Unmatched within the league of similar equipment, the purpose of the latest development of A.B.Clear biological wastewater treatment systems was to facilitate their use and to make the operation of wastewater treatment plants more stable.
The essence of the new technology is that after a preliminary thickening, the excess activated sludge produced during plant operation is collected in a so-called sludge dewatering unit, or sludge bag. This functions as a mechanical filter, where the solid, flaky content of the thickened sludgy water, i.e. the sludge is kept within the bag, while the liquid part is recirculated into the system.
This solution is advantageous with respect to the maintenance of the plant, as it eliminates the need to have the collection tank sucked 2-3 times a year, in the course of which large amounts of water is also lost, and either a suction truck or a sludge pump is required to have the excess sludge removed. Solid content collected in the sludge bag requires much less space and the bag can be easily emptied.
The bag simply has to be removed from the air-lift pump upstream of the sludge bag, disconnecting the bag together with the inlet pipe, then after loosening the clamp, the bag can be removed from the pipe. The contents can be emptied onto a compost pile, or as household waste.
Excess sludge, which has been properly composted through a year or a year and a half, no longer contains the pathogens, which were there before composting, making the material suitable for use in the garden along with other composts, for example for fertilization of vegetables. Garden compost containing excess sludge has a high nutrient content, thus it can be used as a valuable base material instead of becoming hazardous waste as a residual product of sewage water removal.
In terms of operation of the wastewater treatment plant, another advantage of this solution is that the amount of sludge is constant within the system, thus operation is more stable, than in case of other configurations, where after removal of the excess amount, there is a chance that either too much, or too little sludge is left behind in the tank.
