KR20120040648A - Heat recovery system - Google Patents

Abstract

PURPOSE: System for recovering heat is provided to obtain warm water of wanted temperature, and not to influence to the cooling of compressor in case of controlling the temperature or the amount of warm water. CONSTITUTION: System for recovering heat comprises a first air cooler(8) for cooling compressed air from a compressor, a first oil cooler(10) cooling lubricant of the compressor, a second oil cooler(11), which is installed in oil pipeline(14) of the first cooler, use as heat exchanger heating water by heat of lubricant, and a second air cooler(9), which is installed in air pipeline(12) of the first air cooler, heating water by compressed air transferred to the first air cooler.

Description

Heat recovery system {HEAT RECOVERY SYSTEM}

The present invention relates to a heat recovery system for recovering the heat of compression of the air compressor.

Patent Literature 1 below discloses a heat recovery system that uses water supply to a water supply tank of a boiler to achieve cooling of compressed air or lubricating oil from a compressor and thereby to heat water supply to a water supply tank. Specifically, water is supplied to the water supply tank 7 of the boiler 2 through the air cooler 32 and the oil cooler 31, and the air cooler 32 allows the compressed air to be cooled, while the oil cooler ( At 31, cooling of the lubricating oil of the compressor 5 is attained, and the water supply to the water supply tank 7 is heated in each cooler 31,32.

 By the way, the cooling method of the compressor is water-cooled and air-cooled, but in the case of water-cooled, the air cooler 32 and the oil cooler 31 of the compressor unit 6 usually circulate water between coolant coolers such as a cooling tower, and the air cooler. And water passing through the oil cooler is cooled by the cooling water cooler and reused, but in the invention described in Patent Document 1, it can be said that the hot water is to be manufactured instead of the circulation of such cooling water.

Japanese Patent Publication No. 2010-38385

However, in the invention described in Patent Document 1, only one air cooler and one oil cooler are provided. That is, it is a mechanism which aims at heat recovery using the air cooler and oil cooler which a compressor unit should originally have. And it is a structure which adjusts the quantity which passes to each cooler based on the temperature of the compressed air to an air cooler, or the temperature of the lubricating oil to an oil cooler, to keep the temperature desired.

Therefore, the cooling water is not circulated between the air cooler and the oil cooler in the water-cooled compressor and the coolant cooler such as the cooling tower, and in the air-cooled compressor, the outside air is passed through the air cooler and the oil cooler to cool the compressed air or lubricant. Nor is it. Therefore, it does not leave the existing cooling system originally provided by the compressor.

In addition, it is not possible to adjust the presence or absence of the water supply according to the use load (required amount) of the hot water obtained by passing through each cooler. For example, even if there is little or no use of hot water, even if it is desired to stop the production of hot water, stopping the production of hot water stops the supply of cooling water to each cooler, thereby preventing the cooling of compressed air and lubricating oil. Therefore, it is impossible to produce hot water in accordance with the use load of hot water.

In addition, since the amount of water supplied to each cooler is adjusted to maintain compressed air or lubricating oil at a desired temperature, the presence or absence of water supply to each cooler is not adjusted to maintain the hot water obtained by passing through each cooler at a desired temperature. That is, hot water of a desired temperature cannot be obtained.

The problem to be solved by the present invention is to provide a heat recovery system that can recover the heat of compression while leaving the existing compressor cooling system intact. Further, it is desirable to provide a heat recovery system which can be operated in accordance with the use load of hot water or in order to obtain hot water at a desired temperature.

This invention is made | formed in order to solve the said subject, The invention of Claim 1 has the 1st air cooler which cools the compressed air from a compressor, the 1st oil cooler which cools the lubricating oil of the said compressor, and the said 1st oil cooler. And a second oil cooler serving as a heat recovery heat exchanger for heating water by the heat of the lubricating oil sent to the first oil cooler.

According to the invention of claim 1, a second oil cooler is provided in addition to the first air cooler and the first oil cooler, and the heat of compression can be recovered in the second oil cooler. At this time, the heat of compression can be recovered in the second oil cooler while using the first air cooler and the first oil cooler as the existing compressor cooling system. In addition, even if the presence or the amount of water that is passed through the second oil cooler is adjusted according to the use load of hot water, the first air cooler and the first oil cooler can be configured so as not to affect the predetermined cooling of the compressed air or the lubricating oil. have.

