An acid pump is used when the liquid or fluid that needs to be pumped is either abrasive or corrosive and it is commonly used for applications that are acidic. The fluids that are transferred using an acid pump are nitric acid, phosphoric acid and sulphuric acid.
Since the nature of these acids is highly toxic and corrosive, the pump is designed in such a manner as to be able to resist the corrosive nature of these fluids. Moreover, they are perfectly sealed which means that there are no chances of any leakages occurring from the glands of the pump.
Amongst the many different types of acid pumps, the ones that are most famously used are the magnetic acid pumps. The working principle of this type of pump is similar to that of the centrifugal pump and the material used for its construction varies depending on the liquid that has to be transferred through it. The materials that are commonly used are DuPont tefzel linings, fiberglass reinforced polyesters and polypropylene thermoplastic.
Usually, the inner part of the pump is covered with DuPont tefzel linings as it is exposed to the corrosive acid that is being transferred. This covering enables a pump to withstand sulphuric acids that have a concentration within the range of 93-98% and it would not even require any maintenance. Those components of the pump that come into contact with the liquid are the inner casing, bearing box, shaft and impeller. Therefore, all these components are made of PFA, ETFE and PTFE and they are packed using the glass filled Teflon or carbon graphite.
The best design for an acid pump should be vapor-proof. This is because at one point in time, the acid that is present inside the pump gets heated up and gets vaporized, as it changes its form from liquid to gas. These vapors can escape through the sealants and glands even if they are sealed with non-corrosive materials.
The mag drive pumps provide the most efficient transfer of corrosive and toxic acids amongst all other pumps. They are capable of handling large quantities of such acids and provide a continuous supply. This makes them most appealing to individuals who wish to purchase a pump for the transfer of such toxic acids.