JP5587571B2 - Operation method of dry dehumidifier - Google Patents

Description

  The present invention relates to a method for operating a dry dehumidifier having an adsorption rotor.

  Several proposals have been made to improve the operating efficiency of a dry dehumidifier using an adsorption rotor. An energy-saving method that focuses on changes in the regeneration air volume, regeneration temperature, purge air volume, and rotor speed. As for, the following may be mentioned.

  First, there is an apparatus that measures the regeneration outlet temperature, controls the regeneration air volume so that the regeneration outlet temperature is constant, and controls the purge air volume so that the purge outlet temperature is constant (Patent Document 1). In this method, when the regeneration outlet temperature reaches a certain value, it is determined that regeneration is completed, and the regeneration air volume is controlled so that the regeneration completion state is always maintained.

  This will be described in more detail. FIG. 12 shows a rotor in which an air passage area located on the end face side along the rotation direction of the rotor 101 is divided into a dehumidification area 101a, a regeneration area 101b, and a purge area 101c. 101 shows the outlet air temperature distribution of the regeneration zone 101b and the purge zone 101c. The heat of the regeneration air is first used to increase the temperature of the rotor (a to d in the figure), and then the adsorbed moisture is desorbed. Used as heat (de in the figure). And the characteristic that temperature rises further with completion | finish of a water | moisture-content desorption (ef in a figure) is shown. In view of such characteristics, when controlling the regeneration air volume based on the regeneration temperature, conventionally, as shown in FIG. 13, for example, the coordinate θ (= position angle θ) in the rotation direction of the rotor 101 in the regeneration zone 101b is 50 °. A temperature sensor 102 is installed around the position, and the regeneration air volume is controlled so that the temperature at this position is constant.

  In addition, there has also been proposed one that detects the regeneration outlet air temperature and controls the capacity of a heater that heats the regeneration air so that the regeneration outlet air temperature becomes constant (Patent Document 2). This is intended to achieve an energy saving effect by lowering the regeneration air temperature.

JP-A-11-523 JP 2003-24737 A

  The prior art described in Patent Document 1 has been made on the basis of the knowledge that the dehumidifying ability does not change even if the air volume in the regeneration area with respect to the dehumidifying area is set to 0.2 times to less than 0.4 times. Based on this, it is possible to operate by setting the air volume in the regeneration zone to 0.2 times to less than 0.4 times, and as a result, a more compact system is sufficient, and the energy required for regeneration and purge, fans, multistage By reducing the energy required for processing in the first-stage dehumidifying device when connected to, a large energy saving effect as a whole can be obtained. However, due to the nature of the invention, it could not be used in a region where the ratio of the regenerated air volume to the treated air volume is less than 0.2 times.

  On the other hand, in the prior art described in Patent Document 2, since the dehumidification outlet air dew point is affected by the temperature and relative humidity of the regeneration air, the regeneration air temperature cannot be lowered in order to maintain the treatment outlet air dew point. There is. In particular, when the treatment outlet air dew point is a low dew point, there is a problem that it is difficult to lower the regeneration temperature and the energy saving effect is lowered.

  The present invention has been made in view of the above points, and is independent of the ratio of the regeneration air volume to the treatment air volume, and moreover, is less affected by the dew point at the dehumidification treatment outlet than in the prior art to control the regeneration air volume to dry and dry. The object is to improve the operating efficiency of the dehumidifier.

  According to the inventors' knowledge, it has been found that the regeneration efficiency of the rotor is poor in the winter when the humidity is lower than in the summer, and so far the aim is to improve the regeneration efficiency by changing the amount of regeneration air according to the load. Have been conducting experiments. As a result of such an experiment, it was found that when the regeneration air volume is lowered, the purge air is heated by the heat accumulation of the rotor in the purge area and the rotor is regenerated even if the regeneration is not completely completed in the regeneration area. . That is, it has been found that regeneration is possible while cooling the rotor even in the purge zone.

The present invention has been made by such inventors' research, and is a device for dehumidifying the processing air by passing the processing air through a rotatable rotor, and is located on the end face side of the rotor. The air passing area is divided into a dehumidifying area, a regeneration area, and a purge area, and each of these areas is arranged so that the purge area is located before the transition from the regeneration area to the dehumidifying area by the rotation of the rotor. In the dry dehumidifier, the purge zone is divided into two at the center in the circumferential direction, and the temperature at the highest outlet temperature among the points located on the regeneration zone side is determined from the boundary between the regeneration zone and the purge zone, Among the points located on the regeneration zone side in the range of 0 ° to 10 ° in the position angle θ , the outlet temperature is higher than the outlet temperature at the lowest point and is equal to or higher than the regeneration completion temperature. Regeneration to be introduced into the regeneration area And it is characterized in controlling the amount.

  In this type of dry dehumidifier equipped with a rotor having a dehumidifying zone, a regeneration zone, and a purge zone, the outlet temperature of the regeneration zone and the purge zone during the regeneration of the rotor is a temperature as shown in FIG. The rotor that has changed and has just moved to the regeneration zone through the dehumidification zone is adsorbing more moisture on the exit side of the regeneration zone (= the entrance side of the dehumidification zone) The inlet side (= the outlet side of the dehumidifying zone) is in an unadsorbed dry state. In the first stage of regeneration, first, the temperature of the rotor in the dry region where moisture is not adsorbed on the inlet side is increased by the high-temperature, low-humidity regeneration air. At this stage, the air temperature at the outlet remains almost 12 ° C. (ab in the figure).

