Self-heat utilization energy-saving drying machine

Abstract

The invention discloses a self-heat utilization energy-saving drying machine which comprises a freezing dryer, two drying towers, a regenerated air heat exchanger, an electric heater, a centrifugal booster pump, a regenerated air component after-cooler and a zero-gas-consumption drainer, and a gas circuit is controlled through a valve group. The method is characterized in that waste heat of high-temperature airflow at an outlet of a regeneration tower is recycled through a regeneration air heat exchanger and used for preheating regeneration airflow before entering an electric heater, and heating energy consumption is remarkably reduced; regeneration airflow is driven by the centrifugal booster pump to form closed circulation in the system, and flows back to an inlet after being cooled and dehumidified, so that zero gas consumption is realized; the refrigeration dryer has the functions of pre-drying inlet air and finally processing backflow regeneration air flow, and the adsorption load is reduced. Six working states of adsorption, heating regeneration, various cold blowing and the like can be flexibly realized through switching of the valve group. The device realizes gradient utilization of energy and zero loss of gas, and has the remarkable advantages of high energy-saving efficiency, stable dew point, reliable operation, high adaptability and the like.

Description

Technical Field

[0001] This invention relates to the field of air drying equipment technology, and more specifically to a self-heating energy-saving dryer. Background Technology

[0002] Compressed air is one of the most widely used power sources in industrial production. Its cleanliness and dryness directly affect the lifespan of pneumatic components, the accuracy of instrument measurements, and the stability of processes. Therefore, compressed air drying equipment is a crucial component of air source treatment systems.

[0003] Currently, common compressed air drying equipment on the market mainly includes refrigerated dryers and adsorption dryers. Among them, adsorption dryers are widely used in applications requiring high air dryness due to their advantage of achieving lower pressure dew points. Adsorption dryers typically employ a dual-tower structure, with one tower performing adsorption drying while the other tower regenerates (desorbs) the adsorbent to achieve continuous air supply.

[0004] To reduce operating energy consumption, especially compressed air loss, "zero-air-consumption" drying technology has become an important development direction in this field. Among the many zero-air-consumption models, the zero-air-consumption blower thermal adsorption dryer is currently recognized as one of the most energy-efficient products on the market. The basic principle of this type of equipment is to use a portion of the dry air from the system's own outlet or air pre-treated by a refrigerated dryer as the regeneration airflow. Driven by a built-in blower (or centrifugal booster pump), a regeneration cycle is formed within the closed system, thus avoiding the problem of traditional adsorption dryers consuming a large amount of finished dry air (i.e., "air consumption") during the regeneration process.

[0005] However, existing zero-air-consumption blower thermal adsorption dryers still have a significant drawback in terms of energy saving, mainly in the regeneration cold-blowing stage. The typical regeneration process usually consists of a heating stage and a cold-blowing stage: in the heating stage, an electric heater heats the regeneration gas flow to a relatively high temperature (e.g., around 150°C) before sending it into the regeneration tower, causing the adsorbent to desorb; in the subsequent cold-blowing stage, heating needs to be stopped, and the regeneration tower and its internal adsorbent are cooled from a high temperature to near room temperature with a room-temperature regeneration gas flow, so that it can effectively adsorb moisture when switching back to the adsorption state.

[0006] However, during the cold blowing stage, the desorbed drying tower and its internal adsorbent need to be cooled from a high temperature of approximately 150°C to near room temperature in preparation for the next round of adsorption. The large amount of ambient temperature regeneration airflow introduced to lower the tower temperature carries away all the sensible heat stored in the adsorbent and tower during the heating stage, dissipating this heat into the environment through the aftercooler. This means that a significant portion of the electrical energy input by the electric heater in the previous heating stage is ultimately not effectively used for moisture desorption (desorption mainly relies on hot air to reduce the relative humidity of the air), but is wasted as "cooling waste heat." This process leads to a decrease in overall energy efficiency, meaning that although this type of equipment achieves "zero air consumption," there is still room for further optimization in terms of overall energy efficiency.

