INVESTIGATION OF POSSIBLE LINE-LENGTH EFFECTS IN THE MEASUREMENT OF OXYGEN AND HYDROGEN IMPURITIES IN SODIUM

摘要

The response of on-line impurity meters to step changes in oxygen and hydrogen activities of flowing sodium were measured before and after the sodium had passed through 100 ft of Type 304 stainless steel tubing. Tests were conducted at sodium temperatures of 350, 450, and 565°Cwith electrochemical oxygen meters and at 450 and 565°C 'with diffusion-type hydrogen meters at sodium flow rates of 2.5 and 5 gpm. Both increasing and decreasing step changes in the activities of oxygen and hydrogen were introduced in separate experiments. The levels of these impurities were chosen to simulate those expected in an LMFBR. No adsorption-desorption effects on the walls of the 100 ft of tubing could be detected by the on-line meters. The uncertainty on the meter readings was ~4% for the oxygen meters and ~6% for the hydrogen meter. Thus, no loss of sampling accuracy would be encountered by locating the sampling or monitoring station 100 ft from the main sodium system of a liquid-metal-cooled fast breeder reactor.