PROCESS AND APPARATUS FOR PREVENTION OF CORROSION IN A MULTIPLE CONTACT-MULTIPLE ABSORPTION URIC ACID MANUFACTURING OPERATION

摘要

The addition of external heat to a gas stream in duct work passing from the intermediate absorber to the heat exchanger employed to raise the temperature of the gas stream containing residual sulfur dioxide to its catalytic initiation temperature in a multiple contact/ multiple absorption process for the manufacture of sulfuric acid in an amount sufficient to maintain the gas stream above the dew point of sulfuric acid is employed to eliminate corrosion in both the ductwork and the heat exchange(s). There may also be provided in the heat exchanger immediately following intermediate absorption, a zone maintained at a temperature above the condensation temperature of sulfuric acid to prevent condensation of acid mist on heat exchanger surfaces.