[0007] Therefore, how to effectively recover and utilize the sensible heat released during the regeneration and cold blowing stage, and reduce the initial heating load of the electric heater, thereby achieving deeper energy saving on the basis of zero gas consumption, is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] To address the issues of significant heat waste and high energy consumption during the regeneration and cold blowing stage of existing zero-gas-consumption dryers, this invention provides a self-heating energy-saving dryer that achieves cascaded energy utilization and zero gas loss, offering significant advantages such as high energy efficiency, stable dew point, reliable operation, and strong adaptability.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A self-heating energy-saving dryer includes a refrigerated dryer, a drying tower A, a drying tower B, a regenerated air heat exchanger, a compressed air inlet, and a compressed air outlet. The air inlet of the refrigerated dryer is connected to the compressed air inlet, and the air outlet of the refrigerated dryer is connected to one end of a first pipeline and one end of a second pipeline. The other end of the first pipeline is connected to one end of a third pipeline and one end of a fourth pipeline via a tee. The other end of the third pipeline is connected to the lower end of the drying tower A, and the other end of the fourth pipeline is connected to the lower end of the drying tower B. A first valve and a second valve are respectively installed on the ends of the third pipeline and the fourth pipeline near the tee.

[0011] A fifth pipeline is fixedly connected between the third and fourth pipelines. A third valve and a fourth valve are respectively installed on the fifth pipeline. One end of a sixth pipeline is fixedly connected between the third and fourth valves. The other end of the sixth pipeline is connected to the hot flow side inlet of the regenerated air heat exchanger. The hot flow side outlet of the regenerated air heat exchanger is connected to the inlet of the regenerated gas separator after cooler. The outlet of the regenerated gas separator after cooler is connected to the compressed air inlet through a pipeline.

[0012] The other end of the second pipeline is connected to the compressed air outlet. A fifth valve and a sixth valve are installed on the second pipeline. One end of the seventh pipeline is fixedly connected between the fifth and sixth valves. The other end of the seventh pipeline is connected to the cold flow inlet of the regenerated air heat exchanger. A centrifugal booster pump is fixedly installed on the seventh pipeline. The cold flow outlet of the regenerated air heat exchanger is connected to the inlet of the electric heater via a pipeline. The upper ends of drying tower A and drying tower B are respectively connected to one end of the eighth and ninth pipelines. The other ends of the eighth and ninth pipelines are connected to one end of the tenth pipeline via a tee. The other end of the tenth pipeline is connected to the compressed air outlet. A seventh valve and an eighth valve are installed on the eighth and ninth pipelines respectively. An eleventh pipeline is fixedly connected between the eighth and ninth pipelines. A ninth valve and a tenth valve are installed on the eleventh pipeline. One end of the twelfth pipeline is fixedly connected between the ninth and tenth valves. The outlet of the electric heater is connected to the other end of the twelfth pipeline.

[0013] Preferably, one end of a thirteenth pipeline is fixedly connected to the twelfth pipeline, the other end of the thirteenth pipeline is connected to the seventh pipeline, and a bypass valve is installed on the thirteenth pipeline.

[0014] Preferably, a filter is fixedly installed at the end of the seventh pipeline near the second pipeline.

[0015] Preferably, the condensate outlet of the regenerated gas separator aftercooler is connected to a zero-gas-consumption drain.

[0016] Preferably, the refrigerated dryer is configured to simultaneously pre-dry the intake air from the compressed air inlet and cool and dry the return regeneration airflow from the outlet of the regeneration gas separator cooler.

[0017] This invention provides a self-heating energy-saving dryer with the following advantages: By introducing a regenerated air heat exchanger, the waste heat of the high-temperature exhaust gas (above 150°C) at the dryer tower outlet is efficiently recovered and used to preheat the cold regenerated airflow entering the regeneration tower. This allows the subsequent electric heater to only provide the difference in heat required to bring the preheated airflow to the target temperature.

[0018] By employing a centrifugal booster pump to drive the regeneration airflow, a closed-loop circulation is constructed within the system. Whether it is heated regeneration or cold-blown regeneration, the regeneration air used comes from the system itself. After completing the task of carrying away moisture, it is cooled, dehumidified, and returned to the inlet to participate in the treatment again, without any need for external discharge. This achieves 100% utilization of compressed air and completely eliminates the gas loss of traditional blower-heated regeneration or compressed air regeneration methods.

