KR20050094158A - Compact air drying system using filter - Google Patents

Abstract

The present invention relates to an integrated air drying apparatus, comprising: a compressor (80) for compressing air; An expansion nozzle (50) is provided for injecting and injecting compressed air by the compressor (80), and the air and water particles are separated by centrifugal force while the air injected through the expansion nozzle (50) turns inside. A cyclone 20 for collecting and removing the separated water particles to dry the air; A filter 10 installed at the center of the cyclone 20 to allow air to pass therethrough and to collect fine water particles from the air; The multi-stage process of separating and drying can be configured simply and efficiently to reduce energy and installation space, to save energy for cooling, and to be stable and reliable for a long time because the humidifier is simple and robust. In particular, it is possible to efficiently and economically utilize a small amount of dry air.

Description

Compact air drying system using filter

The present invention relates to an air drying apparatus, and in particular, an integrated air that is simple and integrated with a cyclone equipped with a filter to collect fine water particles, and a device such as a compressor, a vortex tube, and a heat exchanger. It relates to a drying apparatus.

In general, compressed air is widely used for industrial air conditioning and clean room construction as well as for combustion, drying, humidification and measurement in industrial processes. The moisture content contained in such compressed air has a great influence on industrial processes. For example, when a large amount of moisture is included in the combustion air, the temperature of the combustion gas is reduced to reduce the combustion efficiency, and in the drying process, the moisture content of the dry air itself directly affects the process efficiency. In addition, moisture contained in the air used for the measurement of electronics, textiles, chemicals, and precision machinery industries causes equipment malfunction. In addition, in order to impart a pleasant environment to the human body indoor air, an appropriate moisture content is required, and in the manufacture of a clean room, water particles may cause a big obstacle in the processing of precision products.

Therefore, it is necessary to properly control the moisture in the air and to remove the oil or foreign substances generated during the production of compressed air or circulating air. Reducing the moisture content in the air in this way is called a dehumidification or dehumidification process.

The moisture content in the air depends largely on the equilibrium saturation of the water at ambient temperature. Therefore, when the temperature is high, the water content in the air increases because the amount of evaporation of water increases, and conversely, the water content decreases at low temperatures. Therefore, dehumidification of high pressure air is a big problem, especially in summer, when the temperature is high and high.

Conventional techniques utilized in dehumidification processes utilize the principles of cooling, compression, absorption, adsorption, and the like. That is, when the temperature of the gas is lowered, the saturation humidity is reduced, so that the remaining moisture is condensed to remove moisture by cooling, and when the gas is compressed, the free movement distance of the water molecules is reduced to obtain the condensation effect of water. In order to dehumidify by the physical method of cooling and condensation, a device and energy for cooling and compressing the temperature of the gas below the dew point of the corresponding humidity are required.

The water contained in the gas condenses into the particulate water by the temperature drop while expanding at low temperature and high pressure. At this time, when the pressure drop is large, the cooling effect is large, and thus water is naturally separated from the gas because water in the gas condenses into water of larger particles. However, if the pressure drop is increased, the energy loss is increased by that much, the operating cost is high.

Absorption-type dehumidifier is a device that absorbs and removes moisture chemically or physically by contacting a gas to a hygroscopic solid or liquid. Among the absorbents used therein, solid absorbents include calcium chloride, calcium hydroxide, phosphorus oxide, and the like, and liquid absorbents include triethylene glycol, lithium chloride, and glycerin. In addition, the adsorption-type dampening method is a method of adsorbing moisture to an adsorbent such as silica gel, activated carbon, activated clay, and the like. Absorption and adsorption methods are expensive for absorption and adsorbents, and require expensive equipment and operation costs because regeneration is required for continuous operation. Therefore, it is selectively used in high value-added processes, such as the production of small capacity reaction gas.

As such, the conventional air drying system is using a heater that cools the air under high pressure to separate water from an independent collision filter and increases the temperature of the air again.

However, a combination of such separate systems may be reasonable when there is a large amount of air to be treated, but there is a need for a more integrated, simpler and more efficient system for smaller capacity air drying systems.

The present invention was created in order to meet the above-mentioned needs, and its object is to reduce the energy loss by operating the pressure drop low so as to be suitable for the drying of a small amount of air, and at the same time, the water generated finely by the reduction of the cooling effect. A high efficiency filter is used to collect and remove particles, and is simple and integrated with a compressor, a cooling device, a vortex tube, a cyclone and a heat exchanger equipped with the filter. It is to provide a drying apparatus.

