Novel composite alkalizer and application thereof

Abstract

The invention discloses a novel composite alkalizer for a nuclear power station secondary circuit. The novel composite alkalizer is prepared by a dual-component or multi-component volatile alkalescence substance. The composite alkalizer comprises at least one of alkalescence category A substances with a gas-liquid distribution factor being greater than 1 at temperature of 150-300 DEG C and one of alkalescence category B substances with the gas-liquid distribution factor being less than 1 at the temperature of 150-300 DEG C, and the composite alkalizer can satisfy the following conditions: when first gas-liquid distribution is generated at the temperature of 150-300 DEG C, a ratio K of total mole concentration of vapor-phase alkali to total mole concentration of liquid-phase alkali is 1.0-1.5, when second gas-liquid distribution is generated at the temperature of 150-300 DEG C, and the ratio K of total mole concentration of vapor-phase alkali to total mole concentration of liquid-phase alkali is 0.5-1.0. According to the invention, the composite alkalizer can avoid or reduce the problems that due to usage of single inorganic ammonia or organic amine, environment pollution is generated, operation burden of a mixed bed is increased, operation cost is high, and iron ions content in condensed water is high due to excessively low pH value.

Description

technical field [0001] The invention belongs to the field of water chemistry of nuclear power plants, and in particular relates to a novel composite alkalizing 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 syste...

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 novel composite alkalizing agent, which rationally coordinates two or more different vapor-liquid distribution factors, thereby avoiding the Or reduce the environmental pollution caused by the use of 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.

Images