[0019] As a pre-drying unit, the refrigerated dryer removes most of the initial moisture from the compressed air, significantly reducing the dehumidification burden on the adsorption tower. This not only extends the adsorption cycle and reduces the regeneration frequency, but also indirectly lowers the total heat required for re-desorption due to the reduced heat of adsorption of water vapor generated during the adsorption process. The return regeneration gas is initially cooled and dehumidified in the regeneration gas separator cooler before being mixed with the inlet gas and entering the refrigerated dryer. The refrigerated dryer simultaneously cools the mixed gas, allowing its refrigeration system to operate under optimized conditions, thus improving the overall energy efficiency ratio.

[0020] By using deeply dried outlet air as the cold-blowing regeneration air source, external contaminants or moisture that may be introduced during the regeneration stage are eliminated, ensuring the purity of the regeneration process and thus guaranteeing the long-term stability of the output air dew point. Furthermore, effective pre-drying reduces the moisture load adsorbent absorbs each time. The design of the bypass pipeline and bypass valves allows for precise adjustment of the cooling rate during cold-blowing, enabling rapid cooling to shorten regeneration time while avoiding damage to the adsorbent and tower body from rapid cooling, adapting to different ambient temperatures and process requirements. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this invention or the prior art, the accompanying drawings used in the description of this invention or the prior art will be briefly introduced below.

[0022] Figure 1 A schematic diagram of the structure of this invention;

[0023] Figure 2 A schematic diagram of the structure of the present invention under the adsorption state of operating condition 1;

[0024] Figure 3 A schematic diagram of the structure of the present invention under the heating state of operating condition 2;

[0025] Figure 4 A schematic diagram of the structure of the present invention under operating condition 3, cyclic cold blowing state;

[0026] Figure 5 A schematic diagram of the structure of the present invention under operating condition 4 (cold blowing state);

[0027] Figure 6 A schematic diagram of the structure of the present invention in the waiting state of operating condition 5;

[0028] Figure 7 A schematic diagram of the structure of the present invention under operating condition 6, with two towers in parallel configuration;

[0029] Explanation of the labels in the diagram:

[0030] 1. Refrigerated dryer; 2. Drying tower A; 3. Drying tower B; 4. Regenerated air heat exchanger; 5. Compressed air inlet; 6. Compressed air outlet; 7. First pipeline; 8. Second pipeline; 9. Third pipeline; 10. Fourth pipeline; 11. First valve; 12. Second valve; 13. Fifth pipeline; 14. Third valve; 15. Fourth valve; 16. Sixth pipeline; 17. Regenerated gas aftercooler; 18. Fifth valve; 19. Sixth valve; 20. Seventh pipeline; 21. Centrifugal booster pump; 22. Electric heater; 23. Eighth pipeline; 24. Ninth pipeline; 25. Tenth pipeline; 26. Seventh valve; 27. Eighth valve; 28. Eleventh pipeline; 29. ​​Ninth valve; 30. Tenth valve; 31. Twelfth pipeline; 32. Thirteenth pipeline; 33. Bypass valve; 34. Filter; 35. Zero-air-consumption drainer. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0032] Example 1, as Figures 1 to 7 As shown, a self-heating energy-saving dryer includes a refrigerated dryer 1, a drying tower A2, a drying tower B3, a regenerated air heat exchanger 4, a compressed air inlet 5, and a compressed air outlet 6. The air inlet of the refrigerated dryer 1 is connected to the compressed air inlet 5. The air outlet of the refrigerated dryer 1 is connected to one end of the first pipe 7 and one end of the second pipe 8. The other end of the first pipe 7 is connected to one end of the third pipe 9 and one end of the fourth pipe 10 through a tee. The other end of the third pipe 9 is connected to the lower end of the drying tower A2, and the other end of the fourth pipe 10 is connected to the lower end of the drying tower B3. A first valve 11 and a second valve 12 are respectively installed on the ends of the third pipe 9 and the fourth pipe 10 near the tee.