In order to achieve the above object, the air drying apparatus of the present invention comprises a compressor for compressing air; An expansion nozzle is provided for injecting and injecting compressed air by a compressor, and the air injected through the expansion nozzle rotates inside to separate air and water particles by centrifugal force and collects the separated water particles. Cyclone to dry and remove air to dry; It is installed on the center of the cyclone filter to allow the air to pass through it to collect fine water particles from the air; and made to include.

In addition, it is installed between the compressor and the cyclone and further comprises a vortex tube inflow of the compressed air from the compressor to a part of the supercooled by the vortex rotation principle to send to the cyclone and the rest is discharged as hot air To lose.

In addition, the air inlet of the cyclone was installed in the direction of the inlet air and 30 ° to 60 ° to further comprise a shock plate to collect the primary water particles formed in the compressed air.

In addition, a portion of the compressed air before flowing into the vortex tube is sent to the pulse nozzle installed on the top of the filter through a pulse valve to be periodically sprayed on the filter to efficiently remove the filtered water in the filter of the filter Pulse valve and pulse nozzle to increase the humidity efficiency is further included.

The heat exchanger may further include a heat exchanger configured to increase the temperature of the dried air by allowing the hot air discharged from the vortex tube and the dried air to pass through the cyclone to exchange heat with each other.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 schematically shows an embodiment of an integrated air drying apparatus according to the present invention. As shown, the integrated air drying apparatus 1 includes a compressor 80, a vortex tube 30, an expansion nozzle 50, It consists of a cyclone 20, a heat exchanger 40, a pulse valve 60, and a pulse nozzle 70 having a filter 10 installed therein.

Compressed air by various types of compressors 80, for example, a rotary compressor or a reciprocating compressor, first flows into the vortex tube 30 and is supercooled as shown in FIG.

The vortex tube 30 is used as a local cooling device under special environmental conditions, and a cross-sectional view of a vortex tube 30 ′ generally used is shown in FIG. 3. As shown, the compressed air introduced into the tangential direction of the vortex tube 30 'through the inlet 31' forms a strong swirling air flow 35 '(primary vortex) and flows outward of the vortex tube 30'. Heading toward the warm air outlet 33 ', part is discharged to the warm air outlet 33' by the control valve 34 ', and the remaining air is returned from the control valve 34' to form the secondary vortex 36 '. Through the lower pressure region inside the primary vortex 35 'flow and exit to the cold air outlet 32'. In the flow (same direction, same angular velocity rotation) of the two vortices 35 'and 36' rotating in the vortex tube 30 ', the inner flow or the secondary vortex 36' is the outer flow or primary vortex. Since the time of one revolution with the air particles of 35 'is the same (the same angular velocity), the actual rotation speed of the secondary vortex 36' is slower than that of the primary vortex 35 '. The difference in the kinetic speed means that the kinetic energy is reduced, and the lost kinetic energy is converted into heat to increase the temperature of the primary vortex 35 'and the secondary vortex 36' is further lowered.

Therefore, the air discharged to the cold air outlet 32 of the vortex tube 30 is lowered in temperature, and when water falls below the dew point temperature, fine water particles are formed in the air. As such, since the vortex tube 30 is cooled by purely separation of momentum without using a heat transfer device or electric energy, the vortex tube 30 can be configured with high integration and high reliability. The hot air discharged to the hot air outlet 33 of the vortex tube 30 is used to raise the temperature of the air 90 dried through the heat exchanger 40 as described below.

The air cooled in the vortex tube 30 is injected into the specially designed cyclone 20 through the expansion nozzle 50 and expands to generate larger water particles therein.

Cyclone generally refers to the separation of solid particles or droplets suspended in a gas, the separation of solid particles suspended in a gas by a difference in particle size or specific gravity, solid particles suspended in a fluid or other It is used for separation of kinds of droplets or separation of solid particles suspended in liquids or difference in specific gravity.It is called gas cyclone when gas is a medium, and hydrocyclone when liquid is a medium. hydrocyclone). Gas cyclones and hydrocyclones differ significantly in their dimensions, but have the same basic structure. That is, like the conventional cyclone 20 'shown in FIG. 4, the cylindrical part 22' and the conical part 23 'are usually formed, and a medium such as liquid or gas is formed on the cylindrical part 22' and the side wall. It is supplied at a constant speed along the tangential direction. As a result, the descending swirling vortex 27 'is generated inside the cyclone 20', and the particles (solid particles, droplets, etc.) of large size and density contained in the medium are collected by the centrifugal force and collect on the conical wall. It is discharged to the outlet port 24 'of the vertex side of a cone called an underflow nozzle. On the other hand, the gas in the medium (if gas cyclone) or most liquids (if hydrocyclone) gathers in the center of the cyclone 20 'with small particles and small density depending on the conditions, so that the rising swirl 28' To form. This rising swirl 28 'is discharged to an overflow-finder 25' inserted at the top of the cylindrical portion 22 'of the cyclone 20'.