Invention of Claim 2 is provided with the 2nd air cooler in addition to the said 2nd oil cooler of Claim 1, This 2nd air cooler is provided in the air path to the said 1st air cooler, The said 1st air cooler A heat recovery heat exchanger for heating water with heat of compressed air sent to the heat exchanger, wherein the second air cooler and the second oil cooler are arranged to pass water in series or in parallel.

According to the invention of claim 2, in addition to the first air cooler and the first oil cooler, a second air cooler and a second oil cooler are provided, and compressed heat can be recovered in the second air cooler and the second oil cooler. At this time, the heat of compression can be recovered in the second air cooler and the second oil cooler while using the first air cooler and the first oil cooler as the existing compressor cooling system. In addition, adjusting the presence or the amount of water that leads to the second air cooler and the second oil cooler according to the use load of hot water does not affect the predetermined cooling of the compressed air or the lubricating oil in the first air cooler and the first oil cooler. It can be done without the configuration.

Invention of Claim 3 is provided with the 2nd air cooler instead of the said 2nd oil cooler, This 2nd air cooler is installed in the air path to the said 1st air cooler, and it is provided with the said 1st air cooler. It is a heat recovery system for heat recovery which heats water by the heat of compressed air sent.

According to invention of Claim 3, in addition to a 1st air cooler and a 1st oil cooler, it is provided with a 2nd air cooler, and can collect the heat of compression in a 2nd air cooler. At this time, the heat of compression can be recovered in the second air cooler while using the first air cooler and the first oil cooler as the existing compressor cooling system. Further, even if the presence or the amount of water to be passed to the second air cooler is adjusted according to the use load of hot water or the like, the first air cooler and the first oil cooler do not affect the predetermined cooling of the compressed air or the lubricating oil. have.

The invention according to claim 4 controls the presence or absence of water supply to the heat recovery heat exchanger according to any one of claims 1 to 3, based on the use load of hot water after passing through the heat recovery heat exchanger. It is a heat recovery system characterized in that.

According to invention of Claim 4, desired hot water can be manufactured by controlling water supply based on the use load of hot water. Further, even if the water supply is controlled based on the use load of hot water, the first air cooler can reliably cool the compressed air, and the first oil cooler can reliably cool the lubricating oil.

The invention according to claim 5 controls the presence or absence of water supply to the heat recovery heat exchanger according to any one of claims 1 to 3, based on the temperature of the hot water after passing through the heat recovery heat exchanger. It is a heat recovery system characterized by the above-mentioned.

According to invention of Claim 5, desired hot water can be manufactured by controlling water supply based on the temperature of hot water. Moreover, even if water supply is controlled based on the temperature of the hot water, the first air cooler can reliably cool the compressed air, and the first oil cooler can reliably cool the lubricating oil.

The invention according to claim 6 is the oil-lubricated compressor according to any one of claims 1 to 3, wherein the compressor is provided with an oil separator that separates the lubricating oil from the compressed air discharged from the compressor, and the lubricating oil is separated by the oil separator. Compressed air is sent to each said air cooler, and the lubricating oil from the said oil separator is sent to each said oil cooler, It is a heat recovery system characterized by the above-mentioned.

According to the invention described in claim 6, the oil-lubricated compressor can be configured to exhibit the same effects as the invention described in any one of claims 1 to 3.

The invention as set forth in claim 7, wherein the compressor is a non-lubricating compressor having a low stage compressor and a high stage compressor, and compressed air from the low stage compressor is passed through the first inter cooler to the high stage compressor. To the respective air coolers as an after cooler, which are further compressed in the high stage compressor, and are installed in a blower from the low stage compressor to the first inter cooler and sent to the first inter cooler. And a second inter cooler as a heat exchanger for heat recovery for heating water.

According to invention of Claim 7, it can be comprised so that a non-lubricating compressor can exhibit the effect similar to invention of any one of Claims 1-3.

