Issues with measuring acidity?

The range of pH is 0-14; you can simply calculate at which pH value the valve should be opened.

We use a mass flow meter to measure the concentration of sodium hydroxide; it should be the same as for acids, right?

Using a pH meter is completely fine; Rossmount’s products are a good choice. It should be noted that since the process medium is sulfuric acid, the electrode material should be PEEK – otherwise, prolonged use in such an environment will damage the electrode, leading to inaccurate measurements and affecting normal production.

The concentration can be measured using the conductivity of E+H

Hello, our project requires the design of a packed tower for the absorption of ammonia by sulfuric acid. Since we are not very familiar with this topic, could you please provide guidance on the considerations involved in the design process, as well as relevant physical property data for 50% sulfuric acid and ammonia? Specifically, we are interested in properties such as viscosity and surface tension of the liquids. Thank you!

The sulfuric acid concentration mentioned by the poster is not the same concept as the pH range of 1-14 indicated by a pH meter; the lower the sulfuric acid concentration, the higher the pH, and vice versa. Generally, pH applies only to dilute solutions. For solutions with a concentration of 35%, a pH test strip can be used to determine an approximate range, after which a pH meter can be used to get the exact pH value, and further attempts can be made based on that result.

Here’s a solution to this problem. In our case, it involves the flue gases from the boiler; after being sprayed with ammonia water, sulfuric acid anhydride is recovered. The process is similar in principle. Initially, pH meters were used for measurement, but they weren’t very effective – the sulfuric acid anhydride was too viscous and stuck to the probes of the pH meters, resulting in readings that were essentially constant and of no use as a reference. The correct way to measure pH is to install two sets of flanged differential pressure transmitters in the absorption tower. The flanges of these two transmitters should be at the same level, while their lower flanges should be 1 meter apart. Using the formula pressure = density * G * H, we can calculate the density Calculate it by yourself – do you understand now? We determine density based on the pressure difference; that’s how it works

The densitometer should better meet the process requirements! ! ! ! ! ! ! ! ! ! !

Upstairs, I’ve never had any experience with sulfuric acid anhydride production units. The sulfuric acid anhydride obtained through the recovery of SO2 using ammonia is in a very thick consistency, similar to the mud that forms during rain. Additionally, regarding the pH level at which the sulfuric acid anhydride reaches its final product state, if I remember correctly, it’s around pH 5. So why do you keep giving the original poster hydrometers? Can a densitometer measure the acidity of sulfuric acid AN? ? ? ? ? Furthermore, the purpose of producing AN sulfuric acid using the ammonia method is not to obtain AN sulfuric acid itself; the main goal is to prevent SO2 from being released into the atmosphere. Producing AN sulfuric acid is an environmentally friendly approach. The name of this process is ammonia-based desulfurization; if you’re not familiar with it, just search for it on Baidu. The method I’ve provided for measuring density is one that has been tested in practice, and it’s used by many companies, including my former employer. No major problems arise during normal operation. As for the issue of a gauge drifting, I would ask in return: if you insist on purchasing domestic transmitters that cost 1000 yuan each, then they will drift no matter where they’re used, right? However, it’s not enough to simply install double flanges to be completely secure; there are certain detailed requirements regarding installation and the selection of instruments. If you have questions, ask them within this forum – this reply will end here.