Septic tanks

Info

Boralit offers a range of products in polyethylene. Within this range, there are also septic tanks.

The classic feces tank only receives wastewater from the toilet (the so-called black water). The tank for all domestic wastewater receives all wastewater from the house, i.e. the black (toilet) water as well as the grey water.

Quite often only a classic feces tank (black water) is installed, although a tank for all domestic wastewater would certainly be preferred. The ideal type is the tank for all domestic wastewater. The wastewater received by this tank is much more homogeneous allowing the tank to function much better. In this case, the volume of the tank should be larger.

No rainwater should be allowed to enter the septic tank because this would render it useless.

The systems are easy to install by the limited weight and the tanks are guaranteed watertight.

On the septic tanks, there is a warranty label of 50 years on the housing against all perceptible production errors. The placement instructions have to be strictly applied. On the components, there is a warranty of 2 years.

Operation

A septic tank essentially liquefies the solids in sewage water. In this tank the solid biological wastes are either liquefied or converted into small particles. Some waste is dissolved into the liquid and the biological waste is consumed by anaerobic bacteria living in the tank. These anaerobic bacteria (living without oxygen) feed on the waste and convert it into gasses, small suspended solids and sludge.

The gasses dissipate through the ventilation shafts. The remaining solid particles (sludge) sink to the bottom of the tank (that is why a septic tank has to be pumped out from time to time). The smaller suspended particles are washed out to the sewer or to the water treatment system. The lighter particles float to the surface and form a "scum" layer. This scum layer cuts off the underlying liquid from the air, so less smell is formed and the bacteria can do their job more effectively.

A septic tank must be large enough to allow the raw sewage sufficient time to dissolve and be digested by the bacteria. This takes at least 5 days of retention time. A septic tank must be constructed with a baffle so the outflow begins well below the liquid surface. That way, if there is more inflow than normal, the incoming liquids cannot flow directly out of the tank without having allowed the bacteria to do their job. A similarly baffled inflow prevents the scum layer, that seals out the air, from being destroyed . To ensure effective performance, no rainwater should be allowed to enter the septic tank.

Advantages

Thanks to its limited weight even homeowners and handyman can install our products.
Because dirt does not stick to polyethylene, the tank can be easily and quickly cleaned without having to enter the tank.
Guaranteed watertight
Plant roots can not penetrate PE
Corrosion-resistant
100% recyclable
50 year warranty (under conditions)

All these advantages add up to a longer trouble-free service life.

Product range

Septic tanks to be place in consolidated sand (Round) Volume: 1.000, 1.500, 2.000, 3.000, 5.000 litres

Septic tanks to be placed in consolidated sand (Rectangular) Volume: 1.000, 1.500, 2.000 litres

Septic tanks to be place in sand (Cylindrical, standing up) Volume: 1.100, 1.600 litres

Septic tanks to be placed in sand (Cylindrical, laying down) Volume: 2.400, 3.300, 6.000 litres

Options

Boralit cover : Boralit plastic pedestrian cover (class A15)

Risers
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Instructions

Quite often only a classic feces tank (black water) is installed, although a tank for all domestic wastewater would certainly be preferred. The ideal type is the tank for all domestic wastewater. The wastewater received by this tank is much more homogeneous allowing the tank to function much better. In this case, the volume of the tank should be larger (see table below).

In the following table you will find the tank capacity as well as the corresponding number of users for Flanders and the Walloon provinces.
In Flanders one must allow for 300 litres per P.E. for a feces tank and 600 litres per P.E. for a tank for all domestic wastewater and for a tank with integrated filter. Also for the Walloon provinces this is 300 litres per P.E. for a feces tank up to 10 P.E., and from 10 I.E. 225 litres per P.E. For a tank for all domestic wastewater this would be 600 and 450 litres.

Volume	Flandres		Walloon
	Feces	All domestic water	Feces	All domestic wastewater
1.000 L	3	-	3	-
1.100 L	3	-	3	-
1.500 L	5	-	5	-
1.600 L	5	-	5	-
2.000 L	6	3	7	3
2.400 L CE	8	4	8	4
3.000 L	10	5	10	5
3.300 L CE	11	5	10	5
6.000 L CE	20	10	23	12

If there is no fixed number of permanent inhabitants (P.E.) please contact our technical service to calculate the correct number of P.E. This may be the case e.g. for schools, offices, hotels, campgrounds… You can contact us on the number 09 375 11 11.