German biogas plant pumps up the volume
19 Jan 2012
Kronprinzenkoog, Germany – Biogas producer Biogas Kruse has increased its biomethane generation by 5% at its plant in Kronprinzenkoog in northern Germany, following the introduction of a Landia digester mixing system.
One of only a handful of biogas plants in the Schleswig-Holstein region, the facility is producing about 500kW of electricity per hour at the plant – even though it is still only running at about 30% capacity.
Currently using a feedstock of maize (40%) manure (30%), sugar beet (20%) and milled wheat (10%), Biogas Kruse owner Boy Kruse is also working with a consultant to see if a 2% injection of hydrogen will further enhance the gas yield.
“We are learning and improving all the time,” said Kruse. “Naturally, we want to maximise the gas and run 24/7 so that we can reduce the payback, which is currently around eight to nine years”.
As Kruse works towards generating enough energy to sell onto the National Energy Grid of Germany, Landia’s high-speed, high pressure, multi-pump system is designed with an extended knife system to deal with the long maize fibres that typically try to get to the top of the 1,500m3 tank.
In addition to his primary tank, Kruse’s set-up also includes a secondary tank; currently with a conventional impeller - plus another primary tank and a gas storage tank. Potentially, when operating at 100% capacity, Biogas Kruse could be generating 4MW per day.
“Landia’s external mixing system only requires routine maintenance”, continued Kruse, “but we have already benefited from top quality equipment that is very easy to access - with no downtime, nor labour-intensive emptying of tanks.
“We have lots of potential here, especially when we start using the heat from the biogas too. Already we gain a good quality digestate, which we use and also sell on as a fertiliser, so the process makes a very good closed loop.
“Using such a high concentration of dry matter for feedstock makes us quite an unusual biogas plant, but as we get the liquid to a higher and higher level to increase the gas, we will no doubt become a much larger producer of renewable energy”.
