| 摘要 |
<p>Provided is a method for preparing sulfuric acid by using hydrogen sulfide. The method comprises the following steps: (1) performing a reduction-oxidation reaction between an H2S feed gas and oxygen in an oxygen-rich gas to prepare SO2, controlling residual oxygen after the reduction-oxidation reaction step at a molar percent of = 2%; (2) cooling the product acquired in step (1) to a temperature between 390°C and 430°C, then performing a catalyzed oxidation reaction with oxygen, the catalyzed oxidation reaction is performed in stages until the conversion rate of SO2 is = 98.7% or the outlet concentration of SO2 is = 550mg/Nm3; and (3) cooling the product acquired in step (2) to a temperature = 10°C above the dew point temperature of H2SO4, then further cooling to a temperature between 60°C and 120°C, collecting H2SO4 product, and subjecting the gas acquired after cooling to a coalescent separation before discharging directly into the atmosphere. Also provided is a heat exchanger, comprising a housing and several glass pipes arranged within the housing along the direction of a long axis of the housing, arching between two lateral walls thereof, and used for circulating a cooling medium; the adjacent glass pipes are connected head-to-tail, thereby forming at least one cooling medium flow path of unidirectional flow. The method provides great hydrogen sulfide removal efficiency, simple process flow, and allows for economic efficiency of apparatus and reasonable utilization of energy.</p> |
