Acid pump selection
Thread Content
The company’s original waste acid pumps were ordinary centrifugal pumps, with mechanical seals made of 316L material; however, these mechanical seals had a high leakage rate and required expensive repairs. We are seeking advice from Haiyoumen on what type of pump would be more suitable. Medium: Spent sulfuric acid (88-92% concentration). Source: Acid generated in the alkylation process using sulfuric acid. Temperature: Room temperature. Pressure: Inlet pressure: slightly positive pressure; outlet pressure: 0.3-0.5 Mpa is sufficient. Flow rate: Around 20 m3/h is sufficient. Issues: Trace mechanical impurities and rust may be present in the waste acid, so the harsh conditions of operation need to be taken into consideration. Thank you!
Is it caused by material corrosion?
The content of impurities such as rust and slag must be taken into consideration; a fluorinated centrifugal pump with double-end mechanical seals (PLAN54 flushing scheme) can be used
For the materials of the stationary and rotating rings, cemented carbide is recommended; the PLAN32 flushing scheme is suggested for flushing, and the flushing fluid should be selected based on your actual site conditions
If the company has sufficient financial resources, it can choose Flowserve’s fluorocarbon-lined pumps, equipped with RO/RO sealings and of the Plan53B type. If funding is limited, you can try Zeus or Wolong
Most of the time, leakage is caused by damage to the mechanical sealing surface or the presence of debris; sometimes by removing and cleaning the seal, it can function properly for another period of time after restoration
There is no flushing now; it’s just a mechanical seal with a single face
You get what you pay for – I understand that principle
One approach is to use a filter at the outlet; the filtered medium is then led out from the side to be used for flushing the seal. The advantage is that the filter does not need to be cleaned, as impurities are carried away by the liquid exiting from the outlet. Another option is to use the Plan12 flushing scheme, with dual filters; valves are installed on both sides of each filter, allowing for regular switching of the filters in order to clean them.