2种快速测定仪和实验室国标法测定沼液中氨氮浓度的对照分析

Comparison of Two Rapid Determination Instrument and Laboratorial National Standard Method to Determine Ammonia-nitrogen Concentration in Biogas Slurry

[目的]促进沼液商品化流通,实现田间地头快速测定沼液中的氨氮浓度。[方法]采用2种常见氨氮快速测定仪与实验室国标法中的纳氏试剂分光光度法(HJ 535—2009)进行了标准样品和沼液样品的氨氮浓度测定试验。[结果]2种快速测定仪中SD90715氨氮测定仪试验结果优于TFC实用型田间土壤化肥速测仪,测定氨氮标准样品精度较高,与样品真实值相关系数(r)达到0.997 2,与国标法测定结果相关系数(r)达到0.995 2;测定沼液中的氨氮与实验室国标法测定结果具有一致的偏向性,相关系数(r)达到0.981 0,且操作简单,速度快、无需配制试剂,适合非专业人士;给予校正系数0.798 0(r为0.978 4),可用于对沼液中的氨氮浓度进行快速定量。[结论]该研究可为沼液中氨氮的快速测定提供科学依据。

[ Objective]To promote the commercialization circulation of biogas slurry and realize the rapid determination of ammonia-nitrogen in biogas slurry in the fields. [ Method] Adopt two common rapid determination instruments and Nessler＇s reagent spectrophotometric method （HJ 535 -2009） of laboratorial national standard method to test ammonia-nitrogen in standard sample and biogas slurry sample. [Result] The results showed that the test results of SD90715 ammonia-nitrogen determinator from the two rapid determination instruments were better than that of the TFC utility-type soil fertilizer rapid determination instrument; the accuracy was higher when testing the ammonia-nitrogen in stand-ard sample; the correlation with the true value of the sample can reach to 0. 997 2 and the correlation with the determination result of the labo-ratorial national standard method can reach to 0. 995 2. The test results of the ammonia-nitrogen in biogas slurry were consistent biased with the results of the laboratorial national standard method and the correlation can reach to 0. 981 0. SD90715 ammonia-nitrogen determinator was fast and simple to operate and needs no reagent preparation, which was suitable for non-professionals. The correction coefficient was 0. 798 0 （r was 0. 978 4） , so it can be used for rapid quantitative determination of ammonia-nitrogen in biogas slurry. [ Conclusion ] This study can provide scientific basis for rapid determination of ammonia nitrogen in biogas slurry.