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Gas purificn. removing acid, dioxin, furan and mercury@ - by adding calcium hydroxide suspension, drying, adding dry calcium hydroxide and surfactant and filtering, for energy supply and refuse incineration
Gas purificn. removing acid, dioxin, furan and mercury@ - by adding calcium hydroxide suspension, drying, adding dry calcium hydroxide and surfactant and filtering, for energy supply and refuse incineration
Purificn. involves treatment with a Ca(OH)2 suspension in a first purificn. stage and drying. Gas before and after drying is above the dew pt. of the impurities (I) to be sepd. and the dried Ca(OH)2, treated and/or mixed with (I), is removed on a dust filter. Before sepn. on the dust filter, the waste gas stream is treated with dry surfactant(s) (II) in a second purificn. stage, also above the dew pt. of (I). Pref. mixt. of dry Ca(OH)2 and (II) is added in the second stage. Gas is at least 200 deg. C, (200-250) deg. C before adding (aq.) Ca(OH)2 suspension in the first stage, pref. in a spray drier; and the mixt. of dry Ca(OH)2 and (II) is added at 130-140 deg. C. The dust filter is a cloth filter and the purified leaving gas stream is discharged by an induced draught. Pref. (II) are activated charcoal, lignite hearth furnace coke, activated Al2O3 and/or SiO2 gel and are used in at least 40, (40-60) (wt.)% of the substances added in the second stage and at least 3, (at least 5), esp. 7% of the total amt. of Ca(OH)2 + (II). USE/ADVANTAGE - Using min. amts. of additives.
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