A kind of compound alkalizing agent and its application

Abstract

The invention discloses a compound alkalization agent for the secondary circuit of a nuclear power plant, which is prepared from two-component or multi-component volatile alkaline substances. A type of basic A substance with a factor greater than 1 and a type of basic B substance with a vapor-liquid partition factor of less than 1 at 150-300°C, and the compound alkalizing agent meets the following conditions: During the first vapor-liquid distribution, the ratio K of the total molar concentration of the vapor-phase alkali to the total molar concentration of the liquid-phase alkali is 1.0 to 1.5. When the second vapor-liquid distribution occurs at 150-300°C, the total molar concentration of the vapor-phase alkali The ratio K to the total molar concentration of liquid-phase alkali is 0.5-1.0. The invention can avoid or reduce the environmental pollution caused by the use of single inorganic ammonia or organic amine, increase the operating burden of the mixed bed, high operating cost, high iron ion content in condensed water caused by too low pH, and the like.

Description

technical field [0001] The invention belongs to the field of water chemistry of nuclear power plants, and in particular relates to a compound alkalization agent and its application. Background technique [0002] At present, among the nuclear power units in service in my country, the secondary circuit of most nuclear power units adopts the all-volatile (AVT) water chemical treatment technology, that is, by adding ammonia (NH 3 ) and hydrazine (N 2 h 4 ) to control the pH value and oxygen content of the secondary loop system respectively. However, the vapor-liquid distribution factor of ammonia is relatively high. Most ammonia exists in the vapor phase at high temperature, and the ammonia content in the liquid phase is seriously low, which makes the secondary loop steam-water separation reheater system, high-pressure heater system, and deaerator system of nuclear power plants , low-pressure heater system, steam converter system, feedwater heater drainage recovery system, st...

AI Technical Summary

Problems solved by technology

[0011] Aiming at the technical disadvantages of using single inorganic ammonia or organic amine in the secondary circuit of active nuclear power plants, the present invention provides a composite alkalization agent, which rationally coordinates two or more different vapor-liquid distribution factors, thereby avoiding or Reduce the environmental pollution caused by using a single inorganic ammonia or organic amine, increase the operating burden of the mixed bed, high operating costs, high iron ion content in condensed water caused by too low pH, etc.

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