Airro Engineering Co.

ammonia cracker gas generator produces mixture of hydrogen and nitrogen which is commonly used in heat treatment furnaces. Ammonia gas from cylinders is passed over a bed of nickel catalyst at 850 degree celcius temperatures and cracking takes place into its basic constituents i. E. 75% h2 & 25% n2.

ammonia cracking reaction is endothermic and hence it requires heat from outside source. The source is electrically heated type furnace (rectangular shape) and a retort made of heat resistant provided inside to hold the catalyst.

Oxygen Gas Generators are based on the PSA technology. A special grade of synthetic Zeolite, known as molecular sieves is used to separate oxygen from atmospheric air. Oxygen generator consists of two adsorption vessels, filled with molecular sieves are alternately charged with compressed air up to 5 bar pressure. Nitrogen is adsorbed and enriched oxygen flows to the surge tank. After the adsorption cycle, one bed is depressurized to atmospheric pressure, thereby evacuating nitrogen and sieve bed gets regenerated completely by counter current oxygen flow from the other bed.

FEATURES

1) Operation is cyclic and automatic.

2) Automatic start-up and shut-off.

3) Working life of molecular sieves is almost 10 years on continuous run of .... the plant.

4) Very low maintenance cost.

We design and manufacture various types of pressure vessels, air / gas receiver tanks and other purpose equipments for various industries.

We also manufacture pressure vessels / equipments with required dimensions of customers. We do the hydro-test of the vessels and then dry it quickly with the pneumatic air to prevent rusting.

We also make red-oxides coats and colors as per customer's requirements.

Heat reactivated dryer are used when one needs air of very low dew point. In this design desiccant is regenerated at higher temperature with little dry air purge. Due to dry air purge and thermal regeneration, residual moisture loading on desiccant becomes low and this gives low dew points.

The drying unit has 2- vessels filled with activated alumina desiccant. One vessel remains in drying cycle for 4-hours while other vessel is simultaneously regenerated at atmospheric pressure. Around 3 to 5% flow of air dryer capacity is used as purge for regeneration. Electrical heaters are provided in a central finned stainless pipe in drying vessels. Heating cycle is for 2-hours and in this time desiccant temperature increase up to 100 to 150 degree celcius. at this temperature regeneration is complete. Dew point achieved is around and above (-) 60 degree celcius.

These dryers are some more costly than heatless type but are more suitable for Dew points lower than (-) 60 degree celcius to

(-) 80 degree celcius and purge loss is also less than the Heatless type i.e. around 3 %.

FEATURES

1. A fully automatic unit requiring no attention of the operator. Heaters switch on/off and all valves operation is fully automatic.

2. Low purge air requirement as compared to heat less type dryers.

3. Counter-current preheated dry air purge provides maximum removal of adsorbed moisture with minimum gas purge loss.

4. As heating is done desiccant life increases because moisture is removed effectively due to heating.

Wet incoming compressed air or gas is passed through a desiccant bed; the desiccant adsorbs its moisture. After some time of operation, this desiccant gets saturated and needs regeneration. Reactivation or regeneration of desiccant is then necessary to drive-off the adsorbed moisture and to re-store its original adsorptive capacity. This is accomplished via purging the adsorbent by dry air or gas at atmospheric pressure and temperature in reverse direction.

FEATURES

Low initial installation and operating cost.

High performance and almost Zero maintenance cost.

Low temperature operation which reduces corrosion of towers.

Only single phase electric power is required.

Desiccant life around 3 – 5 years.

Adsorption is a surface phenomenon on the available surface area of activated alumina. The molecules are adsorbed from gas/liquid phase and remair on activated alumina. The adsorption takes place both under static & dynamic conditions. The static adsorption capacity is denoted by the equilibrium capacity at specific relative humidity. Most applications of adsorbents, however take place under dynamic condition where the activated alumina is operated at less than the equilibrium capacity depending on design conditions.
The regeneration of activated alumina is done to desorb the adsorbate and bring it back to active form. It can be carried out by Thermal, Vacuum or Pressure swing method except when activated alumina is used for chemisorption applications.
The molecules desorbed by any method are removed from the column by a cold dry purge. The purge gas should be dry.

Nitrogen Gas Generators produces Nitrogen gas from atmospheric air by PSA (Pressure Swing Adsorption) Technology. PSA Technique is a simple & reliable process of separation of Nitrogen from compressed atmospheric air by adsorption of oxygen over a bed of Carbon Molecular Sieves (CMS). CMS is an adsorbent having infinite number of small pores. The diameter of the “Bottle Necks” is in the same range as those of the molecules.

Thus when CMS is used in the PSA process, an Oxygen Molecule, having a smaller diameter than a Nitrogen molecule traps in to the pores. Therefore the Nitrogen is recovered to a high degree while almost all the oxygen is adsorbed.

ADVANTAGES

• Electronic Programmable Control Panel (PLC System).
• Automatic start and stop.
• Highly reliable to run un-attended for months.
• Very low maintenance cost.
• Nitrogen gas supply always under your control.
• Self-contained Skid Mounted Units for easy site installation.
• Carbon Molecular Sieves life is minimum 10-12 years.