Caribbean Open Online Course (CaribOOC) on Powering Agriculture Sustainable Energy Solutions for the Caribbean

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1 Caribbean Open Online Course (CaribOOC) on Powering Agriculture A consultancy work of GreEnergy Dominicana S.R.L., for the Powering Agriculture of the German Cooperation and the GIZ.

2 1 Project description HACIENDA LM is dedicated to raising pigs in the Commonwealth of Puerto Rico. It is the second largest pig farm on the island with a total population of 2,500 pigs (250 sows). The farm was created in 2003 and since then it managed its waste with secondary ponds and stabilization. In 2013, biodigesters were installed to promote the environmental management of the farm. Biodigesters are a cost-effective alternative for the treatment of animal manure from farms. Animal excrement is a highly contaminating waste; however, with the use of biodigesters, it can be transformed into usable and high value products. For the construction of the biodigesters at Hacienda LM, one of the two existing oxidation ponds was reused, taking advantage of the flat surfaces of the land. In this project the waste is processed in two biodigesters of different retention volumes. The first tank or pre-digester, has a capacity of 144 m3. In this container, the first phase of the decomposition of organic matter, hydrolysis, occurs. The second tank has a capacity of 2025 m3. Here the last three stages of digestion of the organic matter, acidogenesis, acetogenesis and methanogenesis are completed. Both tanks operate in a series system with a retention time of 40 days. The design considered a secondary lagoon for the storage of Biol or remaining fertilizers from the biodigestion process. The liquid fertilizer or biol is applied on the pasture lands. Hacienda LM Biodigestor

3 2 Used waste: All organic waste, including sewage waste and carcasses of pigs that died during the weaning process, is used in the process of anaerobic digestion Energy: The volume of biogas produced is 109,500 m3 per year. This gas is converted into219,000 kwh of electrical energy per year. Hacienda LM converts the biogas into electricity through a Capstone turbine that supplies each one of the ships including the food factory and the offices. This measure generates economic savings of $ 25,000 US-dollars per year for the owners. Hacienda LM Biodigestor Oxidation pond

4 3 Summary

5 4 Benefits Restoration of relations with neighboring populations affected by strong odors. Cost savings allowing an increase in the animal population of thefarm by 50%, thus a new fattening are was built. Savings in investment for fertilizers. Pollution reduction and energy saving. The reasons underlying the construction of the biodigesters are to: Restore relationships with communitiesclose to the farm by controlling the emission of odors. Avoid the construction of secondary ponds. Leverage the potential of the pastures around the plant for livestock farming. Protect the subsoil from contamination. The main changes are: The farm has a primary waste water treatment system composed of a biodigester. The company uses 70% of the biogas produced in the biodigester, in the generation of energy; the remaining 30% is burned, avoiding this way the direct methane emissions. The farm produces 219,000kWh/year of electricity. Biol from the biodigester isused as fertilizer to improve the quality of soil and grass. Waste water management is carried out by buried pipelines to eliminate odors. Generador de biogas satellite view Membrane placement

6 5 The biodigesters have represented an attractive solution for converting some of the main problems faced by the pig producer namely, the management of odors, the treatment of waste and the consumption of electric energy, into great opportunities for the development and growth of the farm. Final results 1. Reduction of air pollution 2. Reducingthecarbonfootprint and reducing the risks associated with the management of fossil fuels. 3. The farm produces 219,000k Wh/year of electric energy. 4. Thebio-fertilizersobtained are used to fertilize plantain farms and grassland usedfor livestock grazing. 5. Odor control. Company information: TERRALIMPIA EIRL La Moraleja, calle 1ra. Res. Bosque Grande. Apt. 1 Tel. (809)