The invention according to claim 8, wherein in the heat recovery heat exchanger, water is heated to generate steam, and the presence or absence of water supply to the heat exchanger for heat recovery is based on the water level of the heat recovery heat exchanger. Or a heat recovery system, characterized in that the amount is controlled.

According to invention of Claim 8, steam can be obtained by recovering the heat of compression of an air compressor.

In the invention according to claim 9, the compressor is a water-lubricated compressor, and instead of the lubricating oil, lubricating water is used, whereby the first oil cooler cools the lubricating water. While being a first water cooler, said second oil cooler becomes a second water cooler as a heat recovery heat exchanger for heating water with heat of lubricating water sent to said first water cooler, and compressed air discharged from said compressor. And a separator for separating the lubricating water from the furnace, and the first air cooler is not installed so that the compressed air from the compressor is discharged through the separator.

According to the invention described in claim 9, the water-lubricated compressor can also be configured to exhibit the same effects as the invention described in any one of claims 1 to 3.

(Effects of the Invention)

According to the present invention, it is possible to realize a heat recovery system capable of recovering compressed heat while leaving the existing compressor cooling system intact. Moreover, according to embodiment, it becomes possible to drive according to the use load of hot water, or to operate so that hot water of desired temperature may be obtained. And even if it adjusts the quantity or temperature of hot water obtained, it can be set as the system which does not affect cooling of a compressor.

1 is a schematic view showing Embodiment 1 of a heat recovery system of the present invention.
2 is a schematic view showing Embodiment 2 of a heat recovery system of the present invention.
3 is a schematic view showing a third embodiment of the heat recovery system of the present invention, and shows only the change points of the first embodiment or the second embodiment.
4 is a schematic view showing Embodiment 4 of a heat recovery system of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the specific Example of this invention is described in detail based on drawing.

Example 1

1 is a schematic view showing Embodiment 1 of a heat recovery system of the present invention.

The heat recovery system 1 of this embodiment is a system for recovering compressed heat of an oil-lubricated (lubricated) or water-cooled electric air compressor. Specifically, indirect heat exchange of the compressed air or lubricating oil from the compressor 2 and the water supply from the water softener 3 to the water supply tank 5 of the boiler 4 is performed to cool the compressed air or lubricating oil and supply the water to the water supply tank 5. It is a system to plan heating.

The heat recovery system 1 of the present embodiment aims to cool the compressor 2 for sucking, compressing and discharging the outside air, the motor 6 for driving it, the oil separator 7 for separating the lubricating oil from the compressed air, and the compressed air. The main part includes the first air cooler 8 and the second air cooler 9, the first oil cooler 10 and the second oil cooler 11 for cooling the lubricating oil.

The compressor 2 is driven by the motor 6 to inhale, compress and discharge the outside air. The compressed air discharged from the compressor (2) is sent to the oil separator (7) to separate and remove the lubricating oil in the oil separator (7).

The compressed air from which the lubricating oil is removed by the oil separator 7 is sent to the compressed air using device (not shown) through the first air cooler 8 in the case of the conventionally known compressor unit, but in the present embodiment, the second air cooler ( 9) and the first air cooler 8 to the compressed air using apparatus. That is, in the present embodiment, the second air cooler 9 is installed in the air passage 12 from the oil separator 7 to the first air cooler 8, and the compressed air from the oil separator 7 is the second air. It is sent through the cooler 9 and the first air cooler 8 to the compressed air using device. Moreover, the dryer 13 is provided in the exit side of the 1st air cooler 8 as desired, and moisture is removed by the dryer 13, and compressed air is sent to a compressed air utilization apparatus.

Meanwhile, the lubricant of the compressor 2 is returned to the compressor 2 through the first oil cooler 10 in the case of the conventionally known compressor unit, but in the present embodiment, the second oil cooler 11 and the first oil cooler 10 are returned. Is returned to the compressor (2). That is, in this embodiment, the second oil cooler 11 is installed in the oil passage 14 from the oil separator 7 to the first oil cooler 10, and the lubricating oil from the oil separator 7 is the second oil cooler. Return to compressor 2 via 11 and first oil cooler 10.