[0033] A fifth pipeline 13 is fixedly connected between the third pipeline 9 and the fourth pipeline 10. A third valve 14 and a fourth valve 15 are respectively installed on the fifth pipeline 13. One end of the sixth pipeline 16 is fixedly connected between the third valve 14 and the fourth valve 15. The other end of the sixth pipeline 16 is connected to the hot flow side inlet of the regenerated air heat exchanger 4. The hot flow side outlet of the regenerated air heat exchanger 4 is connected to the inlet of the regenerated gas after-cooler 17. The outlet of the regenerated gas after-cooler 17 is connected to the compressed air inlet 5 through a pipeline.

[0034] The other end of the second pipeline 8 is connected to the compressed air outlet 6. A fifth valve 18 and a sixth valve 19 are installed on the second pipeline 8. One end of the seventh pipeline 20 is fixedly connected between the fifth valve 18 and the sixth valve 19. The other end of the seventh pipeline 20 is connected to the cold flow inlet of the regenerated air heat exchanger 4. A centrifugal booster pump 21 is fixedly installed on the seventh pipeline 20. The cold flow outlet of the regenerated air heat exchanger 4 is connected to the inlet of the electric heater 22 via a pipeline. The upper ends of drying tower A2 and drying tower B3 are respectively connected to one end of the eighth pipeline 23 and the ninth pipeline 24. The other ends of the eighth pipe 23 and the ninth pipe 24 are connected to one end of the tenth pipe 25 via a tee. The other end of the tenth pipe 25 is connected to the compressed air outlet 6. The seventh valve 26 and the eighth valve 27 are installed on the eighth pipe 23 and the ninth pipe 24 respectively. The eleventh pipe 28 is fixedly connected between the eighth pipe 23 and the ninth pipe 24. The ninth valve 29 and the tenth valve 30 are installed on the eleventh pipe 28. The ninth valve 29 and the tenth valve 30 are fixedly connected to one end of the twelfth pipe 31. The outlet of the electric heater 22 is connected to the other end of the twelfth pipe 31.

[0035] One end of the thirteenth pipe 32 is fixedly connected to the twelfth pipe 31, and the other end of the thirteenth pipe 32 is connected to the seventh pipe 20. A bypass valve 33 is installed on the thirteenth pipe 32.

[0036] Working principle:

[0037] Operating condition 1: In the adsorption state, such as Figure 2 As shown, the second valve 12 and the eighth valve 27 (or the first valve 11 and the seventh valve 26; depending on the drying tower selected, in this embodiment, adsorption tower B3 is selected), and all other valves are closed. The centrifugal booster pump 21 stops, and the electric heater 22 is de-energized.

[0038] The workflow is as follows: Wet compressed air enters through compressed air inlet 5, first flowing through refrigerated dryer 1 for pre-cooling and preliminary dehumidification. The pre-dried gas then enters the lower part of drying tower B3 via first pipe 7 and fourth pipe 10, flowing upwards through the adsorbent bed inside drying tower B3 for deep adsorption drying. The dried, qualified air exits from the top of drying tower B3, flows through ninth pipe 24 and tenth pipe 25, and finally exits from compressed air outlet 6.

[0039] The purpose of this operating condition is to achieve efficient and deep drying of compressed air to provide continuously dry compressed air. At this time, drying tower A2 is either saturated and ready for regeneration or awaiting regeneration.

[0040] Operating Condition 2: Under heating conditions, such as Figure 3As shown, after opening the second valve 12 and the eighth valve 27, open the fifth valve 18, the ninth valve 29 and the third valve 14, while keeping the other valves closed. Start the centrifugal booster pump 21 and start the electric heater 22 to the set power (e.g., heat the airflow to 150-180°C).

