Ultralow-energy-consumption nitrogen making device

Abstract

The invention belongs to the technical field of nitrogen making and relates to an ultralow-energy consumption nitrogen making device. Air sequentially passes an air filter, an air compressor, a waste nitrogen heat exchanger, a water cooler, a pre-cooling unit, a molecular sieve purifier and a main heat exchanger and directly enters the bottom of a rectifying tower or is expanded and pressurized through a pressurizing turbine expanding machine and then enters the bottom of the rectifying tower, oxygen-enriched liquid air is obtained at the bottom of the rectifying tower, the oxygen-enriched liquid air passes a liquid-air subcooler, is throttled and fed to the top of a condensing evaporator, the oxygen-enriched liquid air exchanges heat with nitrogen and forms liquid nitrogen at the condensing evaporator, the liquid nitrogen flows back to the top of the rectifying tower to serve as the reflux of the rectifying tower, high-purity nitrogen is obtained at the top of the rectifying tower, the high-purity nitrogen is output to the outside through the main heat exchanger, and another path of high-purity liquid nitrogen is output to the outside through a nitrogen subcooler. The ultralow-energy consumption nitrogen making device is low in tower pressure and suitable for nitrogen making in nitrogen making industries, energy consumption can be reduced by 30%, and the air moisture content is low.

Description

technical field [0001] The invention belongs to the technical field of nitrogen production, in particular to an ultra-low energy consumption nitrogen production device. Background technique [0002] With the rapid development of glass industry, metallurgy, metal processing industry, chemical industry, new material industry and other industries, the demand for nitrogen products is increasing and the requirements are increasing. At present, the energy consumption of air separation equipment for nitrogen production is low. On the high side, due to long-term operation, reducing energy consumption has become a key element of cost savings. At present, the general practice is to partially expand, and the rest to throttle, and the output of the expander is boosted by fan braking to vent; the liquid air is not too cold or only simply exchanges heat with part of the fluid to overcool, the equipment adjustment is not flexible, or the output is surplus. Air, or the output is insufficie...

AI Technical Summary

Problems solved by technology

At present, the general practice is to partially expand, and the rest to throttle, and the output of the expander is boosted by fan braking to vent; the liquid air is not too cold or only simply exchanges heat with part of the fluid to overcool, the equipment adjustment is not flexible, or the output is surplus. If the output is insufficient, liquid nitrogen must be purchased to ensure production. With these methods and process organization, the power supply of the power supply department cannot meet the energy consumption requirements of the user's air separation equipment.

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