The oil passage 7 from the oil separator 7 to the second oil cooler 11 and the oil passage from the first oil cooler 10 to the compressor 2 are connected in the bypass passage 15. And the temperature control 3-way valve 16 is provided in the oil flow path from the oil separator 7 to the 2nd oil cooler 11, and the branch part of the bypass path 15. As shown in FIG. The temperature regulating three-way valve 16 is preferably a wax type, and the oil cooler 11 or 10 may be supplied to each oil cooler 11 or 10 based on the temperature of the lubricant oil from the oil separator 7. The distribution ratio of whether to return to the compressor 2 through the bypass passage 15 without using is adjusted by magnetic force. Thereby, the flow volume of the lubricating oil which flows into each oil cooler 11 and 10 can be adjusted, and the lubricating oil in the compressor 2 can be maintained at desired temperature.

Hereinafter, each cooler 8-11 is demonstrated in order. Firstly, the first air cooler 8 is an indirect heat exchanger of compressed air and its cooling water. The second air cooler 9 is also an indirect heat exchanger of compressed water and water supply to the water supply tank 5.

On the other hand, the first oil cooler 10 is an indirect heat exchanger of the lubricating oil of the compressor 2 and its cooling water. Moreover, the 2nd oil cooler 11 is an indirect heat exchanger of the lubricating oil of the compressor 2, and the water supply to the feed water tank 5. As shown in FIG.

In this embodiment, the coolant passes through the first air cooler 8 and the first oil cooler 10, and the coolant is circulated between the coolant 17, such as a cooling tower. That is, the cooling water cooler 17 cools the cooling water passed through the first air cooler 8 and the first oil cooler 10, and circulates the cooling water between these coolers 8 and 10.

The compressor 2, the motor 6, the oil separator 7, the first air cooler 8 and the first oil cooler 10 may be configured as the compressor unit 18 as indicated by the dashed two-dot chain lines. . In this case, a conventionally known compressor unit (including an existing and existing compressor unit) may be configured, and the air may be supplied from the compressor 2 (more specifically, the oil separator 7) to the first air cooler 8. The second air cooler 9 is installed in the 12, and the second oil cooler (in the oil passage 14 from the compressor 2 (more specifically, the oil separator 7)) to the first oil cooler 10 is installed. By providing 11), the heat recovery system 1 of the present embodiment can be configured. In addition, the dryer 13 may be further provided in the compressor unit 18.

Next, the water supply system to the boiler 4 is demonstrated. In the present embodiment, the water (soft water) from the water softener 3 passes through the second air cooler 9 and the second oil cooler 11 in sequence and then is discharged to the water supply tank 5. And the water of the water supply tank 5 is supplied to the boiler 4 via the check valve 20 by the water supply pump 19 suitably. In the boiler 4, water is heated to generate steam, which is sent to a steam use facility (not shown). Further, the water supply from the water softener 3 to the water supply tank 5 is made through the second air cooler 9 and the second oil cooler 11, but in addition to this, the water supply is directly provided without passing through these coolers 9 and 11. You may comprise so that water supply is possible.

In the heat recovery system 1 of the present embodiment, the second air cooler 9 and the second oil cooler 11 function as heat recovery heat exchangers for recovering compressed heat to produce hot water. That is, the water supply to the water supply tank 5 is heated by heat exchange with the compressed air in the second air cooler 9 and heats by heat exchange with the lubricating oil of the compressor 2 in the second oil cooler 11 to produce hot water. It is supplied to the water supply tank 5.

In the heat recovery system 1 of the present embodiment, the presence or absence of water supply to these coolers 9 and 11 based on the use load of hot water after passing through the second air cooler 9 and the second oil cooler 11. To control. In addition to or instead of this, the presence or absence of water supply to these coolers 9 and 11 is controlled based on the temperature of the hot water after passing through the second air cooler 9 and the second oil cooler 11. do.

