Nitrogen sealing settings
Thread Content
There is some confusion about nitrogen sealing recently. 1. Should the pressure point of nitrogen sealing be located on the tank instead of the nitrogen inlet pipe? The pressure in the tank is relatively stable, but the instantaneous pressure on the pipe is not. 2. Should the nitrogen discharge pipe be as thick as the liquid material pipe? The nitrogen sealing pressure in the tank is generally relatively small, about 1000pa, so the nitrogen discharge speed should not be fast. The nitrogen discharge pipe should be thicker, right? 3. Whether two storage tanks of the same material can share a set of nitrogen sealing devices? There are different opinions on this. I hope everyone can enlighten me. I also downloaded two nitrogen sealing settings from the Internet. Which one is better?
The requirements for nitrogen sealing are not particularly strict. Both of the above methods are used, and either one will work.
1. Should the pressure point of the nitrogen seal be located on the tank instead of the nitrogen inlet pipe? The pressure in the tank is relatively stable, but the instantaneous pressure on the pipe is not. Should be set on the tank. 2. Should the nitrogen discharge pipe be as thick as the liquid material pipe? The nitrogen sealing pressure in the tank is generally relatively small, about 1000pa, so the nitrogen discharge speed should not be fast. The nitrogen discharge pipe should be thicker, right? It depends on the change in the liquid head pressure caused by the instantaneous feed amount in the tank, and cannot be compared directly with the feed pipe. 3. Whether two storage tanks of the same material can share a set of nitrogen sealing devices? There are different opinions on this. I hope you can give me some advice. I also downloaded two nitrogen sealing settings from the Internet. Which one is better? Both are useful, depending on the process design requirements.
Thank you very much for your answer. In what situations do the settings in these two pictures apply?
1. Measure the pressure at the top of the tank. The pressure measurement on the nitrogen inlet pipe after the nitrogen sealing valve in Figure 2 is not very rigorous. The pressure here will be higher than the actual pressure in the tank. 2. The nitrogen inlet and outlet pipes are calculated based on parameters such as tank volume, stored materials, inlet and outlet material flow, and design nitrogen sealing pressure. A rigorous approach, such as following the API2000 standard, must also consider the pressure changes in the tank caused by rapid changes in ambient temperature, and thus add the compensation amount for nitrogen intake and exhaust. 3. There are people doing this in both pictures 1 and 2. There are many approaches based on different needs and requirements. For example, I once made a nitrogen sealing system for an industrial naphthalene storage tank. The method shown in your example is not feasible because naphthalene will crystallize, causing the self-operated nitrogen sealing valve to malfunction quickly. In short, nitrogen sealing of storage tanks sounds like a simple matter, but in fact, it needs to be treated rigorously according to different working conditions.
Find out the working principle of nitrogen sealing tank. When should nitrogen sealing be used?
The reply on the fifth floor is more rigorous, learn from it* Got it
The purpose of nitrogen sealing is to prevent air from entering the storage tank through the breathing valve under negative pressure, thereby controlling the oxygen content in the storage tank. After decompression, the nitrogen pressure can be controlled at 100-300pa, and a slightly positive pressure can be maintained.
1 is better, it is better to have independent nitrogen sealing.
The nitrogen supply pressure of our company's nitrogen sealing valve is generally set at 3KPa, and the nitrogen release pressure is generally set at 5KPa. I feel that the upstairs control is 300-500Pa, which requires too high a nitrogen supply valve and a nitrogen release valve.