  Then, at a stage where the regeneration zone has moved slightly to the purge zone side, the high-temperature / low-humidity regeneration air that has flowed into the area where moisture is adsorbed moves through the rotor on the outlet side while heating the rotor and desorbing moisture. At this time, the temperature of the regenerated air decreases due to desorption heat (heat absorption when moisture is desorbed), and the relative humidity increases, resulting in a low-temperature, high-humidity air condition that cannot contribute to desorption (regeneration). Air and rotor are in an adsorption / desorption equilibrium / thermal equilibrium state). The air temperature in this equilibrium state is about 60 ° C. in the example of FIG. Until the desorption of the entire rotor area is nearing completion, the equilibrium state is maintained near the outlet of the regeneration zone, and the outlet temperature remains constant for a while. When the desorption is completed, the temperature of the outlet air rises from 60 ° C. to 140 ° C. (f in FIG. 12).

  In the present invention, the steps from a to e are the same as in the conventional operation. However, according to the present invention, the rotor is moved to the purge zone in the state of e to f immediately before the completion of desorption by controlling and restricting the regeneration air volume. However, as described above, even if regeneration is not completely completed in the regeneration zone, the purge air is heated by the accumulated heat of the rotor in the purge zone to regenerate the rotor, and the rotor is also cooled in the purge zone. However, since it has been found that regeneration is possible, regeneration of the rotor is possible even when the point where the temperature of the outlet air rises from 60 ° C. to 140 ° C., for example, is in the purge zone.

More specifically, the rotor in the state e in FIG. 12 reaches, for example, 140 ° C. at which most of the region except the vicinity of the outlet can be determined as the regeneration completion temperature. Further, since the heat capacity per volume of the rotor is much larger than the heat capacity of air, the rotor in the state e is in a high temperature heat storage state. When low-temperature purge air is allowed to flow through this rotor, the purge air quickly rises to 140 ° C, and moisture is adsorbed by the high-temperature, low-humidity purge air for a while due to the heat storage effect of the rotor. The temperature is raised and desorbed as it continues to be fed into the area. The present invention utilizes such a phenomenon, and completes the temperature rise and desorption in the purge zone by utilizing the amount of heat stored in the rotor exiting the regeneration zone.

Therefore, according to the present invention, the purge zone is divided into two at the center in the circumferential direction, and the temperature at the highest outlet temperature among the points located on the regeneration zone side is determined from the boundary between the regeneration zone and the purge zone. Among the points located on the regeneration zone side in the range of 0 ° to 10 ° in the position angle θ , the exit temperature is higher than the exit temperature at the lowest point and is equal to or higher than the regeneration completion temperature. In addition, since the amount of regenerative air introduced into the regeneration zone is controlled, it is possible to obtain the dew point temperature of air necessary for proper regeneration and dehumidification processing even if the amount of regenerative air is reduced.

  According to the present invention, since the regeneration air volume is controlled by detecting the outlet temperature in the purge zone when the regeneration is completed, the ratio of the regeneration air volume to the processing air volume does not need to be particularly limited. It can be implemented even in a region where the ratio to the processing air volume is less than 0.2 times. In addition, since the regenerative air volume is the target of control rather than the regenerative heater, the controllable range is wider than the conventional technology that controls the regenerative heater (that is, it is possible to cope with a lower dew point), and the operation is more efficient than conventional Can maintain energy saving effect. Moreover, since the saturated vapor pressure of the regenerative air is higher when the regeneration air volume is reduced and the regeneration temperature is kept higher than when the regeneration air volume is kept constant and the regeneration temperature is lowered, the regeneration vapor is higher in saturation air pressure. As described above, the present invention is more efficient in regeneration than the method of controlling the capacity of the heater for heating the regeneration air. Further, the energy consumed by the regeneration fan can also be saved from Patent Document 2.

  The regeneration completion temperature referred to in the present invention refers to a temperature at which regeneration can be determined to be completed, and differs depending on the moisture absorbent material accommodated in the rotor. In the case of a hygroscopic material used and its configuration, for example, a honeycomb-shaped rotor impregnated with an absorbing liquid such as lithium chloride or calcium chloride, or a rotor composed of an adsorbent such as silica gel or zeolite, the temperature is 60 ° C. to 160 ° C. Yes (in the case of a so-called low temperature regenerative type zeolite rotor that has been recently marketed, it can be judged that regeneration is completed at about 60 ° C.).

  In the present invention, in controlling the regenerative air volume, it can be proposed to control either the regenerative fan or the damper, or both.

When carrying out the present invention, for example, a temperature sensor is installed at a predetermined position angle in the purge area , so that the purge area is divided into two in the center in the circumferential direction, and among the points located on the regeneration area side, The temperature at the point where the outlet temperature is highest is the point where the outlet temperature is the lowest among the points located on the regeneration zone side in the range from 0 ° to 10 ° at the position angle θ from the boundary between the regeneration zone and the purge zone . This can be done by controlling the regenerative air volume while observing the measurement results from each temperature sensor so that the temperature is higher than the outlet temperature at the point and equal to or higher than the regeneration completion temperature, but regeneration is complete after moving to the purge zone. If the temperature increasing point and the temperature rising tendency until the achievement and the temperature decreasing tendency thereafter are examined in advance, the temperature measuring point is set at the stage before the regeneration completion temperature is reached, and the temperature at the measuring point is Playback complete Predetermined temperature lower than the temperature (for example when regeneration completion temperature of 140 ° C., for example 100 ° C.) may be control playback air volume so that. That is, the purge area may be divided into two at the center in the circumferential direction, and the regeneration air volume may be controlled so that the outlet temperature at the point located on the regeneration area side becomes a predetermined temperature set in advance. In such a case, it is desirable to install the measurement point in the vicinity of the rotor outlet as much as possible because the measurement point is easily affected by air other than the measurement point when separated from the rotor outlet. In addition, it has been experimentally confirmed that even if the outlet air temperature in the purge zone is controlled to be constant, the humidity reduction performance does not decrease.

