How does Greywater Recycling work?

Firstly, reclaimed greywater is collected from hand wash basins, showers and baths and supplied into the greywater recycling system. The first stage of filtration within a greywater recycling system is designed to remove larger contaminants and debris through physical filtration via a mesh filter (filtered to 1000 microns or 1mm).

After this, reclaimed greywater enters a treatment tank where the water is oxygenated to provide a healthy environment for the biological treatment process to take place. Within the treatment tank, growth bodies allow healthy bacteria to grow as part of the purification process.

Reclaimed greywater is then filtered to microfiltration level through membrane filtration to remove any remaining bacteria and virus’. Membrane filtration technology filters the reclaimed greywater down to 0.2 microns.

Next, the treated greywater is transported a short distance to a clean water tank where the greywater is held for a short period until a demand for water is detected from the control panel.

During periods of low greywater supplies, an automatic mains water top ensures a constant water supply for points use. Finally, the recycled greywater is then boosted to toilets, irrigation systems, vehicle wash plants and other non-potable outlets via a booster set.

Greywater recycling systems

Installation considerations for Greywater Recycling

The size and cost of a Greywater Recycling System are highly dependent. Greywater Recycling Systems are sized by a specialist, like Stormsaver, based on a number of factors, including demand, building occupancy, collection potential, and greywater treatment processing yield. The sizing process will occur during the early stages of the building specification prior to construction commencing.

Greywater Recycling Systems are easiest to install in during the construction process. Whilst retrofitting a greywater recycling system to an existing building is much harder than in a newly constructed building, retrofitting a system is not impossible. It is recommended that a specialist like Stormsaver is consulted on the retrofit project at the early stage.

Once installed, greywater recycling systems can meet between 30-50% of the total water demand within the building if the system is sized correctly.

Maintenance considerations for Greywater Recycling

Once installed, Greywater Recycling Systems should receive a regular service by a specialist, like Stormsaver, every six months. The treatment tank of a greywater recycling system should also receive a regular tank clean every couple of years to remove the build up of natural sediment which occurs over time.

During routine maintenance, it is recommended to use a chemical cleaning solution to remove bio film inside the membrane station and associated pipework to ensure the highest levels of water quality. Some Greywater Recycling Systems, including the Stormsaver system, will have this functionality built in as part of an automatic backwashing feature. Greywater recycling systems which are not supplied with this functionality should receive manual chemical treatment on an occasional basis to remove biofilm build up.

Greywater Recycling Systems use real-time data to alert facility managers to any required remedial works. Systems are also often equipped with water level monitoring equipment and water saving data for preventative issues to be dealt with swiftly by a specialist. Greywater Recycling Systems are often connected to a central building management system which monitors all systems within a the building. This is usually managed by a facility manager. The Stormsaver Greywater System can be monitored remotely through an application on a smart phone, tablet, or desktop PC.

Greywater Recycling Systems should always be maintained by a specialist, like Stormsaver, who have extensive experience of water reuse systems. Regular maintenance providers will have limited knowledge of greywater recycling systems.

Learn more about Greywater Recycling System Maintenance here.

maintenance services

The benefits of Greywater Recycling

Greywater Recycling offers many benefits for businesses and commercial properties.

Greywater Recycling Systems can dramatically reduce mains water consumption by providing an alternative water supply. A reduction in water consumption through greywater recycling can also lead to significant financial savings on water bills. The Greywater Recycling System will have a payback period where the costs of installation are offset by savings on water bills. Although the payback period can differ from system to system, payback on a typical greywater system is usually between 4-7 years after installation.

Greywater Recycling offers many benefits for the environment by reducing the volume of water entering the existing drainage network. Diverting the substantial volume of greywater away from sewers means that the likelihood of a combined sewer overflow into rivers and seas is reduced. Greywater Recycling also protects potable water supplies during periods of droughts, allowing water companies to reserve potable water supplies for critical tasks, including drinking, food preparation and sanitation.

Installing a greywater recycling system can positively impact the environmental credentials of a business. Commercial properties who opt to install a greywater recycling system can gain up to five points in the industry recognised BREEAM scheme and count towards LEED building standards.


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