Automatic air supply type full-protection accurate oxygenation device for power plants and accurate oxygenation method

Abstract

The invention relates to an automatic air supply type full-protection accurate oxygenation device for power plants and an accurate oxygenation method. The air provided by a fan is adopted as oxygen source for oxygenation, the pressure of the compressed air is increased to a needed pressure level by a booster pump, i.e., the pressure of the compressed air is higher than the pressure of an oxygenation point, and thereby the requirement of oxygenation for automatically supplying the air to a drainage system, a water supply system and a condensate system and fully protecting a water vapor system is met. A PLC (Programmable Logic Controller) control cabinet roughly adjusts flow control valves according to flows of water samples (drained water, supplied water and condensate) and dissolved oxygenconcentration values of the water samples to be controlled, and then carries out fine adjustment according to actual measurement signals of water sample dissolved oxygen meters and the dissolved oxygen concentration values of the water samples to be controlled. Because the working medium of the flow control valves is normal-pressure air, the adjustment of the opening degrees of the flow control valves is also carried out under a normal-pressure working condition, consequently, the air flow control process is not affected by air compressibility, and accurate oxygenation control is realized.

Description

technical field [0001] The invention relates to the technical field of corrosion protection for thermal equipment in a power plant, in particular to an automatic gas supply type full-protection precise oxygenation device and an oxygenation method for a power plant. Background technique [0002] In order to prevent the flow-accelerated corrosion of the water supply system and the high-pressure drainage system and a series of adverse effects on the operation of the unit, it is obvious that the super (super) critical unit adopts the oxygen addition treatment technology. However, due to concerns about scale problems in superheaters and reheaters, there are still many super (super) critical units in China that do not use oxygen addition treatment. [0003] The full-protection oxygenation treatment technology refers to the addition of oxygen to the condensate water, feed water, and high-pressure hydrophobic systems. Maintain the dissolved oxygen concentration to meet the passivat...

AI Technical Summary

Problems solved by technology

The oxygenation method of the traditional oxygenation device is to use the pressure difference between the gas cylinder and the oxygenation point as the power of oxygenation, and adjust the amount of oxygenation under the condition of the gas supply pressure. Due to the compressibility of the gas, the flow rate of oxygenation is small, Oxygenation pressure is high, and the accuracy of oxygenation control is very poor. On the one hand, it increases the frequent adjustment workload of operation and maintenance personnel. On the other hand, the excess oxygen in the water supply enters the steam system, which increases the risk of promoting the concentrated peeling of the steam side scale, which is not conducive to Safe and economical operation of the unit

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