Strong sulphuric acid system upgrades - opportunities in acid plant retrofits

摘要

A strong sulphuric acid system is necessary for the formation of sulphuric acid via the hydration reaction of sulphur trioxide. This system is also required to carry out the mass transfer operations that capture water from ambient air or process gas in drying systems. Typically, acid plants have 2 to 4 strong acid towers with continuous exchange of acid to maintain certain concentrations and temperatures constant. Other ancillary equipment include: acid tanks, acid distributors, acid pumps, acid coolers, acid distributors, acid dilution systems, demisters, saddles packing, acid distributors, etc. NORAM Engineering focuses on upgrading sulphur-burning, metallurgical, and acid-regeneration sulphuric acid plants. Each plant has unique process, mechanical, layout, schedule and budgetary constraints that require significant engineering and ingenuity. This manuscript presents some important aspects of recent projects successfully executed by NORAM to upgrade the strong acid systems of existing acid plants. These plant upgrades achieved increased plant reliability, increased equipment longevity and better plant performance.