In order to remove the rust the owner considered physically removing the rust with unskilled labor and grinders. He calculated the cost at $10 USD per 31 foot long tube. The inside portion of the tube would be left rusted.
Acid dipping was also considered. Since acids were too dangerous to be allowed at the warehouse, the tubes would have to be sent out to a local pickling operation. The cost of loading, shipping, pickling and return shipping was more than $10 per tube and also left the tubes weakened by hydrogen embrittlement.
Remedy: The owner decided on Evapo-Rust as the method of de-rusting the pipes. After purchasing a 31 ft long, 4 ft deep tank for $2500, he added 220 gallons of Evapo-Rust. Filling the tank cost approximately $3200.
Results: With the initial 220 gallons of Evapo-Rust, the wholesaler was able to de-rust 700 tubes completely. The total weight of the tubes was approximately 66,000 pounds.
The cleaning cost per tube was $4.15 USD saving $5.85 per pipe or $4,500 USD on the entire bath.
The pipes were completely clean inside and out. The Evapo-Rust caused no health problems and incurred no disposal costs.