How many nitrogen grades are there for utility applications? What is a dry gas seal?
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How many nitrogen grades are there for utility purposes, and what are the pressure levels for each? What is a dry gas seal? It would be best to have illustrations or video animations for demonstration
N2 – Nitrogen. Nitrogen is the main component of air; at room temperature and atmospheric pressure, it is a colorless, odorless, non-toxic, and non-flammable gas. Its chemical properties are inert. Apart from ammonia synthesis, nitrogen is commonly used as a shielding gas in various industries such as metallurgy, chemicals, coal, food, pharmaceuticals, electronics, and aviation. Nitrogen is produced from ambient air. The process of separating gaseous nitrogen from ambient air is achieved using specialized carbon molecular sieves (CMS); compressed air filled with CMS is used in a pair of adsorbers. When Tower A produces nitrogen, the molecular sieve in Tower B is regenerated. After about 60 seconds, the pressure at both ends reaches equilibrium. This means that compressed air is used in the most efficient way possible. Conversely, when Tower B produces nitrogen, the molecular sieve in Tower A is regenerated over a large area; this is what we refer to as the pressure swing adsorption method for producing N2 (PSA-N2). The flow diagram of the pressure swing adsorption nitrogen generation unit is as follows: Product range: Standard series; Capacity: 1–3000 Nm3/h. Standard purity: 500 ppm – 3% O2; Special purity: 5–500 ppm O2. Nitrogen pressure: 0.04–1.0 MPa. Dew point: –65°C – –45°C
In our workshop, the nitrogen pressure is 4.0 MPa at medium pressure and 1.0 MPa at low pressure. A dry gas seal is a relatively advanced type of shaft sealing device; it consists of a rotating ring and a stationary ring, with sealing gas flowing between them. Nitrogen can be used as this sealing gas
In our facility, nitrogen is classified into high-pressure nitrogen, medium-pressure nitrogen, low-pressure nitrogen, and very low-pressure nitrogen, with pressures of around 65 kilograms, 17 kilograms, 7 kilograms, and 1 kilogram respectively. Among them, low-pressure nitrogen is generally used for purging and nitrogen sealing. Medium-pressure nitrogen comes from the air separation plant, and it is turned into high-pressure nitrogen by the nitrogen compressors in our facility.