C HEMICAL P RETREATMENT OF C ATTLE M ANURE TO I MPROVE B IOGAS P RODUCTION
: Great potential in gas production is found in raw materials of organic origin, such as manure, waste sludge, food residues and the like. In order to speed up the process of biogas production, that is, the first stage of hydrolysis, it is necessary to pre-process the substrate. In order to obtain the maximum amount of biogas, the anaerobic digestion process was carried out in mesophilic conditions for 37 days. For the purpose of examining the effects of pretreatment, the substrate was chemically treated with the addition of dehydrated CaO in quantities of 0.75% and 1.5% in relation to the mass of the substrate. The results showed that by treating cattle manure with the addition of 0.75% CaO, higher daily production of biogas with a higher methane content is achieved. The total amount of biogas obtained with the addition of 0.75% CaO was 5247.21 ml, while the highest methane content was 61.24%.