Mellcon Engineers Pvt. Ltd.

Okhla, Delhi

The cooled hydrogen now enters the second heat exchanger named evaporator, further cooling upto 0-3 (Deg.C) is accomplished in this hence the set dew point is adjustable. The cooling coil inside the evaporator have propelled through a refrigeration system due to low temperature in the evaporator. The moisture in the hydrogen condences and converts in water form. The water is collected in a well protected condensate collector and can be drained out when desired leaving the evaporator. Hydrogen again travels to pre-cooler where it has dual function of cooling and outgoing leaving dry hydrogen again rises to a safe temperature Hydrogen of around 25-40 (Deg C.)

This dryer provides an efficient, economical and easy to maintain method of drying compressed air and gases. The drying medium (Silica gel or Activated Alumina) is contained in two carbon steel pressure vessels.

While chamber I is drying, air is passed over an electrical heater embedded in chamber II and carries out the desorbed moisture of this chamber.

This type of system utilizes about 2-3% of the gas as a purge. It is an ideal system for gases requiring ultra low drying like dew points upto (-80C). Each column remains in line for about 6 hours. For regeneration, the desiccant is heated for about 3 hours and then cooled for another 3 hours before changeover. The operation is fully automatic.

The wet Air / Gas stream is split at the air dryer inlet through a differential distributor valve. Part of this air / gas stream is passed through an external heater and heated to a regeneration temperature of 160-180C, then it is fed to the Adsorber desiccant tower A containing Silica gel or activated Alumina / Molecular Sieves under regeneration thus removing out the moisture from the desiccant bed.
A water cooled / air cooled aftercooler condenses the desorbed moisture which is discharged regularly through the automatic drain trap . after condensation This Air/ Gas stream joins the main incoming air stream and goes for drying to the other tower B under drying.
Normally a Cycle time of 8+8 hrs is utilized to complete one cycle of operation. After each operation the changeover is effected automatically.

This type of dryer provides an outlet Dew Point of -40 deg C. The Air dryer can be supplied with standard accessarie like simplex / duplex Prefilters / Afterfilters, Flowmeters, dew point meters etc. The system is fully automatic / semi automatic , with Timer / PLC controls with feedbeck to/ from main DCS.

- Instrument air dryers for power plants Refineries & Petrochemicals , chemical & fertilizer plantsetc.

- CNG Compressed Natural Gas Drying & conditioning plants , Gas Drayers.

- Hydrogen Gas Drier for generator Cooling Application.

A refrigerated air dryer is the most commonly used. type of compressed air dryer / Gas Dryer for most plant applications for the drying of plant air and other utility gases like Seal gas , hydrogen gas for generator cooling , nitrogen Gas drying etc. where a dew point of (+2) Deg. C. at line pressure i.e. (-22 )Deg. C. at atmospheric pressure) is an acceptable norm. This Type of dryer finds application in Fly ash conveying , Seal gas Drying . General plant air , hydrogen gas dryer used in generator cooling application & Pneumatic tools operation.

As much as 2300 gallons of moisture can be removed from a100 cfm pneumatic system operating at 100 psi in 12 months of 3 shift operation, moisture which without a refrigerant air dryer, would have passed through the delicate pneumatic equipments & instruments

Mellcon Engineers are the manufacturers of complete range of Liquid Dryers, solvent dryers dehydration equipments & dehydrators Designed for removal of dissolved water from a variety of liquids critical to Industry. These dryer are designed for a continuous duty like Twin tower liquid dryer system or single tower liquid dryer system for batch operation i.e. Desiccant systems for liquid dehydration have two basic cycles:-

Drying-The removal of dissolved water from liquids is accomplished by passage of the wet liquid through a freshly reactivated packed column of granular desiccant material like silica gel, activated alumina or molecular sieves. Continuous operation is accomplished by the use of dual adsorbers, with one tower on the process stream while the other is being reactivated.

Reactivation-Reactivation is accomplished in the following steps:

• Drain the tower of liquid product
• Heat the desiccant to release water.
• Remove released water from the tower.
• Cool and refill.

The Mould Dryers MD-35kw / MD-70Kw is a compact, electric heated for drying of water- or alcohol based coating of resin, betonies or cement sand forms and cores.

ACCESSORIES FOR OUR MOULD DRYERS MD-35KW / MD-70KW Distribution box with two/four outlets, end welding flanges suitable for fixing hose with clips.

The mould Dryer MD-35KW / MD-70KW was developed to save energy . Hot air with a adjustable outlet temperature between 60 and 300 Degree C to the assembled mould after all openings (feeders and gating system) are covered. The hot air escapes through the sand of the mould and the core and dries the coating. Besides, the surface of the mould hollow cavity is steadily warm up. Because the outlet temperature of the hot air maximum 300 Deg C can amount, no crystal water from the cement sand binding agent can be removed, but the coating will be to the same temperature as temperature of the sand surface.