Patent ID: 6254843
Filing Date: 2001-07-03
Classification: B01D,C01F

Abstract:
A method of producing calcium sulfate with a flue gas scrubbing facility having a gas-liquid contactor that uses a calcium-based slurry to absorb sulfur dioxide from a flue gas containing acidic gases and produce a byproduct containing calcium sulfite precipitate, the byproduct then being accumulated in a reservoir apart from the gas-liquid contactor, the method comprising the steps of:installing an acidifier vessel and an oxidation receptacle between a source of the flue gas and the gas-liquid contactor;flowing the flue gas containing the acidic gases through the acidifier vessel;delivering the byproduct from the reservoir to the acidifier vessel so that some of the acidic gases are absorbed by the byproduct and the pH of the byproduct is sufficiently lowered to dissolve the calcium sulfite precipitate in the byproduct;delivering the flue gas from the acidifier vessel to the gas-liquid contactor where sulfur dioxide is absorbed by the calcium-based slurry;accumulating the byproduct from the acidifier vessel in the oxidation receptacle;oxidizing the calcium sulfite dissolved by the byproduct within the oxidation receptacle to convert the calcium sulfite to calcium sulfate; andremoving calcium sulfate from the oxidation receptacle.