Relationship between operating temperature of liquid ammonia spheres and pipelines and extreme minimum temperatures
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Temperature: The annual average temperature is 3.9°C; the extreme maximum temperature is 34.7°C, while the extreme minimum temperature is -27.9°C. The average temperature in the hottest month is 16.2°C (July), and it is -10.9°C in the coldest month (January). 1. It is a 400m3 full-pressure liquid ammonia sphere tank without insulation – how can the operating pressure and operating temperature be determined? II. The liquid ammonia pipelines (insulated) for entering and leaving this liquid ammonia spherical tank have a length of 200 m; how should the operating pressure and operating temperature be determined? III. What is the relationship between the design temperature of liquid ammonia spherical tanks and the extreme minimum temperature (-27.9°C) as well as the average temperature of the coldest month (-10.9°C)?
What is the relationship between the design temperature of liquid ammonia spherical tanks and the extreme minimum temperature (-27.9°C) as well as the average temperature of the coldest month (-10.9°C)?
The design pressure of the spherical tank is 2.2 MPa, with a design temperature of 80/–33°C. By using these temperature and pressure values, the required operating conditions can be met; operation is hardly affected by the ambient temperature.
What is the relationship between the design temperature of a 400m3 liquid ammonia sphere tank (without insulation) and the extreme minimum temperature of -27.9°C sowie the average temperature during the coldest month of -10.9°C? It would be best to explain what the basis is
The design temperature for liquid ammonia spheres must take into account both the scenario of liquid ammonia leakage and the scenario of initial filling. When liquid ammonia leaks into the atmosphere, the operating temperature is -33.5 degrees; therefore, the design temperature is set at -35 degrees up to +50 degrees.
If leakage conditions are not taken into account and ordinary carbon steel is used, once a leak occurs, the leak site will progress from a small hole to a brittle fracture, eventually turning into a large crack. It caused a large number of leakage incidents. Why do major leaks often occur in liquid ammonia pipelines and tanks? The reason is that the leakage condition was not considered, resulting in a design using ordinary carbon steel. Safety supervision agencies have been gradually paying attention to this issue since 2007. Currently, the new liquid ammonia pipelines and liquid ammonia spherical tanks built by CNPC, Sinopec, and CNOOC are all designed using low-temperature carbon steel.
The design temperature for liquid ammonia spheres is the extreme minimum temperature of -27.9°C, minus another 15°C or so to account for the average temperature during the coldest month, which is -10.9°C; the operating temperature and pressure can be determined based on the process requirements
Are there any special requirements for ammonia storage tanks?