Most people might think we will have to give up economic development if we are to save the environment. But not if you look at the example of Denmark, which last year achieved startling economic growth, consuming 7 percent more energy, while at the same time cutting its emissions by 13 percent. In today's report from the Nordic nation, we investigate the country's water recycling facilities.
( Rain but no rivers )
On a wet afternoon by a canal in Copenhagen, a jazz band entertains the tourists.
Keeping in step with Denmark's unpredictable weather is more difficult, as the clouds part and the sun comes out again. But despite the frequent showers the entire country does not have a significant river to speak of.
Even the canal that cuts through the city's colorful Nyhavn district contains seawater.
The flat landscape of Denmark, where the highest hill is only 180m tall, cannot hold water, so Copenhagen is forced to use seawater and underground sources. The canals, lakes, and springs that you see are all manmade.
( Underground water must be kept clean )
Given that Copenhagen gets over 99 percent of its water from underground, if its sewage is not properly treated and reused, the consequences of wastewater seeping down to the water table could be devastating.
( Country's biggest sewage plant )
Lynetten is Denmark's largest wastewater treatment plant, and is situated right by the capital. But the perfectionist Danes who run it, say they do not just want to treat wastewater, but recycle and reuse it.
Lynetten Wastewater Treatment Plant manager, Jens Kjaer Christensen:" Sand in the middle and then grease inside here. And then the machine you can see going to and fro here is removing the sand at the bottom and the grease at the top."
( Steps to clean water )
As manager Jens Christensen shows us around, the facilities do not look so different from any other treatment plant. The same steps in the purification process are followed, from sedimentation, to filtering, removing the grease, and then bio-treatment.
Lynetten Wastewater Treatment Plant, Jens Kjaer Christensen:" You see here, bubble. And what is this? This is what we call aeration. Underneath the bridge there, big rotors are running around, and this way taking air with oxygen down to the bacteria into the water."
In this stage, the tank is aerated with oxygen, which allows bacteria to digest the organic waste in the water, producing bubbles on the surface.
Finally the dead microorganisms sink to the bottom of the tank, leaving clean water on top. The sludge at the bottom is thickened, and sent to a digester, where it makes methane gas that can be turned into electricity and heat.
Lynetten Wastewater Treatment Plant, Jens Kjaer Christensen:" Where we will heat up the sludge to 34-33 degrees, and then give very good conditions for the bacteria to work for us, and they will eat and have a good time, and this way we produce for us biogas methane."
( Steps to clean water )
Any remaining sediment is dried and turned into fuel. After the final step of being purified through activated carbon and other filters, all that is left is steam from the chimney.
The plant treats about 80 million cubic meters of wastewater a year, at a cost of 7 US dollars and 50 cents per cubic meter, for a total annual bill of about 600 million dollars. Yet there is more to the purification process than meets the eye.
Lynetten Wastewater Treatment Plant, Jens Kjaer Christensen:" I will bring you down in the underworld."
Lynetten Wastewater Treatment Plant, Jens Kjaer Christensen:" Another world in fact, you don't see it. But this is necessary. You can walk down here for many hours. Not many hours, but some hours."
( Capacity of 41,500m3/hr )
In the bowels of the treatment plant there are so many compressors, that even Jens Christensen loses count. Up to 41,500 cubic meters of water rushes through these pipes every hour. The Danes excel at reusing over 90 percent of the water taken by the pipes to each stage in the process.
Lynetten Wastewater Treatment Plant, Jens Kjaer Christensen:" We try to reuse all the things from the wastewater, or from the process here in the plant. Either we burn it or we recycle it, using it."
( Environmentalism is second nature )
Back on the surface, flowers gentle sway in the sunshine. Being environmentally friendly seems to come naturally to the Danes, who are turning a new page in the story of wastewater treatment and green energy production.
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Water Recycling - Our Planetby nubianwatersystems2,863 views
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