Different from conventional settling tanks, the BIOWORKS® clarifier is an integrated solution. The clarifier structure is located right at the end of the activated sludge basin and is separated from that by a common wall (1). The clarifier structure is of a rectangular geometry, with a length to width ratio of around 4:1. The activated sludge/water mixture streams through openings (2) in the common wall into the clarifier. Activated sludge will settle at the bottom of the clarifier and is sucked from the bottom (3) and pumped back to the inlet as return sludge (4), by a moving sucking scraper bridge (5) which moves alongside the clarifier back and forth. The clear water at the top of the water body water inside the clarifier passes the effluent openings (6) which are aligned at the opposite wall of the influent.
The number and location of the openings ensure that there is very slow and calm current in the clarifier. This avoids any potential stirrup of sludge in the settling zone. Our design eliminates the need for interconnecting pipes between activated sludge basin and clarifier.
In comparison to conventional circular settlers, the BIOWORKS® clarifier shows the following advantages:
- No hydraulic disturbance of the influent zone, as the inflowing water has very low velocity, due to the large inflow area at the common wall
- Much more economic use of the available land
- Elimination of interconnecting pipes and return sludge pump stations
- Simpler civil construction than circular clarifiers, particular with large diameters
BIOWORKS® clarifiers have been built for capacities up to 2.200 m3/h (as single unit)