Avaliação da viabilidade técnica e ambiental do uso do conteúdo ruminal bovino como biocombustível

Abstract

The search for solutions to recovery waste for energy is already a reality in industries from different sectors, since the benefits in reducing the volume and improvement in waste management, besides the possibility of energy trying to replace other sources of energy. In slaughterhouses, this case can be applied to paunch from the rumen of cattle. This studyaimed to evaluate the technical feasibility and environmental use of the paunch as biofuel. Potencial problems can be related with the high humidity and the potential for formation of dioxins and furans, resulted from presence of chloride (mineral salt) used for feeding cattle. Two composite samples were taken in a slaughterhouse, the characterization of paunch were done in four points in the unit, followed by firing tests to determine the best proportion of mixing with a fuel supplement, in a next step was realized the determination of some pollutants, including dioxins and furans. The results showed an average generation of paunch for the unit after the press of drainage around 24,7 kg/animal slaughtered, with an expected generation of waste from 3,360 ts/year. Among the main features of the pressed material PCI was 16,67 MJ/kg. To the natural conditions of the material and the wood used to feed the boiler it was estimated that 20 % of wood could be replaced by pressed paunch. The press operated with efficiency of removal of liquid from 2,3 % and 17,6 % for the two days tracked, the average removal of liquid was around 386,4 m3/year. As the chlorine present in the residue, it was a content of 0,15 % (m/m), below some european specifications. In test firing, the proportion in the most favorable to the mass burning was 1 : 1 using the chip, the moisture of the mixture to the monitoring of air pollutants was 35 % and a PCI of 16,58 MJ/kg. Of the pollutants monitored, the concentrations of dioxins and furans and metals (Fe, Cu, Mg) were below national standards. The obtain carbon credits can be a reality. For a period of 21 years it was estimated of 37.303 t CO2e avoided. Because of not sending the paunch to landfill, anaerobic degradation wont be happen in material, and with this project the gross income was estimated of R$ 1.235.478. It follows that paunch can be used for energy, while the remotion of moisture in biofuel and the final operational control over the burning of the material is a necessity.