  When actually controlling the regenerative air volume, for example, PID control is generally performed. However, if the dehumidifying load suddenly increases when the control is performed, the regenerative air volume is insufficient if the control response is poor. As a result, there is a risk that the supply air dew point temperature increases. When the dehumidification load fluctuates abruptly, the supply air volume may be varied according to the personnel load in the dry room.For example, when the work load starts decreasing at night or on holidays, If the air pressure increases rapidly, it is possible that the supply air volume increases at a stretch and the dehumidification load changes suddenly. On the other hand, if the responsiveness of the control operation is increased to avoid this, the regenerative air volume hunts and the control stability decreases.

  According to the inventor's knowledge, the control parameter is changed depending on whether the current regeneration air volume is (1) too small, (2) near the target air volume, or (3) excessive. Thus, control response and stability can be secured at the same time. In other words, if the current regeneration air volume is close to the target air volume, slow control with an emphasis on stability will be performed, and if the other regeneration air volume is excessive or insufficient, quick control with an emphasis on responsiveness may be performed. Good.

For this reason, in controlling the regeneration air volume as described above, the first temperature information from the first temperature sensor that detects the temperature at a point closer to the regeneration area than the point in the purge area, and the regeneration Using the second temperature information from the second temperature sensor for detecting the temperature of the point on the regeneration zone side in the range from 0 ° to 10 ° at the position angle θ from the boundary between the zone and the purge zone ,
(1) When the first temperature information <α, the regeneration air volume is increased relatively quickly,
(2) When α <first temperature information and second temperature information <β, the regeneration air volume is increased relatively slowly or decreased relatively slowly,
(3) When β <second temperature information, the actual control may be performed so as to decrease the regeneration air volume relatively quickly. However, α is a temperature lower by about 10 ° C. to 30 ° C. than the predetermined temperature, and β is the predetermined temperature.

  According to the above control method, when α <first temperature information and second temperature information <β, it is determined that the current regeneration air volume is close to the target air volume, and the slow control is performed. When the temperature information <α, the regeneration air volume is quickly increased because the regeneration air volume is too small. When β <second temperature information, the regeneration air volume is quickly decreased because the regeneration air volume is excessive. Responsiveness and stability can be ensured simultaneously.

  For example, when the reproduction air volume is controlled by PID control, individual PID parameters are set and controlled in each of the cases (1) to (3) described above.

By the way, in the prior art, the purge air volume changes in conjunction with the increase / decrease of the regeneration air volume. However, when the purge air volume decreases, the cooling becomes insufficient and the initial stage of the dehumidifying area (the point near the purge area in the dehumidifying area , that is, the dehumidifying area is divided into two in the circumferential direction and located on the purge area side). As a result, the rotor temperature at the point ) rises, and as a result, there is a risk that stable dew point air cannot be supplied. On the other hand, when the purge air volume is increased, the cooling is sufficiently performed but the control temperature becomes unstable. In view of such a situation, based on the outlet temperature at a point closer to the regeneration area than the point in the purge area as described above , that is, a point located on the regeneration area side by dividing the purge area into two in the circumferential direction. In addition to controlling the regeneration air volume, the purge air volume passing through the purge zone may be controlled to be a predetermined value. As a result, the temperature of the control point can be controlled stably.

  However, when the processing air volume to be dehumidified is changed, it is preferable to change the predetermined values of the rotational speed of the rotor and the purge air volume in proportion to the change. That is, when the rotational speed of the rotor is reduced to, for example, half of the rating along with the change in the processing air volume, the predetermined value of the purge air volume is also set to half. In the present invention, since the regeneration air volume is controlled by the outlet temperature of the purge zone, the temperature distribution at the purge zone outlet must be kept constant even when the rotational speed is changed. For this purpose, the total purge air volume (purge time × purge air volume) needs to be constant, and it is preferable to make the rotor rotational speed and the purge air volume proportional. By changing in proportion to this, the temperature distribution in the purge zone does not change. Therefore, even if the rotation speed and the purge air volume are changed, there is no influence on the regeneration air volume control that makes the outlet temperature of the purge area constant. .

  Such a method is effective for reducing the supply air volume when the human body load is low at night or on holidays, for example, in a system that supplies air after dehumidification treatment to a dry room that operates for 24 hours. Driving is possible. According to the inventors, for example, when the dehumidification treatment air volume is reduced to half of the rated value, when only the regeneration air volume is changed and when the regeneration air volume, the rotation speed, and the purge air volume are changed, It is estimated that the amount of heat can be reduced by 25%.

Furthermore, in the configuration in which a part of the processing air volume is used as the purge air volume, the purge air volume can be reduced, and therefore the ratio of the supply air volume per processing air volume can be increased. More specifically, for example, in the case of the system configuration shown in FIG.
(1) When the supply air volume is half of the rating (2) Compared with the case where the supply air volume is half of the rating and the rotation speed and purge air volume are also half of the rating, the supply air volume is halved and the purge air volume is changed In the case of not (1), the ratio of (supply air volume / process air volume) is 0.82. On the other hand, in the case of (2) in which not only the supply air volume but also the rotation speed and purge air volume are halved, the ratio of (supply air volume / process air volume) is 0.9 as in the rated operation.
Thus, in order to supply the same air volume to the target object, the process air volume can be reduced by reducing the rotational speed and the purge air volume. It is clear that when the same air volume is supplied, the smaller the processing air volume, the more energy is saved (reduction in conveyance power and reduction in the amount of regenerated heat).

