Producción de gas metano y caracterización de la calidad del lixiviado proveniente de una biocelda para el manejo de residuos sólidos

Abstract

The disposal of solid waste in conventional landfills generates greenhouse gas emissions, produces leachate, and is characterized by inefficient energy use. An alternative to landfills is the implementation of biocells with leachate recirculation, whose system allows for rapid biodegradation and stabilization of organic matter, as well as a higher rate of methane gas generation, which is utilized for energy production. In this study, the waste stabilization system was implemented by operating three biocells in the laboratory for 12 weeks. Three types of organic waste were incorporated into the biocells: sludge from the Ambato Wastewater Treatment Plant, compost, and green waste. The evolution of the process is monitored by quantifying the generated methane gas and characterizing the leachate. Methane gas production was determined using a biogas collection system through displacement with a NaOH solution, which stabilized from day 21 of operation. The leachate quality was evaluated by determining parameters such as chromium, cadmium, ammonium, phosphate, sulfate, iron, magnesium, COD, and sulfides. The leachate characterization shows a concentration of phosphorus and nitrogen within typical ranges for biocell leachate, with a neutral or slightly basic pH. Additionally, a significant decrease in the concentration of cadmium, total chromium, hexavalent chromium, ammonium, iron, magnesium, and sulfides was observed as the biocell operation progressed.