FLOTATION; DIFFERENTIAL SEDIMENTATION (sedimentation in general B01D21/00; in combination with other separation of solids B03B; sink-float separation B03B5/28; detergents, soaps C11D)

Description

B03D covers flotation and differential sedimentation processes for separating solid materials based on their physical and chemical properties in liquid media. Flotation methods exploit differences in surface wettability and hydrophobicity to selectively separate mineral particles, while differential sedimentation separates solids by exploiting differences in settling rates under gravity or centrifugal forces. This subclass encompasses flotation equipment (cells, columns), reagent systems, and process control methods, as well as sedimentation and clarification devices used in mineral processing, wastewater treatment, and industrial separation applications. Related separations by magnetic or electrostatic means are classified elsewhere in B03.

Filing statistics

CPC subclass B03D recorded 9,906 patent applications worldwide between 2013 and 2023. Annual filings grew from 518 in 2013 to 1,012 in 2023 (+95%), peaking at 1,136 applications in 2018. The most active applicants in class B03 are CENTRAL SOUTH UNIVERSITY (405 applications), CHINA UNIVERSITY OF MINING AND TECHNOLOGY (310 applications) and KMUST (KUNMING UNIVERSITY OF SCIENCE AND TECHNOLOGY) (303 applications).

Source: EPO PATSTAT, worldwide filings