Automatic control system and method for condensate polishing mixed bed

Abstract

The invention discloses an automatic control system and method for a condensate polishing mixed bed and relates to the technical field of condensate polishing. The system comprises a mixed bed, a PLC,online conductivity meters, electric valves, an online hydrogen conductivity meter, an online sodium meter, an online chlorine meter and an online silicon meter, wherein outlet pipelines of a mixed bed A, a mixed bed B and a mixed bed C are respectively provided with an online conductivity meter and an electric valve, and the online hydrogen conductivity meter, the online sodium meter, the onlinechlorine meter and the online silicon meter are arranged on a main pipeline of a mixed bed; when the measured value of any one of the online hydrogen conductivity meter, the online sodium meter, theonline chlorine meter and the online silicon meter exceeds the control standard, the PLC closes the electric valve of the mixed bed with the maximal water outlet conductivity in the two mixed beds according to the measured values of the mixed bed A outlet online conductivity meter and the mixed bed B outlet online conductivity meter, and synchronously starts the standby mixed bed C to ensure thatthe water quality index of the mixed bed outlet main pipe is controlled within a qualified range, thereby realizing automatic control of condensate polishing of the mixed bed.

Description

technical field [0001] The invention relates to a condensate polishing treatment system in a power plant, in particular to a mixed-bed automatic control system and method for condensate polishing treatment. Background technique [0002] In the fully volatile feed water treatment process, in order to reduce the corrosion of thermal equipment and pipelines, the power plant usually adds ammonia water to the feed water to increase the pH value of the water vapor. The main purpose of the mixed bed is to remove various anions and cations in the condensed water. According to the standard of GB / T 12145 "Water Vapor Quality of Thermal Power Generation Units and Steam Power Equipment", the condensed water of supercritical and above units is finely treated in the mixed bed. The control standard after desalination is shown in Table 1: [0003] Table 1 GB / T 12145-2016 Water Quality Control Standards for Condensed Water After Fine Treatment and Mixed Bed Desalination [0004] [0005...

AI Technical Summary

Problems solved by technology

Since the main cation in condensed water is NH 4 + , which is exchanged for H after passing through the hydrogen-type mixed bed + , it is necessary to add ammonia water to the feed water again to increase the pH value of the water vapor. This repeated cycle not only increases the amount of ammonia water, but also shortens the water production cycle of the mixed bed (about 5 to 7 days). The mixed bed is frequently regenerated and the operating cost is high.

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