| In this paper,based on the analysis of the operating conditions and corrosion status of air-cooled condensers in some domestic units,the causes of the corrosion of direct air-cooled condensers are analyzed.The types of alkalizing agents used to control the corrosion of direct air-cooled condensers were developed and the experimental study was carried out to study the effect of corrosion control.The results show that improving the pH value of water vapor is one of the effective measures to curb the corrosion of carbon steel air-cooled condenser and reduce the iron content of condensed water by analyzing the operating data and corrosion situation of domestic and external direct air-cooling units.But the pH value will greatly shorten the water cycle of fine processing,part of the power plant using a high pH value of the mixed-bed mode of operation,but there are fine treatment of leakage of sodium ions and chloride ions,etc.,resulting in water supply related indicators Less than the standard value.Therefore,it is necessary to study an alkalizing agent that can control the operation of the air-cooled condenser and ensure the long-term operation of the fine treatment,which is used to solve this problem.The experimental results show that the effects of #1,#2,#3 and #4 alkalizing agents on the properties of the ion exchange resin were investigated by thermodynamics.Resin properties did not significantly affect the #5 alkalizing agent on the sun,anions have a slight impact.The results showed that #1,#2 and #3 alkalizing agents were lagging behind the time of ammonia leakage,and the effluent conductivity of the mixed bed was measured by monitoring the effluent conductivity of the mixed bed.Changes to prevent the alkalizing agent from leaking into the feedwater system,while the #4 and #5 alkalizing agents are close to the ammonia leak time point and are difficult to avoid leaking into the feedwater system in industrial applications.It was found that the corrosion resistance of #1,#2 and #3 alkalizing agents was tested by Tafel polarization method.It was found that the corrosion rate of #2 alkalizing agent was the highest among the three drugs.When the concentration reached 10 mg/L The corrosion rate of the two alkalizing agents is less than that of the other two alkalizing agents.The corrosion rate decreases with the concentration of 50mg/L,and the thermodynamics calculated at the two concentrations is 0.355mg/L and 1.776mg/L.The corrosion rate of the alkalizing agent is the lowest among the three agents.When the concentration reaches 15mg/L,the decrease rate of corrosion rate is slowed down.The concentration of thermodynamics is 1.515mg/L.#1 alkalizing agent when the concentration reached 30mg/L,the corrosion rate decreased trend,the corresponding thermodynamic theory calculated dosing concentration of 0.287mg/L.The results show that the pH value of the feed water is 9.20~9.40 and the mixed-bed is better than that of the pretreatment process.Before the operation extended for 4 days.The concentration of iron in the condensate is about 23% lower than that of the drug before the concentration of 1.0mg/kg in the steam is in the range of 0.5mg/kg~1.0mg/kg.The reasonable concentration of alkalizing agent in the interval of 0.3mg/kg~1.0mg/kg,to maintain the concentration of 0.3mg/kg steam,the condensate water content decreased by about 75% before the drug.Two kinds of Organic amine into the furnace will be decomposed into low molecular organic acids,so to ensure that the fine treatment of hydrogen-type operation,control the export of direct exposure of the sun bed is less than 0.3μs/cm. |
