Septic tank made by rotomoled polyethylene for treatment of mixed wastewater (gray and black) coming from domestic or equatable sewer designed for 4 up to 50 population equivalents in different configurations: single-chamber, double or three chambers septic tanks.


The septic tanks are primary treatments for wastewater from houses used as pre-treatment upstream input into sewer or upstream of a small sewage treatment plant.




The series of SEPTIC BLACK line is made by a polyethylene tank, in two different shapes depending on the size: vertical cylindrical, for small users, and horizontal cylindrical for higher flow rate. The septic tank is equipped with inspection covers DN 600 for cleaning and maintenance.
The septic tank is an ideal solution for the treatment of wastewater discharged from residential houses, small residential areas in general and commercial consumers. SEPTIC BLACK line is used to clarify civli domestic wastewater or similar, containing both black water from toilets that gray water from showers, sinks and kitchens. It’s not permitted to discharged water contaminated by mineral oils and hydrocarbons.


Technical Specifications

Septic tanks belonging to the SEPTIC tank BLACK series are manufactured with specific ribs to withstand stresses due landfill installation.
The series of septic tanks BLACK are engeneered in relation to the population equivalent (PE).
The septic tank allows the flotation of the lighter components of the wastewater (such as foams and fats) and the sedimentation of the heavier material (sludge and coarse materials). In the bottom zone the anaerobic digestion takes place decomposing part of the organic substance of the settled sludge.
The septic tank SEPTIC BLACK is available in three versions: single, double or three chambers in order to satisfy the requests by the authority.
The following table identifies possible configurations of the various models.
The connection between the different chambers is made by pipes or holes in the baffle realized at a correct distance between the surface and the bottom of the tank so as to avoid disturbing of the settlement processes (floating or settling).

The single-chamber septic tank is a pretreatment plant consisting of a single volume of calm that has the advantage of being very simple and with a very low risk of occlusion.
The two-chamber septic tank has two compartments of the same volume useful to improve pollutants removal.
The threee-chamber septic tank has three compartments of which the first (in which the most contaminated wastewater pass through) is twice then the next two, with the typical relationship between volumes of ½ ¼ ¼.

The Septic BLACK is tested to be installed at a depth up to 600 mm or 1200 mm depending on the tank version; in this case the tank can be equipped with an appropriate extension (available as accessory).

Every septic tank need connections to the vent column to avoid odours problems.

Sizes and features

The following sizes and features refer to the technical drawings reported below.

Septic Tanks SEPTIC BLACK single-chamber vertical cylindrical

SEPTIC BLACK M1000M11100013010080.075.0100
SEPTIC BLACK M1600M111600130150127.5122.5125
SEPTIC BLACK M2200M112200130200177.5172.5125

Septic Tanks SEPTIC BLACK horizontal cylindrical single-chamber

SEPTIC BLACK M4600M114600172250172146141160
SEPTIC BLACK M6600M116600172350172146141160
SEPTIC BLACK M7800M117800172400172146141160
SEPTIC BLACK M8500M118500172450172146141160
SEPTIC BLACK M10000M1110000172500172146141160
SEPTIC BLACK M11000M1111000172550172142137200
SEPTIC BLACK M13000M1113000172650172145140200

Septic Tanks SEPTIC BLACK horizontal cylindrical dual chamber

SEPTIC BLACK B4600B114600172250172146141160
SEPTIC BLACK B6600B116600172350172146141160
SEPTIC BLACK B7800B117800172400172146141160
SEPTIC BLACK B8500B118500172450172146141160
SEPTIC BLACK B10000B1110000172500172146141160
SEPTIC BLACK B13000B1113000172650172149144160

Septic Tanks SEPTIC BLACK horizontal cylindrical three chambers

SEPTIC BLACK T4600T114600172250172146141160
SEPTIC BLACK T6600T116600172350172146141160
SEPTIC BLACK T7800T117800172400172146141160
SEPTIC BLACK T8500T118500172450172146141160
SEPTIC BLACK T10000T1110000172500172146141160
SEPTIC BLACK T13000T1113000172650172149144160

NOTE: sizes can be changed without notice.
The letters in figures and table have the meanings set out below:

PE – population equivalent
T – solution type (M – single chamber, B – double chambers; T – three chambers)
U – number of units composing the product.
V – nominal volume
D – diameter (vertical cylindrical tank)
B – total width (horizontal cylindrical tank)
L – total length ((horizontal cylindrical tank)
H – total height (extension excluded)
H1 – inlet pipe height
H2 – outlet pipe height
DN – nominal pipes diameter

Smaller or with different shape septics are available in SEPTIC ORANGE. In case of special transportation needs, excavation requirement etc., AZU Water can provide a customised solution for the specific problem.

The SEPTIC BLACK is supplied with 600 mm diameter lid (standard version) or with telescopic extension with seal and polyethylene manhole with pedestrian lid manufactured and tested according to requirements of the latest international standard ISO 15398:2012 (BLACK accessory extension line).

For the installation you need to follow the steps in the procedure BLACK line use underground mode.
For a product tested and certified according to EN 12566-1 and CE is available the line of septic tanks SEPTIC ORANGE CE.
To lower users is available the range of septic tanks SEPTIC ORANGEline.

For further information and tailor made solutions, please contact technical office.



AZU Water ensures that domestic sewage or similar (black and gray water) treated by the SEPTIC tank ORANGE can be delivered into the public sewer.

AZU Water is available to develop solutions tailored to particular customer needs.