1.COMPRESSION OF ATMOSPHERIC AIR BY AIR COMPRESSOR
The free saturated air is sucked from atmosphere through a highly efficient dry-type suction filter into the first stage of the horizontal balanced opposed, lubricated screw type air compressor. Compressed air is chilled to 12 degree centigrade in a chilling unit ata temperature of 12 degree centigrade to a moisture separator where the condensed moisture gets removed before entering into Molecular Sieve Battery. Before sending the air to MOLECULAR SIEVE BATTERY, air is passed through an OIL ABSORBER where air becomes oil free.
2. PURIFICATION OF AIR BY PROCESS SKID
Chilled air passes through the Molecular Sieve Battery consisting of Twin Tower packed with Molecular Sieves to remove moisture and Carbon dioxide present in the air. Molecular Sieve Battery operates on Twin Tower System, when one tower is under production the other tower is regenerated by passing waste Nitrogen gas at 200 deg C through a reactivation heater. After interval of 8 to 10 hours, the tower under production gets exhausted and regenerated by similar process before use and thus the cycle continues. Any dust particles gets filtered in the DUST FILTER before air enters the AIR SEPARATION COLUMN.
3. COOLING OF AIR BY EXPANSION ENGINE (EXPANDER)
The process air before liquefaction in the air separation unit needs to be cooled to temperatures sub-zero (cryogenic). The main portion of the air after the process skid enters the expansion engine through the heat exchanger no. I after pre-cooling. The temperature of the air drops to around -165degC by the Expander which is a very highly efficient advanced design with Teflon piston rings and completely hydraulic mechanism with leak proof ball valves.
4. SEPARATION IF LIQUID AIR INTO OXYGEN AND NITROGEN BY AIR SEPARATION COLUMN
Chilled, Oil free and moisture free air enters into multi-pass HEAT EXCHANGER NO.I where it gets cooled to (-80) deg C by cold gained from outgoing waste Nitrogen and Oxygen. A part of air this enters a multi-pass HEAT EXCHANGER NO. II or LIQUIFIER made of special Alloy tubes. This air cools to (-170) deg C before passing through an expansion valve. Due to joule Thompson Effect, after the expansion valve. Due to joule Thompson Effect, after the expansion valve, air gets further cooled down and gets liquefied before entering into bottom column is known as rich liquid.
The rich liquid in the bottom column enters into feed tray of top column enters into feed tray of top column. Similarly the liquid nitrogen called POOR LIQUID enters into top column as a reflux & it takes away the latest heat of condensing Oxygen and gets vaporised whereas the liquid Oxygen flows down the trays of the top column into the Condenser passes through a Sub-Cooler to a LO Pump.
5. WITHDRAWAL LIQUID OXYGEN AND STORAGE IN STORAGE TANK
• Air intake filter and silencer
• Inlet guide vanes
• After cooler
• Check valve and flexible discharge compensator
• Cooling water manifold
• Drain traps on all coolers
• Compensators on air and water inlet and outlet
• Main motor
• Complete lubrication system
• Control and safety system
• Integrated modulating blow-off valve and silencer
• Clear capital costs, no surprises
• A complete plug in and run compressed air system
• Easy and low cost installation, no foundations
• Low energy consumption at full and partial load
• High reliability and peace of mind
• Low maintenance cost and service friendly
• Caring for the environment
• Completely oil-free without seal air consumption, no risk of oil-contaminated Super silenced version (optional)
Therefore agon can be required from air separation
plant by adding an air recovery unit.
(I) Air compressor: Screw/ low pressure- type:
We employ the most advanced compressor series available in the market. They have a unique combination, meeting customer requirements for low installation, operating and maintenance costs with high dependability and ease of use.
Screw typ rotary compressors are one of the most advanced and trouble free.
No other turbo type oil free compressor can match its efficiency and economy. This ensures a consistent and highly reliable source of air supply. Maintenance is extremely low.
(II) Pre – Cooling system:
The pre-cooling system is a highly efficient skid mounted equipment provided with the main purpose of cooling down the air to a temperature of 5 to 8 degrees Celsius and thus to discharge the condensed water. We are using highly reliable compressors of European origin.
(III) Universal Boschi Purifier:
The purifying system is the secondary process unit which is responsible for the removal of moisture, carbon dioxide, hydrocarbons as well as rare gases that are considered to be impurities in the process cycle of air separation. The structure essentially consists of double layered molecular sieves from “Zeochem” (Switzerland) along with alumina which acts as an adsorbent.
The process purifier is vital to the entire process and is greatly responsible for the purity of the final product i.e. Oxygen and Nitrogen in the Air separation Column. It consists of 2 skid mounted molecular sieve regeneration batteries that work on shifts and switch alternatively either manually or through a PLC control (optional).
(IV) Air separation Unit:
The Key to the entire Air separation Process lies within the Air Separation Unit (A.S.U). Here, the mixture of Oxygen and Nitrogen is separated by virtue of the difference in their liquefication temperatures.
The design and efficiency of the A.S.U determines the quality of the final product i.e. Oxygen and Nitrogen in terms of quantity and quality. The Boschi design A.S.U features highly efficient fin type aluminium heat exchangers and column, wherein the entire upper column is a packed column thus reducing the operational pressure and increasing the Oxygen, Nitrogen and Argon recovery.
Argon is recovered by a revolutionary technique employing full rectification without using the Hydrogen and De-Oxo unit thus saving further on power costs, operational costs and investment. This makes the Boschi design machines highly versatile and economical thanks to all the research and development done over the years.
(V) Turbo expander:
The Turbo expander is a gas or oil bearing expansion refrigeration turbine that is much more efficient than any other expansion device.
It works on the technique of induced cooling via expansion due to which the operational pressure of the plant is further reduced and the performance of the distillation column is stabilized for constant production and high purity.
• Argon production 8m3
/hr to 450m3
• To be attach to AIR SEPARATION COLOUMN of OXYGEN/NITROGEN Production > 500m3
/hr upto 40.000m3