MICROWAVE FOAMING OF FOAM POLYSTYRENE GRANULES Russian patent published in 2012 - IPC B29B9/00 C08J9/16 

FIELD: process engineering.

SUBSTANCE: invention relates to foaming foam polystyrene granules containing pentane and isopentane and may be used in construction, production consumable patterns and moulding of articles and packages. Besides it may be used for both premary foaming and additional foaming of granules after primary foaming. Proposed method comprises proportioning initial granules, foaming them by steam treatment in foaming chamber, drying in drying chamber, cooling in cooling chamber, and storing foamed, dried and cooled granules in bins. Foaming is performed in microwave field in vertical waveguide chamber during steam treatment. Steam is generated in entire volume between loaded granules due to evaporation in microwave irradiation of water kept in microwave chamber in two sources, limited and recoverable sources. Limited source is made up of water film applied on granules in loading to envelop every granule. Recoverable source consists of steam generator working body saturated with water made up of porous deliquescent material arranged in waveguide chamber zone with maximum intensity of microwave radiation electric field.

EFFECT: no external steam source, lower residual moisture content, smaller overall dimensions.

4 cl, 1 dwg