In controlling the amount of purge air passing through the purge zone to be a predetermined value, the dry dehumidifier is configured so that a part of the air after the dehumidification treatment that has passed through the dehumidification zone is introduced into the purge zone. When the air that has passed through the regeneration zone is mixed with the air that has passed through the regeneration zone and part of it is heated by a heater and introduced into the regeneration zone, it is necessary to ensure that the differential pressure at the inlet and outlet of the purge zone is constant. What is necessary is just to control. Alternatively, necessary control is performed so that the outlet temperature at the point near the dehumidifying area in the purge area , that is, at the point located on the dehumidifying area side by dividing the purge area into two in the circumferential direction becomes the preset target temperature. You may make it perform. The control method differs depending on the specific method of controlling the regeneration air volume based on the outlet temperature near the regeneration zone in the purge zone , that is, the outlet temperature at the point located on the regeneration zone side by dividing the purge zone into two in the circumferential direction. This will be described in an embodiment described later.

  The outlet dew point temperature of the dehumidified air is related to the relative humidity of the regeneration air, and when it is regenerated with air having a low relative humidity, air with a lower dew point can be obtained. Therefore, if the regeneration temperature is the same, the relative humidity of the regeneration air is low in winter or the like when the load is very low, and the air may have a dew point lower than the design standard. Even in the present invention, even when the regeneration air volume is reduced, it is conceivable that the treatment outlet air has a dew point lower than the design value because the relative humidity of the regeneration air is low when the load is extremely low. Therefore, it is possible to raise the dew point temperature at the dehumidification processing outlet by controlling the regeneration heater to lower the regeneration temperature itself and increasing the relative humidity of the regeneration air, as well as controlling the regeneration air volume.

  From this point of view, regeneration to be introduced into the regeneration area based on the dew point temperature on the outlet side of the dehumidification area, the dew point temperature of the target room to which the dehumidified air is supplied, or the dew point temperature of the return air returned from the target room to the dehumidification area It can be proposed to further control the heater that heats the air.

  By reducing both the regenerative air volume and the regenerative heater capacity at the time of low load, regeneration is performed in order to secure the dew point temperature of the supply air, which is seen in the capacity control of the regenerative heater according to the conventional processing load. It is possible to solve the problem that the output of the heater cannot be sufficiently reduced and the energy saving effect is low.

  According to the present invention, it is possible to improve the operation efficiency of the dry dehumidifier regardless of the ratio of the regeneration air volume to the processing air volume and without being affected by the dew point of the dehumidifying air outlet.

It is explanatory drawing which showed typically the outline of the system | strain of the dry-type dehumidification apparatus for enforcing the operating method concerning embodiment. It is a perspective view of the rotor used for the dry-type dehumidifier of FIG. It is an end view of the axial direction of the rotor used for the dry-type dehumidifier of FIG. It is a graph which shows the exit temperature in each position angle of a regeneration zone and a purge zone when the operation method concerning an embodiment is carried out. It is a graph which shows the exit temperature in each position angle of the regeneration zone and the purge zone when the purge air volume fluctuates. It is an end view of the axial direction of the rotor which further installed the temperature sensor for controlling the amount of purge air. It is a graph which shows the exit temperature in each position angle of the regeneration zone and the purge zone when the regeneration air volume and the purge air volume are controlled simultaneously using the rotor of FIG. It is a graph which shows the heat processing heat quantity of the prior art with respect to the process inlet absolute humidity of the winter season with respect to the summer, and this invention. It is a graph of the calculation result and experiment result which show the supply dew point temperature with respect to the reproduction | regeneration air volume ratio at the time of low load and high load. It is an end view of the axial direction of the rotor when a second temperature sensor is added. It is a graph which shows the exit temperature in each position angle which shows a mode when the reproduction | regeneration air volume is controlled using the rotor of FIG. It is a graph which shows the exit temperature in each position angle of a regeneration zone and a purge zone when the driving | operation method concerning a prior art is implemented. It is an end view of the axial direction of the rotor concerning a prior art.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of a system of a dehumidifying system using a dry dehumidifying device 1 for carrying out the operating method according to the present embodiment, and this system is installed in a low dew point space (not shown). It is configured as a system that supplies low dew point air.

  As shown in FIGS. 2 and 3, the dry dehumidifying device 1 that forms the core of the system has a configuration in which area dividing cassettes 12 and 13 are arranged on both end faces of a rotating rotor 11. The end surface of the rotor 11 is divided into three air passage areas, a dehumidification area 11a, a regeneration area 11b, and a purge area 11c, in the order of the rotation direction of the rotor 11 indicated by the arrows in FIGS. A dehumidifying inlet 12a, a regeneration outlet 12b, and a purge outlet 12c for connecting to a duct or the like are formed on the outer end face of the section dividing cassette 12 corresponding to each section. A dehumidification outlet, a regeneration inlet, and a purge inlet are also formed on the outer end face of the zone division cassette 13 corresponding to the three zones (all not shown). In the rotor 11 of the dry dehumidifier 10, a hygroscopic material such as lithium chloride, silica gel, or zeolite is accommodated.

  The three passing areas, the dehumidifying area 11a, the regeneration area 11b, and the purge area 11c, are each in the form of one of the radially formed sections, that is, substantially fan-shaped, and the central angle θ of each passing area is In this embodiment, the central angle θ1 of the dehumidifying zone 11a is set to 270 °, the central angle θ2 of the regeneration zone 11b is set to 60 °, and the central angle θ3 of the purge zone 11c is set to 30 °.

The processing air to be dehumidified is introduced through the processing duct 22 by the processing fan 21, cooled by, for example, the precooler 23, and then introduced into the dehumidifying area 11 a of the rotor 11. Then, the air that has been dehumidified in the dehumidification zone 11 a and has a low dew point, for example, an absolute humidity of 6.7 × 10 ⁻³ g / kg, is led out from the rotor 11 as supply air through the supply duct 24. Thereafter, for example, after necessary temperature adjustment, the air is supplied to the low dew point space as supply air.

