| 摘要 |
The invention relates to a method for obtaining ammonia from waste wate r containing NH3, at least one acid gas (CO2, H2S) and inert gases. The waste water is first led through a precleaning column and then at least partially into a complete stripping column. The product of the complete stripping column is cooled in a condenser and an aqueous condensate containing NH3, coming from the condenser, is conveyed to an NH3-stripping column. The top product of the NH 3- stripping column is brought into direct contact with circulating aqueous condensate containing NH3 in a wash column and NH3 is obtained from the top product of the wash column. A part of the bottom product of the wash column is returned to the NH3-stripping column. The temperature in the precleaning column is adjusted to below 30 to 200.degree.C in the bottom area, a partial flow of the waste wat er is provided into the top area of the precleaning column, and a second partial flow of th e waste water is guided into the precleaning column below the first partial flow. At least 80% of the NH3 from the complete stripping column is condensed in the condenser. A waste water flow is withdrawn from the complete stripping colum n, and at least part of it is cooled to temperatures of 10 to 60.degree.C. The cooled flow of waste water is then guided into the top area of the precleaning column.</SDO AB>
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