The cyclone 20 used in the present invention is an improvement of a conventional cyclone 20 '(Lapple type high efficiency), as shown in FIG. This feature is provided. The impact plate 21 is attached to the wall surface of the cyclone 20 to induce gas flow to the wall while maximizing the impact of air flowing into the cyclone 20, and one side of the impact plate 21 as shown in FIG. Is clogged and fixed at this time, the angle (∝) of the impact plate 21 is adjusted to achieve 30 ~ 60 ° with the direction of the inlet air. Since the impact plate 21 is installed, water particles generated while passing through the vortex tube 30 and the expansion nozzle 50 are first collected by colliding with the impact plate 21.

Further, as shown in the cyclone 20, a highly efficient filter 10 is provided in place of the conventional overflow finder 25 'shown in FIG. As such, the reason why the filter 10 is applied to the cyclone 20, which is a humidity absorbing device, is that the cooling effect is reduced when the energy loss is reduced by operating the pressure drop low. It is to be used to collect and remove the fine particles.

The filter 10 used in the present invention may be a polymer, a metal, a ceramic or the like, and its selection depends on the desired durability and processing efficiency. For example, ceramic and metal filters have a semi-permanent lifespan, and special polymers can last for two years or more.

The filter used for gas or particle separation has the function of collecting more than 99.5% of particles less than 3㎛ when the pore of the filter is about 10㎛, and the characteristics of the filter for water particles have not been reported yet. According to the results of the present invention, when the pore size of the filter is 20 to 30㎛, it shows the performance of collecting more than 80% of particles smaller than 3㎛. At this time, if the pore size of the filter is small, the filtration function of the water particles is high, and the damping effect is large.

The air injected into the cyclone 20 through the expansion nozzle 50 expands while turning in the cyclone 20, wherein the water particles contained in the air become larger particles and are separated from the cyclone 20 by centrifugal force. Collected on the outer wall side. Some of the collected water particles are discharged directly to the outlet 24, and the rest are collected on the outer wall of the filter 10 while passing through the filter 10 in the ascending swirling vortex. The collected water particles are discharged to the outlet 24 of the cyclone 20 and the dried air is discharged to the upper end of the cyclone 20 through the filter 10.

As such, the dried air discharged to the upper end of the cyclone 20 is preferably introduced into the heat exchanger 40, as shown in FIG. 1, and the temperature of the air through the heat transfer and the hot air discharged from the vortex tube 30. Is raised and transported to the required place or process.

If air contains a lot of particulate matter, the pores of the filter 10 are blocked, thereby increasing the pressure loss. In this case backwashing is required. The moisture absorption efficiency of the filter 10 depends largely on the pore and filtration speed of the filter. For example, when the pores of the filter are small and the filtration rate is low, high moisture absorption efficiency can be expected. In general, when the outer surface pore of the filter is 20 to 30 μm, air having a relative humidity of 40 ° C. and 100% when operating at a pressure of 7 bar and a filtration rate of 0.2 kPa may be damped to have a relative humidity of 10 ° C. or less than 20% relative humidity. have. In order to increase the filtration performance of the filter 10, a part of the compressed air is sent to the pulse nozzle 70 on the top of the filter 10 through the pulse valve 60 and periodically sprayed onto the filter 10. ), The filtered water is efficiently removed, so that the moisture absorption efficiency of the filter 10 is increased.

The table below shows the temperature of the air before entering the cyclone 20 and the temperature and relative humidity at the outlet of the integrated air drying apparatus 1 when the operation mode is changed with the integrated air drying apparatus 1 of the present invention. As shown in FIG. 2, the change in the operation of the cyclone 20 based on the operation of only the cyclone 20 is shown.

Table 1 shows when the air was operated at 100% relative humidity at 7bar pressure and 40 ℃, and Table 2 shows the operating when 100% relative humidity at 8bar and 40 ℃. .