More specifically, the water level sensor 21 is provided in the water supply tank 5. As this water level sensor 21, an electrode type water level detector, a capacitive water level detector, a float type water level detector, etc. can be used, for example. The opening and closing or opening degree of the water supply valve 23 provided in the water supply passage 22 to the water supply tank 5 is changed based on the detection signal of the water level sensor 21. For example, if there is no use load of hot water, and the water level in the water supply tank 5 exceeds the upper limit level, the water supply valve 23 may be closed, and after that, if the water level in the water supply tank 5 falls below the lower limit level, the water supply The valve 23 may be opened. Alternatively, the opening degree of the water supply valve 23 may be adjusted so that the water level in the water supply tank 5 becomes the set water level.

Instead of or in addition to the control based on the use load of such hot water, the presence or absence of the water supply to the water supply tank 5 may be controlled based on the temperature of the hot water. In this case, the temperature sensor 24 is installed in the water supply path or the water supply tank 5 after passing through both coolers 9 and 11. The opening and closing or opening degree of the water supply valve 23 provided in the water supply passage 22 to the water supply tank 5 is changed based on the detection signal of the temperature sensor 24. For example, the opening degree of the water supply valve 23 may be adjusted to maintain the detected temperature of the temperature sensor 24 at the set temperature. In addition, during this control, the water level in the water supply tank 5 is monitored by the water level sensor 21, and if the water level can be exceeded, the production of hot water is unnecessary, so that the water supply valve 23 may be closed. In this way, even if the water supply to the 2nd air cooler 9 and the 2nd oil cooler 11 is stopped, in the 1st air cooler 8 and the 1st oil cooler 10, compressed air and lubricating oil can be cooled as desired. Is as described above.

In any case, the water supply valve 23 may be provided at the outlet side of the coolers of both the second air cooler 9 and the second oil cooler 11, but the second air cooler 9 and the second oil cooler ( In consideration of the influence of water pressure and temperature applied to 11), it is preferable to be provided at the inlet side than the coolers of both the second air cooler 9 and the second oil cooler 11 as shown in the example.

As described above, the heat recovery system 1 of the present embodiment includes a second air cooler 9 and a second oil cooler 11 in addition to the first air cooler 8 and the first oil cooler 10. The predetermined air cooling is performed in the first air cooler 8 and the first oil cooler 10 even when the water supply to the water supply tank 5 is stopped through the second air cooler 9 and the second oil cooler 11. This is possibly configured. Typically, the second air cooler 9 and the second oil cooler 11 may be provided while using the first air cooler 8 and the first oil cooler 10 as existing compressor cooling systems.

According to the heat recovery system 1 of the present embodiment, hot water can be produced by recovering compressed heat in the second air cooler 9 and the second oil cooler 11. Moreover, hot water manufacture according to the use load of hot water, and hot water manufacture of desired temperature can be performed. Moreover, even if the presence or the quantity of the water which passes through the 2nd air cooler 9 or the 2nd oil cooler 11 is adjusted, the predetermined | prescribed compressed air or lubricating oil in the 1st air cooler 8 and the 1st oil cooler 10 is carried out. It can be set as the structure which does not affect cooling of the. That is, even if the presence or the amount of water passing through the second air cooler 9 or the second oil cooler 11 is adjusted, the compressed air and the lubricating oil are respectively applied to the first air cooler 8 or the first oil cooler 10. It can be lowered below the target temperature.

Example 2

2 is a schematic view showing Embodiment 2 of a heat recovery system 1 of the present invention.

The heat recovery system 1 of the second embodiment is basically the same as the heat recovery system 1 of the first embodiment. Therefore, below, it demonstrates centering around the difference of both, and demonstrates by attaching | subjecting the same code | symbol to the corresponding location.

In the first embodiment, all of the compressed air from the compressor (2) is sent to the first air cooler (8) through the second air cooler (9), but in the second embodiment whether or not through the second air cooler (9) It is configured to be able to change the distribution ratio of whether or not through the switching or the second air cooler 9. Therefore, the inlet side and the outlet side of the 2nd air cooler 9 are connected by the bypass air path 25, and the part of the air path 12 and the bypass air path 25 to the 2nd air cooler 9 is carried out. The three-way valve 26 is installed in the base. However, instead of providing the three-way valve 26, a solenoid valve or an electric valve may be provided in the air passage 12 or the bypass air passage 25 from the branch to the second air cooler 9. As a result, according to the present embodiment, when the compressed air from the compressor 2 is sent to the first air cooler 8, whether to be sent through the second air cooler 9 or not through the second air cooler 9, The distribution ratio can be adjusted.