[0041] The regeneration airflow path is as follows: Wet compressed air enters from compressed air inlet 5, undergoes pre-cooling and preliminary dehumidification by refrigerated dryer 1, and then a portion of pre-cooled dry air is diverted from the second pipe 8 at the outlet of refrigerated dryer 1 as the regeneration air source. This airflow passes through the fifth valve 18, is then pressurized by centrifugal booster pump 21, and enters the cold flow side of regeneration air heat exchanger 4. Here, it is preheated for the first time by the high-temperature outlet airflow (hot flow side) from drying tower A2. The preheated airflow enters electric heater 22 and is heated a second time to the precise regeneration temperature. The high-temperature regeneration airflow passes through the twelfth pipe 31 and the eleventh pipe 28, flows through the ninth valve 29, and enters the drying tower A2 from the top to heat the adsorbent and desorb the moisture. Subsequently, the high-temperature airflow carrying a large amount of water vapor exits from the bottom of the drying tower A2, flows through the third valve 14, and then enters the hot flow side of the regenerated air heat exchanger 4 via the sixth pipeline 16 to release heat to the airflow on the cold flow side (achieving heat recovery), while being cooled for the first time. The cooled humid air enters the regenerated gas separator aftercooler 17, where it is further cooled by cooling water (secondary cooling). The dried and cooled regenerated airflow is guided back to the pipeline before the compressed air inlet 5, mixes with the inlet humid air, and re-enters the refrigerated dryer 1 for processing.

[0042] The purpose of this operating condition is to efficiently and thoroughly regenerate the saturated adsorbent by utilizing some of the dry air and recovered heat.

[0043] Operating condition 3: Under circulating cold blowing conditions, such as Figure 4 As shown, similar to the heating state, but the electric heater 22 is de-energized. The second valve 12, the eighth valve 27, the ninth valve 29, the third valve 14, and the sixth valve 19 remain open, while the fifth valve 18 is switched to the closed state.

[0044] The regeneration airflow path is as follows: humid compressed air enters from compressed air inlet 5, is pre-cooled and dehumidified by refrigerated dryer 1, then enters the lower part of drying tower B3 via first pipe 7 and fourth pipe 10, flowing upwards through the adsorbent bed inside drying tower B3 for deep adsorption and drying. The dried, qualified air flows out from the top of drying tower B3, through ninth pipe 24 and tenth pipe 25, and finally exits from compressed air outlet 6. Simultaneously, a portion of the outlet air from drying tower B3 is separated as regeneration airflow. This portion of regeneration airflow flows through second pipe 8 and sixth valve 19, and after being pressurized by centrifugal booster pump 21, it enters the cold flow side of regeneration air heat exchanger 4 via seventh pipe 20. Here, it is heated by the high-temperature outlet airflow from drying tower A2 within the cold flow side of regeneration air heat exchanger 4. It then flows through electric heater 22, but electric heater 22 is no longer powered, and the temperature no longer rises. The regenerated gas flow then passes through the twelfth pipe 31 and the eleventh pipe 28, and is introduced into the upper part of the drying tower A2 through the ninth valve 29. Under the condition of no additional heating, the shallow desorption of moisture on the surface of the adsorbent is completed by relying on the residual heat. Subsequently, the gas flow carrying moisture flows out from the bottom of the tower, and after passing through the third valve 14, it enters the hot flow side of the regenerated air heat exchanger 4 through the sixth pipe 16 to release residual heat. After being cooled a second time by the regenerated gas separator aftercooler 17, it finally returns to the front pipe of the compressed air inlet 5 to participate in the circulation.

[0045] The purpose of this operating condition is to continue purging the regeneration tower using dry, cold air and system waste heat after external heating has stopped, further removing residual moisture and starting to lower the tower temperature, while continuously recovering waste heat.

[0046] Operating condition 4: Under cold blowing conditions, such as Figure 5 As shown, the valve action is based on the valve settings in the circulating cold blowing state of operating condition 3, with the bypass valve 33 being opened additionally.

