Methane production from bread Kursu and potatoes Vineta waste and effect of catalyst metaferm

Abstract

There are significant quantities of different food wastes, which cannot be consumed for food in Latvia. Foods popular in Latvia are rye bread Kursu and potatoes Vineta. The significant part of this food was diverted to waste due to non-standard, surplus production, bad storage conditions, shelf life limitations and wastes accruing during food consumption by consumers. Food wastes, when disposed in landfills, will degrade easy in aerobic conditions releasing harmful gases, including gaseous nitrogen compounds and carbon dioxide. Also, food wastes disposal in landfills are limited now and expected to be avoided in future according to the respective EU Directive on disposal of easy degradable wastes. Damaged bread and potatoes peels may be utilised in the biogas production process. There is an interest to investigate the effect of usage of additives, e.g. catalyst Metaferm, to enhance the methane production during the anaerobic fermentation process. In previous studies, the addition of catalyst Metaferm caused the improvement of methane extraction from substrates with difficultly biodegradable corn silage and dried grains. Therefore, this study continues to examine the effect of the additive Metaferm on more easily fermentable biomass. To find the methane volume obtainable from bread Kursu and potato Vineta wastes, a study was conducted in 16 bioreactors at the temperature of 38 ºC. The specific methane volume 0.459 l•g-1 DOM or 0.515 l•g-1 DOM were obtained from rye bread Kursu or potatoes Vineta respectively, after 30 days anaerobic digestion (AD) process. The addition of Metaferm increases the methane yield by 5.4 % or 2.3 % from rye bread or potato wastes, respectively. Investigation results show that both food wastes can be utilised in biogas plants for energy production successfully.

Increasing the Bio Gas Release During the Cattle Manure Fermentation by Means the Rational Addition of Substandard Flour as a Cosubstrate

“…Analysis of recent research and publications on the grain waste disposal show that their anaerobic processing is the most effective for biogas production. According to the results of the study described in research [3], the re lease of biogas at a fermentation temperature of 38°с from substrates with the addition of rye bread is 0.459 l/g dry organic matter (DoM), in research [4], various types of grain release -from 0.634 l/g DoM (for rye bread) to 0.943 l/g DoM (for wheat bread with egg and milk additives). As it is stated in research [5], the common fermentation of biowaste with the waste of wheat and rye bread with an organic loading ra te of 14 kg/m 3 per day, was stable to their organic loading rate kg/m 3 per day and enabled producing 3 times mo re biogas.…”