IFAT: Hidden Energy Potential in Waste Materials


Merely disposing of waste safely or cleaning up polluted water to make it safe is today just the start: Increasingly the emphasis is also on tapping into the energy potential that is hidden in waste materials, waste water and exhaust air. The latest technology and solutions to cope with these challenges are to be showcased between May 5 and 9, 2014, by exhibitors at IFAT, at the Messe München exhibition center.

In the European Union’s Landfill Directive of 1999, the declared aim was to minimize the overall volume of waste being dumped. This makes Europe, alongside East Asia, the largest market for waste-to-energy solutions. According to a recent report by market researchers Frost & Sullivan, in 2012 the European market for waste-fuelled power plant achieved earnings of $4.22 billion. By 2016 this figure is set to rise to $4.94 billion.

As regards construction of new waste-to-energy plants, Great Britain and Poland are seen as the most attractive and active markets for the coming years. However, in Germany, France and Scandinavia – the nations that pioneered thermal treatment – the Frost & Sullivan analysts are expecting the market to pick up, prompted by the need to modernize older plant, some of which dates back decades.

Outside of Europe, China in particular is increasingly turning to waste incineration. Ecoprog, a consultancy specializing in energy and environmental themes, expects that in each of the next five years a total of 125 facilities, with capacities of 40 million tonnes p.a., will go online in China.

Alongside combustion, gasification is another way of extracting the energy potential in waste. Here, processing of methane to natural gas quality offers new perspectives. This enables, for example, the gas obtained from organic waste in biogas plant to be fed into the general supply pipelines for natural gas, thus creating new logistical and business opportunities. In the US, large waste-disposal companies have come up with an interesting and neat idea: increasingly they are turning landfill gas into fuel for their natural-gas powered waste-collection vehicles.

But it’s not just solid waste that contains hidden energy – so, too, does sewage. In Germany last year, for example, over 1,200 gigawatt-hours of electricity were generated by sewage treatment plants. That’s enough to meet the electricity requirements of around 360,000 households. And there is significant potential still to be tapped here: Only around 1,200 of the 10,000 sewage plants in Germany are currently making use of the gas produced in the process of treating sewage sludge.

Even before waste water reaches the treatment plant, the energy within it could be extracted. Because this domestic, commercial and industrial waste water runs in a permanent, warm flow beneath our feet in the sewage pipes – at temperatures of between 12 and 20°C. Channeled through special heat exchangers, this energy potential could be tapped into and, via a heat pump, be used to heat or cool buildings. According to the "Themenallianz Abwasserwärmenutzung", an alliance of companies, service-providers and research institutions involved in heat recovery from waste water, around six percent of all buildings in Germany could in theory be heated in this way. The alliance puts the figure of such plants currently in operation in Germany at around 35.

The environmental technology developers are also focusing their attention on air: Using clever combinations of processes, exhaust air from industrial applications could be used in place of fossil fuels. Recently it has become possible, for example, to concentrate and process vapor from solvents in such a way that it can be burned in adjacent steam boilers or in co-generation plants, like natural gas.

More articles on this topic