Filter apparatus

A filter apparatus of the type including a tank, a filter bed support in the tank supporting a bed of filter material above the bottom of the tank, carriage means mounted for movement along the tank in a carriage path, a plurality of partititions extending transverse to the carriage path and spaced apart therealong separating the bed into a plurality of open top filter cells above the filter bed support and defining a plurality of fluid receiving compartments below the filter bed support each individual to a respective one of the filter cells, influent means for supplying an influent to the tank above the bed, a plurality of filtrate ports spaced apart along a port locus paralleling said carriage path with each filtrate port communicating with a respective one of the fluid receiving compartments, a filtered water effluent launder extending along said port locus and communicating with said filtrate ports, carriage drive means for driving the carriage along the carriage path in a backwash run, travelling backwash means including a backwash head carried by said carriage means for movement along said port locus sequentially into communication with each of said filtrate ports, the backwash means including a collector hood carried by the carriage means for movement along a path adjacent the upper surface of the filter bed sequentially into overlying relation with the top of each filter cell when the backwash head is in communication with the filtrate port associated with that filter cell, the backwash means including waste water pump means connected to the collector hood for pumping waste water therefrom, means for operating the backwash means during the backwash run to supply backwash fluid through the backwash head to the filtrate ports and to deliver waste water from the collector hood to sequentially up-flow backwash the filter cells in a preselected sequence, cell scavenging means including a fluid intake head carried by the carriage means for movement along said port locus sequentially into juxtaposition with each of the filtrate ports, the fluid intake head being spaced from the backwash head in a direction opposite the direction of movement of the carriage means in said backwash run, and means for operating the cell scavenging means during the backwash run to draw fluid into the fluid intake head through the filtrate port juxtaposed thereto and down-flow scavenge the associated filter cell subsequent to backwashing of each filter cell.

A filter apparatus of the type including a tank, carriage means movable in a carriage path along the tank, a filter bed support supporting a bed of filter material above the bottom of the tank, a plurality of partitions extending transverse to the carriage path and spaced apart therealong defining a plurality of fluid receiving compartments below the filter bed support, influent means for supplying an influent to the tank above the bed, a plurality of filtrate ports spaced apart along a port locus paralleling said carriage path with each filtrate port communicating with a respective one of the fluid receiving compartments, a filtered fluid launder extending along said port locus and communicating with said filtrate ports, carriage drive means for driving the carriage means along the carriage path, travelling backwash means including a backwash head carried by the carriage means for movement along a path extending along said port locus sequentially into juxtaposition with each of said filtrate ports and a collector hood carried by the carriage means for movement along a path adjacent the upper surface of the bed sequentially into overlying relation with the top of each filter cell when the backwash head is in juxtaposition with the filtrate port associated with that filter cell, the backwash means including waste water pump means connected to the collector hood for pumping waste water from the hood, means for operating the backwash means to supply backwash fluid to the backwash head and to pump waste water from the hood for up-flow backwashing the filter cells during movement of the carriage means in either direction along said carriage path, cell scavenging means including first and second fluid intake heads mounted on the carriage means for movement therewith along a path extending along the port locus and at relatively opposite sides of the backwash head sequentially into juxtaposition with each of the filtrate ports, the first intake head leading the backwash head during movement of the carriage in a first direction along the carriage path and the second intake head leading the backwash head during movement of the carriage in a second direction along the carriage path, means for operating the cell scavenging means to draw fluid into at least the fluid intake head that trails the backwash head during movement along the tank to sequentially withdraw fluid from each filtrate port and down-flow scavenge the associated filter cell.