KR20010007322A - Method of dehumidifying compressed gas and apparatus therefor - Google Patents

Abstract

PURPOSE: A method is provided to reduce running costs by a method wherein, in an energy saving operation, adsorbents in one of two absorbing cylinders and those in the other one are caused to be concurrently deteriorated to suppress variation in dew point when a normal operation is restored, whereby replacement operations of adsorbents of both the cylinders are simultaneously carried out. CONSTITUTION: In a method for dehumidifying compressed air, a drying process wherein gas is adsorbed and dried in one of two adsorbing cylinders(3,4) each charged with adsorbents, and a regenerating process wherein a part of the obtained dried gas is led to the other adsorbing cylinder to eliminate the moisture from the adsorbents to purge it are parallelly performed, and these processes are alternately performed by switching both the cylinders to each other to continuously supply dry gas. Under predetermined conditions, for example, if the relationship between the dew point (dew point under pressure) Ta and a set dew point (dew point under pressure) Ts is Ta =< Ts in dried gas, the drying process is continued alternately between both the cylinders, while a process wherein purging of eliminated moisture from each of the cylinders is suspended is provided.

Description

Dehumidification method of compressor body and apparatus therefor {METHOD OF DEHUMIDIFYING COMPRESSED GAS AND APPARATUS THEREFOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dehumidifying a compressor body and an apparatus for adsorption dehumidification and drying of a wet compressor body using an adsorbent, and more particularly, to an energy saving operation for preventing premature deterioration of the adsorbent.

In the conventional dehumidification apparatus, since dry air is continuously supplied, two adsorption cylinders filled with a container containing an adsorbent such as activated alumina, silica gel, synthetic zeolite or lithium chloride are prepared.

Wet compressed air is introduced into one adsorption cylinder, adsorption drying is performed, and it supplies to a predetermined supply source. At the same time, a part of the obtained dry air is introduced into the other adsorption vessel, and the moisture is desorbed from the previous stage to desorb the moisture from the adsorbent whose adsorption capacity is lowered, and regeneration is carried out to purge the moisture from the adsorption vessel. . In this regeneration process, about 20% of the obtained dry air is released to the atmosphere.

The drying of the compressed air in one of the adsorption vessels and the regeneration of the adsorbent in the other adsorption vessel are performed in parallel at the same time, and the switching valves provided between the two adsorption cylinders are switched after a predetermined time has elapsed. Continuously supply dry air.

However, the dehumidifier is designed on the basis of the harshest summer conditions in which the ambient temperature and the inlet air temperature rise, so as to reduce the adsorption of the adsorbent, for example, when the winter system is used or when the load of the supply source is reduced. It is desirable to extend the life.

Conventionally, energy saving operation as shown in FIG. 11 is performed. That is, the switching operation of the switching valve is stopped, and any one of the purge valves connected to the respective suction cylinders is closed. For example, drying is carried out by adsorbing and dehumidifying only by introducing humid compressed air into only B cylinder, and regeneration is stopped in both A and B cylinders.

During the energy saving operation, when the switching operation of the switching valve is stopped and any one of the purge valves connected to the suction cylinder is closed, the amount of dry air discharged by the purge is reduced. However, depending on the conditions, the above-described energy saving operation may be continued for a long time. At this time, an adsorption action is performed only with the adsorbent in one adsorption cylinder, and no adsorbent in the other adsorption cylinder is performed.

Therefore, in the state returned to normal operation, the balance between the water adsorption amount of the adsorbent in the adsorption cylinder which continued the dehumidification drying, and the water adsorption amount of the adsorbent in the other adsorption vessel in which no action is performed deteriorates. . In fact, the dew point temperature of the dry air discharged from the side which continues the dehumidification drying becomes higher than the dew point temperature of the dry air discharged from the other side.

As a result, the adsorbent on which the adsorption action is continued for a long time deteriorates early compared to the adsorbent on the other side, and it is necessary to exchange it with a new adsorbent. When either adsorbent deteriorates, both of them are generally exchanged. On the other side, the adsorbents are unnecessarily exchanged, which adversely affects the operation cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object thereof is to reduce the amount of dry air discharged by purge in a small amount during the so-called energy-saving operation, while advancing deterioration of the adsorbents in both adsorbent cylinders. The dehumidification method of the compressor body and apparatus for suppressing fluctuations in dew point temperature between the adsorbent cylinders when returning to the standard operation, taking out the adsorbent exchange timing at the same time, eliminating unnecessary exchange, and contributing to the reduction of the operation cost. To provide.

