Cryogenic plant
Application of Cryogenic Nitrogen Plant is economically reasonable when fabricator needs not alone gaseous, but liquid nitrogen (oxygen/argon) of high purity (>99,9%) and quantity (>2000 Nm³/h).
Cryogenic plant runs together with turbo-expander under low-pressure conditions and produces the nitrogen by means of air condensation and rectification. Initially, required amount of atmospheric air is compressed in the oil-free turbocharger unit. Then cooled process air streams into duplex molecular sieve adsorption battery for simultaneous removal of air moisture, carbon dioxide and most of the hydrocarbons including acetylene. Dry and clean process air is cooled down through return flow of gaseous nitrogen and off gas in the Cold Box, which contains of main heat exchanger, rectification column, condenser/evaporator and expansion turbine. The required coldness is produced in the expansion turbine of oil-braked design.
Significant difference between boiling temperatures of air components enables the separation of nitrogen through one-step ultracold (cryogenic) rectification. Both gaseous and liquid Nitrogen are selected from the top of the rectification column and then stored in the receiver tanks under appropriate pressure.
Technical Data Cryogenic Plant*
| General parameters | |
|---|---|
| Process pressure, max | 10 bar |
| Operating pressure | ~9 bar |
| Power supply | 6 kV, 400 V, 3 Ph, 50 Hz |
| Power consumption | 1950 kWh (6.6 kV) |
| Starting time till production of GN | 10 h |
| Starting time till production of LIN | 10 h |
| Defrosting time | 8 h |
| Defrosting cycle under normal conditions | > 8 000 h |
| Space required for equipment | 330 m² |
| Total plant weight (empty) | 220 t |
| Production mode I | |
| Gaseous nitrogen (GN) | 6.000 Nm³/h |
| GN pressure at battery limit, min | 7 bar |
| GN purity | ≥ 99.99 % by vol. |
| Dew point pressure less | -70 °C |
| Production mode II | |
| Gaseous nitrogen (GN) | 5.800 Nm³/h |
| Liquid nitrogen (LIN) | 200 Nm³/h |
| GN pressure at battery limit, min | 7 bar |
| GN purity | ≥ 99.99 % by vol. |
| Dew point pressure less | -70 °C |
| Cooling water | |
| Inlet temperature | ≤ 27 °C |
| Pressure | 4-6 bar |
| Consumption | ~180 m³/h |
| *data based on the cryogenic plant with total N2 production of 6000 Nm³/h | |
References
| Company name / City | Country |
|---|---|
| Valcom Volgograd |  Russian Federation |
| Stroytransgaz Moscow | Russian Federation |
| Kuzocm Moscow | Russian Federation |
| Atlas Copco Moscow | Russian Federation |
| OAO Pigment Tambov | Russian Federation |
| Universal Pribor St. Petersburg | Russian Federation |
| DL Dannöhl Moscow | Russian Federation |
| Stroytransgaz II Moscow | Russian Federation |
| RHE Ivatsevichi | Russian Federation |
| Gazprom Izhevsk | Russian Federation |
| Gazprom Vladimir | Russian Federation |
| Gazprom Novogorko | Russian Federation |
| Gazprom Akademits | Russian Federation |
