“Corn belongs in the kitchen, not in biogas facilities” – objections like this can be heard more and more frequently. They are protesting against the fermentation of foodstuffs in biogas plants that generate electricity and heat.
One thing the opponents are afraid of is that generating electricity in this way will cause food prices to escalate. In collaboration with several small and medium-sized enterprises, research scientists at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden have developed the first-ever biogas plant that works entirely without edible raw materials.
“In our pilot plant, we exclusively use agricultural waste such as corn stalks – that is, the corn plants without the cobs. This allows us to generate 30 percent more biogas than in conventional facilities,” says IKTS head of department Dr. Michael Stelter. Until now, biogas plants have only been able to process a certain proportion of waste material, as this tends to be more difficult to convert into biogas than pure cereal crops or corn, for instance.
This is not the only advantage: The time for which the decomposing waste material, or silage, is stored in the plant can be reduced by 50 to 70 percent. Biomass is usually kept in the fermenter, building up biogas, for 80 days. Thanks to the right kind of pre-treatment, this only takes about 30 days in the new plant. “Corn stalks contain cellulose which cannot be directly fermented. But in our plant, the cellulose is broken down by enzymes before the silage ferments,” Stelter explains.
The researchers have also optimized the conversion of biogas into electricity. They divert the gas into a high-temperature fuel cell with an electrical efficiency of 40 to 55 percent. By comparison, the gas engine normally used for this purpose only achieves an average efficiency of 38 percent. What is more, the fuel cell operates at 850 degrees Celsius. The heat can be used directly for heating or fed into the district heating network. If the electrical and thermal efficiency are added up, the fuel cell has an overall efficiency of up to 85 percent.
The overall efficiency of the combustion engine is usually around 38 percent because its heat is very difficult to harness. The researchers have already built a pilot plant with an electricity output of 1.5 kilowatts, enough to cover the needs of a family home. The researchers will present the concept of the biogas plant at the Hannover-Messe on April 20 to 24 (Hall 13, Stand E20). In the next phases of the project, the scientists and their industrial partners plan to gradually scale up the biogas plant to two megawatts.
Dr. Michael Stelter | EurekAlert!
Linear potentiometer LRW2/3 - Maximum precision with many measuring points
17.05.2017 | WayCon Positionsmesstechnik GmbH
First flat lens for immersion microscope provides alternative to centuries-old technique
17.05.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Earth Sciences
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy