| 摘要 |
<p>A converted feed gas comprising a first portion of the SO2-enriched stripper gas is formed. A conversion gas comprising SO3 and residual SO2 is formed by passing the converted feed gas through a plurality of catalyst beds in series, the plurality comprising at least 2 and no greater than 4 catalyst beds. A second portion of the SO2-enriched gas is introduced into at least one catalyst bed which is downstream of the most upstream catalyst bed in the plurality to fortify the SO2 concentration in the gas fed to the downstream bed. The present invention is also directed to a process for making sulfuric acid and/or ileum from a source gas comprising SO2. A conversion gas comprising SO3 and residual SO2 is formed by passing the SO2-enriched stripper gas through a plurality of catalyst beds in series. The conversion gas is combined with water vapor to form an acid product gas comprising: (a) sulfuric acid formed by a gas phase reaction between SO3 from the conversion gas and water vapor, thereby generating the heat of formation of sulfuric acid in the gas phase; (b) SO3; and (c) SO2. Heat energy from the gas phase heat of formation of sulfuric acid is recovered by transfer of heat from the acid product gas to steam or feed water in an indirect heat exchanger. The cooled acid product gas is then contacted with liquid sulfuric acid in an SO3 absorption zone to form additional sulfuric acid and/or oleum and an SO3-depleted gas comprising SO2.</p> |
