Conclusions
The results of this work reveal the potential of anaerobic digestion of pig manure as an alternative to improve living conditions in Parque Porcino de Ventanilla: first of all, by substituting current manure dumping and incineration, thus reducing environmental pollution and hazards to human health, as well as allowing the recycling of this organic material through land application of the organic fertilizer obtained; and also by providing a renewable energy source (biogas), which may help reduce current propane dependence and cost, or even the lack of electricity over a longer term.
The start-up of the process using as inoculum a mixture of temperature adapted pig manure and sewage sludge (stored in anoxic conditions at environmental temperatures for a month), together with fresh rumen from a slaughterhouse, resulted in immediate biogas production, with production rates (5.4 L biogas day−1) and yield (66.1 L biogas kg VS−1), within the range of those reported in the literature. However, methane content in biogas (∼20%) was remarkably low even after 80 days, indicating that a longer adaptation period, of at least 3 months, is necessary to ensure initial methanogenic population development at ambient temperatures.
The use of urine instead of water for pig manure dilution proved feasible, since biogas production (7.7 L biogas day−1) and yield (76.6 L biogas kg VS−1) at ambient temperatures and with relatively high solids content in manure (∼8% TS/6% VS) were similar to those obtained under similar conditions, but using water for manure dilution, in other studies. This is a key consideration when assessing the viability of real scale implementation of anaerobic digestion in Ventanilla, due to the extreme scarcity of water in the area.
Conclusions
The results of this work reveal the potential of anaerobic digestion of pig manure as an alternative to improve living conditions in Parque Porcino de Ventanilla: first of all, by substituting current manure dumping and incineration, thus reducing environmental pollution and hazards to human health, as well as allowing the recycling of this organic material through land application of the organic fertilizer obtained; and also by providing a renewable energy source (biogas), which may help reduce current propane dependence and cost, or even the lack of electricity over a longer term.
The start-up of the process using as inoculum a mixture of temperature adapted pig manure and sewage sludge (stored in anoxic conditions at environmental temperatures for a month), together with fresh rumen from a slaughterhouse, resulted in immediate biogas production, with production rates (5.4 L biogas day−1) and yield (66.1 L biogas kg VS−1), within the range of those reported in the literature. However, methane content in biogas (∼20%) was remarkably low even after 80 days, indicating that a longer adaptation period, of at least 3 months, is necessary to ensure initial methanogenic population development at ambient temperatures.
The use of urine instead of water for pig manure dilution proved feasible, since biogas production (7.7 L biogas day−1) and yield (76.6 L biogas kg VS−1) at ambient temperatures and with relatively high solids content in manure (∼8% TS/6% VS) were similar to those obtained under similar conditions, but using water for manure dilution, in other studies. This is a key consideration when assessing the viability of real scale implementation of anaerobic digestion in Ventanilla, due to the extreme scarcity of water in the area.
การแปล กรุณารอสักครู่..
