Automatic and Semi-automatic Kjeldahl Nitrogen Analyzers adopts international Kjedahl method to add nitrogen to nitrogenous sample directly. Full intelligent software design can make experimenter finish the distillation of sample in minutes. It can automatically add quantitative required reagentand make intelligent inspections on various states. Distillation and condensation automatic cleaning system further improves measuring accuracy. Friendly interface of the instrument can display rich information, which makes users master its operation easily.