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Sulfuric Acid Pump Internal Corrosion Broken Shaft, Cause Analysis

"Sulfuric Acid Pump Internal Corrosion Broken Shaft, Cause Analysis"


Figure 1 Sectional view of the hydraulic end of the first-stage sulfuric acid pump



Figure 2 Comparison of damaged shaft and intact shaft


Figure 3 Effect of sulfuric acid on carbon steel corrosion



Figure 4 The corroded auxiliary impeller

Figure 5 The seal width of the impeller keyway



Figure 6 Comparison of metal sulfuric acid resistance


Tantalum is the most corrosion-resistant metal available today, and it is inert to almost all organic and inorganic compounds. Its corrosion resistance is very similar to glass in that neither is suitable for hydrofluoric acid and hot alkali applications. Therefore, tantalum is commonly used with glass-lined steel reactors as patches, dip tubes, pipes, and overhead condensers.

Tantalum is inert to sulfuric and hydrochloric acid at all concentrations below 300°F. Temperatures up to 400°F have little effect, while tantalum is typically used below 500°F. Tantalum is not attacked by nitric acid at concentrations up to 98% and at temperatures of at least 212°F. Tantalum has proven itself to be completely inert in many applications. Some heat exchanger units have been in continuous use in multi-product research environments for over 40 years without gasket replacement.