1 is an external perspective view of a dehumidifying apparatus according to an embodiment of the present invention;

2 is a schematic cross-sectional view of the dehumidifying apparatus showing the embodiment;

3 is a schematic cross-sectional view of the dehumidifying apparatus showing the embodiment, illustrating a process different from that of FIG. 2;

4 is a view for explaining the dehumidifying action a to d shown in the same embodiment in the order from the switching of the flow path configuration;

5 is a flowchart from switching from standard operation to energy saving operation showing the embodiment;

6 is a view for explaining control in standard operation of the embodiment;

7 is a view for explaining a first control example at the time of energy saving operation at the time of low flow which shows the same embodiment;

8 is a view for explaining the control at the time of energy saving operation at the time of heavy flow which shows the same embodiment;

9 is a view for explaining a second control example at the time of energy saving operation at the time of low flow which shows the same embodiment;

Fig. 10 is a view for explaining a third control example for energy saving operation at the time of low water flow in which a and b are the same embodiment;

Fig. 11 is a diagram for explaining control in the conventional energy saving operation.

♣ Explanation of symbols for main part of drawing ♣

17: Adsorbent 3: adsorption cylinder (A cylinder)

4: suction cylinder (B) 26: switching valve (switching means)

27: Purge means (purge valve) 23: Temperature sensor

25: control circuit (control means) 30: introduction

31: A communication path 32: B communication path

33: Port communication path 34: Fuzzy branch road

MEANS TO SOLVE THE PROBLEM In order to solve the said subject and achieve the objective, the dehumidifying method of the compressor body of this invention, and its apparatus are comprised as follows.

(1) A drying step of adsorbing and dehumidifying by introducing a wet compressor body into one of two adsorption vessels filled with an adsorbent, and a part of the dried body obtained by this drying step in which the hygroscopic ability is lowered in the previous drying step. It is introduced into the adsorption vessel of the side, and the regeneration process which desorbs moisture from an adsorbent and purges desorbed moisture from an adsorption vessel is performed in parallel, and these drying processes are alternately switched between both adsorption vessels, and a dry body is continuously supplied. The dehumidification method is characterized by including a step of stopping purge from each of the adsorption vessels of the dehumidified moisture content, while continuing the drying step alternately between the two adsorption vessels under predetermined conditions.

(2) In the dehumidification method of the compressed air according to (1), the predetermined condition is that the dew point temperature (dew point under pressure) Ta of the dry body obtained in the drying step is set to the dew point temperature (dew point under pressure) (Ts ) Or when deteriorated (Ta≤Ts).

(3) two adsorption vessels filled with an adsorbent, a communication passage and a purge means for communicating these adsorption vessels via a switching means, and a wet compressor body is introduced into one adsorption vessel to adsorb, dehumidify, and dry. A part of this drying body is introduced into the other adsorption vessel, and dehydration is carried out from the adsorber whose adsorption capacity is deteriorated in the previous step, and the regeneration of purging the moisture moisture desorbed by the purge means from the adsorption vessel is performed in parallel. A dehumidifying apparatus for continuously supplying a dry body by alternately switching drying and regeneration between two adsorption cylinders based on a switching, wherein under a predetermined condition, switching of the switching means is continued to alternately wet the compressor body between the two adsorption cylinders. While continuing the dehumidification drying, characterized in that it comprises a control means for controlling to stop the purge means for each adsorption cylinder.

By adopting the means as shown in (1) to (3), the so-called energy saving operation is started under predetermined conditions. At this time, while the purge amount is controlled in small amounts, the deterioration of both adsorbents in the cylinders is equally advanced, and the standard operation is performed. It is possible to suppress fluctuations in dew point temperature between the respective adsorption cylinders when returning to, and to take the adsorbent exchange timing at the same time.

(4) A drying step of adsorbing and dehumidifying by introducing a compressor body into one of two adsorption vessels filled with an adsorbent, and a part of the dried body obtained by this drying step, the other side of which the moisture absorption capacity is deteriorated in the previous drying step. Is introduced into an adsorption vessel, and a regeneration step of desorbing moisture from the adsorbent and purging the desorbed moisture from the adsorption vessel is carried out in parallel. The dehumidification method is characterized in that the regeneration step is stopped under predetermined conditions, and the regeneration step is performed in a predetermined cycle during this stop.

(5) The method for dehumidifying compressed air according to (4), wherein during the stopping of the regeneration step under the predetermined conditions, the drying step is alternately continued between both adsorption cylinders, or only one adsorption cylinder is continued. It is done.

(6) two adsorption vessels filled with an adsorbent, a communication passage and a purge means for communicating these adsorption vessels via a switching means, and a wet compressor body is introduced into one of the adsorption vessels for adsorption, dehumidification, and drying. A part of the desiccant is introduced into the other adsorption vessel, and dehydration of moisture from the adsorbent with reduced hygroscopic ability in the previous step is performed in parallel with the regeneration of purging the moisture desorbed by the purge means from the adsorption vessel, and the switching of the switching means. In the dehumidifier which alternately switches drying and regeneration between the two adsorption cylinders and supplies a dry body continuously, the energy saving operation is performed while stopping the regeneration process under a predetermined condition. And control means for controlling the regeneration process to be performed at a predetermined cycle during the process.

