Process Description of SANGHI Oxygen Plant
The free atmospheric air is sucked in by a multi-stage air compressor through a filter and compressed to the working pressure. After each stage, intermediate coolers and water separators are provided. The compressed air then passes through the cascade cooler and then to the molecular sieve battery where the moisture and carbon dioxide are removed from the process air. It then passes through the exchanger No. 1 where it is cooled by the out-going waste nitrogen and product oxygen. A part of this cold air then flows through an expansion machine and the balance through the 2nd heat exchanger. An expansion valve, R1 Both these streams of air then unite in the lower pressure column where it partially liquefies, controls the ratio of the two air streams. The liquid air (rich air) then passes through the expansion valve R2 to the upper column, which is at a lower pressure than the lower column. Similarly the liquid nitrogen (poor liquid) travels from the lower column to the upper column through an expansion valve R3 where the separation of oxygen and nitrogen occurs. Nitrogen being more volatile passes out as a gas from the top of the column and this waste nitrogen flows through both the heat exchangers cooling the in-coming air. Similarly product oxygen is also passed through the two heat exchangers to cool the in-coming air and then to the filling manifold via a liquid pump. If a small amount of air is vented out from the upper column, higher purity nitrogen can also be obtained from this plant. R4 Valve is provided in order to fasten cooling during start-up. |
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Air Compressor
Air Compressor - Type - Reciprocating, Horizontal, Balance opposed, water jacketed, 3 / 4 / 5 stages, depending upon operation cycle. The air compressor is complete with interstage coolers, separators, motor and starter. |
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Skid Mounted Air
Compressor SKID MOUNTED compressor can be offered on request. |
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Foot Mounted Air Compressor |
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Skid Mounted Air Compressor |
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Molecular Sieve Battery
This is a battery of two vessels filled with Molecular Sieve type 13-X to absorb Carbon Dioxide and Moisture from process air. One vessel will be online and the other will be regenerated by Dry Nitrogen. Regeneration Heater is also provided. |
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Expansion Engine
Expansion Engine is a vertical reciprocating machine which can expand air adiabatically from operating air pressure to 5 Kgm / cm2 to produce the required cold for the Oxygen / Nitrogen plant. It greatly helps to reduce power consumption. |
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Air Seperation Unit / Cold Box
Air Seperation Unit / Cold Box consists of Distillation Column with Heat Exchangers for heat transfer between the incoming air and the out going cold Nitrogen and Oxygen. It is equipped with Expansion valves for controlling the operation of the plant. Control panel for the cold box is provided with the plant. Defrost heater for thawing plant is also provided on the cold box. It is also equipped with liquid oxygen pump which is a single cylinder equipment and delivers Bone-dry Oxygen upto pressure 165 Kg/Cm2. Cold box is insulated withperlite for minimizing cold losses and reducing power consumption. |
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Oxygen / Nitrogen Liquid Pump
The liquid pump is a horizontal reciprocating pump. It can pump cryogenic liquids such as Liquid Oxygen, Nitrogen and Argon upto 165 Kgm/Cm2 pressure normally and 250 Kgm / Cm2 pressure in special cases. The pumps are simple and requires least maintenance. |
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Ancillaries of Oxygen / Nitrogen Plants |