摘要 |
<p>Lime soaps and/or magnesium soaps, notably the former, are used as energy supplement in the production of biogas. Hereby there is obtained an increase of the biogas production and especially it is advantageous to use the fat supplement as a part of the material under fermentation in the biogas reactor in the form of lime soaps (magnesium soaps) because thereby the foaming is avoided which will occur if the fat is used as free lipid; the foaming occurs because the fatty acids formed by hydrolysis of the fats form ammonium soaps at the pH of about 7 normally prevailing in the reactor because of nitrogenous compounds in the material under fermentation, e.g. liquid manure or sewage sludge. It is specially advantageous to use lime soaps of waste fats and oils as a part of the fermenting material in biogas reactors because hereby one in addition achieves a utilization of waste fats the disposing of which often causes problems.</p> |