[0047] The regeneration airflow path is as follows: humid compressed air enters from compressed air inlet 5, is pre-cooled and dehumidified by refrigerated dryer 1, and then enters the lower part of drying tower B3 via first pipe 7 and fourth pipe 10. It flows upward through the adsorbent bed inside drying tower B3 for deep adsorption and drying. The dried, qualified air flows out from the top of drying tower B3 and is finally discharged from compressed air outlet 6. Simultaneously, the separated regeneration airflow passes through second pipe 8 and sixth valve 19, and is then pressurized by centrifugal booster pump 21. It is then divided into two paths in seventh pipe 20. The main path continues to flow through the cold flow side of regeneration air heat exchanger 4 for preheating. The other bypass path passes through thirteenth pipe 32 and bypass valve 33, bypassing regeneration air heat exchanger 4 and electric heater 22. The two airflows mix at the outlet of electric heater 22 (or twelfth pipe 31), forming an airflow with a temperature between ambient temperature and preheating temperature, which enters drying tower A2 for cold blowing. Subsequently, the airflow carrying moisture flows out from the bottom of the tower, passes through the third valve 14, and then enters the hot flow side of the regenerated air heat exchanger 4 through the sixth pipeline 16 to release residual heat. After being cooled a second time by the regenerated gas separator aftercooler 17, it finally returns to the front pipeline of the compressed air inlet 5 to participate in the circulation.

[0048] The purpose of this operating condition is to precisely control the temperature of the cold blowing gas entering the regeneration tower by adjusting the opening of the bypass valve 33, thereby optimizing the cooling rate of the tower body, preventing stress damage to the adsorbent caused by excessively rapid cooling, and balancing the heat recovery efficiency and regeneration cycle.

[0049] Operating condition 5: In the waiting state, such as Figure 6 As shown, the adsorption process is restored to that of Condition 1 (e.g., using drying tower B for adsorption). At the same time, all regeneration gas path valves leading to drying tower A2 are strictly closed, namely, valves 11, 14, 15, 18, 19, 29, 30 and bypass valve 33 are closed, valves 12, 26 and 27 are opened, and centrifugal booster pump 21 is stopped and electric heater 22 is de-energized.

[0050] At this time, only the main adsorption gas flow path is in operation for the regeneration gas flow. The standby drying tower A2 is in a natural static waiting state. The purpose of this operating mode is to reduce energy consumption when the system gas consumption is low or when it is on standby. The state of the adsorbent in the standby drying tower A2 (dry or partially saturated) is maintained, and adsorption can be quickly started or a complete regeneration can be initiated as needed.

[0051] Operating Condition 6: In the parallel operation of the two towers, such as Figure 7 As shown, at this time, the first valve 11, the second valve 12, the seventh valve 26 and the eighth valve 27 are opened, and the third valve 14, the fourth valve 15, the fifth valve 18, the sixth valve 19, the ninth valve 29, the tenth valve 30 and the bypass valve 33 are closed.

[0052] At this time, the regenerated airflow path is as follows: wet compressed air enters from compressed air inlet 5, is pre-cooled and dehumidified by refrigerated dryer 1, and then splits into two airflows after passing through the first pipeline 7. One airflow enters drying tower A2 through the first valve 11 for adsorption, while the other airflow enters drying tower B3 through the second valve 12 for synchronous adsorption. The two towers process the entire air volume in parallel. After the two airflows have completed adsorption, they pass through the eighth pipeline 23 and the ninth pipeline 24 respectively, and then merge into the tenth pipeline 25 through the seventh valve 26 and the eighth valve 27. Finally, they are combined into a single dry airflow and sent out through compressed air outlet 6.

[0053] The purpose of this operating condition is to prepare for the next cycle of drying tower replacement.

[0054] This invention introduces a regenerated air heat exchanger 4 to efficiently recover the waste heat from the high-temperature exhaust gas (above 150°C) at the regeneration tower outlet and use it to preheat the cold regeneration airflow entering the regeneration tower. This allows the subsequent electric heater 22 to only provide the difference in heat required to bring the preheated airflow to the target temperature.

[0055] A centrifugal booster pump 21 drives the regeneration airflow to construct a closed-loop circulation loop within the system. Whether it is heated regeneration or cold-blown regeneration, the regeneration air used comes from the system itself (cold dry air or outlet dry air). After completing the task of carrying away moisture, it is cooled and dehumidified and returned to the inlet to participate in the treatment again. There is no need to discharge it to the outside, realizing 100% utilization of compressed air and completely eliminating the gas loss of traditional blower hot regeneration or compressed air regeneration methods.

