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Recycle greywater

Select an area of application
›› Domestic
›› Commercial
›› Get to know how it works
›› Get to know how it works
Coarse filter
Greywater collection tank
Greywater filtration tank
Membrane filter
Process water tank
Backwash
Control system
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Coarse filtration - The grey water collected separately is first freed of its undissolved water constituents, such as hair and textile fluff.
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Aerobic biological cleaning - All organic pollutants, such as shower gel and soap, are biodegraded by special waste water bacteria in the aerated grey water tank.
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Sedimentation - The aeration in the filtration tank is controlled so that particles and suspended matter settle before ultrafiltration.
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Ultrafiltration - The grey water is forced through the membrane filter in a controlled manner and cleaned. The backwashing of the GWtec® filter depends on the degree of soiling.
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Storage of process water - The purified grey water can be stored for the long term and reused without hesitation.
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Backwash - The membrane filter is then backwashed with process water, which is not lost in the process. The control system is fully automatic and regulates the cleaning process depending on the level of soiling.
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Fully automatic control unit - a fully automatic control system has been developed to regulate and monitor all operating processes. The display is shown on a high-resolution ten-inch touchscreen. The tried-and-tested DehoustCONNECT web interface enables real-time access to all system processes such as treatment performance or filter status. Access is via smartphone, tablet and PC.
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Recycle Greywater for a Greener Future

Mechanical-biological filtration for high-quality process water for secondary use instead of discharging slightly contaminated water from showers or hand washing directly into the wastewater system.

With our DEHOUST GWtec®, we rely on an effective combination of wastewater bacteria and ultrafiltration for this purpose. This saves valuable water. The costs for drinking water and waste water are reduced.

What is grey water?

Grey water is wastewater that comes from showers, bathtubs and hand basins. In contrast to black water, this is free of faeces and only slightly contaminated. Greywater can be treated and reused as process water - for flushing toilets, for washing machines or for watering the garden. This significantly reduces drinking water consumption and promotes sustainability.

High water quality

The process water is hygienically safe, clear, free of suspended solids and odourless.

The membrane technology reliably retains particles with a physical pore width of just 38 nanometres, such as particles, germs or absorbed viruses. Biological purification keeps the nutrient content of the water low. Thanks to ultrafiltration, there is hardly any detectable residual biomass. This means that the grey water treated as process water can be stored for the long term.
The water quality complies with the European standard EN 16941-2

How does the system work?

For grey water systems, we rely on mechanical-biological filtration - completely without chemicals. The first step is coarse filtration. Undissolved water constituents such as hair or textile fluff are removed from the grey water. Organic contaminants such as shower gel or soap are then aerobically and biologically degraded by wastewater bacteria. The aeration in the tank is controlled, particles and suspended matter settle to the bottom as sediment.

During ultrafiltration, the membrane filter cleans the pre-treated grey water. The membrane filter is then backwashed with process water, which is not lost in the process. The control system is fully automatic and regulates the cleaning process depending on the level of contamination.

The cleaned grey water (process water) is stored until it is needed. If there is no process water in the storage tank, drinking water is replenished via an integrated drinking water separation station in accordance with EN 1717. The systems are energy-efficient with a consumption of 0.3 to 0.5 kWh/m3 of treated grey water.

Integrated heat recovery

Maximize energy efficiency with our optional heat recovery system GWtec® WRG. Using a combination of a heat exchanger and a heat pump, the system captures heat from treated water and feeds it back into your hot water system. This innovation lowers energy bills and minimizes your carbon footprint.

Operation and maintenance

In principle, the systems are controlled via a control unit. A fully automatic control system has been developed here. The display is shown on a high-resolution four-inch touchscreen.

DehoustCONNECT was developed for the Dehoust ‘GWtec’ treatment systems. The tried-and-tested DehoustCONNECT web interface enables real-time access to all system processes such as treatment performance or filter status. Access is via smartphone, tablet and PC.

Online monitoring notifies users in good time about upcoming maintenance or deviations from the standard status. Basic maintenance is carried out after 10,000 operating hours. The membrane filter is replaced after one to two years, depending on requirements.

Always connected with the app

Thanks to the Dehoust Connect embedding, system operators can view the status of their systems at any time. All operating data is available at the click of a button.

Potential faults or malfunctions can be recognised at an early stage. This protects against downtime. The system settings of the various process water systems can be accessed via remote maintenance and adjusted if necessary. This ensures the safe and trouble-free operation of the systems.
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Grauwasser Aufbau
Grauwasser Aufbau

The advantages of grey water recycling

In addition to saving valuable drinking water through secondary use and continued high water quality, the installation of a grey water system offers further advantages. Thanks to the short amortisation period, customers save money through reduced drinking water costs and wastewater charges. Building owners and planners can achieve higher certification classes according to BREEAM, LEED or DGNB by installing the system, thereby increasing the value of their property. Many local authorities also promote the purchase of grey water recycling systems.

Interested?

You can use our planning tool to estimate the expected grey water production and process water requirements for your project. Based on your data, we will submit a proposal for your optimum grey water utilisation system.

>> to the planning tool