Hydronic-heating flash distillation process high-efficiency ammonia distillation tower

Abstract

The invention relates to a hydronic-heating flash distillation process high-efficiency ammonia distillation tower, which comprises a volatile ammonium salt thermal-decomposition distillation section, a fixed ammonium salt chemical-decomposition distillation section, a circular superheated water flash-distillation section, and an ammonium distillation wastewater separation tar section from the top down. A tower intercepting tray is arranged between the volatile ammonium salt thermal-decomposition distillation section and the fixed ammonium salt chemical-decomposition distillation section and is used for intercepting the direct vapor-phase ascent of the fixed ammonium salt chemical-decomposition distillation section below the tower intercepting tray and allowing ammonia distillation water to spill and flow to the fixed ammonium salt chemical-decomposition distillation section below the tower intercepting tray; and the lateral part of the tower intercepting tray is provided with an alkali solution charging port for decomposing fixed ammonium salt. The hydronic-heating flash distillation process high-efficiency ammonia distillation tower has the advantages that an alkali solution can be sufficiently utilized after ammonia is fully subjected to thermal decomposition and volatilization, and the vapor-phase concentration of a tower plate in each layer inside the tower can be reasonably distributed through two vapor-phase channel pipes arranged outside the ammonia distillation tower; and the all-ammonia content in outwards discharged wastewater can be effectively reduced and the total amount of the outwards discharged wastewater can be decreased.

Description

technical field [0001] The invention relates to an ammonia distillation tower for efficiently treating residual ammonia water in a coking plant. Background technique [0002] In coking production, the surface wet water and combined water of coking coal are converted into redundant residual ammonia water, which contains many harmful compounds such as phenol, cyanide and ammonia. Although ammonia is a fertilizer that promotes plant growth, when the ammonia-containing wastewater is discharged into rivers and lakes, it will cause eutrophication of the water body and reduce the self-purification ability of the water body. For this reason, the function of the ammonia distillation tower in the coking plant has changed from the earliest recovery of ammonia from the top of the tower to produce fertilizers, to a device that minimizes the ammonia content of the wastewater discharged from the bottom of the tower to protect the ecological environment. [0003] At present, the ammonia di...

AI Technical Summary

Problems solved by technology

[0004] 1) Only volatile ammonia is processed; this process has a high content of total ammonia in the effluent due to undecomposed and fixed ammonia;

[0005] 2) Two sets of treatment devices for volatile ammonia and fixed ammonia are installed; the process is complicated, the floor area is large, the infrastructure investment is high, and the operating cost is large;

[0007] Most of the existing ammonia distillation towers use external direct steam as the heat source, and the direct steam condensation will be mixed with the ammonia distillation wastewater, which increases the amount of discharged wastewater treatment

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