다양한 공정 단계에서 질산 생산을 최적화하기 위한 인라인 농도 측정

Nitric acid synthesis

Nitric acid has been technically produced by the Ostwald process since 1908. This involves the catalytic oxidation of ammonia. The mixture of ammonia and air is passed rapidly through hot platinum-rhodium nets (catalyst) which are located in the contact furnace. This produces nitrogen monoxide at 800 °C, which is then cooled back down to below 50 °C. In the oxidation tower, it oxidizes with excess oxygen to form nitrogen dioxide and then reacts with water in an absorption tower to form around 60 % nitric acid. Nitric acid can be concentrated up to 68 % by distillation, which corresponds to the azeotrope with a maximum boiling point (122 °C). Higher concentrations up to
90 % can be achieved by dehydration with magnesium nitrate Mg(NO3)2. With the density sensor L-Dens 7400 and the sound velocity sensor L-Sonic 5100, the different nitric acid concentrations in various process steps can be precisely measured and monitored. This ensures highest quality and optimizes production costs.