二步法三聚氰胺热气冷却单元的新工艺

New Technology of the Two-Step Melamine Hot Air Cooling Unit

在两步法三聚氰胺工艺生产中,由于热气过滤单元温度高,产出的粗品三聚氰胺纯度低,副产物多,需要在精制过程中利用蒸汽,重新加热溶解粗品三聚氰胺,并送入结晶塔降温结晶,得到纯度高的三聚氰胺成品,此过程消耗了大量的蒸汽,增加了生产成本。提出了一种新的生产工艺,首次在二步法三聚氰胺工艺中增加了热气冷却单元,降低了热气温度,并副产了部分蒸汽,分离出了高沸点反应副产物,净化了热气,得到了纯度高的粗品三聚氰胺,同时改变了精制工艺,极大地降低了蒸汽消耗,节约了生产成本,提高了产品市场竞争力。

In the two step process of production of melamine,as the hot air filter unit temperature was high,there were some by-products in the crude melamine which purity was low,the crude melamine should be heated and dissolved again using of steam in the refining process,then cooled and crystallized in the crystallization tower,finally,the high purity melamine product was obtained.In this process,a large amount of steam was consumed,the production cost was increased.A new process was proposed in the two step process.The hot air cooling unit was added for the first time.The temperature of the hot air was reduced,and the by-product steam was isolated from the high boiling point reaction by-products,the air was purified,at the same time,the high purity crude product of melamine was got.Because of the change of the refining process,the consumption of steam was greatly reduced,the production cost was saved,the market competitiveness of products was improved.