METHOD AND DEVICE FOR MAINTAINING CORROSION RESISTANCE OF STEEL CIRCULATING CIRCUIT CARRYING LEAD-CONTAINING COOLANT (ALTERNATIVES) Russian patent published in 2005 - IPC

FIELD: nuclear power engineering; power plants using lead-containing liquid-metal coolants.

SUBSTANCE: proposed method includes following operations. Coolant is pumped through circulating loop. Solid-phase oxidizing means is introduced in coolant and dissolved therein. Concentration of oxygen dissolved in coolant is maintained at level not lower than maximal permissible value found from formula including concentration of oxygen dissolved in coolant, maximal coolant temperature in circuit, oxygen concentration, coefficient of lead thermodynamic activity in coolant, and lead concentration therein. Solid-phase oxidizing means is held in coolant-permeable reactor pot and coolant is pumped through this pot. In the process oxygen concentration is measured by means of coolant concentration sensor and maintained at desired level equal to at least maximal permissible concentration by measuring coolant temperature in reactor pot, or oxygen concentration is measured by means of oxygen concentration sensor and maintained at desired level equal to at least maximal permissible oxygen concentration by measuring coolant flowrate in reactor pot, or pre-oxidized coolant is fed to inlet of reactor pot. Device of first design alternate implementing proposed method has direct-flow section in steel circulating circuit joint, ejector in direct-flow section, and reactor pot with oxidizing means in return line joint. Inlet and outlet parts of return line communicate, respectively, with inlet part of direct-flow section and with ejector contraction. Device of second design alternate has reactor pot with oxidizing means and adjustable heating system, as well as line for returning part of oxidized coolant from reactor pot outlet to its inlet. Reactor pot is open at ends and is vertically mounted in box communicating with circuit.

EFFECT: enhanced service life of steel circuit, eliminated slag deposition, enhanced operating efficiency due to high corrosion resistance.

15 cl, 8 dwg, 1 ex