Which pipes need to be connected to the grease separator?
Grease separators have at least two and usually three pipes, which must be properly connected to the tank during installation:
- An inlet pipe (with additional venting if necessary)
- An outlet pipe
- Where applicable, a disposal pipe
The binding regulations applicable to pipe routing and surrounding drainage systems are explained in detail below.
Connecting the supply pipe
When connecting the inlet pipe, ensure that it is laid as a ventilation pipe above the roof and with a continuous downward slope of at least 2% (1:50). If the inlet pipe does not have a separately ventilated connection pipe over a horizontal distance of 10 metres, it must be fitted with an additional ventilation pipe as close to the separator as possible. If the inlet pipe is laid over a longer distance and/or through unheated rooms, the installation of thermal insulation and/or trace heating with a thermostat is recommended.
calming section
A settling section must be installed immediately upstream of the grease separator to prevent turbulence in the separation tank. The length of the settling section must be at least ten times the nominal size of the inlet pipe in millimetres – for an inlet pipe with a nominal size of DN 100, this means at least 1,000 mm. The transition from a vertical downpipe to the settling section must be carried out using two 45° pipe bends, which are connected to each other by an intermediate section at least 250 mm long.
Connecting the drain pipe
As with the inlet pipe, care must be taken when connecting the outlet pipe to ensure that it is laid with a continuous downward gradient. If the water level in the separator tank is below the backwater level, the outlet pipe must, in accordance with DIN EN 752-1, lead to a downstream lifting station that pumps the wastewater above the backwater level.
Further guidelines
Drainage points
All drainage points through which waste water is fed into the grease separator must be fitted with odour traps and, where necessary, removable sludge buckets.
disposal pipe
In addition to the inlet and outlet pipes, a disposal pipe must also be connected to grease separators with direct disposal.
Wastewater temperature
In some cases, measures may need to be taken to limit the temperature of the wastewater at the property boundary in accordance with regulatory requirements.
