Increased Gas Yield and Faster Gas Formation
A key factor for the profitability of the Biokraft Ball Mill is the increased methane yield. In order to be able to express this in figures, extensive test series were carried out by the University of Hohenheim in summer 2018 and autumn 2019. In addition, we were able to use the analyzes from the laboratory at the University of Hohenheim to determine the optimal operating parameters and thus optimize the system for the digestion of lignin-rich substrates. Here we would like to show you a selection of these results in order to illustrate the impressive effect of the Biokraft Ball Mill.
Grass Silage
The graph on the left shows a higher methane yield and a faster gas rate for grass silage. After only 14 days, the grass silage milled by the Biokraft Ball Mill (solid line) has achieved a methane yield, which the untreated grass silage (dashed line) had after 36 days. The methane yield of the milled grass silage, which was dry at 39 % organic dry matter (DM), is around 16 % higher: 282 liters CH₄/ kg DM.
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Wheat Straw
When it comes to straw, the gas rate and gas yield play a secondary role even though they are also considerable. The focus lies on the milling of the lignocellulosic material, so that the increased use does not affect the process of the biogas plant. The graph for wheat straw shows that a faster gas rate occurs and the gas yield with 228 liters CH₄ / kg DM is about 13 % above the gas yield of the untreated straw (the latter: dashed line).
Economic Efficiency
The high cost-efficiency of the Biokraft Kugelmühle results from many factors, for example through reduced agitation work in the fermenter, reduced wear and tear from pumps, screw conveyor and agitators, or through increased process reliability, since the risk of floating covers is significantly reduced. A significant cost factor for biogas plant operators can be lowered thanks to the Biokraft ball mill: Costs for substrates can be drastically reduced – by switching to agricultural residues.