EMPLOYMENT OF MAIZE SILAGE IN NON-LIQUID FERMENTATION FOR BIOGAS PRODUCTION

Abstract KARAFIÁT, Z., VÍTĚZ, T., SOMERLÍKOVÁ, K., GADUŠ, J., HAITL, M., KOUTNÝ, T.: Employment of maize silage in non-liquid fermentation for biogas production. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 6, pp. 153-160 This paper deals with the optimization of the anaerobic fermentation process of maize silage using the non-liquid technology. The aim of the paper is to increase the knowledge necessary for more effi cient running of biogas stations using batch technology of non-liquid fermentation. The preferable ratio of initial materials, fresh maize silage and maize silage a er partial fermentation, was verifi ed within this experiment. Dynamics of the process, especially the quantity and quality of produced biogas has been monitored during the experiment. All the experiments have been done in the batch-system fermentors of volume of 0.48 m 3 equipped with an independent and indirect circuit of water heating, the heat has been transferred to the material throught the steel wall of the fermentor. The material has been tested in the mesophilic conditions with the temperature of the 38 °C. The retention time of material in fermentors has been 27 days. The results of our experiments reveal the fact that the maize silage of lower mix ratio produced about 22.8 % more of biogas counted to one kilogram of dry matter than the maize silage of higher mix ratio. non-liquid substrates, anaerobic fermentation, biogas, maize silage Transformations of biogas off er a large scale of advantages in comparison with the other technologies using the renewable sources of energy. Biogas technologies were evaluated as the most power-effi cient and ecologically rewarding technologies of energy production coming from renewable sources (Fehrenbach, 2008). One of the perspectives according to which technologies of biogas production can be distinguished is the content of dry matter (DM) in the processed material. Generally speaking, when the content of dry matter is up to 15 % we talk about technology of liquid fermentation otherwise when the content of dry matter is higher we talk about non-liquid fermentation. Due to the absence of complete information about the process of fermentation of non-liquid substrates, laboratories for research of non-liquid fermentation have been put into operation. This project was implemented by FORTEX AGS Ltd. in cooperation with Mendel University in Brno. This paper deals with the use of maize silage in non-liquid fermentation technology. It is usually the discontinual technology with percolate spraying, without mechanical mixing of fermented material, which is used for fermentation of energy crop

USE OF BIO-ENZYMATIC PREPARATIONS FOR ENHANCEMENT BIOGAS PRODUCTION

Abstract VÍTĚZ, T., HAITL, M., KARAFIÁT, Z., MACH, P., FRYČ, J., LOŠÁK, T., SZOSTKOVÁ, M.: Use of bioenzymatic preparations for enhancement biogas production. Acta univ. agric. et silvic. Mendel. Brun., 2011, LIX, No. 3, pp. 203-208 Biogas is a renewable energy resource with high increasing developed in last few decades. It's big opportunity for stabilization rural areas, concretely agriculture sector. This technology can decentralize supply of energy. The number of operated biogas plants is rapidly increasing. Biogas plants require a high level of intensity and stableness of the process of anaerobic fermentation with biogas production for effi ciency treatment, also for good quality of development biogas and fertilization eff ect of the rest of fermentation. If this is not completed the operator has problem to keep the process in optimal condition for anaerobic fermentation. Researchers have tried diff erent techniques to enhance biogas production. In order to achieve the aforementioned state, it is essential to ensure increased activity of microorganisms that contribute to the anaerobic fermentation. The metabolic activity of microorganisms is preconditioned by availability of easily decomposable solids. Adding of bacterial and enzymatic cultures into a fermented substrate represents one of the possibilities. The enzymes contained in this preparation are responsible for better exposing methanogenic bacteria to the material. The tested bio-enzymatic preparation, APD BIO GAS, is a mixture that contains bacteria and enzymes which are essential for the effi cient progress of anaerobic fermentation. The reference biogas laboratory of the Mendel University in Brno was used for the purpose of testing of APD BIOGAS in mesophilic conditions of anaerobic fermentation on a substrate consisting of a mixture of maize silage and liquid manure. The producer of this preparation declare enhancement of quality and quantity of developed biogas, elimination of smell level of the rest of fermentation its higher homogenity. For the test were used lab scale fermenters of batch type with work volume 0.12 m 3 . An increase of biogas production by 15% was determined in connection with addition of the preparation, also with higher decrease of total solids and decrease of organic substance in total solids in the fermenter where were used this preparation. biogas production, anaerobic fermentation, enzymatic preparations Functionality of our society is currently dependent on exploiting of the limited amount of non-renewable resources of energy. The everincreasing energy demands force us to look for a replacement of the non-renewable resources of energy by other (renewable) resources. One of the available alternatives pertains to use of biomass within the process of anaerobic fermentation resulting in creation of biogas that may be further used for energy-related purposes. Anaerobic technologies off er an attractive manner of use of biomass resources for the purpose of partial satisfying of the energy needs of our society Anaerobic fermentation is a process typical for decomposition of organic matter without in an environment in which air is not present. It consists of four stages: hydrolysis, acidogenesis, acetogenesis and methanogenesis. In the course of individual stages high-molecular substances such as fat, carbohydrates, proteins, nucleic acids, etc., are decomposed into low-molecular substances including their subsequent transformation into the acetic acid, carbon dioxide and hydrogen