Process for preparing paraformaldehyde

A process for the production of a powdery, free-flowing paraformaldehyde comprising:

• a. forming a particulate formaldehyde product by spraying a concentrated aqueous formaldehyde solution containing from about 75% to about 90% formaldehyde by weight into a spray chamber and contacting the formaldehyde spray with an inert cooling gas flowing through said chamber,
• b. removing said particulate product from said spray chamber, said particulate product being at a temperature of from above 40.degree. to about 60.degree. C. and passing said product into the first of a plurality of fluidized beds,
• c. simultaneously drying, curing, and concentrating said product in said first bed by fluidizing said product with an inert gas, said gas being at a temperature below the sticking point of said product,
• d. passing the concentrated product from said first bed into at least one other fluidized bed connected therewith and further increasing the concentration of paraformaldehyde in the particles of said product by fluidizing said particles with a separate stream of inert gas, said separate inert gas being at a temperature below the sticking point of the powder in said other fluidized bed and at a temperature greater than the temperature of the inert gas in said first bed, and
• e. recovering a dry, free-flowing particulate paraformaldehyde from the last bed of said plurality of fluidized beds.