1.The heat load of the moderator cell and liquid hydrogen due to nuclear heating is removed by the cold helium produced by the helium refrigeration system. The reverse Brayton cycle with liquid nitrogen pre-cooling is used in the helium refrigeration system.
2.as for the second biological contact oxidation pond, the optimal HRT and air/water ration were 2.64h(its ALR 0.78 kg/m3d) and 6 respectfully, the nitrifying effect was better as effluent D0=5~6mg/l.
