Straw briquettes for biogas

Agricultural briquetting – Straw briquettes for biogas

Biogas production is increasing in Europe, and so is the demand for raw material. In some countries crops like maize silage have been used as raw material, but there is a political pressure to use 2nd generation raw materials as raw material.

One of the largest resources of raw material for biogas production is wheat straw, however, untreated straw cannot be used in a biogas production, due to the closed pore structure and low density of straw. Straw briquettes, however, can be fed directly into a biogas reactor and effectively be fermented. As a result of the briquetting process, a small steam explosion is created and the cell structure is opened, making access to bacteria and thus being able increase biogas production.

The advantages of using wheat straw briquettes for biogas production

The advantages are numerous including:

  • A 2nd generation technology providing better economy than using maize silage
  • No floating is formed in the biogas tank even at high dry matters. A stable and sound biogas process is achieved
  • 250 Nm3 methane per tons straw can be produced – minimum, at residence times of 30-40 days in thermophile reactors, by using special catalysts the gas production can be further increased.

A biogas plant with supply of 100.000 tons slurry can increase biogas production from 2.5 million m3 of biogas to 6.5 million m3 by adding 10.000 tons straw briquettes.

Kinetic BioFuel A/S

C.F. Nielsen has developed the technology together with a partner, BioFuel Technology and The University of Aarhus in Foulum, Denmark. The development has been supported by a grant by the Danish Energy Ministry’s EUPD Program.

The new concept is marketed through a new company Kinetic Biofuel A/S – see more information at this web-site:

Stored straw bales
Stationary briquetting plant
Two briquetting presses in a mobile solution
Straw Briquettes
Biogas facility