By employing means as shown in (4) to (6), so-called energy saving operation of stopping the regeneration process under predetermined conditions is carried out, and the purge amount is also performed by forcibly purging both adsorbents in both cylinders in a predetermined cycle. While deterioration of the adsorbent is carried out evenly in a small amount, it is possible to suppress fluctuations in the dew point temperature between the adsorption cylinders when returning to normal operation, and at the same time, the adsorbent exchange timing can be taken.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view showing an appearance of a dehumidifier of a compressor body.

The dehumidifier has a main body 1 on the lower side, an electrical parts box 2 mounted on one side of the main body 1, and two suction cylinders mounted on the other side of the main body 1 ( For convenience of explanation, hereinafter, the left adsorption cylinder of the drawing is referred to as A cylinder, and the right adsorption cylinder of the drawing is referred to as B cylinder) (3, 4) and seated over the upper ends of these A, B cylinders (3, 4). It is comprised over the outlet head 5 and A, B cylinder lower end part which become, and consists of an inlet head not shown here.

The outlet head 5 is fixed to the main body 1 via a plurality of strut bolts 6 and a nut 7, whereby the A and B cylinders 3 and 4 are held in a fixed state. The inlet head is shielded by a cover plate 8 mounted to the main body 1.

One outlet side of the outlet head 5 is provided with a discharge port 9 for guiding and supplying the air adsorbed and dried in the apparatus to a predetermined supply destination, and one side of the main body 1 guides the introduction of wet compressed air into the apparatus. The inlet 10 for opening is opened.

Moreover, the humidity indicator 11 is provided in the center of the outlet head 5, The member which contacts with the adsorption-dried gas, and discolors in the state in which this gas exceeded predetermined | prescribed relative humidity is accommodated. That is, the humidity indicator 11 detects the degree of deterioration of the adsorbent contained in the A and B cylinders 3 and 4.

In addition, the outlet head 5 is provided with a purge orifice 12 communicating with the upper end portions on the A and B cylinders 3 and 4. On the side opposite to this purge orifice 12, a pair of connecting bodies 13 for connecting a purge valve described later are provided.

2 and 3 schematically show the cross-section of the same adsorption device and are in different states.

The A and B cylinders 3 and 4 are formed of cylindrical bodies having upper and lower end surfaces opened, and the upper opening is inserted into and coupled to the concave portion 5a provided on the lower surface of the outlet head 5, and the lower opening is the inlet head described above. It is inserted into and coupled to the recess 15a provided on the upper surface of the 15.

Then, the porous plates 16 are provided at positions spaced apart from the upper openings and the lower openings of the A and B cylinders 3 and 4, respectively, and the adsorbents 17 are filled between the porous plates 16. do. As the adsorbent 17, activated alumina, silica gel, zeolite, or the like is used.

In the outlet head 5, a valve chamber 19 for receiving check valves 18A and 18B for preventing reverse flow is formed at positions facing the centers of the A and B cylinders 3 and 4, respectively. These check valves 18A and 18B allow gas to flow upward in the cylinders 3 and 4 on the lower side and prevent the flow of gas into the cylinders 3 and 4 from the top.

In addition, the outlet head 5 is provided with a discharge passage 20 communicating with the discharge port 9 and the valve chambers 19. The check valves 18A and 18B are opened to open the valve chamber 19. It is supposed to lead the gas out to the outlet (9). In addition, a branch path 34 communicating with the humidity indicator 11 is provided in this discharge path 20.

A groove is formed in a range in which the A and B cylinders 3 and 4 are inserted and coupled around the valve chamber 19, and the purge orifice described above (shown here as if installed in the outlet head 5) is shown. It consists of a purge chamber 22 in communication with (12). In other words, the purge chambers 22 communicate with each other by the purge orifices 12.

In the discharge path 20, the end opposite to the discharge port 9 is closed, and the humidity sensor 23 penetrates and is mounted. As shown in FIG. 3 only, the control circuit 25 which is a control means is accommodated in the said electrical component box 2, and is electrically connected with the said humidity sensor 23. As shown in FIG. The humidity sensor 23 detects the humidity of the dry air in the discharge path 20 and sends the detection signal to the control circuit 25.

A switching valve 26 serving as a switching means is mounted on the lower surface of the inlet head 15. The introduction port 10 is provided at one side of the inlet head 15, and the purge valve 27 and the silencer 28 are connected in series to the other side.

The switching valve 26 is provided with the first port (a), the second port (b), the third port (c), the fourth port (d), and the fifth port (e) sequentially from the left side to the right side of the drawing. As the valve body f moves, mutual communication switching of the ports a to e is performed.

That is, in the valve body f position shown in Fig. 2, the first port a and the second port b communicate with each other, and the third port c and the fourth port d communicate with each other. In the valve body f position shown in FIG. 4, the second port b and the third port c communicate with each other, and the fourth port d and the fifth port e communicate with each other.

The valve body f is driven by the solenoid 26S. This solenoid 26S is electrically connected to the control circuit 25, and is to be drive controlled as described later.

The inlet head 15 has an introduction passage 30 for communicating the inlet 10 and the third port c of the switching valve 26, the lower opening end of the A cylinder 3 and the second port b. ), The A communication channel 31 communicating with the A), the lower opening end of the B cylinder 4, and the B communication channel 32 communicating with the fourth port (d), the first port (a) and the fifth A port U-shaped port communication path 33 communicating with the port e and a purge branch path 34 branching from the middle portion of the port communication path 33 to communicate with the purge valve 27 are provided. have.

The purge valve 27 is a solenoid valve of a general configuration and is electrically connected to the control circuit 25. It opens and closes according to the control signal from the control circuit 25, and conducts or cuts off the purge gas introduced from the purge branch path 34. The purge gas derived therefrom is sent to the silencer 28 so as to be discharged to the outside after the noise is reduced.

The control circuit 25 receives a detection signal from the humidity sensor 23 and converts it into a dew point temperature (dew point under pressure) Ta, the dew point temperature Ta and a preset dew point temperature stored in advance. And a circuit for performing switching control of the switching valve 26 and opening / closing control of the purge valve 27 based on the comparison result.

In the adsorption apparatus comprised in this way, the function as demonstrated below is performed. Moreover, it demonstrates by applying compressed air as a compressor body.

When the valve body f of the switching valve 26 is in the position shown in FIG. 2, a drying process is performed in the B cylinder 4, and a boosting process or a regeneration process is performed in the A cylinder 3. As shown in FIG.

That is, the wet compressed air supplied to the dehumidifier is led from the inlet 10 of the inlet head 15 to the third port c of the switching valve 26 via the inlet passage 30, and furthermore, It is guide | induced into the B cylinder 4 from the B cylinder communication path 32 via 4 ports d.

While the wet compressed air passes through the B cylinder 4 from the bottom to the top, a drying step is carried out by adsorption dehumidification and drying by the adsorbent 17 packed therein. Then, the check valve 18A provided in the upper portion is pushed up to be introduced into the discharge path 20 of the outlet head 5, and then discharged and supplied to the predetermined supply destination through the discharge port 9.

In addition, a part of the dry air from the upper opening of the B cylinder 4 is introduced into the purge chamber 22, and the flow rate is further pressurized by the purge orifice 12, and the purge chamber 22 above the A cylinder 3 is opened. Is guided into the A cylinder 3 through the), and passes through the adsorbent 17 filled into the A cylinder 3 to desorb the moisture desorbed from the adsorbent 17 in the previous drying step.

The purge air which is air which desorbed this moisture content is guide | induced from the 1st port a through the 2nd port b from the A-channel communication path 31, and is guide | induced to the port communication path 33. As shown in FIG. From where the fifth port e is closed, purge air is led from the port communication path 33 to the purge branch path 34.

When the purge valve 27 is in the closed state, the purge air is interrupted here, and thus a boosting step is performed in which the pressure in the A cylinder 3 rises. When the purge valve 27 is in an open environment, the purge air passes through the purge valve 27 to reach the silencer 28, where a regeneration process is performed after the noise is reduced and discharged to the outside.

When the valve body f of the switching valve 26 is in the position shown in FIG. 3, a drying process is performed in the A cylinder 3, and a pressure raising process or a regeneration process is performed in the B cylinder 4. As shown in FIG.

That is, the wet compressed air supplied to the dehumidifier is led from the inlet 10 of the inlet head 15 to the third port c of the switching valve 26 via the inlet passage 30. It is guide | induced into A cylinder 3 from A cylinder communication path 31 via two ports b.

While the wet compressed air passes through the inside of the A barrel 3 from the bottom to the top, it is a drying step of adsorption dehumidification and drying by the adsorbent 17 filled therein. Then, the check valve 18A provided on the upper side is pushed up to be guided to the discharge path 20 of the outlet head 5, and then discharged to the predetermined supply destination through the discharge port 9.

In addition, a part of the dry air drawn out from the upper opening of the A cylinder 3 is led to the purge chamber 22, and the flow rate is pressurized by the purge orifice 12 to open the purge chamber 22 above the B cylinder 4. It is guided into the B cylinder 4 through it.

This dry air passes through the adsorbent 17 filled in the B cylinder 4, and desorb | desorbs the moisture which the adsorbent 17 desorbed in the drying process of a previous step. The purge air which is the air which desorbed this moisture content is guide | induced from the B cylinder communication path 32 to the 5th port e via the 4th port d, and is led to the port communication path 33 next.

When the first port a is in the closed state, the purge air is led from the port communication path 33 to the purge branch path 34. When the purge valve 27 is in the closed state, purge air is interrupted here, and a boosting step is performed in which the pressure in the B cylinder 4 rises. When the purge valve 27 is in the open state, the purge air is led to the silencer 28 through the purge valve 27, where a regeneration process is performed to release the noise after the noise is reduced.

Next, as shown in Figs. 4A to 4D, the above-described dehumidification action will be described sequentially from the switching surface of the flow path configuration.

In Fig. 4 (a), the wet compressed air is introduced into the cylinder B (4) through the switching valve (26) and adsorbed and dried by the adsorbent (17) filled therein. The dried compressed air is supplied to the supply source through the check valve 18A.

A part of the dry air from the B cylinder 4 is led to the A cylinder 3 via the purge orifice 12, but the purge valve 27 is closed and the operating pressure inside the A cylinder 3 is maintained. Is stepped up. That is, a drying process is performed in B cylinder 4, and a pressure raising process is performed in A cylinder 3. As shown in FIG.

In Fig. 4B, the switching valve 26 is switched and the purge valve 27 is changed to the open state. The wet compressed air is introduced into the A cylinder 3 through the switching valve 26 and adsorbed and dried by the adsorbent 17.

The dried compressed air is discharged through the check valve 18A. In addition, a part of the dry air from the A cylinder 3 is led to the B cylinder 4 via the purge orifice 12, and the moisture is desorbed by the adsorbent.

This purge air is led to the silencer 28 through the open purge valve 27 and is discharged to the outside. That is, a drying process is performed in the A cylinder 3, and a regeneration process is performed in the B cylinder 4.

In Fig. 4C, the switching valve 26 is kept intact, while the purge valve 27 is closed. Therefore, a drying process is performed continuously in the A cylinder 3, and the pressure raising process which raises a pressure up to an operating pressure in the B cylinder 4 is performed.

In FIG. 4 (d), the switching valve 26 is switched and at the same time, the purge valve 27 is changed to the open state. The wet compressed air is led to the cylinder B (4) via the switching valve (26), and is adsorbed and dried by the adsorbent (17) which has been regenerated.

The dried compressed air is discharged through the check valve 18A. A part of the dry air from the B cylinder 4 is led to the A cylinder 3 through the purge orifice 12, and becomes the purge air from which moisture is desorbed by the adsorbent 17, and the purge valve 27 It is discharged to the outside from the silencer 28 via the. That is, a drying process is performed in the B cylinder 4, and a regeneration process is performed in the A cylinder 3.

After that, it is switched to the state of FIG. 4 (a) again, and the above four steps are sequentially repeated.

In normal operation, control as shown in FIG. 6 is performed.

That is, since the control circuit 25 controls the switching valve 26 to be switched at intervals of 2 minutes, the control circuit 25 includes a drying process of adsorption dehumidification in the A cylinder 3 and a drying process of adsorption dehumidification in the B cylinder 4. The switching of is performed at about 2 minute intervals.

Then, the control circuit 25 performs the opening of the purge valve 27 almost at the same time as the switching of the switching valve 26, and the closing of the purge valve 27 before the next switching of the switching valve 26. To be controlled.

For example, since the drying process of adsorption and dehumidification is performed in the A cylinder 3, when the switching valve 26 is opened several seconds after switching the switching valve 26, when the regeneration purge in the B cylinder 4 starts, Suppresses pressure fluctuations.

The purge valve 27 is set to open only for about 90 seconds, during which the regeneration process in the B cylinder 4 is continued. The purge valve 27 is closed about 90 seconds after the drying step of the A cylinder 3 is started, so that the B cylinder 4 is a step-up process.

The boosting process is continued for about 30 seconds in the B cylinder 4, and after a total of about 120 seconds (2 minutes), the switching valve 26 is switched and the drying process of adsorption dehumidification in the B cylinder 4 is continued for 120 seconds. After a few seconds from this switching, the purge valve 27 is controlled to be opened, and the regeneration process is continued for about 90 seconds on the A cylinder 3 side, and then the purge valve 27 is opened for about 30 seconds to the A cylinder 3 side. To the boosting process.

In the end, the process is continued for about 120 seconds (2 minutes), followed by drying by adsorption dehumidification on the A cylinder 3 side as described above, and regeneration and boosting processes on the B cylinder 4 side, and then repeated in the following order. do.

The humidity sensor 23 detects the humidity of the compressed air dried by adsorption dehumidification and sends a detection signal to the control circuit 25, and calculates the dew point temperature (dew point under pressure) Ta, and calculates the result of the sensor output. Output as voltage.

For example, when the load is small, such as when the amount of air required before supplying from the outlet 9 is extremely small, or when the compressed air introduced from the inlet 10 is extremely low and dried, the energy is reduced. Shift to saving operation.

In practice, switching of the small flow rate to the energy saving operation is performed on the basis of the flowchart as shown in FIG. 5 with respect to the standard operation of the entire flow rate.

That is, the standard operation is started in step S1 from the start. The routine proceeds to step S2, and the humidity sensor 23 detects the humidity of the discharged dry air.

In step S3, upon receiving the detection signal from the humidity sensor 23, the control circuit 25 calculates the dew point temperature (dew point under pressure) Ta. In step S4, the control circuit 25 compares the preset dew point temperature (temperature under pressure) Ts stored in advance with the calculated dew point temperature Ta.

