Environmentally friendly energy
from sewage sludge
The thermal utilisation of sewage sludge as a sustainable disposal method is gaining momentum.
In Hanover-Lahe, enercity Contracting GmbH has built an incineration plant in which around 130,000 tonnes of dewatered sewage sludge are recycled in a particularly energy-efficient special furnace and used to generate energy.
Anyone looking over the site here would have no idea that just a few months ago, an 80 cm thick conductor line had to be laid across the facility at an angle and thick cables had to be hoisted vertically 22 meters high.
We were tasked with installing the entire E&C cabling – some of it at a height of 30 meters and only using gratings as walkways. Over several floors, 1,300 measuring points were networked, 230 kilometres of cable laid, routes extended, medium and low-voltage systems set up and lighting installed. A challenge that made the hearts of our 40 or so employees involved beat faster – across locations from Visbek through to Doberschütz, Lebus and Burg all the way to Poland.
Residents from the Hanover-Lahe region will benefit of this in the near future. The surplus energy generated during incineration is fed into the district heating network, supplying around 5,000 households with climate-neutral heat.
And not only that: Once the sewage sludge has been incinerated, the phosphorus produced can be recovered from the ash and further utilised. A procedure that will be prescribed by law starting from 2029. Previous disposal methods, such as co-incineration in coal-fired power plants or direct application in agriculture, are becoming increasingly hard due to growing restrictions. The thermal utilisation of sewage sludge as a sustainable disposal method will therefore continue to play an increasingly major role in the future.