  A portion of the air that has been dehumidified in the dehumidification zone 11a and has a low dew point is introduced into the purge zone 11c through the purge introduction duct 25 branched from the supply duct 24, and the air that has left the purge zone 11c is purged. It is sent to the outlet duct 26. The purge outlet duct 26 is connected to a regeneration exhaust duct 27 through which air after exiting the regeneration zone 11b flows, and the air exiting the purge zone 11c is mixed with the air exiting the regeneration zone 11b.

  The air in the regeneration exhaust duct 27 is exhausted to the outside by the regeneration fan 31. A regeneration introduction duct 32 is connected between the purge outlet duct 26 in the regeneration exhaust duct 27 and the exhaust outlet. Has been. A regeneration heater 33 is provided in the regeneration introduction duct 32, and the air in the regeneration introduction duct 32 heated to, for example, 140 ° C. by the regeneration heater 33 is regenerated air as the regeneration zone 11b of the rotor 11. Supplied to.

  Next, the main damper of this system will be described. First, a supply damper D1 is provided downstream of the branch point of the purge introduction duct 25 in the supply duct 24, and an introduction damper D2 is provided in the purge introduction duct 25. It has been. An exhaust damper D3 is provided on the downstream side of the regeneration fan 31 downstream of the connection point of the regeneration exhaust duct 27 with the regeneration introduction duct 32. The regeneration introduction duct 32 is provided with a regeneration circulation damper D4.

  Next, the control system will be described. As shown in FIGS. 1 to 3, a first temperature sensor 41 for detecting the outlet temperature of the purge air is installed at a position near the regeneration zone 11b in the purge zone 11c. Yes. As shown in FIG. 3, the installation position of the first temperature sensor 41 is a point near the regeneration area 11b in the purge area 11c, more specifically, the boundary between the dehumidification area 11a and the regeneration area 11b. When the angle θ = 0 ° and the position angle θ of the boundary between the purge area 11c and the dehumidifying area 11a = 90 °, the angle θ is set at about 65 °. A purge air outlet temperature signal detected by the first temperature sensor 41 is input to the control unit CU. As shown in FIG. 1, the control unit CU controls the regeneration air volume by controlling the regeneration fan 31 or the regeneration circulation damper D4 based on the outlet temperature of the purge air detected by the first temperature sensor 41. The control of the regeneration fan 31 is inverter control.

  Further, as shown in FIG. 1, the control unit CU controls both the regeneration fan 31 and the regeneration circulation damper D4 based on the outlet temperature of the purge air detected by the first temperature sensor 41, and the purge air volume It is also possible to perform control to keep the value at a predetermined value.

  The differential pressure signal at the inlet / outlet of the purge zone 11c detected by the differential pressure gauge 51 that detects the differential pressure at the inlet / outlet of the purge zone 11c of the rotor 11 is input to the control unit CU as shown in FIG. The control unit CU can control the exhaust damper D3 based on the differential pressure at the inlet / outlet of the purge section 11c.

  As shown in FIG. 1, the air after the dehumidification process upstream of the branch point of the supply duct 24 with the purge introduction duct 25 is detected by the dew point sensor 61, and after the dehumidification process detected by the dew point sensor 61. The dew point temperature of the air is input to the control unit CU. The control unit CU can control the capacity of the regenerative heater 33 based on the dew point temperature of the air after the dehumidification process.

  As shown in FIG. 1, the differential pressure signal at the inlet / outlet of the dehumidifying zone 11a detected by the differential pressure gauge 71 that detects the differential pressure at the inlet / outlet of the dehumidifying zone 11a is, as shown in FIG. Is input. The control unit CU can control the drive unit 72 that rotates the rotor 11 and the purge air volume based on the differential pressure at the inlet / outlet of the dehumidifying zone 11a. For example, when the signal of the differential pressure gauge 71 provided for detecting the processing air volume is halved from 300 Pa to 150 Pa, the rotation speed is reduced by halving the output of the inverter of the drive device 72 that controls the rotation speed of the rotor 11. Lower. At the same time, the setting value of the differential pressure gauge 51 for detecting the purge air amount is changed from 300 Pa to 150 Pa, for example, so that the purge air amount is halved. In order to change the purge air volume at this time, the purge differential pressure is controlled to be constant by the inverter of the regeneration fan 31 and / or the exhaust damper D3.

  The dehumidification system having the dry dehumidifier 1 has the above-described configuration, and an operation example thereof will be described next. FIG. 4 shows the position angle θ (coordinates) in the rotational direction of the rotor 11 of the dry dehumidifier 1 and the outlet temperatures in the regeneration zone 11b and the purge zone 11c.

  In this operation example, the rotor 11 immediately after moving to the regeneration zone 11b through the dehumidification zone 11a first adsorbs more moisture to the exit side of the regeneration zone 11b (= the inlet side of the dehumidification zone 11a). In addition, the inlet side of the regeneration zone 11b (the outlet side of the dehumidifying zone 11a) is in a desorbed and dry state.

  In the initial stage (A to B) of regeneration, first, the temperature of the rotor 11 in the dry region where moisture is not adsorbed on the inlet side is increased by high-temperature, low-humidity regeneration air. At this stage, the outlet air temperature remains at about 12 ° C. and hardly changes.

  In the next stage C to D, the high-temperature / low-humidity regeneration air that has flowed into the area where moisture is adsorbed flows through the rotor 11 to the outlet side while the rotor 11 is heated and desorbed. However, at this time, the temperature of the regeneration air decreases due to heat of desorption (heat absorption when moisture is desorbed), and the relative humidity increases, resulting in a low-temperature / high-humidity air state that cannot contribute to desorption (regeneration air and rotor). 11 is an adsorption / desorption equilibrium / thermal equilibrium state). This equilibrium air temperature is about 60 ° C. in this example. Since the equilibrium state is maintained in the vicinity of the outlet of the regeneration zone 11b until the stage E nearing completion of desorption of the entire area of the rotor 11, a state where the outlet temperature is constant continues for a while. Up to this stage, it is the same as the prior art shown in FIG.

