Stickstoffemissionen als Folge mineralischer Stickstoffdüngung in Kurzumtriebsplantagen mit Weiden und Pappeln

Ein entscheidendes Kriterium für die Nachhaltigkeit der Produktion Regenerativer Energien ist die Umweltwirkung der mineralischen Stickstoffdüngung. Diese wurde in praxisnahen Parzellenversuchen am Standort Potsdam-Bornim untersucht. Bei dem Standort handelt es sich um eine Grundmoräne mit Pseudogley-Braunerde mit schwach lehmigem Sand. In tieferen Schichten ist Mergel zu verzeichnen. Weiden (Salix viminalis Klon Inger) und Pappeln (Populus maximovizcii x P. nigra Klon Max 4) wurden auf Ackerland im zweijährigen Kurzumtrieb auf schwach lehmigem Sand in einer randomisierten Blockanlage mit vier Stickstoffdüngestufen (0, 25, 50 und 75 kg N ha-1a-1) angebaut und auf Nitratauswaschungen (mittels Selbst-Integrierender Akkumulatoren) und Lachgasemissionen analysiert. Zur Erstellung einer Stickstoffbilanz wurden zusätzlich die in Ertrag und Begleitflora enthaltenen Stickstoffmengen, die Bodennährstoffgehalte und die atmosphärische Stickstoffdeposition berücksichtigt. Nach drei Versuchsjahren waren durch die Stickstoffdüngung keine signifikanten Ertragsunterschiede, jedoch deutlich höhere Auswaschungen, Begleitfloramengen und Lachgasemissionen pro Ertragseinheit zu verzeichnen. Die prozentualen düngeinduzierten Stickstoffverluste durch Auswaschung betrugen in der 75 kg N ha-1a-1- Variante im zweiten Anbaujahr bei Weiden 33 kg ha-1a-1 und bei Pappeln 35 kg ha-1a-1. In Weiden stieg die Masse der Begleitflora durch Stickstoffgaben von 75 kg N ha-1 a-1 um 46 %, die darin enthaltenen Stickstoff-gehalte stiegen um 52 %. Auch in Pappeln waren sie tendenziell erhöht. Die Lachgasemissionen stiegen in Pappeln und Weiden um maximal 0,2 kg N ha-1a-1

Testing a PEM Fuel Cell System with Biogas Fuel by Ralf Schmersahl and Volkhard Scholz

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 7 (2005): Testing a PEM Fuel Cell System with Biogas Fuel by Ralf Schmersahl and Volkhard Schol

Производство и использование экологически чистого биотоплива

In clause results of experiences on cultivation of fast-growing power plants are stated. Experiences carried out on sandy ground with entering nitric fertilizers of 150 kg and 75 kg of working substance on 1 ga a and without use of fertilizers. Defined an output of dry substance and initial energy at burning a biomass. At carrying out of experiences on bracketing a mix of wood sawdust and crude glycerin the maximum permissible quantity of the last in a mix (20%), heat of combustion and issue of oxides of nitrogen in an atmosphere has been determinedVytauto Didžiojo universitetasŽemės ūkio akademij

New technological processes and investigation methods for agricultural engineering : proceedings of the international conference, 8-9 september 2005

The energy input and output are two important factors used to determine the energetic and ecological uselfulness of a fuel or its production technology. In the following paper 24 methods for 5 different biofuels, which can be rpoduced in agriculture and forestry are analysed and energetic balances are drawn up for them. A balancing develop in the ATB Potsdam-Bornim is used for this. The program is based on the recent guideline VDI 4600 of the Association of German Enginners, with ensures reliability and comparability of the results. The results show that the energetic input is relatively low compared to the output, especialy for by-product and residual substances such as cereal straw and forest clearing timber. Whenever fuel crops are cuiltivated, the energetic efficiency is critically determined by the quantity of nitrogen appliedVytauto Didžiojo universitetasŽemės ūkio akademij

Augalų biomasės nuėmimo ir ruošimo kurui technologijos ir vertinimas : studija

Vytauto Didžiojo universitetasŽemės ūkio akademij

Harvesting machinery for short rotation coppices

Numerio antraštė: Biosystems engineering and processes in agriculture : 25-26 September, 2008, [Raudondvaris]The mechanisation in harvesting of short rotation coppices on farmed land is a prerequisite for swift and low-cost provision of this source of bioenergy. We can distinguish between three process lines: trunk wood, bundle, and chopping lines, whereby the latter are the cheapest. In the past more than 20 different harvesting machines and assemblies have been developed for this alone, but they have rarely progressed beyond the prototype stage. In addition to special cutter tools already available for field choppers, lower cost mounted assemblies for tractors also have a good chance on the market. However, these still require considerable development and optimising inputsVytauto Didžiojo universitetasŽemės ūkio akademij

Энергетические аспекты производства и использования биотоплива

Vytauto Didžiojo universitetasŽemės ūkio akademij

Effiziente Aufbereitung von Biogas zur Verstromung in PEM-Brennstoffzellen : Schlussbericht im Auftrag der Fachagentur Nachwachsende Rohstoffe e.V.

[no abstract available

Problemi i rešenja za skladištenje drvenih čipsova u rasutom stanju

Wood, including short rotation coppice, is a promising biofuel. Most of this wood is transported, stored and used as chips. The storage of chips of recently harvested wood in unventilated piles causes difficulties. Due to the high water content microorganisms, above all mould fungi, develop and result in high temperature and losses of dry matter. The first is bad for the operator’s health and the latter cause a relevant loss of energy and money.Šumska stabla i usevi sa kratkom rotacijom predstavljaju značajan izvor biomase. Većina ovih materijala se transportuje, skladišti i koristi u formi čipsa. Kod kultura koje se odmah nakon ubiranja i usitnjavanja skladište, može doći do problema. Obzirom na visok sadržaj vlage i mikroorganizme, posebno gljive, dolazi do povišenja temperature u skladištima što uzrokuje gubitak u suvoj materiji. Sve ovo je negativno kako po zdravlje radnika tako i po ekonomsku i energetsku efikasnost

Prospects and risks of the use of castor oil as a fuel

Castor oil is more than just a raw material in great demand by the pharmaceutical and chemical industries. In several southern countries its use as a fuel is also being discussed in connection with social and ecological aspects. A few properties, in particular the extremely high viscosity and high water content, complicate the use of straight castor oil as a fuel for internal combustion engines. A better perspective may be possible by transesterification and the addition of this biodiesel to fossil diesel fuel. This, however, calls for considerably lower castor oil prices than are at present being paid on the world market