煤制气黑水总氮测定如何避免消解损失研究

How to Avoid Digestion Loss in the Determination of Total Nitrogen in the Black Water from Coal Gasification?

采用碱性过硫酸钾紫外分光光度法检测150 kt多碳醇项目产生的煤制气黑水总氮含量,总氮检测结果低于其氨氮的检测结果与理论不符。最直接原因是在采用碱性过硫酸钾紫外分光光度法检测总氮时,消解过程当中会有部分氨氮的损失,当水样氨氮含量越高,消解的损失就会越大,导致总氮含量低于氨氮含量。通过将水样蒸馏预处理脱除水样中氨氮,再对蒸馏后水样检测其“总氮”含量和氨氮含量,多次的实验结果显示,二者的总值最接近水样总氮的真实值。解决了煤制气黑水中总氮消解损失的问题。

The total nitrogen content in the black water of coal gasfication from the 150 kt polyol project was tested by the basic potassium persulfate ultraviolet spectrophotometry.Such tested result was lower than that of ammonia nitrogen,which was inconsistent with the theory.The direct reason is that ammonia nitrogen will be partially lost in the digestion process;the higher content of ammonia nitrogen in water samples,the higher loss in the digestion process,which leads to such inconsistency.In this regard,a solution scheme was put forward,that is,the black water samples were first distilled with ammonia nitrogen being removed,and then the total nitrogen and ammonia nitrogen contents in the distilled water were then tested.In this way,multiple test results showed that the total value of the two is closest to the real value of total nitrogen in water samples,which solves the issue of the digestion loss in the determination of total nitrogen in the black water from coal gasification.