[0056] The refrigerated dryer 1, acting as a pre-drying unit, removes most of the initial moisture from the compressed air, significantly reducing the dehumidification burden on the adsorption tower. This not only extends the adsorption cycle and reduces the regeneration frequency but also indirectly lowers the total heat required for re-desorption due to the reduced heat of adsorption of water vapor generated during the adsorption process. The return regeneration gas is initially cooled and dehumidified in the regeneration gas separator cooler 17 before being mixed with the inlet gas and entering the refrigerated dryer 1. The refrigerated dryer simultaneously cools the mixed gas, allowing its refrigeration system to operate under more optimized conditions, thus improving the overall energy efficiency ratio (COP).

[0057] By using deeply dried outlet air as the cold-blowing regeneration air source, external contamination or moisture that may be introduced during the regeneration stage is eliminated, ensuring the purity of the regeneration process and thus guaranteeing the long-term stability of the output air dew point (the atmospheric pressure dew point can be stably maintained at -40℃ or even lower). Furthermore, effective pre-drying reduces the moisture load adsorbed by the adsorbent in each cycle. The design of the bypass pipeline and bypass valve 33 allows for precise adjustment of the cooling rate during cold-blowing, enabling rapid cooling to shorten regeneration time while avoiding damage to the adsorbent and tower body from rapid cooling, adapting to different ambient temperatures and process requirements.

[0058] In Example 2, as a further preferred embodiment of Example 1, a filter 34 is fixedly installed at the end of the seventh pipeline 20 near the second pipeline 8. Since the seventh pipeline 20 is the "throat" through which the regeneration gas flow enters the centrifugal booster pump 21, regardless of whether the regeneration gas source comes from the outlet of the refrigerated dryer (condition 2) or the equipment outlet (conditions 3 and 4), any pipe particulate impurities carried in the gas flow, trace amounts of oil mist generated by the refrigerated dryer, or dust from the environment, if directly entering the high-speed rotating centrifugal booster pump without interception, will cause wear, corrosion, or dynamic imbalance of the pump's internal impeller and flow channels. Therefore, in this embodiment, by adding a high-precision filter 34 at the inlet of the seventh pipeline 20, these solid and liquid impurities (typically with a precision of 1-3 μm) are effectively filtered out, providing a clean working medium for the centrifugal booster pump 21. This greatly reduces the pump's failure rate, extends its overhaul cycle and service life, ensures the continuous reliability of the entire regeneration cycle power source, and avoids regeneration failure and system downtime due to power interruption.

[0059] Furthermore, the final destination of the regeneration gas stream is to enter a drying tower (such as drying tower A) to regenerate the adsorbent. Oil (even trace amounts) and certain chemical contaminants, once in contact with the adsorbent (such as molecular sieves or activated alumina), can cause permanent blockage of its microporous structure or alter its chemical properties, leading to a sharp and irreversible drop in adsorption capacity. Therefore, the deep purification by filter 34 ensures that the gas stream entering the regeneration tower is clean, containing only the water vapor that needs to be removed. This protects the chemical activity and physical structure of the expensive adsorbent, allowing it to maintain high adsorption capacity and deep drying capability at all times.

[0060] In Example 3, as a further preferred embodiment of Example 1, the condensate outlet of the regenerated gas separator aftercooler 17 is connected to a zero-air-consumption drain valve 35. During the regeneration cycle, the regenerated gas separator aftercooler 17 condenses a large amount of water vapor into liquid water. If a conventional timed discharge or float-type drain valve is used, a portion of high-pressure dry gas is lost each time the drain valve is opened. Although this loss is small per instance, it accumulates into a considerable energy waste in a continuously circulating system. Therefore, this embodiment uses a zero-air-consumption drain valve 35. This valve effectively intercepts and recovers the valuable dry gas above the water surface while only discharging liquid condensate, returning it to the system. This ensures that no working medium (compressed air) is lost except for water. In this embodiment, the zero-air-consumption drain valve 35 preferably adopts an electronically controlled automatic or high-efficiency mechanically floating drain valve. Its drainage action is automatically triggered by the condensate level, and while discharging liquid condensate, it effectively blocks and prevents compressed air leakage, ensuring that the system achieves true zero-air-consumption operation. Those skilled in the art can select a suitable commercially available zero-gas-consumption drainer product based on the system's gas processing capacity, condensate load, and pressure rating.

