Definition

Noun: A filter bed is a layer or bed of porous material, such as sand or gravel, through which a liquid (typically water) is passed to remove solid particles and impurities. It is a key component in water purification and sewage treatment systems.

Usage

A filter bed is used as a singular, countable noun. It refers to the physical structure or installation. * The water treatment plant uses a large filter bed of sand and anthracite. * Maintenance involves periodically cleaning the filter bed.

Examples

• The old filter bed needed to be replaced to improve water quality.
• Engineers designed a new filter bed with multiple layers of different media for more efficient filtration.

Advanced Usage

• In technical/engineering contexts: The term is used to describe specific designs, such as a or a , which differ in flow rate and biological activity.
• In passive constructions: Often used to describe the process, e.g., "The wastewater is treated by passing it through a filter bed."

Variants and Related Words

• Filtration bed: A less common but synonymous term.
• Filter media: Refers specifically to the material (sand, gravel, activated carbon) that fills the filter bed.
• Sand filter: A common type of filter bed using sand as the primary medium.

Synonyms

• Strainer bed
• Percolation bed
• Purification bed

Related Phrases

• To pass through a filter bed: Describes the action of filtration.
  • All drinking water must pass through a filter bed before entering the distribution system.
• Layer of a filter bed: Refers to a specific stratum within the bed.
  • The top layer of the filter bed catches the largest particles.

Noun

1. filter consisting of a layer of sand or gravel for filtering water