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The device that uses physical methods to separate oxygen in the air to obtain nitrogen is called a nitrogen generator. There are three main types of nitrogen generators, namely cryogenic air separation, molecular sieve air separation (PSA) and membrane air separation Law. Today, the manufacturer of nitrogen generators-HangZhou Sihope technology co.,ltd. will briefly talk about the principle and advantages of pressure swing adsorption oxygen generation.

pressure swing adsorption method, namely PSA method, is to adsorb at a higher pressure to achieve gas separation, and to achieve regeneration of the adsorbent at a lower pressure. This method is based on the molecular sieve’s selective adsorption of oxygen and nitrogen components in the air to separate the air to obtain oxygen. When air is compressed and passes through an adsorption tower equipped with molecular sieves, nitrogen molecules are preferentially adsorbed, and oxygen molecules remain in the gas phase and become oxygen. When the adsorption reaches equilibrium, the nitrogen molecules adsorbed on the surface of the molecular sieve are driven out by pressure reduction or vacuum, and the adsorption capacity of the molecular sieve is restored. In order to continuously provide oxygen, the device usually has two or more adsorption towers, one tower adsorbs oxygen and the other tower desorbs, so as to achieve the purpose of continuous oxygen production.

The PSA method can produce oxygen with a purity of 80%-95%. The power consumption for oxygen production is generally 0.32kWh/Nm3～0.37kWh/Nm3, and the adsorption pressure is higher than atmospheric pressure, generally 30kPa～100kPa. The process is simple, working at room temperature, and the level of automation High, can realize unmanned management, especially good security. In the vacuum desorption process, the operating pressure of the device is low, and the container is not controlled by the pressure container specification. According to the number of adsorbers, the pressure swing adsorption process is divided into a single-tower process, a two-tower process, a three-tower process, and a five-tower process. The five-tower process pressure swing adsorption method is the most commonly used, which uses 5 adsorption beds, 4 blowers and 2 vacuum pumps to keep 2 beds in adsorption and vacuum during the whole cycle, which solves the technical problem of large-scale oxygen production.

Pressure swing adsorption oxygen production process has the following advantages: First, it adopts the automatic charging technology of atmospheric inlet pressure difference to reduce the air volume of the blower, prolong the service life of the equipment, and reduce the oxygen manufacturing cost. The second is the simple equipment, the main equipment Roots blower and vacuum pump are stable and reliable, and the service life of molecular sieve is more than 10 years without maintenance. The third is that the amount and purity of oxygen produced can be adjusted according to the actual use. The stable purity can reach 93%, and the economic purity is 80%~90%; the oxygen production time is fast, and the purity can reach 80% or more within 30 minutes; unit The power consumption is only 0.32kWh/Nm3～0.37kWh/Nm3. Fourth, the comparison of pressure swing adsorption oxygen production and cryogenic oxygen production has the following characteristics: low investment, simple process, less land occupation, less equipment, and fewer moving parts; high degree of automation, basically unmanned management can be realized; it can meet the needs of blast furnace rich Oxygen blast process requirements.