The control method of the dehydration system in any one of Claims 1-5 characterized by the above-mentioned.   The turbidity of the filtrate discharged from the filtrate valve of the concentrator is monitored, and if an abnormality in the filtrate turbidity is detected, the dehydrator supply amount (F2) is forcibly increased by a certain amount, and / or The method for controlling a dehydration system according to any one of claims 1 to 7, wherein an alarm is issued.   Monitors the turbidity of the filtrate discharged from the rotary pressure dehydrator, and if an abnormality in the filtrate turbidity is detected, the dehydrator supply amount (F2) is forcibly decreased by a certain amount and the back pressure plate output The method for controlling a dehydration system according to any one of claims 1 to 8, wherein an adjustment is made to decrease (M1) or the restrictor output (M2) by a certain amount and / or an alarm is issued. .

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