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How GDisk® Filters Work

Influent water filters through the GDisk® pile cloth, passes from the disk interior to the center tube, and out over an effluent weir.  As solids are captured within the pile, GDisk® automatically backwashes at a set water level or timed interval.  Solids are wasted via the patented GDisk® backwash manifold or tank bottom sludge collector.

Beacon’s Pile Cloth Disk Filter (GDisk®) is a highly efficient filtering device that can be effectively operated when the concentration of suspended solids becomes high or hydraulic loading rate increases, unlike conventional filtering devices, and with a low backwash rate.  Influent water filters by gravity through the proven GDisk® pile cloth, passes into a disk segment interior, through a connection port to the center tube, into the effluent chamber, and over an effluent weir. 

During filtration, solids deposit on the outside surface of the cloth media, forming a mat, as clean filtrate flows through to the inside of the filter cloth.  GDisk® automatically backwashes at a set water level or timed interval without interrupting the filtration process.  As the solids build up on the cloth media surface, headloss increases the water level inside the tank. 

The backwash process uses a centrifugal or submersible pump to create a suction and remove the solids from the surface of the cloth media via a very efficient backwash manifold.  The drive motor and chain slowly rotate the disk and the pump pulls a vacuum on the backwash manifolds located on each disk side.  Filtered water from the disk interior straightens and fluctuates the cloth fibers via the patented primary and main manifold slots.  Once past the main slot, the pile is laid back down by the manifold.  The vast remainder of the disk media not being cleaned by a manifold continues to filter water.  Multiple disks are sequentially cleaned until the low water level is achieved.

Enhanced Backwash

  • The primary slot and main slot of the backwash manifold are divided by a partition
  • Pile threads undergo delayed straighten and fluctuation while going through the primary slot
  • The main slot straightens the pile threads rapidly, enhancing backwash efficiency
  • GDisk® dual slot arrangement minimizes backwash water volume versus legacy manifold designs

Filtering

Filtering Process
  • Water enters the tank, completely submerging the pile cloth media disks
  • By gravity, water passes through the GDisk® cloth media, into the disk interior, to the center tube, and over an effluent weir
  • Solids accumulate on and within the pile cloth media, enabling enhanced depth filtration, capturing smaller particles than the nominal filtration rating of the media

Backwash

Backwash Process
  • Backwash is initiated at a set water level or timed interval.  A level sensor detects the water level as solids are captured and pressure drop increases
  • Solids are backwashed from the pile cloth media via a patented backwash manifold on each disk side.  Filtered water from the disk interior straightens and fluctuates the cloth fibers via the patented primary and main manifold slots
  • Disks are cleaned in pairs—for larger units, multiple disk pairs are cleaned simultaneously.  Disks rotate slowly (±1 RPM), allow each disk segment to be cleaned efficiently
  • Backwash water volume is relatively low, typically 1 – 3% of forward flow
  • As a continuous filter, the vast remainder of the GDisk® media not being cleaned by a manifold continues to filter water during backwash

Solids Discharge

Desludge Process
  • GDisk® outside-in filtration process allows heaver solids to settle to the tank bottom and are kept off the media surface, increasing loading rates
  • Settled solids are wasted periodically through the sludge manifold by a GDisk® system pump