  However, in this operation example, the regeneration is performed based on the outlet temperature of the purge zone 11c detected by the first temperature sensor 41 installed at the position angle θ = 65 ° near the regeneration zone 11b in the purge zone 11c. Since the fan 31 or the regenerative circulation damper D4 is controlled to control the regenerative air volume, for example, when the predetermined temperature to be controlled is 100 ° C., the outlet temperature at the relevant point in the purge zone 11c is 100 ° C. In this way, control for reducing the amount of air to be reproduced is performed.

  As a result, the rotor 11 moves to the purge section 11c in the state of E to F immediately before the completion of desorption. Here, in the rotor 11 in the state E, most of the region except for the vicinity of the outlet reaches about 140 ° C. Further, since the heat capacity per volume of the rotor is much larger than the heat capacity of air, the rotor 11 in the state E is in a high temperature heat storage state. When low temperature purge air is passed through the rotor 11, the purge air is quickly heated to 140 ° C., and due to the heat storage effect of the rotor 11, the high temperature / low humidity purge air absorbs moisture for a while. The temperature is continuously increased and desorbed (F to G). As a result, for example, at the stage immediately before the position angle θ = 70 °, the outlet temperature reaches a peak of about 120 ° C. that can be regarded as the regeneration completion temperature. After that, the outlet temperature in the region (H) near the dehumidifying zone 11a in the purge zone 11c becomes 20 ° C. or lower due to the temperature drop by the low temperature and low humidity purge air.

  Thus, in the present operation example, the regeneration fan 31 or the regeneration circulation damper is based on the outlet temperature of the purge area 11c detected by the first temperature sensor 41 installed in the purge area 11c near the regeneration area 11b. D4 is controlled to control the regeneration air volume so that the outlet temperature immediately before the position angle θ = 70 ° is higher than the temperature at the point closest to the regeneration zone and equal to or higher than the regeneration completion temperature. As a result, the energy required for regeneration can be saved more than in the past. More specifically, in the comparison with the conventional technique shown in FIG. 10, the amount (heat amount) of 140 ° C. at the position angle θ = 40-60 ° in the conventional technique is maintained at 60 ° C. It became possible to save energy by that amount.

  In this operation example, the control point, that is, the installation position of the first temperature sensor 41 is set to the position of the position angle θ = 65 °, the predetermined temperature that is the control target temperature is set to 100 ° C., and the regenerative air volume is set. Although this was controlled, it was investigated beforehand that if it reached 100 ° C. at a position angle θ = 65 ° in advance by driving or the like, it reached 120 ° C. which was the regeneration completion temperature after that. Was set as follows. Therefore, the setting of the control point and the predetermined temperature is not limited to this example.

  By the way, only by controlling the regeneration air volume, the purge air volume also changes as the regeneration air volume increases or decreases. When the purge air volume changes, as shown in FIG. 5, the temperature distribution in the purge zone 11c changes, and the control point temperature changes, so that it may be difficult to control stably. In this case, the purge air volume should be controlled to be constant. That is, the purge air volume may be controlled simultaneously with the regeneration air volume. For this purpose, the regeneration fan 31 may be inverter-controlled or the exhaust damper D3 may be controlled so that the inlet / outlet differential pressure in the purge section 11c is constant.

In order to control the regeneration air volume and the purge air volume simultaneously, the following two types of control can be proposed.
(1) When the regeneration air volume is controlled by the regeneration fan 31 based on the outlet temperature of the purge zone, the opening / closing control of the exhaust damper D3 is performed. For example, the opening degree of the exhaust damper D3 is controlled so that the inlet / outlet differential pressure in the purge section 11c of the rotor 11 is constant at 250 Pa, for example.
(2) When the regeneration air volume is controlled by the regeneration circulation damper D4 based on the outlet temperature in the purge zone, the regeneration fan 31 is inverter-controlled so that the inlet / outlet differential pressure is constant at 250 Pa, for example.
In both cases (1) and (2), the control unit CU controls the regeneration fan 31 and the exhaust damper D3 based on a signal from the differential pressure gauge 51 provided at the inlet / outlet of the purge section 11c. it can.

  Alternatively, as shown in FIGS. 6 and 7, in addition to the first temperature sensor 41 for controlling the regenerative air volume, a point closer to the dehumidifying area 11a and the outlet temperature falls (for example, the position angle θ = 80). A temperature sensor 81 for purging air volume control is installed at a point exceeding (°), and the above controls (1) and (2) are performed so that the temperature sensor 81 has a predetermined temperature (target temperature). You may do it.

  If such control is performed, for example, as shown in FIG. 8, it can be seen that regeneration is possible with the output of the regenerative heater about half that of the prior art. That is, according to the inventors' knowledge, when the absolute humidity at the processing inlet, which is a design specification in winter, is about 37% in summer (absolute humidity in winter: 0.6 g / kg, absolute humidity in summer: 1.6 g / kg) ) When the regeneration air volume control is performed, the heat amount of the regenerative heater can be reduced by about 30% in the summer and about 47% in the winter.

