Molecular analysis of microorganisms involved in the fatty acid volatiles and hydrogen production in the treatment of vinasse from sugarcane by anaerobic digestion

Abstract

Brazil is one of the largest producers of ethanol from sugarcane in the world, a product that is used mainly as automotive fuel. In this process are generated high volumes of liquid waste known as vinasses. Vinasses are used in fertigation in the crops of the sugar cane itself. It is known that these practices generate environmental impacts mainly in the contamination of rivers and groundwater and for long periods can cause soil salinity, among others. One of the possible alternatives for these practices is the use of the acidogenic phase of anaerobic digestion to produce volatile fatty acids (acetic, propionic and butyric acids, fundamentally) and hydrogen (H2), that is, products with higher added value. These acids can be extracted and used in the chemical industries and in this way contribute to the reduction of the use of petroleum derivatives and H2 could be used as fuel in the industry itself. The objective of this project is to carry out studies on the identification of microbial populations involved in the production of these products by digestion anaerobic in batch cultures and in fixed packed bed reactors and using as substrate vinasses. These studies will use molecular analysis techniques that include the new-generation DNA sequencing methods, the quantification of these communities by PCR on real-time and the isolation of the predominant microorganisms by classical Microbiology. The information obtained will allow to select and characterize the inoculum microorganisms that are most suitable for these purposes and in this way to achieve an optimal functioning of the productive processes in a stable and efficient way.