| 摘要 |
A method includes a first step of, with a CO2.H2S stripper maintained to have a pressure higher than atmospheric pressure, from the ammonia-containing wastewater, discharging CO2 and H2S in a form of gas having a low moisture concentration from a tower top of the CO2.H2S stripper while discharging an ammonia-containing solution from a tower bottom of the CO2.H2S stripper; a second step of introducing the ammonia-containing solution obtained after the first step into an ammonia stripper which is maintained to have a lower pressure than that of the CO2.H2S stripper, and thereby discharging a gas rich in ammonia containing a small amount of H2S and CO2 from a tower top of the ammonia stripper while discharging water usable as industrial water from a tower bottom of the ammonia stripper; and a third step of introducing the ammonia rich gas obtained after the second step into a washing tower which is maintained to have a lower pressure than that of the ammonia stripper, and thereby discharging a wastewater containing a Na compound from a tower bottom of the washing tower while discharging a H2S-free gas rich in ammonia from a tower top of the washing tower. |