Further, in the first embodiment, all of the lubricating oil of the compressor 2 is sent to the first cooler 10 through the second oil cooler 11, but in the second embodiment, whether or not the lubricating oil is passed through the second oil cooler 11 or not. It is configured to be able to change the distribution ratio of whether or not through the switching or the second oil cooler (11). Therefore, the inlet side and the outlet side of the 2nd oil cooler 11 are connected in the bypass oil passage 27, and the part of the oil passage 14 and the bypass oil passage 27 to the 2nd oil cooler 11 is connected. The three-way valve 38 is provided in the base. However, instead of providing the three-way valve 28, a solenoid valve or an electric valve may be provided in the oil passage 14 or the bypass oil passage 27 from the branch to the second oil cooler 11. As a result, according to the present embodiment, when the lubricant oil of the compressor 2 is sent to the first oil cooler 10, whether to be sent through the second oil cooler 11 or not through the second oil cooler 11 or the distribution ratio thereof. Can be adjusted. Other configurations and controls are the same as those of the first embodiment, so description is omitted.

Example 3

3 is a schematic view showing a third embodiment of the heat recovery system 1 of the present invention, and shows only the change points of the first embodiment or the second embodiment.

The heat recovery system 1 of the third embodiment is basically the same as the heat recovery system 1 of the first embodiment and the second embodiment. Therefore, below, it demonstrates centering around the difference of both, and demonstrates the same place attaching | subjecting the same code | symbol.

In the first embodiment and the second embodiment, both the second air cooler 9 and the second oil cooler 11 are connected in series so that water to the water supply tank 5 flows in sequence. The second air cooler 9 and the second oil cooler 11 are installed in parallel so that water to the water supply tank 5 branches and flows to the second air cooler 9 and the second oil cooler 11.

Specifically, the water supply 22 from the water softener 3 branches into the 1st water supply path 29 and the 2nd water supply path 30, and the 2nd air cooler 9 is installed in the 1st water supply path 29, The second oil cooler 11 is installed in the second water supply passage 30. In the illustrated example, the water supply valve 23 is installed just before branching to the first water supply path 29 and the second water supply path 30, but the orifice is provided in the first water supply path 29 and / or the second water supply path 30. Alternatively, a solenoid valve or an electric valve may be provided. Other configurations and controls are the same as those of the first embodiment or the second embodiment, and thus description thereof is omitted.

Example 4

4 is a schematic view showing Embodiment 4 of a heat recovery system 1 of the present invention.

The heat recovery system 1 of the fourth embodiment is also basically the same as the heat recovery system 1 of the respective embodiments. Therefore, below, it demonstrates centering around the difference of both, and demonstrates the same place attaching | subjecting the same code | symbol.

In each of the above embodiments, the compressor 2 is oil lubricated (lubricated), but in the fourth embodiment, the compressor 2 is non-lubricated (dry oil free). In this case, the compressor 2 is provided with a low stage compressor 31 and a high stage compressor 32. Then, the compressed air from the low stage compressor 31 is sent to the high stage compressor 32 through the first inter cooler 33, and further compressed in the high stage compressor 32, and the respective air coolers 9 as the after cooler 9, 8) are sent to.

Thus, a second inter cooler 34 serving as a heat recovery heat exchanger is installed in the air passage from the low stage compressor 31 to the first inter cooler 33. Similarly to the second air cooler 9 and the second oil cooler 11, the second inter cooler 34 passes water supply to the water supply tank 5 to recover the heat of compression. At this time, how to arrange the second inter cooler 34, the second air cooler 9 and the second oil cooler 11 and pass the water to the water supply tank 5 is set in a timely manner. As an example, the water supply to the water supply tank 5 is planned to pass through the second inter cooler 34, the second air cooler 9, and the second oil cooler 11 in order.

