The dissolution rates of various types of magnetites were measured by an analytical spectrophotometric method allowing the determination of ferrous and ferric ions. Some testes were performed on magnetite electrodes galvanically coupled to steel electrodes. The influence of copper on the dissolution rates of magnetite was evaluated and the effect due to the presence of organic corrosion inhibitors was determined. A loop operating with boiler tubes was assembled in order to verify the possibility of monitoring the acid cleaning treatment by electrochemical measurements. Electrode potential-time curves, polarization curves and polarization resistance data were recorded. The calculated corrosion rates were compared to weigh-loss data obtained in the same experimental conditions. From the overall results some conclusions were reached both on the dissolution process of magnetite and on the monitoring of the acid cleaning treatment.
A contribution to the acid cleaning of boilers
TRABANELLI, Giordano;ZUCCHI, Fabrizio;FRIGNANI, Alessandro;ZUCCHINI, Massimo;
1979
Abstract
The dissolution rates of various types of magnetites were measured by an analytical spectrophotometric method allowing the determination of ferrous and ferric ions. Some testes were performed on magnetite electrodes galvanically coupled to steel electrodes. The influence of copper on the dissolution rates of magnetite was evaluated and the effect due to the presence of organic corrosion inhibitors was determined. A loop operating with boiler tubes was assembled in order to verify the possibility of monitoring the acid cleaning treatment by electrochemical measurements. Electrode potential-time curves, polarization curves and polarization resistance data were recorded. The calculated corrosion rates were compared to weigh-loss data obtained in the same experimental conditions. From the overall results some conclusions were reached both on the dissolution process of magnetite and on the monitoring of the acid cleaning treatment.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
