Plants cleaning the way to a greener future?

'Living Machines' processing cosmetic waste water from Body Shop products.

 Plants are taking us back to our roots and helping to prove that the ecological way is a functional option, which saves energy and water. Evidence of this can be seen at Watersmead in Littlehampton where COSI manufacture some products for the Body Shop. Here, a 'Living Machine' processes waste materials naturally.

Plants working hard to help us

Plants can bring positive benefits to our lifestyles now and in the future. Processing waste matter, which is the function of a Living Machine, is only one area where plants can help, but it is an important one as it helps reduce the impact on our environment and prepares water for recycling.

Microbes living in the root systems of plants extract the chemicals from the effluent and use it to feed the plant's roots. In this way, waste matter is processed and cleaned naturally. The cleaned water, known as grey water, can then be used to water plants or flush toilets.

Waste from manufacturing

At the Watersmead cosmetic manufacturing plant in Littlehampton, the grey water from the Living Machine, installed to recycle commercial wastewater from the manufacture of The Body Shop products, is fed to the sewers.

The Living Machine at Watersmead is believed to be the first installation of its kind by a cosmetics company anywhere in the world. It was established in 1991 to process commercial waste used in the manufacture of the cosmetics.

How it works

The Watersmead Living Machine was especially adapted to process The Body Shop wastewater materials. The eco-system which processes the waste is contained in two identical parallel 'trains' of eight tanks in an insulated greenhouse. The effluent takes up to five days to pass through the system.

Before it enters the eco-system, the effluent enters a filtration tank, which removes particles and oils. Once in the system, the waste is split between the two trains for processing.

The first two tanks in the trains contain natural aquatic bacteria in vast numbers which slowly break down the organic pollutants using the carbon freed in the process to reproduce and increase their own bio-mass.

When the effluent enters the third tank, it is clean enough to allow the growth of some hardy species of aquatic plants. It is the micro-organisms that live in the root zones of these plants, which process the pollutants in this tank.

By the fifth tank, the water is clean enough to support five or six plant species, which continue the cleaning process through the micro-organisms in their root zones.

Four days later...

After approximately four days in the system, the waste reaches the last stage in the treatment process. By now, almost all of the dissolved organic pollutants have been broken down. Even at this stage, the waste is still cloudy with bacterial matter but now, the particles settle at the bottom of a small clarification tank. Bacterial sludge is removed automatically once an hour; half is recycled into the first tank to re-seed the system, and half is returned to the ultra-filtration system for processing.

The water is now suitable for discharge but before it leaves the Living Machine it must undergo a further half-day biological filtration in a special tank known as an Ecological Fluidised Bed. Here it is rapidly re-circulated through a column of recycled blast-furnace slag, a perfect habitat for bacterial slimes, algae, worms, snails and waterfleas which consume any of the remaining fine particles of bacterial 'floc'.

When the waste is finally discharged into the sewer, it contains less than ¼ of 1% of its original pollutants and less than 1% of its original detergent content.

Back to our roots

With growing concern from various well-respected bodies about the speed with which we are devouring natural resources, it is little wonder that we are returning to a reliance on the natural environment. Grey water recycling and Living Machines follow the trend to care for the earth and extend its natural life support systems.

Alex Walker of international company, Living Technologies who are responsible for several Living Machines in the UK commented, "Although we are some way behind our Continental neighbours and the USA, awareness for green issues is rising, particularly in the private sector."

As more and more businesses take heed and look to natural ways to improve their working environments and waste management, so plants will play a big part in shaping this new future for buildings and not just in Living Machines. Planted interiors will help improve humidity levels and noise absorption, reduce the symptoms of minor ailments and by implication, absenteeism, reduce stress levels thereby increasing productivity.

The latest Living Machine to be installed is at Earth Works in Doncaster. Other Living Machines can be found at:

The Watersmead site of COSI in Littlehampton - by prior arrangement

The Findhorn Eco Village in Scotland

National Botanic Gardens in Wales