Press release BoxID: 172057 (Fritsch GmbH)
  • Fritsch GmbH
  • Industriestraße 8
  • 55743 Idar-Oberstein
  • Contact person
  • Andrea Köhler
  • +49 (6784) 70-146

Silage for biogas

New ideas are necessary for the production of renewable energy sources.

(PresseBox) (Idar-Oberstein, ) Loppings of diverse origin are increasingly used for the production of biogas. Thereby is the construction of biogas plants and their optimisation in regards to science still a broad field of activity.

The task consisted of processing fresh silage, as well as corn and grass silage in the same manner. Goal of the work is the determination of the chemical oxygen demand the CSB value.

For this purpose various suppliers offer ready made testing solutions, for example CSB according to Dr. Lange or by Riedel-de Haen the vessel test 37737 „AQUANAL“. Hereby, the mass of oxygen per volume unit which reacts in standardised conditions with the in water suspensions contained oxidisable substances, is measured as a potassium dichromate equivalent in a sulphuric solution via photometry. The CSB value correlates with the results of the fermentation tests of organic substances performed according the guideline VDI 4630. This offers uniform rules and specifications for the practical applications of fermentations tests, which serve the operational optimisation of biogas plants. For further information about the production of biogas please refer to . Those more interested in the basics, should search in the internet for Martin Kaltschmitt an author in regards to Energy made of biomass.

FRITSCH was given the task, to process fresh grass silage with a higher degree of moisture, in a manner, so that a homogenous sample would evolve. Chosen was the planetary mill PULVERISETTE 6 classic line in combination with a 250ml cup made of sintered corundum and balls of 30 mm diameter. From tests with other tough, elastic materials it is known that the slightly rough surface of sintered corundum has a very positive influence on the comminution.

During the tests a buffer solution was added to the silage. Therewith the solids content was lowered. After four minutes the material was extremely well ground. Temperature readings were also in a normal range and therefore thermal damage was not to be expected. The established CSB values were clearly different though form the CSB values of the samples prepared with previous methods. It became therefore clear, that the processing of the samples has a significant influence on the test value of the chemical oxygen needs. Since it depends more on the comparability with the existing data rather than the absolute values, the preparation was matched to the previous mode.
For this the silage was pre-crushed in a household mixer and then finely comminuted in a planetary ball PULVERISETTE 6, equipped with a 250 ml steel cup and 20 mm balls. With this preparation, comparable results in regards to the empirical values and the correlation with the batch tests of the produced methane yields are achieved.

Dry as well as fresh materials can be

The fine comminution is carried out with the planetary ball mil PULVERISETTE 6. The photos illustrate the condition before and after the treatment with the ball mill.

This procedure is more elaborate and evaluating it visually a not so homogenous final product evolves. But all decisive though is the comparability of the CSB values with other values and the correlation of the in laboratory tests produced amounts of methane.

Fritsch GmbH

FRITSCH: Your specialist in the processing laboratory

FRITSCH is the world-wide leading manufacturer of instruments for sample preparation and particle size analysis in the laboratory. Since 87 years now, the company is concentrating on the three product groups and identified with the brand names of PULVERISETTE, ANALYSETTE and LABORETTE in research and industrial laboratories. The FRITSCH name is synonymous with technical competence and economical efficiency in all matters in the field of

milling - particle sizing - dividing

Because FRITSCH operates throughout the world, they have the unique advantage of vast experience in a wide variety of scientific disciplines which enables them to offer constructive solutions to ease problem solving. FRITSCH laboratory instruments ensure proven, extreme longevity, highest quality and innovative technology in combination with simple operation.

Here a short view of the FRITSCH instrument range:

Mills for analytical sample preparation
FRITSCH offers an entire range of instruments for crushing, grinding, fine-milling, mixing and homogenising of hard-brittle, fibrous, elastic to soft materials dry or in suspension. The FRITSCH variety of grinding mills includes different ball mills, planetary ball mills, cutting mills, rotor mills, jaw crushers enables an optimal adjustment of the grinding process to the sample material and the following analyse.
Show us the sample, which you can’t manage to grind and we’ll show you the instrument which can do it!

Sieve Shakers and Laser Particle Sizers for particle size determination
FRITSCH with their vast experience in the particle sizing field offers Sieve Shakers as well as Laser Particle Sizers in different version.
FRITSCH offers due to its equipment varieties for each special use and application a particle size measuring instrument, which uses the most modern laser technology or the well-tried and reliable sieving method and this with an unbeatable price-to-performance ratio.

Laboratory instruments for analytical sample handling
The FRITSCH instrument range also includes sample divider and feeder, because representative sample dividing of dry samples or suspension as well as controlled and uniform sample feeding for mills and other instruments are basic conditions for reliable and precise analysis.

In addition to the complete programme of laboratory instruments, FRITSCH also offers a comprehensive range of services with Workshops, product presentations with the FRITSCH-Mobile laboratory bus on your door step, test milling or particle size analysis of your sample at no charge and much more.

Please use our instrument search engine and our grinding report data base on the FRITSCH-Homepage under – sample preparation – solutions. Here you will find your suitable instrument as well as a comparative grinding report comparable with your application.

Make use of our decades of experience. We can facilitate your work substantially.