Used 2200 sq ft Zirconium 702 Shell and Tube Heat Exchanger. Manufactured by Apex Engineered Products. Model Zr-28-288-2200-CS.(350) 1"OD Zr 702 tubes MAWP 150PSI @500F. CS Shell MAWP 150 PSI @500F. (2) Saddle mounted. 28.75"OD x 25'6.75"OAL. Serial #C-1112. National Board #111. Built 2012. Past use Nitric Acid.