Analysis of Air Fuel Ratio on Combustion Flames of Mixture Waste Cooking Oil and Diesel using Preheating Method

Abstract

Fossil fuels are a non-renewable energy source results in depletion of fossil fuel reserves. Utilization of used cooking oil as an alternative fuel is one solution to overcome this problem. This study objective is to design a stove fueled by waste cooking oil and determine the optimum air flow rate and fuel flow rate in combustion. This study uses the used cooking oil as the main fuel, and diesel fuel as a mixture with a mixture of 100% used cooking oil, used cooking oil 80:20, 70:30, and 60:40 to diesel fuel. Fuel valve opening variations used are ¼ open, ½ open, ