PURPOSE: To absorb and remove formaldehyde and make it harmless by passing the exhaust gas containing formaldehyde from a thermosetting type adhesive agent producing plant in an aqeous caustic alkali solution.
CONSTITUTION: In the thermosetting type adhesive agent producing plant for urea resins, phenolic resins, etc., free formaldehyde is released during vacuuming of a storage tank 1 and reactor 2. If this exhaust gas containing formaldehyde is sent into a vapor-liquid contact unit 6 and is passed in an aqueous caustic alkali solution such as of caustic potash or caustic soda, the formaldehyde is reacted and absorbed by the caustic alkali. In this way, the formaldehyde is effectively absorbed and removed and is made harmless, whereby the atmospheric pollution is prevented.
MATSUOKA NORIMICHI
NAKANISHI TSUNEO
| JPS50140363A | 1975-11-11 |