What to look for in liquid ammonia storage tank design

When designing a liquid ammonia storage tank, you need to pay attention to the following key aspects:

1. Material selection:

The material of liquid ammonia storage tanks should be selected from high-quality steel or corrosion-resistant materials to ensure that it can withstand the corrosion and storage pressure of liquid ammonia. Usually, steel materials such as 16MnDR or 09MnNiDR are widely used because of their good low-temperature toughness and welding performance.

The strength of the material also needs to be considered when selecting the material, because the higher the strength of the material, the greater the possibility of stress corrosion. Therefore, under the comprehensive consideration of operating pressure, residual stress, and safety and economy, steel with lower strength, such as Q245R, Q345R, etc., should be selected as far as possible to prevent ammonia stress corrosion.

2. Structural design:

The structure of the tank should avoid stress concentration caused by too many welds, too much concentration, asymmetric welds, weld crossings and irrational welding sequence, etc., in order to reduce the risk of stress corrosion.

Tank shape and head design should also be considered, usually choose horizontal cylindrical container, because of its moderate pressure capacity and easy to manufacture and install.

3. Manufacturing process:

The manufacturing process should avoid strong group welding, prevent biting edge, wrong edge and other defects, ensure that the surface in contact with the medium is as smooth as possible to reduce the possibility of corrosion.

After manufacturing, annealing heat treatment should be carried out to remove residual thermal stress after welding, which can greatly reduce the residual stress in the manufacturing process and improve the toughness of welded joints.

4. Safety measures:

Liquid ammonia storage tanks should be equipped with necessary safety accessories, such as pressure gauges, safety valves, liquid level gauges, etc., in order to monitor the pressure and liquid level in the tank in real time.

The storage tank should also be tested for gas tightness to ensure that it has good sealing performance to prevent liquid ammonia leakage.

In the design process, these standards and norms should be strictly followed to ensure the safety and reliability of the storage tank. In summary, the design of liquid ammonia storage tanks need to comprehensively consider the choice of materials, structural design, manufacturing process, safety measures, and follow the standards and norms and other aspects, in order to ensure the safe and efficient operation of the tank.