If the calculated dew point temperature Ta is lower than or equal to the set dew point temperature Ts (Ta ≦ Ts), the procedure is Yes, and the flow proceeds to step S5, and the energy saving operation described later is started. When the calculated dew point temperature Ts becomes higher than the set dew point temperature Ts, the calculated dew point temperature Ts becomes No, and the flow returns to the standard operation of step S1.

7 shows a first control example in the energy saving operation.

In the control circuit 25, the preset dew point temperature Ts stored in advance is, for example, a dew point of -40 ° C under pressure, and the calculated dew point temperature Ta is equal to or lower than the set dew point temperature Ts. The start signal for saving operation is output.

The switching valve 26 switches the dehumidification drying of the A cylinder 3 and the dehumidification drying of the B cylinder 4 every two minutes as mentioned above. Then, the purge valve 27 is opened and the regeneration purge of the B cylinder 4 is performed at about the same time as the switching of the dehumidifying drying to the A cylinder 3, and then the purge valve 27 is closed to boost the pressure. . After 2 minutes, the regeneration purge of the A cylinder 3 is performed at approximately the same timing as the switching of the dehumidification drying of the B cylinder 4, and then the pressure is increased.

The dew point temperature drops from -40 ° C to -45 ° C where the load is extremely small or where the humidity of the introduced compressed air is extremely low. Further, the switching control for the switching valve 26 continues at intervals of two minutes, but the purge valve 27 remains closed. As a result, almost equally moist compressed air is introduced into the A cylinder 3 and the B cylinder 4, and the adsorbents 17 in the respective cylinders 3 and 4 perform the same adsorption action. Therefore, the dryness of the detected dry air is kept constant without fluctuation.

The dew point temperature Ta gradually rises again from -45 ° C when there is no purge of the moisture desorbed to the adsorbent 17 by the closing of the purge valve 27. After the switching of the switching valve 26 is performed for a predetermined cycle (for example, 3 cycles: 12 minutes), the purge valve 27 is opened once.

The purge valve 27 is opened only for one cycle of the switching valve 26, for example. That is, the regeneration purge of the B cylinder 4 is performed almost at the same time as the switching of the dehumidification drying of the A cylinder 3, and the regeneration of the A cylinder 3 is performed at almost the timing of the switching of the dehumidification drying of the B cylinder 4. Purge is performed.

Therefore, by repeating the dehumidification drying during the energy saving operation, the moisture content remaining in the A, B square cylinders 3 and 4 is purged, and the adsorption degree of the adsorbent 17 is restored to some extent. Thereafter, the flow returns to the continuation of the switching control of the switching valve 26 as described above and the closing of the purge valve 27 during the predetermined cycle.

By switching to the energy saving operation as described above, the amount of purge is reduced and the energy loss can be reduced. Then, deterioration of the adsorbent 17 is minimized by purging the cylinders 3 and 4 every predetermined cycle.

When the load returns to its original state or when the humidity of the compressed air introduced again rises, the calculated dew point temperature Ta becomes higher than the set dew point temperature Ts, so that the control circuit 25 again returns to the standard of Control to return to operation.

Even when returning to the standard operation, since the dehumidification drying was continued evenly in the A, B cylinders 3 and 4 during the energy saving operation, the dew point fluctuations of the dry air obtained in the dehumidification step with each other are almost nonexistent.

In addition, deterioration of the adsorbent 17 in the A, B square cylinders 3 and 4 proceeds evenly during the energy saving operation, and thus, when it is necessary to replace the A, B square cylinders 3 and 4, The adsorbents 17 may be replaced at the same time.

The above is an explanation of the energy saving operation in which only a small amount of dehumidified and dried compressed air needs to be supplied. However, in the so-called heavy oil flow rate between the energy saving operation of this small flow rate and the standard operation of all flow rates described above. The energy saving operation will be described below.

As shown in FIG. 8, the switching valve 26 is switched every two minutes, and the dehumidification drying process in A, B square cylinders 3, and 4 is continued alternately. On the other hand, it is determined that the calculated dew point temperature Ta is equal to or less than the set dew point temperature Ts and enters the energy saving operation. That is, the purge valve 27 is closed almost at timing with the switching of the dehumidification drying of the A cylinder 3, and the regeneration purge in the B cylinder 4 is stopped.

However, since the load is somewhat high, the dew point temperature Ta becomes higher than the set dew point temperature Ts by stopping the regeneration purge. Thus, the purge valve 27 is opened at approximately the same time as the switching of the dehumidification drying of the B cylinder 4 to perform the regeneration purge of the A cylinder 3.

Then, since the dew point temperature Ta becomes lower than the set dew point temperature Ts, the purge valve 27 is closed by stopping the purge valve 27 at the same time as the dehumidification drying switching of the A cylinder 3 to stop the regeneration purge of the B cylinder.

