Specificity of analytical methods used to determine the concentration of formaldehyde in workroom air

Interferences from 17 commonly occurring organic compounds to the determination of formaldehyde have been studied. The tested methods were acetylacetone (colorimetric and fluorometric) chromotropic acid (with and without evaporation), MBTH, pararosaniline and 2,4-dinitrophenylhydratzine-HPLC methods.     

Control of H2S Emissions During Slag Quenching

An analysis of slag pit variables has been made and correlations obtained between pit dimensions, time interval between pours, and the slag temperature when the pit is filled and ready for quenching. Field trials have demonstrated the effect of temperature on the level of emission and how the level varies during the quench period. Quantitative information has been obtained to show the effects of slag filling rates, air cooling prior to quenching, and the influence of oxidizing agents added to the quench water. A significant reduction in H₂S emission level can be attained by proper application of these results.