Diseño de un biodigestor para la producción de biogas a partir de las excretas de ganado bovino de raza holstein en la Hacienda La Estancia – Ilapo

Abstract

The aim of this research was to design a biodigester for the obtention of biogas from cattle manure generated by “La Estancia” Farm, located in Ilapo rural parish, Chimborazo province. The experimental design was proposed based on three samples set under thermal improvement conditions. The first sample considered as a control sample, was formed by a manure-water mixture with a two-fold proportional dilution. That is, two kilograms of water per each kilogram of manure, this mixture was compared with samples 2 and 3, adding a 6% and 3 % of molasses regarding the total volume of the substrate. The monitoring of the three experimental biodigesters was carried out during the permanence time of the substrate. So, the temperature and pH data were obtained. On the other hand, the Test tube and flame tests were carried out during the generation of biogas. Some calculations were also applied for the design of a biodigester, which was based on the information obtained from 50 cows producing a daily manure load of 990 kilograms per day; through which the experimental biodigester 2 was chosen taking into account the following parameters: retention time 30 days, total volume of the biodigester 39.6 cubic meters, diameter 3.54 meters and length 4.02 meters. It was concluded that the production of biogas is 9.9 cubic meters per day, which supplies 100% of the required value of liquefied petroleum gas used in the productive activities of La Estancia Farm. It is recommended to expand the research excluding the addition of molasses and implementing specialized thermal improvement which avoids the environmental conditions of the area, the ones which are considered unfavorable for the anaerobic digestion, since the addition of 6% molasses represents a high economic cost, this makes the production of biogas becomes unprofitable.