Modelización de la producción de Biogás en vertederos controlados

Resumen

Amongst all the different alternatives for the elimination or treatment of MSW (Municipal Solid Waste), sanitary landfilling is probably the one that is most widely employed to date, due to its economic advantages. With the coming into effect of the Spanish Containers and Packaging Law, alongside that of the Council Directive 1999 / 31 / CE , concerning waste disposal, this situation will be substantially modified. At the same time, the application of said Directive will influence the amount of biogas generated in landfllls. The present research work is a study of the influence that the aforementioned Directive will have on the production of biogas in a sanitary landfill which currently disposes of around 400,000 Tm / year of MSW, 52% of which is easily biodegradable organic matter. The model proposed by Marticorena was appied and the kinetic parameters, MPO and d, were experimentally obtained by means of a pilot-plant study of MSW anaerobic degradation, the values employed being 173 Nm3 of biogas / Tm of the organic fraction of MSW for MPO, and 3 years for d. The results obtained in the model are compared with those obtained experimentally at the COGERSA landfill, Asturias, Spain. Twenty wells were chosen to analyse the production of biogas, giving an overall average yield of 70%. In 1999,around 4,100 m3 / h of biogas were extracted at the COGERSA landfill. Application of the model gave an estimation for 1999 of an average production of 5,369 m3 / h, giving a maximum yield in the extraction of biogas of around 75%. The difference between the two average yields obtained may be due to the fact that the model only takes into account the easily biodegradable organic fraction, whilst in the landfill, given that more time has passed, other substances with a longer period of degradation, such as paper and cardboard, may also be degraded.