PROCESS FOR PURIFYING INDUSTRIAL GASES AND INDUSTRIAL FLUE GASES

摘要

In the purification of cyanide-containing gas wash water with formaldehyde the accurate dosage of formaldehyde constitutes a problem particularly in the case of intensely varying cyanide contents. By continuous potentiometric measurement in a secondary flow which is adjusted to a pH value of 7 to 10 while the pH value of the main flow remains unchanged the formaldehyde dosage can be reliably adapted to the cyanide contents at any given time.