The invention discloses synchronous desulfurization and
denitrification technology of
coal-fired
flue gas by taking
hydrogen sulfide as a
reducing agent. The technology comprises the following steps: 1) preparation of dissolved H2S; 2) preparation of a
mixed gas of H2S, NO, NO2, and SO2; and 3) synchronous desulfurization and
denitrification. According to the technology, integration of a desulfurization and
denitrification device is authentically realized. NO and NO2 in the
coal-fired
flue gas are converted into N2 and water; SO2 and H2S are converted to high-purity elemental
sulfur; and organic matters in waste water are further removed, so that treatment of wastes with other wastes is realized. Elemental
sulfur is recycled through the technology; one part of elemental
sulfur is cycled and utilized to maintain equipment operation; and the other part of elemental sulfur is output as a product. The
reducing agent of H2S in the technology is prepared from an in-situ product of elemental sulfur through reduction, can be prepared when used, and does not need to be bought outside. Therefore, cost of purchase, transportation, and storage and potential security risk are avoided. Compared with a mainstream device, the desulfurization and denitrification device is significantly lower with respect to
land occupation, construction cost, operation cost, and the like.