WATER RECIRCULATION IN INDUSTRIAL PROCESS OF MELAMIN PRODUCTION Russian patent published in 2015 - IPC C07D251/60 

FIELD: chemistry.

SUBSTANCE: claimed invention relates to a method of water recirculation in the industrial process of melamine production, including a wet method, which includes the water processing of a melamine melt from the process of the melamine synthesis with a water alkali solution, with water processing including quenching the melamine melt, obtained in the process of the melamine synthesis after the separation of gas with a NaOH or KOH solution, and crystallisation with obtaining the solid melamine and triazine-containing alkaline mother liquor, process of sewage water treatment, which includes the thermal processing of the said triazine-containing alkaline mother liquor, with the thermal processing being carried out at a temperature from 200 to 260°C and under pressure from 30 to 100 bar, and the recirculation process, where, at least, a part of the thermally processed alkaline mother liquor is recirculated into the wet method.

EFFECT: elaboration of the water recirculation method, which makes it possible to reduce the fresh water and/or alkaline solution consumption.

14 cl, 9 dwg, 5 ex