  When the processing air volume itself of the dehumidifying process is changed, it is preferable to change the predetermined number of rotations of the rotor 11 and the purge air volume in proportion to the change. This is because the present invention controls the regeneration air volume based on the outlet temperature of the purge zone 11c, so that the temperature distribution on the outlet side of the purge zone 11c must be kept constant even when the rotational speed of the rotor 11 changes. Because there is. Therefore, for example, when the processing air volume is changed from 10 CMM to 5 CMM, the rotational speed of the rotor 11 is halved from 4 RPH, for example, to 2 RPH, and at the same time, the predetermined value of the purge air volume is set to half (for example, 1 CMM → 0.5 CMM). ). According to the inventors' estimation, when the processing air volume is reduced to half of the rating, only the regeneration air volume is changed, and when the regeneration air volume, the rotation speed, and the purge air volume are simultaneously changed as in the present invention. It is considered that the amount of heat for regeneration can be reduced by 25%. Furthermore, since the purge air volume using a part of the processing air volume can be reduced, the ratio of the supply air volume per processing air volume can be increased. Actually, if the processing air volume changes, the absolute humidity of the processing air may change.Therefore, this is not exactly proportional, but the processing air volume is limited only if the absolute humidity of the processing air is the same. Proportional.

  Proportional control of the rotation of the rotor 11 in accordance with such a change in the processing air volume is controlled by the control unit CU based on the signal from the differential pressure gauge 71 and, at the same time, a predetermined control target for the purge air volume. The above-described controls (1) and (2) are carried out so that the value is changed to the predetermined value after the change. That is, (1) When the regeneration air volume is controlled by the regeneration fan 31 based on the outlet temperature in the purge area, the exhaust damper D3 is controlled to open and close. (2) The regeneration air volume is regenerated based on the outlet temperature in the purge area. When controlling by the circulation damper D4, inverter control of the regeneration fan 31 is executed.

  In the present invention, the amount of regenerated air can be significantly reduced by controlling the amount of regenerated air based on the outlet temperature of the purge zone. However, as described above, the relative humidity of the regenerated air is considerable in low load winter seasons and the like. In some cases, the air may have a dew point lower than the design standard. FIG. 9 shows such a phenomenon. For example, when the load is low, the humidity may be reduced by 10 ° C. lower than the design specification of −60 ° C. compared to the case of high load. In that case, the control unit CU controls the regeneration heater 33 based on the dew point temperature detected by the dew point sensor 61, and lowers the regeneration temperature (for example, as shown in FIG. By reducing the temperature to 120 ° C., it is possible to control the dew point temperature of the air after being dehumidified in the dehumidifying zone 11a, and to realize a dew point temperature of −60 ° C. of the design specification.

  As a result of experiments conducted by the inventors, the fan, damper, and rotor speed were not controlled, but all were operated at a fixed rated value, and the regeneration air volume control and the control to make the purge air volume constant were performed. As a result of comparison with the embodiment of the present invention, it can be seen that according to the embodiment of the present invention, about half the regeneration air volume is sufficient in the summer, and about one third of the regeneration air volume is necessary in the winter, It was confirmed that the energy saving effect of the present invention was high.

  In the example shown in FIG. 1, based on the outlet temperature of the purge zone 11c detected by the first temperature sensor 41 installed at the position angle θ = 65 ° near the regeneration zone 11b in the purge zone 11c, The regeneration air volume is controlled by controlling the regeneration fan 31 or the regeneration circulation damper D4. That is, for example, the regeneration air volume is controlled so that the temperature information detected by the first temperature sensor 41 is 100 ° C. (predetermined temperature).

  In this regard, as described above, there is room for improvement in control responsiveness when the dehumidifying load increases rapidly even if PID control is performed, for example, when actually controlling the regenerative air volume. In order to avoid this, if the responsiveness of the control operation is increased, there is a possibility that the reproduction air volume hunts.

  Therefore, in view of such points, in order to ensure control responsiveness and stability at the same time, for example, as shown by a broken line in FIG. 1, in addition to the first temperature sensor 41, the second temperature sensor 42 is It is installed at a point near the purge zone 11c (for example, the position angle θ = 50 °) in the regeneration zone 11b, and not only the temperature information from the first temperature sensor 41 but also the second temperature from the second temperature sensor 42. You may make it control using information.

More specifically, the second temperature information from the second temperature sensor 42 is output to the control unit CU. However, the control unit CU does not directly set the second temperature information as a control target. The control parameter is changed by judging together with the first temperature information from the first temperature sensor 41. In particular,
(1) When the first temperature information <α (for example, 80 °), the regeneration air volume is considered to be too small, and the regeneration air volume is increased relatively quickly.
(2) When α (for example, 80 °) <first temperature information and second temperature information <100 ° (control target temperature), it is determined that the air volume is close to the target air volume, and the regeneration air volume is increased relatively slowly. Or decrease relatively slowly,
(3) When β <second temperature information, it is considered that the regenerative air volume is excessive and the regenerative air volume is decreased relatively quickly.
A control parameter in the control unit CU, for example, a PID parameter is divided into (1) to (3), and control according to each case is performed (multi-PID operation).

  According to such control, as shown in FIG. 11, the outlet temperature is 60 ° C. in the region (position angle 50 ° to 65 °) between the first temperature sensor 41 and the second temperature sensor 42. When it is determined that there is a second rising portion that rises sharply from the beginning, the regeneration air volume is controlled gently, and there is a second rising portion in a region other than the region (see (1) and (3) above) In the case), the regeneration air volume is adjusted relatively quickly. In FIG. 11, the temperature change indicated by the solid line indicates the change in the outlet temperature by the most preferable control of the regeneration air volume.

Therefore, according to such control, it is possible to improve the stability of the regenerative air volume while maintaining the responsiveness immediately after a sudden load change. In the above example, the value of α is set to 80 ° C., for example. However, of course, the value is not limited to this, and a value lower by 10 ° C. to 30 ° C. than the target temperature of the first temperature sensor 41 (70 in the above example). (Degrees C. to 90.degree. C.) (the inventors have actually verified that if set too low, the dew point temperature of the supply air will increase). Also, the position of the second temperature sensor 42 is set to a position angle of 50 ° in the above example. However, any position may be used as long as it detects the temperature near the purge area 11c in the regeneration area 11b. In the embodiment, that is, when the regeneration zone 11b has a position angle of 0 ° to 60 ° and the purge zone 11c has a position angle of 60 ° to 90 °, a position angle of about 40 ° to 55 ° is preferable. Of course, even if the ratios of the regeneration zone 11b and the purge zone 11c are changed, any position may be used as long as the temperature at the point near the purge zone 11c in the regeneration zone 11b is detected.
Furthermore, the number of second temperature sensors to be added to the regeneration area 11b may be plural, and the PID parameters may be set more finely.