[0061] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-heating energy-saving dryer, characterized in that: The equipment includes a refrigerated dryer (1), a drying tower A (2), a drying tower B (3), a regenerated air heat exchanger (4), a compressed air inlet (5), and a compressed air outlet (6). The air inlet of the refrigerated dryer (1) is connected to the compressed air inlet (5). The air outlet of the refrigerated dryer (1) is connected to one end of the first pipeline (7) and one end of the second pipeline (8). The other end of the first pipeline (7) is connected to one end of the third pipeline (9) and one end of the fourth pipeline (10) through a tee. The other end of the third pipeline (9) is connected to the lower end of the drying tower A (2), and the other end of the fourth pipeline (10) is connected to the lower end of the drying tower B (3). The third pipeline (9) and the fourth pipeline (10) are respectively equipped with a first valve (11) and a second valve (12) near the tee. A fifth pipeline (13) is fixedly connected between the third pipeline (9) and the fourth pipeline (10). A third valve (14) and a fourth valve (15) are respectively installed on the fifth pipeline (13). One end of a sixth pipeline (16) is fixedly connected between the third valve (14) and the fourth valve (15). The other end of the sixth pipeline (16) is connected to the hot flow side inlet of the regenerated air heat exchanger (4). The hot flow side outlet of the regenerated air heat exchanger (4) is connected to the inlet of the regenerated gas separator after cooler (17). The outlet of the regenerated gas separator after cooler (17) is connected to the compressed air inlet (5) through a pipeline. The other end of the second pipeline (8) is connected to the compressed air outlet (6). The second pipeline (8) is equipped with a fifth valve (18) and a sixth valve (19). The fifth valve (18) and the sixth valve (19) are fixedly connected to one end of the seventh pipeline (20). The other end of the seventh pipeline (20) is connected to the cold flow inlet of the regenerated air heat exchanger (4). The seventh pipeline (20) is fixedly equipped with a centrifugal booster pump (21). The cold flow outlet of the regenerated air heat exchanger (4) is connected to the inlet of the electric heater (22) through a pipeline. The upper end of the drying tower A (2) and the upper end of the drying tower B (3) are respectively connected to one end of the eighth pipeline (23) and the ninth pipeline (24). The other ends of the eighth pipe (23) and the ninth pipe (24) are connected to one end of the tenth pipe (25) via a tee. The other end of the tenth pipe (25) is connected to the compressed air outlet (6). The seventh valve (26) and the eighth valve (27) are respectively installed on the eighth pipe (23) and the ninth pipe (24). The eleventh pipe (28) is fixedly connected between the eighth pipe (23) and the ninth pipe (24). The ninth valve (29) and the tenth valve (30) are installed on the eleventh pipe (28). One end of the twelfth pipe (31) is fixedly connected between the ninth valve (29) and the tenth valve (30). The outlet of the electric heater (22) is connected to the other end of the twelfth pipe (31).

2. The self-heating energy-saving dryer according to claim 1, characterized in that: One end of the thirteenth pipeline (32) is fixedly connected to the twelfth pipeline (31), and the other end of the thirteenth pipeline (32) is connected to the seventh pipeline (20). A bypass valve (33) is installed on the thirteenth pipeline (32).

3. The self-heating energy-saving dryer according to claim 1, characterized in that: A filter (34) is fixedly installed at one end of the seventh pipe (20) near the second pipe (8).

4. The self-heating energy-saving dryer according to claim 1, characterized in that: The condensate outlet of the regenerated gas separator (17) is connected to a zero-gas-consumption drain (35).

5. The self-heating energy-saving dryer according to claim 1, characterized in that: The refrigerated dryer (1) is configured to simultaneously pre-dry the intake air from the compressed air inlet (5) and cool and dry the return regeneration airflow from the outlet of the regeneration gas separator (17).

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