In the case of the non-lubricating compressors 31 and 32, there is a case where there is no lubricating oil in the compressor main body, but there is lubricating oil in the gear part, and it is desired to cool this. In this case, the lubricating oil in the gear box 35 is sent to the first oil cooler 10 through the oil supply pump 36, and cooled in the first oil cooler 10 and then returned to the gear portion. A second oil cooler 11 may be provided in the oil passage to the first oil cooler 10 in the same manner as in the above embodiments.

In the case of the fourth embodiment, the second coolers 34, 9 and 11 are similar to the respective embodiments based on the use load of the hot water after passing through the second coolers 34, 9 and 11 and / or the hot water temperature. The presence or absence of the feedwater to) is controlled. Other configurations and controls are the same as those in the above embodiments, and thus description thereof is omitted.

Example 5

The heat recovery system 1 of the fifth embodiment is basically the same as the heat recovery system 1 of the first and second embodiments. Therefore, below, it demonstrates centering around the difference of both, and demonstrates the same place attaching | subjecting the same code | symbol.

In the first and second embodiments, the compressor 2 is oil-lubricated (lubricated), but in the fifth embodiment, the condenser 2 is water-lubricated. In this case, lubricating water is used instead of lubricating oil in Examples 1 and 2. As a result, the first oil cooler 10 in the first and second embodiments becomes the first water cooler 10 for cooling the lubrication water, while the second oil cooler in the first and second embodiments 11 becomes a second water cooler 11 as a heat recovery heat exchanger for heating water by heat of lubricating water sent to the first water cooler 10. In addition, in the case of the water-lubricated compressor 2, the installation of each air cooler 8 and 9 may be abbreviate | omitted.

More specifically, in the case of the water-lubricated compressor 2, the compressed air from the compressor 2 is first discharged to the separator 7 (a water separator equivalent to the oil separator 7 in the first and second embodiments). Where the separation of the riders is planned. The compressed air in which the lubrication water is removed in the separator 7 is normally not passed through the air coolers 8 and 9 (that is, the installation of the air coolers 8 and 9 can be omitted). 13) is sent to the device using compressed air. On the other hand, the lubricating water separated from the compressed air by the separator 7 is appropriately sent to the first water cooler 10 to achieve the desired cooling, and then returned to the compressor 2. In the water-lubricated compressor 2, when the present invention is applied, a second water cooler 11 is installed in a water channel to the first water cooler 10, and the heat of compression in the second water cooler 11 is applied. May be recovered. Other configurations and controls are the same as those of the first and second embodiments, and description thereof is omitted.

The heat recovery system 1 of the present invention is not limited to the configuration of the above embodiments, and can be changed as appropriate. For example, in the above embodiments, it is needless to say that a water feed pump may be appropriately provided in the water feed passage 22 to the water feed tank 5. In addition, although the quantity of water which passes through the heat exchanger for heat recovery (2nd air cooler 9, 2nd oil cooler 11, 2nd inter cooler 34) was performed by adjustment of the opening degree of the water supply valve 23, Alternatively, a water supply pump may be provided in the water supply passage, and the flow rate may be adjusted by inverter control.

In each of the above embodiments, the preheating of the water supply of the boiler 4 is shown through the water supply to the water supply tank 5 of the boiler 4 in the heat recovery heat exchanger. The use of water is not limited to this and can be changed as appropriate.

In addition, in the case of the non-lubricating compressor like Example 4, since the heat of compression becomes high, steam may be obtained instead of hot water. In other words, in the heat recovery heat exchanger (especially, the downstream heat exchanger), water may be heated to generate steam. In this case, instead of controlling the water supply valve 23 based on the temperature of the hot water after passing through the heat recovery heat exchanger as in each of the above embodiments, the water supply valve 23 is based on the water level in the steam generation heat exchanger. ) Can be controlled. That is, it is good to control the presence or absence of the water supply to this heat exchanger so that the water level of a steam generating heat exchanger may be detected and it will be maintained at a predetermined water level. At this time, if the steam pressure in the steam generating heat exchanger becomes too high, in the second embodiment (FIG. 2), the three-way valve 26 (or the three-way valve 28) is switched to the existing first air cooler 8. (Or the first oil cooler 10) may be prioritized.

