IMHOFF - Model Series Bio -Biological Septic Tanks
The treatment of sewage of civil origin by means of an "imhoff" type is very old and dates back to the last century, when the first septic tanks appeared. These in the past have found a great diffusion even on systems serving large communities; currently their use is limited to small settlements mainly rural or as pre-treatment to further purification stages such as percolator beds or biodisks.
These pits are cylindrical monobloc structures able to guarantee excellent stability for the loads; they are made with PRFV (Glass Reinforced Plastics) that ensures an almost unlimited duration of the products, a perfect impermeability, as well as lightness and manageability that reduce transport and installation costs.
In the "imhoff" tanks in which only the toilet drains are conveyed, there are two clearly separated zones: the upper sedimentation zone where the slurry releases most of the suspended sedimentable solids that will flow by gravity into the other compartment; the lower digestion zone in which the organic substances are attacked and then stabilized.
Normally there is a reduction of the organic load, expressed as BOD, of the order of 25-30%. The emptying of the lower sector must be carried out annually; to facilitate this operation in the tanks with utilities up to 20 inhabitants, sedimentation is extractable.
NALDI Ecologia, in order to guarantee a more efficient disinfection of the treated sewage, builds chlorination compartments and is at the complete disposal of its Customers for the realization of "imhoff" type baths, also made to measure.