The idea is fascinating: Trees provide cellulose as a raw material for newspapers and then recycled newspapers become the basis for the cellulose insulating material produced by Isocell GmbH
, situated in Neumarkt am Wallersee. Just like that, house owners can save energy and reduce the output of CO2
-emissions for years.
This project ist supported by Salzburger Nachrichten
But there comes the time, when any building must be renovated. Can you extract the old insulating material, turn it into pellets, carbonise it, use it to improve the slurry and thus make it an excellent fertilizer for agricultural use that contains trace elements? It would be a perfectly sustainable cycle of material. Students of HBLA Ursprung are now trying to get to the bottom of this question.
„We have carbonised the Isocell insulating material with the company Sonnenerde
in Burgenland, which owns the only officially licensed carbonising furnace “ project manager Prof. Dr. Konrad Steiner points out. „The Austrian Agency for Health and Food Safety,
, has tested the material for all kinds of toxins like heavy metals, dioxins etc. We are very proud the new product was below all threshold values. Our concerns for possible heavy metal contamination in printing ink were unfounded. “
Then the students divided a field located close to the school building in half. On one half they spread slurry mixed with carbonised insulating material, on the other half the same amount of pure slurry.
Beforehand, they had taken samples from the soil in order to compare the current state of the field to the future one. Theresa Brunauer, one of the students, tested these samples at the laboratory of the Institute for analytical chemistry at Karl-Franzens University in Graz,
. „We added boric acid as a flame inhibitor. Thus, the cellulose doesn’t burn, it only smolders, “Sebastian Wallner, another student of grade 3, explains. „And it’s exactly this trace element, Bor, that corn needs to thrive and form full cobs. “A 140 kg amount of carbonised insulating material was then mixed with 1 m3 of slurry and were spread evenly on 6075 m2 of fields. This implied a peculiar side effect: The odour of the slurry was no longer as intense. Possibly the carbon absorbed the bad smells. This phenomenon is now being examined by Ursprung student Thomas Stocker and students from the course of bio-and environmental technology of the technical college of FH Wels
. Measuring and assessing smell professionally is a complex procedure.
On both test fields the students cultivated silage corn and added 5% sunflower seeds. Seven students observed the growth of the corn and the sunflowers, compared the test and control fields and constantly drew samples, which were then sent to the university of Graz. These chemical-analytical results will be documented in detail for their theses and everybody is waiting excitedly for them.
At the end of September the silage corn was chopped, wrapped in bales and weighed. The fields were then precisely measured again and the results were evaluated. These calculations revealed an amazing surplus yield of 7% on the field fertilised with carbonised insulating material. Due to flaws in harrowing and the fact that many of the sunflowers had been stolen, a small area had to be subtracted in the evaluation. This means an error range of 1%. A surplus yield of 6% can now safely be considered as minimum , the maximum could be as much as 8%. The additional yield of 7% (+/-1%) was visible early on as the students observed growth. They witnessed the corn fertilised with carbonised insulating material blossoming 8 days earlier and these cobs had fat kernels up to the tip.
As soon as the silage bales have finished fermenting, we will carry out another comparative analysis on the feed. More corn also mean more energy for the cows.
We want to thank in particular our farm manager Franz Griessner, who has supported all tests with a lot of commitment and who also helps to take care of the students‘ theses. In September 2016 HBLA Ursprung started a new branch, Management of Resources and Environment. This model project for climate-friendly closed-loop recycling management has already taken on board a number of strong partners from science and economic enterprises for up-to-date and practice-oriented teaching. At the moment farmers are not allowed to spread recycled insulating material as a fertiliser, as it is illegal to apply waste to fields. With this experiment the students set out to prove the usefulness of this idea and to show a new utility for used insulating material. In the course of the school year 2016/17 four further field tests have been planned, another 15 in the following year, as more research needs to be approved.
We are particularly proud of the support of Dr.Dr. Wackernagel, the inventor of the ecological
footprint and president of Global Footprint Network.
Here you can find his letter: