液氨变色问题分析及解决思路探讨

Analysis and Solution of Liquid Ammonia Discoloration Problem

液氨合格品是无色透明的,当液氨外观带颜色时,会严重影响其销售价格及销售量。针对液氨带色现象进行了排查,排除了装置操作参数、油含量、脱硫剂对液氨带色的影响,初步认为是液氨中的挥发酚类所致。因此,在氨压机后增上了液氨脱色设施,以活性炭作为吸附剂,液氨脱色设施投用后,液氨不再显现红色,但后期液氨呈绿色。说明该脱色剂对挥发酚类具有一定脱除效果,但容易饱和,也说明有多种显色物质共同起作用。随后做了蒸发-冷凝试验,确认该工艺对液氨脱色有效。

Qualified liquid ammonia product is water white,no trace of other color.When liquid ammonia is colored,its selling price and sales market are severely affected.An investigation was carried out on liquid ammonia discoloration,which excluded the effects of operation parameters,oil content and desulfurizer on the color of liquid ammonia,and initially concluded the effects of volatile phenol in liquid ammonia.Therefore,the liquid ammonia decolorization facility was added after the ammonia press using activated carbon as the adsorbent.After the liquid ammonia decolorization facility was put into operation,the red phenomenon of liquid ammonia disappeared,but the liquid ammonia turned green in the later stage.It shows that the decolorizer has a certain removal effect on volatile phenols,but it is easy to saturate.It also indicated that multiple chromogenic substances work together.Then the evaporation-condensation test was carried out to confirm that the process is effective for liquid ammonia decolorization.