| 摘要 |
Process for recovering chemicals and energy from black liquor, where the bla ck liquor is gasified with CO, CO2. CH4, H2, and H2S, in gaseous form, and Na2CO3, NaOH and Na2S, in the form of drops of smelt, being principally formed. The mixture of gas and smelt is cooled, in a first stage, by direct contact with a cooling liquid, whereupon a part of the cooling liquid is volatilized, and the smelt drops are separated off and dissolved in the remaining part of the cooling liquid with the formation of a liquid bath (6) of green liquor. In a second stage, the gas is washed and saturated with moisture by direct contact with a washing liquid bath (13). After the gas has been washed in the second stage, energy in the form of thermal energy and condensation heat is recovered from the gas in an indirect condenser (16). The contact between the gas and the liquid bath (6), consisting of green liquor, in the first stage is substantially less than the contact between the gas and the washing liquid bath (13), in the second stage. This is achieved, by the gas in the first stage not being permitted to bubble through the liquid bath (6), consisting of green liquor, in contrast to the second stage, in which the gas is caused to buble through the washing liquid bath (13).
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