Seeking advice on the selection of a differential pressure level gauge for a low-temperature recovery tower using concentrated sulfuric acid
Thread Content
There is a low-temperature recovery tower for concentrated sulfuric acid on site. Hermetically sealed. It contains concentrated sulfuric acid, with a temperature of around 160°C and a pressure inside the tank of about 163 kPa. The original magnetic flap remote transmission level gauge has a height of 2.6 meters. I now want to switch to a differential pressure level gauge. How to select a model. 1. The flange material has been determined to be 316L, which offers good corrosion resistance at room temperature; it is to be checked whether this property remains unchanged at around 160°. 2. If 316L is not used, which is better: tantalum or Hastelloy? 3. Can a single-flange diaphragm level gauge be used? 4. Other suggestions.
1. The corrosion resistance of 316L material generally remains intact at 160°C, but the actual situation depends on the concentration of concentrated sulfuric acid and the operating conditions; it is also necessary to consult data on corrosion resistance as well as recommendations from the manufacturer. 2. Tungsten materials and Hastelloy have better high-temperature and corrosion resistance than 316L, but they are also more expensive. In environments with concentrated sulfuric acid, tantalum exhibits excellent corrosion resistance, usually superior to Hastelloy, but it is also more expensive. The choice of material also depends on the specific operating conditions and budget. 3. Single-flange diaphragm level gauges can be used in environments with corrosive media and high operating temperatures, but it is necessary to ensure that the selected material can withstand the corrosion of concentrated sulfuric acid as well as the operating pressure. 4. Other suggestions: – Consider using a double-flange differential pressure level gauge, as it can compensate for the effects of pressure fluctuations within the tank. - It must have good sealing properties to prevent concentrated sulfuric acid from corroding the internal components of the level gauge. - Consider additional protective measures, such as an external protection box or special coating. - Communicate with professional instrument suppliers or manufacturers to obtain customized solutions suitable for specific operating conditions. .
Double-flange diaphragm-sealed differential pressure transmitter
Thank you. . . There’s no problem using this in general; for example, the EJA118E diaphragm-sealed differential pressure transmitter can operate at a maximum temperature of around 60 degrees Celsius. . . A high-temperature resistant one is needed
Thank you for the reply. Your advice is very helpful to me.
If you need a detailed selection guide for differential pressure transmitters, feel free to ask me and I’ll provide it for free
60℃ is the ambient temperature, so 160 is completely fine. What is the concentration of the concentrated sulfuric acid, and what material is the equipment made of?
This is the heat resistance temperature of silicone oil; the corrosion resistance of 316L needs to be considered as well. With a high concentration and a temperature of 160°C, it is likely not suitable; consider using alloys such as Hastelloy, and ask manufacturers about this.
Thank you. I saw a case where the diaphragm box made of 316L was corroded by concentrated sulfuric acid.
In practice, it’s better to use tantalum material – it doesn’t break easily, which reduces many troubles later on
The 316L diaphragm we chose has worked without any problems for many years. The temperature should be above 160°C, I guess. There’s no problem with EJA118.