Compressed Air DryersWhy Dry Air ?

Compressed air is used in industries for various applications in pneumatic tools, pneumatic instruments, pneumatic machines and in a variety of production processes. The consequences of using wet air are rust and scale deposits in steel pipes, increased resistance in flow, malfunctioning of process control instruments, corrosion and damage to electromagnetic valves and pneumatic system, peeling and blistering effect on spray painted surface etc. Thus it will affect the quality of product and lead to excessive maintenance cost.

Ideal compressed Air System:

Air from the compressor has excessive moisture and contaminants. The sketch below shows a typical Compressed air system to remove these damaging impurities and get Clean and Dry air. When compressed to 7Kg/cm2g the temperature of discharge air reaches around 140oC. The after cooler and Separator installed after the compressor will cool the air, and removes 90% of moisture and oil. For instance, when the compressor takes in 100 NM3/hr of ambient air at 40oC and 50% relative humidity, at 7Kg/cm2g the after cooler will condense an average of 30 liters of water in 24 hours. If the outlet air temperature from the after cooler is 40oC, it still contains 8000 ppm moisture. At 45o C compressed air contains 10,500 ppm, at 50oC, 13,500 ppm moisture which is removed by Air Dryer. Therefore, lower the temperature of air at dryer inlet, smaller would be the size of Air Drying Unit.

Compressed Air Dryers Machine

Product Description

At, SAM Gas Projects (P) Ltd, we manufacture a wide range of compressed air dryers, which are great in demand in domestic and international market. Few of them are listed below for your reference:

Heatless Type Heat of Compression (HOC) Type Internal Heat Reaction Type No Purge Loss Type

Application of Compressed Air Dryers The compressed air dryers based on PSA technology has a broad range of commercial applications. They are the following:

Replace Bottle Nitrogen. Lasers. Air Bearings. Thermal Test Equipment. Dry Boxes. Purge Electrical Boxes. Pneumatic Instru

Heatless Type Air Dryers

A heatless compressed air dryer ( drier ) is the simplest form of desiccant type gas or air dryer ( drier ) for achieving a dew point of -40°c or better for compressed air systems and other gas and air dryer ( drier ) applications.

Process - wet incoming compressed air after passing through pre filter passes through the slide piston valve assembly and is directed towards adsorber chamber i where the compressed air passes upward through the desiccant ( activated alumina / molecular sieves ). Compressed air drying takes place by adsorption. Dry compressed air from adsorber chamber is then passes through the check valve assembly and then through the after- filter to the application or work area. while compressed air is being drying in chamber the dessiccant in chamber ii where the desiccant has been wetted in the previous cycle is being simultaneously regenerated. The chamber ii is depressurized to atmosphere through the purge valve in the downward direction. A portion of the dry compressed air passes through the needle valve / orifice plate through the desiccant and flushes out the desorbed moisture. when the regeneration is complete, the purge valve is closed and the tower is slowly repressurised to line pressure for a smooth changeover. A drying period of 5 minutes provides an efficient dew point of -40°c or better (at atmospheric pressure ). In regeneration process approximately 30 seconds are required for repressurisation.mentation.

Heat Reactivated Type Air Dryers

Heat Reactivated dryers are used when one needs compressed air of very low Dew point of (-) 60oC or (-) 80o Deg C. In this design, the desiccant is regenerated at higher temperature, along with small quantity of Dry air purge. Due to purging with Dry air and thermal regeneration, residual moisture loading on desiccant becomes low and this gives very low Dew point. The Drying unit has 2-vessels filled with Activated Alumina or Molecular sieves desiccant. One vessel remains in drying cycle for 4 hours, while other vessel is simultaneously regenerated at atmospheric pressure. Around 3% flow of dryer capacity is used as purge for regeneration. Electrical heaters are provided in a central finned Stainless steel pipe in both drying vessels. Heating cycle is for 2 hours and in this time hot purge air increases desiccant temperature to around 100oC. At this temperature regeneration is complete (due to dry air purge). Dew point achieved is around (-)40oC. If still lower Dew point is required, air purging rate is slightly increased to 5% for (-)60oC and to 7.5% for (-)80oC Dew point. SAM Gas Filters A Pre-filter with automatic drain valve is provided to remove any physical moisture from compressed air before entering Air dryer. A micronic filter is also provided in the Dryer outlet to arrest any desiccant dust particles, up to 1 micron size. Thus, you get absolutely “Clean & dry compressed air”. SAM Gas Salient

Salient features:

Longer life of operation Requires less attention of operator Once installed can be operated automatically Heaters and valves are operated automatically Internal heaters provide maximum efficiency resulting in lower power

requirement. Easy maintenance

Air capacity 5 to 3000 NM3/ Hr.

Dew point (-)40oC to (-)80oC.

Operating pressure 2 to 50 kg/ cm2g.

Heat Of Compression Type Air Dryers

In this type Compressed air, directly from Air compressor discharge is taken to Air dryer inlet through insulated pipelines, at 120 deg C(minimum) temperature. This hot air is passed through one drying vessel where saturated desiccant is regenerated by this hot air. After picking up moisture from desiccant bed, the air is cooled in an intermediate cooler. Here moisture is condensed and removed by auto drain valve. Cooled to 40oC, this air passes through the second drying vessel where balance moisture gets adsorbed and Dry air comes out. Cycle time is 4 hours regeneration & 4 hours drying. After 4 hours the changeover of vessels takes place automatically. In regeneration cycle heating of the bed is only 2 hours, and thereafter the bed is cooled by Dry air. After bed cooling, Dry air is again cooled to 40oC in another cooler, and delivered out of unit as Dry air at 40deg C temp. The Dryer is fully automatic with pneumatically actuated Ball/ plug valves. A sequence timer controls operation of these valves. Desiccant used is Activated Alumina and it dries the air upto (-)40deg C Dew point. SAM Gas

Salient features:

Easy maintenance Trouble free operation Longer life of dessicants Fully automatic operation Low pressure drop Highly efficient as there is no loss of compressed air

 

Air capacity 500 to 6000 NM3/Hr.

Dew Point up to (-)40oC.

Refrigerated Type Air Dryer:

The Basic principle is the removal of moisture by cooling air to certain present temperature.

The concept of efficient cooling is removal of heat only. The air first enters into the precooler where the incoming hot air is being cooled by outgoing cold air so as to reduce the heat load of evaporator .The air from precooler enter into the evaporator where further heat is removed by boiling refrigerant like Freon.

Now the air get condensed and this moist air is passed through a moisture separator where moisture is drained out by centrifugal action of air. The moist free air enters into precooler to cool the incoming air.

Salient Features:

  Simple and compact design.   Automatic cleaning of condenser.   Efficient Power Saving.   Least pressure drop.   Easy maintenance.

Specification:

Range : 5 to 1000 Nm3/Hr Pressure : 0.5 to 12.5 Barg. Electrical Connection: 415V , 3Phase , 50 Hz Refrigerant: R22 Dew Point : (-)23ºC.

No Purge Loss Type Air Dryers

Capitalizing on our in- depth industry knowledge , we offer a wide range of No purge loss type air dryers These are used for removing water vapour without the loss of compressed air. Our range is offered in different capacities, pressure and dew point as per the client’s requirement. We ensure to test the entire range on well defined parameters to deliver the defect free and high performing dryers to the end users.

Specifications :

Capacity : 500 Nm3/Hr to 6000 Nm3/Hr Pressure : 1 Kg/cm2g to 50 Kg/cm2g. Dew Point : upto (-) 40 degC.