| 摘要 |
<p>Corrosion of effluent gas ducts in glass melting installations is suppressed by uniformly introducing into the aggressive effluent gases a finely pulverised cpd., pref. an oxide or hydroxide of Mg,Ca,Na or K. The powder (5-10 mu, pref. 10 mu) is injected into the gases in an amt. of 1-10 mg.equiv/Nm3 (pref. 4-8 mg. equiv./Nm3). Corrosive sulphuric vapours and particles of low-melting pyrosulphates or bisulphate of Na,K, and also their carbonates, sulphates, etc. contained in effluent gases from glass-melting installations, react with each other when the temp. of the gas phase drops below 460 degrees C forming low-melting substances corroding the installations and forming deposits reducing the heat transfer rate. Iron is attacked by the pyrosulphates and bisulphates of Na and K with formation of FeSO4. The injection of the oxides or hydroxides of alkali(ne earth) metals neutralises the acid components of the gas effluents; high-melting neutral sulphates are formed; corrosion is prevented; deposn. of dust is reduced because the particles of the high-melting sulphates are not tacky of temps. below 460 degrees C.</p> |
