The formation of methyl mercaptan and dimethyl sulfide in the digester may be treated as consecutive-competing parallel reactions. The formation of methyl mercaptan leads with the reaction of hydrogen sulfide with lignin-methoxy groups. Before methyl mercaptan can be substantially consumed by the parallel reaction of methyl mercaptan ion and lignin-methoxy groups, the cook is done, the digester is degassed and blown. If methyl mercaptan in the LVHC-NCG gas is separated in a white liquor scrubber and returned to the proceeding digester, the methyl mercaptan will react preferentially with "virgin" lignin and displace hydrogen sulfide, overall. Consequently, sulfur emissions at the incinerator (destructor) can be reduced by as much as 66 percent.
展开▼