Hereinafter, the energy saving operation at the heavy flow rate is performed in four cycles of the dehumidification drying switching for the A, B square cylinders 3 and 4 of the switching valve 26, and the dew point temperature Ta is lower than the set dew point temperature Ts. Each time it rises, the purge valve 27 is opened and the regeneration purge in the corresponding square cylinders 3 and 4 is performed. As a result, the dew point fluctuation at the time of returning to the standard operation is suppressed as much as possible.

In addition, although not shown in particular, depending on the conditions, it is possible to rank in the energy saving operation of the small flow rate.

That is, the energy saving operation of the low flow rate described above was to open the purge valve 27 every four cycles of the dehumidification drying switching for the A, B square cylinder (3), (4) of the switching valve 26, but is limited to this It is not.

The dehumidification drying switching of the selector valve 26 is 6 cycles or 8 cycles based on a previously stored set dew point temperature Ts at a lower value, for example, a dew point under pressure -62 ° C or -80 ° C. The purge valve 27 may be opened once every time, and further energy saving operation may be performed.

9 shows a second control example in the energy saving operation. In the same manner as described above, the start signal of the energy saving operation is output.

The switching valve 26 switches the dehumidification drying of the A cylinder 3 and the dehumidification drying of the B cylinder 4 every two minutes as mentioned above. The purge valve 27 is opened and the regeneration purge of the B cylinder 4 is performed at approximately the same time as the switching of the dehumidifying drying to the A cylinder 3, and then the purge valve is closed to increase the pressure. After 2 minutes, the regeneration purge of the A cylinder 3 is performed at approximately the same timing as the switching of the dehumidification drying of the B cylinder 4, and then the pressure is increased.

When the load is extremely small or the humidity of the introduced compressed air is extremely low, the dew point temperature is lowered from -40 ° C to -45 ° C. Further, the switching control for the switching valve 26 continues at intervals of two minutes, but the purge valve 27 remains closed. As a result, the compressed air moistened almost evenly is introduced into the A cylinder 3 and the B cylinder 4, and the adsorbents 17 in the respective cylinders 3 and 4 perform the same adsorption action. Therefore, the dryness of the detected dry air is kept constant without fluctuation.

When there is no purge of the moisture desorbed to the adsorbent 17 by the closing of the purge valve 27, the dew point temperature Ta gradually rises again at -45 ° C. After the switching of the switching valve 26 is performed for a predetermined cycle (for example, 3 cycles: 12 minutes), the purge valve 27 is operated in one cycle of the dehumidification drying switching of the next A, B cylinders 3 and (4). Controlled.

That is, based on the first switching cycle of the switching valve 26, the purge valve 27 is controlled at the fourth cycle. Specifically, the regeneration purge of the B cylinder 4 is performed at about the same time as the switching of the dehumidification drying of the A cylinder 3, and the A cylinder 3 is arranged at approximately the same time as the switching of the dehumidification drying of the B cylinder 4 at the same time. Regeneration purge is performed.

Thereby, the moisture content remaining in A, B square cylinders 3 and 4 is forcibly purged by repetition of dehumidification drying during energy saving operation, and the adsorption degree of the adsorbent 17 is restored to some extent.

Thereafter, the switching control of the switching valve 26 as described above is continued, and the control of the purge valve 27 every four cycles is performed. The pattern described above does not change while the energy saving operation continues.

So-called energy saving operation is performed in which the amount of purge can be reduced to reduce the energy loss. And deterioration of the adsorbent 17 is suppressed to a minimum by performing control purge with respect to the adsorbent 17 in each cylinder 3 and 4 every predetermined cycle.

When the load returns to the original state or when the temperature of the compressed air introduced again rises, the calculated dew point temperature Ta becomes higher than the set dew point temperature Ts, so that the control circuit 25 again returns to Control to return to normal operation.

Even after returning to the standard operation, the dew point fluctuation of the dry air obtained was performed because the regeneration process of forcibly purging desorbed moisture was performed evenly with respect to the adsorbents 17 of the A, B cylinders 3 and 4 during the energy saving operation. There is almost no.

During the energy saving operation, deterioration of the adsorbent 17 in the A, B cylinders 3 and 4 proceeds evenly, and thus, when it is necessary to replace the A, B cylinders 3, 4 The adsorbents of) may be replaced at the same time.

In addition, during the energy saving operation to stop the regeneration process described above, the purge valve 27 is controlled to be opened every four cycles of the dehumidification drying switching to the A, B corner cylinders 3 and 4 of the switching valve 26. It is not limited to this.

10 (a) and 10 (b) show a third example of control in energy saving operation.

As shown in Fig. 10 (a), the purge valve 27 may be opened and controlled every 5 cycles of the dehumidification drying switching, and the number of cycles may be determined based on the dew point of the air after adsorption drying. It can change suitably by various conditions, such as correspondence.

