TNT waste acid-residual liquid recovery process and device

Abstract

The invention discloses a TNT waste acid-residual liquid recovery process and device. The production process comprises the following steps of: (1) enabling waste acid-residual liquid to stand, and separating the waste acid at the lower layer and the residual liquid at the upper layer according to the specific gravity difference; (2) separating MNT at the upper layer and a polymer at the lower layer according to the difference of the specific gravity of components in the residual liquid; and (3) mixing the separated MNT and DNT acid liquor for reproduction of TNT. According to the method disclosed by the invention, the treatment capacity of the polymer is reduced, and meanwhile, full recycling of waste acid and MNT is realized; the recovered MNT is mixed with the acidic DNT generated by a polynitrobenzene production chain, so that the melting point of the DNT can be effectively reduced, and the DNT can be better stored and reproduced; and therefore, comprehensive recovery of waste acid-residual liquid is realized on the whole, and energy conservation, emission reduction and cyclic utilization are realized.

Description

technical field [0001] The invention relates to the technical field of TNT raffinate treatment, in particular to a process and device for recovering TNT acid raffinate. Background technique [0002] The traditional TNT production adopts toluene nitration, and the mononitrotoluene in the nitration waste acid residue is easily separated from the polymer in the waste acid storage tank; the waste acid treatment adopts the traditional drum concentration, pot concentration and other old processes. In the process, the nitrotoluene and its derivatives dissolved in the waste acid are not recovered. In recent years, in order to meet the needs of environmental protection, the treatment of waste nitrotoluene nitration acid basically adopts advanced vacuum concentration and environmental protection treatment technology. In the vacuum concentration technology, all nitrotoluene and its derivatives dissolved in waste acid are recovered; The nitrotoluene and its derivatives return to the TN...

AI Technical Summary

Problems solved by technology

In recent years, in order to meet the needs of environmental protection, the treatment of waste nitrotoluene nitration acid basically adopts advanced vacuum concentration and environmental protection treatment technology. In the vacuum concentration technology, all nitrotoluene and its derivatives dissolved in waste acid are recovered; The nitrotoluene and its derivatives return to the TNT nitration unit; the operating temperature of the vacuum concentration unit is low, and some nitro derivative impurities dissolved in the waste acid cannot be eliminated, and the impurities are nitrated with the recovered sulfuric acid——waste acid vacuum concentration treatment The cyclic accumulation of the device changes the polymer in the waste acid residue, the polymer particle size becomes finer, and disperses in mononitrotoluene to form a colloid, which is not easy to separate in the large waste acid storage tank, and the mononitrotoluene of the polymer is mixed Toluene cannot be recycled

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