Driving mode Cyclone Inlet Temperature (℃) Outlet temperature (℃) Relative Humidity (%) Ⅰ, basic cyclone 40 39 97 Ⅱ, Ⅰ + shock plate 40 38 90 Ⅲ, Ⅱ + filters 40 19 27 Ⅳ, Ⅲ + vortex tubes 34 18 22 Ⅴ, Ⅵ + Pulse Valve, Pulse Nozzle 34 19 20 Ⅵ, Ⅴ + Heat Exchanger 34 23 17

Driving mode Cyclone inlet temperature (℃) Outlet temperature (℃) Relative Humidity (%) Ⅰ, basic cyclone 40 39 97 Ⅱ, Ⅰ + shock plate 40 38 85 Ⅲ, Ⅱ + filters 40 18 20 Ⅳ, Ⅲ + vortex tubes 31 17 16 Ⅴ, Ⅵ + Pulse Valve, Pulse Nozzle 31 18 14 Ⅵ, Ⅴ + Heat Exchanger 31 24 13

In the table, it can be seen how much each device contributes to the dehumidification performance of the integrated air drying apparatus 1, in particular, if the filter 10 is installed and used in the cyclone 20, the integrated air drying apparatus ( It can be seen that it greatly helps the dehumidification performance of 1).

As described above, according to the present invention, it is possible to reduce energy and installation space by simply and efficiently constructing a multi-stage process of separating and drying in a conventional process of cooling-filtration-heating in the existing technology and saving energy for cooling It has an effect. And, since the humidity absorbing device is simple and robust, it has the advantage of being able to be used for a long time stably and reliably. In particular, when manufacturing a small amount of dry air can be used efficiently and economically.

1 is a view schematically showing the configuration of an embodiment of an integrated air drying apparatus according to the present invention,

Figure 2 is a cross-sectional view of the top of the cyclone of the integrated air drying apparatus of the present invention,

3 is a cross-sectional view showing the flow of air in a typical vortex tube,

4 is a perspective view showing the flow of air in a general cyclone.

<Description of the symbols for the main parts of the drawings>

1 --------- Integrated Air Dryer, 10 ------- Filter,

20, 20 '--- cyclone, 21 ------- shock plate,

22 '------- Cylindrical part, 23' ------ Cone part,

24, 24 '--- outlet, 25' ------- overflowfinder,

26, 26 '--- inlet, 27' ------- descending vortex,

28 '------- rising vortex, 30, 30' --- vortex tube,

31, 31 '--- inlet, 32, 32' --- cold outlet,

33, 33 '--- warmth outlet, 34' ------- regulating valve,

35 '------- 1st Vortex, 36' ------- 2nd Vortex,

40 -------- heat exchanger, 50 -------- expansion nozzle,

60 -------- pulse valve, 70 -------- pulse nozzle,

80 -------- compressor, 90 -------- dried air,

100 ------- Exhaust air.

Claims (5)

A compressor (80) for compressing air; An expansion nozzle (50) is provided for injecting and injecting compressed air by the compressor (80), and the air and water particles are separated by centrifugal force while the air injected through the expansion nozzle (50) turns inside. A cyclone 20 for collecting and removing the separated water particles to dry the air; The integrated air drying apparatus using a filter comprising a; filter (10) is installed on the center of the cyclone 20 to allow the air to pass through it to collect fine water particles from the air. According to claim 1, which is installed between the compressor (80) and the cyclone 20, the compressed air from the compressor (80) is introduced into a portion of the supercooled by the vortex rotation principle to send to the cyclone (20) The remainder of the integrated air drying apparatus using a filter further comprising a vortex tube (30) for discharging the hot air. The impact plate (21) according to claim 1 or 2, wherein the impact plate (21) is installed at the air inlet of the cyclone (20) at 30 ° to 60 ° in the direction of the inlet air to collect water particles formed in the compressed air. Integrated air drying apparatus using a filter further comprising a. The method of claim 1 or 2, wherein a part of the compressed air before flowing into the vortex tube (30) is sent to the pulse nozzle (70) installed on the filter 10 through the pulse valve 60 to periodically It further includes a pulse valve 60 and a pulse nozzle 70 to be sprayed to the filter 10 to efficiently remove the water filtered by the filter 10 to increase the humidity efficiency of the filter 10. Integrated air drying apparatus using a filter made. The heat exchanger of claim 1 or 2, wherein the hot air discharged from the vortex tube 30 and the dried air passing through the cyclone 20 exchange heat with each other to increase the temperature of the dried air. Integrated air drying apparatus using a filter further comprising (40).