In the above embodiments, the first air cooler 8, the first oil cooler 10, the first inter cooler 33, and the first water cooler 10 have been described in the case of water-cooling, respectively. The dog or two or all may be air-cooled. In this case, the compressed air, the lubricating oil or the lubricating water is cooled by the air flow of the fan.

In each of the above embodiments, an example of installing the second air cooler 9 and the second oil cooler 11 (and the second inter cooler 34 in the fourth embodiment) has been described. There is no need, and any installation may be omitted as desired. For example, in Example 1 or Example 2, the installation of the second air cooler 9 may be omitted, or the installation of the second oil cooler 11 may be omitted.

In the case of a non-lubricating compressor, a compressor without any cooling system for lubricating oil may be used. In that case, the 1st oil cooler 10, the 2nd oil cooler 11, the oil passage 14, etc. are abbreviate | omitted, and the 2nd air cooler 9 and / or the 2nd inter cooler 34 collect | recovers the heat of compression. You can do it with a system that does.

In addition, in each said embodiment, the number of stages of the compressor 2 can be changed in time.

1: heat recovery system 2: compressor
7: Oil Separator 8: First Air Cooler
9: 2nd air cooler 10: 1st oil cooler
11: second oil cooler 12: by air
14: oil passage 17: coolant cooler
18 compressor unit 21 water level sensor
23: water supply 24: temperature sensor
31: low stage compressor 32: high stage compressor
33: 1st inter cooler 34: 2nd inter cooler

Claims (9)

A first air cooler for cooling the compressed air from the compressor,
A first oil cooler for cooling the lubricating oil of the compressor;
And a second oil cooler as a heat recovery heat exchanger installed in the oil passage to the first oil cooler to heat water with the heat of the lubricating oil sent to the first oil cooler. The method of claim 1,
A second air cooler in addition to the second oil cooler,
The second air cooler is a heat recovery heat exchanger installed in a blower to the first air cooler to heat water by the heat of compressed air sent to the first air cooler,
And the second air cooler and the second oil cooler are arranged to pass water in series or in parallel. The method of claim 1,
A second air cooler in place of the second oil cooler,
The second air cooler is a heat recovery system for heat recovery that is installed in the air passage to the first air cooler and heats water by the heat of compressed air sent to the first air cooler. The method according to any one of claims 1 to 3,
And controlling the presence or absence of the water supply to the heat recovery heat exchanger based on the use load of hot water after passing through the heat recovery heat exchanger. The method according to any one of claims 1 to 3,
And controlling the presence or absence of the water supply to the heat recovery heat exchanger based on the temperature of the hot water after passing through the heat recovery heat exchanger. The method according to any one of claims 1 to 3,
The compressor is an oil lubricated compressor,
An oil separator for separating lubricating oil from the compressed air discharged from the compressor,
The compressed air in which the lubricating oil is separated by this oil separator is sent to each said air cooler,
Lubricating oil from the oil separator is sent to each of the oil cooler. The method according to any one of claims 1 to 3,
The compressor is a lubricating compressor having a low stage compressor and a high stage compressor,
Compressed air from the low stage compressor is sent to the high stage compressor through a first inter cooler, further compressed in the high stage compressor, and then to each of the air coolers as an after cooler,
And a second inter cooler as a heat recovery heat exchanger installed in the air passage from the low stage compressor to the first inter cooler to heat water by the heat of compressed air sent to the first inter cooler. Heat recovery system. The method of claim 7, wherein
In the heat exchanger for heat recovery, water is heated to generate steam,
A heat recovery system characterized by controlling the presence or absence of water supply to the heat recovery heat exchanger based on the water level of the heat recovery heat exchanger. The method according to any one of claims 1 to 3,
The compressor is a water-lubricated compressor,
Lubricant water is used instead of the lubricating oil, whereby the first oil cooler becomes a first water cooler that cools the lubricating water, while the second oil cooler uses water from the heat of the lubricating water sent to the first water cooler. To a second water cooler as a heat exchanger for heat recovery,
A separator for separating lubricating water from the compressed air discharged from the compressor,
The first air cooler is not installed, and the compressed air from the compressor is discharged through the separator.

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