Non-conventional Energy from Biogas Recovered from Wastewater Sludge

The energy crisis due to the depletion of fossil fuels and the negative environmental impacts they produce, require the search for more environmentally friendly energy sources. The research evaluated the electric energy obtained from biogas generated by wastewater sludge from a wastewater treatment plant (WWTP). An anaerobic biodigester was used in the process of obtaining the biogas. The wastewater was evaluated taking into account the parameters of pH, humidity and percentage of organic matter, data that also allowed determining the daily load. After 42 days, the biogas concentration was evaluated, reaching concentrations of 57.7 % methane (CH₄), 33 % carbon dioxide (CO₂) and 10 ppm hydrogen sulphide (H₂S), presenting adequate characteristics to generate electricity using a 1300 W four-stroke generator set, with a 3.0 HP, 3.0 rpm, single cylinder capacity. The mechanism consists of placing a gas mixer in the carburettor whose function is to mix the biogas and air in the correct proportions. As a result, a useful energy of 0.100 KW-h was obtained with LED bulbs of 110 W. A test was also carried out with incandescent bulbs of 100 W where a useful energy of 0.056 KW-h was obtained. It can be established that a yield of 2.421 % was reached in function to the total and useful energy registered with the LED bulbs. From the above mentioned, it is established that the biogas obtained can be a non-conventional energy source, under the concept of sustainability.