Tertiary settlement is the final stage of the treatment process that is used to further purify the discharge effluent, to settle the biomass and in some cases return activated sludge to the secondary treatment stage. At Pollution Control we can provide a range of tertiary settlement solutions to suit each individual project, these can include clarifiers, conical settlement tanks and UV disinfection. Further filtration can be put in place after our tertiary settlement systems to purify the discharge effluent even further such as sand filters or reed beds. When combined with our primary settlement and Eco-SAF treatment systems our tertiary settlement systems form part of a complete system to suit all your water treatment needs.
Clarifier tanks are used to remove fine particles from effluent; they are usually square in shape with angled outer walls. They work by gravity combined with the angle of the walls of the tank. The effluent enters the tank; any particles in the effluent come into contact with the angled wall and slide down to the base of the tank which builds up as sludge. The effluent then flows over a weir and out of the tank to discharge. Sludge which builds up can be removed periodically or used as activated sludge in the Eco-SAF stage of the process.
Conical Settlement Tanks
Conical settlement tanks are similar to clarifier tanks but are round in shape, they work on the same principle of gravity and the angle of the outer wall.
Lamella Clarifiers work on the same principle as clarifiers and conical settlement tanks, the difference between them is that a lamella clarifier uses a series of inclined plates to increase the surface area of contact for the particles in the effluent. This means the efficiency of the clarifier is increased and the footprint is reduced, the Pollution Control range of lamella clarifiers is designed with a relatively small footprint. Our lamella clarifiers can be supplied in various footprint configurations so that they can be installed within existing plant.
UV Disinfection units can be installed between the tertiary settlement system and outfall point of the system. A UV Disinfection unit utilizes intense ultra-violet light to help purify the effluent; the effluent enters one end of the UV unit and passes the UV lights which disinfect the effluent before final discharge.
Sand Filters/Reed Beds
Sand Filters or Reed Beds can be installed as a final stage of the treatment process. The final effluent from our treatment systems is piped through a series of sand beds or reed beds, as the effluent moves through these beds it is purified to a high standard.