Stanley Ribeiro Centurion

Effect of different substrates on composting of poultry litter

The objective was to evaluate the differences between distinct types of litter material and their combinations in the dynamics of degradation on the organic matter fractions and the quality of the final compound. The treatments were established according to material used as substrate for broiler litter: treatment 1 - rice husks; 2 - sugar cane bagasse; 3 - wood shavings; 4 - wood shavings + sugar cane bagasse; 5 - rice husks + sugar cane bagasse; and 6 - Napier grass. The following variables were monitored: temperature, levels of total solids (TS), volatile solids (VS), mass and volume of the pile, fibrous fraction, and levels and reductions of N, P and K during the process. Piles formed with Napier grass and sugar cane bagasse presented the highest average temperatures during composting. The greater average reductions in TS and VS were attained in piles with sugar cane bagasse (68.12 and 73.07%, for TS and VS, respectively). The reductions of greatest volume occurred in piles with sugar cane bagasse (52.08%), followed by Napier grass (50.56%). Poultry litters composed of rice husks and wood shavings presented 13.21 and 10.23% of lignin, respectively, which contributed to the lower degradation of fibrous fraction and degradability. Substrates with lower lignin content were those with greatest organic matter degradation rate and had reduced losses of N levels during the process. Composting performance is affected by the initial substrate used to compose the poultry litter.

Biodigestão anaeróbia de dejetos de poedeiras coletados após diferentes períodos de acúmulo

The objective was to evaluate the interference of the time of accumulation of waste on the performance of the anaerobic digestion process of waste from laying hens. The experiment was conducted in a completely randomized design with four treatments, which observed 1, 8, 15 and 22 days of accumulated waste with five repetitions per treatment, with a total of 20 digesters. It was used batch digesters of bench with useful capacity of 3 liters of substrate fermentation. The efficiency of digestion was evaluated by reductions in total solids (TS), volatile solids (VS), most probable number (MPN) of total and thermotolerant coliforms, beyond the production and potential of biogas production. There were significant reductions in the levels of VS present in the laying hens waste as it increased the days of accumulation, being observed a level of VS (in percent of TS) of 97.1 and 75.6% of VS for 1 and 22 days of accumulation, respectively. The reduction in VS contributed to reduce the production and potential of biogas production as it increased the days of accumulation, and observed a 37.2% of reduction in the potential production of biogas kg VS-1 between the lowest and longer period of accumulation, or 6.81 liters less per day accumulation for each kg of VS added. It was also observed reductions of 100% in the MPN of total and thermotolerant coliforms at the end of the process, independent of the tested treatment. The storage time reduces the potential production of biogas from manure layers.

Biodigestão anaeróbia de efluente de abatedouro avícola

Anaerobic digestion of broiler slaughterhouse wastewater The objective of this study was to evaluate the process of anaerobic digestion treatment of poultry slaughterhouse wastewater, considering hydraulic retention time (HRT) of 7, 14 and 21 days, plus the addition of lipolytic enzyme to the substrates at concentrations of 0; 0.5; 1.0 and 1.5 g L -1 charge added to the digesters. The influence of HRT and the addition of lipolytic enzyme to the substrates was evaluated by biogas production and CH 4 production potentials for COD (chemical oxygen demand) added and removed as well as by reductions in the levels of COD, concentrations of N, P and K and pH values. The results showed that there was influence of HRT (HRT 7 in which the expressed best results, average weekly production of biogas with 40.7 L -1 and 32.2 L -1 CH 4 ) and concentrations of enzymes with higher production values to treatments 1.0 (24.6 L) and 1.5 g L -1 (26.2 L), which did not differ. The enzyme concentrations of

Effects of biofertilizer rates on the structural, morphogenetic and productive characteristics of Piatã grass

Univ Estadual Paulista Julio de Mesquista Filho, Programa Posgrad Zootecnia, Rio de Janeiro, Brazil