  In addition, the PID control described above is basically feedback control, but is not limited to this, and measures the inlet humidity and the treatment air volume of the dehumidifying zone 11a, and determines the optimum regeneration air volume for the measured dehumidifying load in advance. Feed-forward control may be employed in which the calculation is performed by a control arithmetic device, and the regenerative air volume is controlled before the control point temperature changes according to the calculation result.

  In addition, the PI control operation is performed for a predetermined time, and the operation output is held for the subsequent time. Then, after a while after the hold, the PI control operation may be performed again for a certain time and the same operation may be repeated. By holding the output for a certain period of time in this way, it is possible to suppress sudden opening / closing of the damper, etc., so that it is possible to suppress hunting of the reproduction air volume (sample PI control).

  The present invention is useful for a dry dehumidifier having a so-called rotor, and can also be applied to a dry dehumidifier having a multistage connection of rotors.

DESCRIPTION OF SYMBOLS 1 Dry type dehumidifier 11 Rotor 11a Humidification area 11b Regeneration area 11c Purge area 12, 13 Area division cassette 21 Processing fan 22 Processing duct 23 Precooler 24 Supply duct 25 Purge introduction duct 26 Purge derivation duct 27 Regenerative exhaust duct 27
31 regeneration fan 32 regeneration introduction duct 33 regeneration heater 41 first temperature sensor 42 second temperature sensor 51, 71 differential pressure gauge 61 dew point sensor 72 drive device 81 temperature sensor CU control device D1 supply damper D2 introduction damper D3 exhaust damper D4 regeneration Circulation damper

Claims (8)

An apparatus for dehumidifying the processing air by passing the processing air through a rotatable rotor, wherein the air passing area located on the end face side of the rotor is divided into a dehumidifying area, a regeneration area, and a purge area. In a dry dehumidifying device that is partitioned and arranged so that the purge zone is located before moving from the regeneration zone to the dehumidifying zone by rotation of the rotor,
Divide the purge zone in the middle in the circumferential direction, and the temperature at the point where the outlet temperature is the highest among the points located on the regeneration zone side,
Among the points located on the regeneration zone side in the range from 0 ° to 10 ° in the position angle θ from the boundary between the regeneration zone and the purge zone , the outlet temperature is higher than the outlet temperature at the lowest point, And the operating method of the dry-type dehumidifier characterized by controlling the reproduction | regeneration air volume introduce | transduced into a regeneration area so that it may become more than regeneration completion temperature. 2. The dry reduction according to claim 1, wherein the amount of regeneration air is controlled so that the outlet temperature at a point closer to the regeneration zone than the point at which the outlet temperature is highest in the purge zone becomes a predetermined temperature set in advance. How to operate the wet device. In controlling the regenerative air volume,
First temperature information from a first temperature sensor that detects a temperature at a point closer to the regeneration zone than the point at which the outlet temperature is highest in the purge zone;
Using the second temperature information from the second temperature sensor that detects the temperature of the point on the regeneration zone side in the range from 0 ° to 10 ° at the position angle θ from the boundary between the regeneration zone and the purge zone ,
(1) When the first temperature information <α, the regeneration air volume is increased relatively quickly,
(2) When α <first temperature information and second temperature information <β, the regeneration air volume is increased relatively slowly or decreased relatively slowly,
(3) The operation method of the dry-type dehumidifier according to claim 2, wherein when [beta] <second temperature information, the regenerative air volume is decreased relatively quickly.
However, (alpha) is a temperature 10-30 degreeC lower than the said predetermined temperature, (beta) is the said predetermined temperature. The method of operating a dry dehumidifier according to any one of claims 1 to 3, wherein the amount of purge air passing through the purge zone is controlled to be a predetermined value. 5. The method of operating a dry dehumidifier according to claim 4, wherein when the dehumidification treatment air volume is changed, the predetermined values of the rotational speed of the rotor and the purge air volume are changed in proportion to the change. . Part of the dehumidified air that has passed through the dehumidification zone is introduced into the purge zone, the air that has passed through the purge zone is mixed with the air that has passed through the regeneration zone, and a portion of the air is heated with a heater for regeneration. When introducing into the area,
6. The method of operating a dry dehumidifier according to claim 4, wherein the purge air volume is controlled so that the differential pressure at the inlet / outlet of the purge zone is constant, and the exhaust damper or the regeneration fan is controlled. . Part of the dehumidified air that has passed through the dehumidification zone is introduced into the purge zone, the air that has passed through the purge zone is mixed with the air that has passed through the regeneration zone, and a portion of the air is heated with a heater for regeneration. When introducing into the area,
The purge area is divided into two at the center in the circumferential direction, and the purge air volume is controlled so that the outlet temperature at the point located on the dehumidification area side becomes a preset target temperature, and the exhaust damper or the regeneration fan is controlled. The operating method of the dry-type dehumidifier according to claim 4 or 5. Heating the regeneration air to be introduced into the regeneration zone based on the dew point temperature on the outlet side of the dehumidification zone, the dew point temperature of the target room to which the dehumidified air is supplied, or the dew point temperature of the return air returned from the target room to the dehumidification zone The operation method of the dry type dehumidifier according to any one of claims 1 to 7, wherein the heater is controlled.

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