In addition, it is not necessarily limited to alternately performing dehumidification drying switching with respect to A, B square cylinders 3, and 4 of the switching valve 26 during energy saving operation. For example, as shown in FIG. 10 (b), while the purge valve 27 is closed to stop the regeneration process, the switching valve 26 is switched from the A cylinder 3 to the B cylinder 4. The energy saving operation which maintains a state of a state may be sufficient.

However, in this state as well, the purge valve 27 is controlled to be opened in a predetermined cycle to force the purge equally to the adsorbents 17 of the respective cylinders 3 and 4.

According to the invention of Claims 1 to 3, during the so-called energy-saving operation, the dehumidification drying switching is continued in both adsorption cylinders, and the regeneration purge in each cylinder is stopped to reduce the amount of dry air discharged by the purge. While suppressing it to a small amount, the deterioration of adsorbents in both adsorption cylinders is evenly progressed, and the fluctuation of dew point temperature between the adsorption cylinders when returning to normal operation is suppressed, thereby improving the reliability and adsorbents in both adsorption cylinders. At the same time, the timing of the replacement is used to eliminate unnecessary exchange, thereby contributing to the reduction of the running cost.

According to the inventions of claims 4 to 6, during so-called energy-saving operation, the forced purge of the adsorbents in the respective adsorption vessels is carried out in a predetermined cycle, thereby suppressing the amount of dry air discharged by the purge in a small amount. The deterioration of the adsorbents in the cylinders is carried out evenly, the fluctuation of dew point temperature between the adsorption cylinders when returning to the standard operation is improved, thereby improving the reliability, and at the same time performing the adsorbent replacement timing of both adsorption cylinders. The effect of eliminating an unnecessary exchange and contributing to the reduction of the running cost is achieved.

Claims (6)

Adsorption dehumidification by introducing a wet compressor body into one of the two adsorption vessels filled with the adsorbent, and a part of the dried body obtained by this drying process is adsorbed on the other side of which the moisture absorption capacity is deteriorated in the previous drying process. Compressor body which introduces into the cylinder and desorbs moisture from the adsorbent and purges the desorbed moisture from the adsorption cylinder in parallel. In the dehumidification method of, And a step of stopping the purge from the respective adsorption vessels of the dehumidified moisture content, while continuing the drying step alternately between the two adsorption vessels under the predetermined conditions. The method of claim 1, The predetermined condition is characterized in that the dew point temperature (dew point under pressure) Ta of the dry matter obtained in the drying step is equal to or lower than the set dew point temperature (dew point under pressure) Ts, (Ta≤Ts). Dehumidification method of the compressor body. Two adsorption vessels filled with an adsorbent, communication passages and purge means for communicating these adsorption vessels via a switching means, and a wet compressor body is introduced into one adsorption vessel for adsorption, dehumidification, and drying. A part of is introduced into the other adsorption vessel and dehumidifying the moisture from the adsorbent whose adsorption capacity is lowered in the previous stage, and regenerating the purge of the moisture desorbed by the purge means from the adsorption vessel in parallel, based on the switching of the switching means. In the dehumidifying apparatus of the compressor body which alternately switches between drying and regeneration between the two adsorption cylinders and continuously supplies a dry body, And control means for controlling switching of the switching means to continue the dehumidification drying of the wet compressor body alternately between the two suction cylinders under predetermined conditions, and to stop the purge means for each suction cylinder. Dehumidifier of the compressor body. A drying step of adsorbing and dehumidifying by introducing a compressor body into one of two adsorption vessels filled with an adsorbent, and a part of the drying body obtained by this drying step, the other adsorption vessel whose moisture absorption capacity is deteriorated in the previous drying step. A regeneration step of introducing and desorbing moisture from the adsorbent and purging the desorbed moisture from the adsorption vessel, and alternately switching these drying and regeneration processes between the two adsorption vessels to continuously supply the dry matter. In the dehumidification method, A method for dehumidifying a compressor body, characterized in that the regeneration process is stopped under predetermined conditions and the regeneration process is performed in a predetermined cycle during the stop. The method of claim 4, wherein During the energy saving operation, the drying step is alternately continued between the two adsorption cylinders, or only one adsorption cylinder is continued, characterized in that the compressor body dehumidification method. Two adsorption vessels filled with an adsorbent, communication passages and purge means for communicating these adsorption vessels through a switching means, and a wet compressor body is introduced into one adsorption vessel, adsorption, dehumidification, drying, and A part is introduced into the other adsorption vessel, and the moisture is desorbed from the adsorption agent whose hygroscopicity has decreased in the previous stage, and the regeneration of the moisture desorbed by the purge means from the adsorption vessel is performed in parallel, and based on the switching of the switching means. In the dehumidifying apparatus of the compressor body which alternately switches drying and regeneration between both adsorption cylinders and continuously supplies a dry body, And a control means for controlling the energy saving operation to stop the regeneration step under predetermined conditions and controlling the regeneration step to be performed in a predetermined cycle during the energy saving operation.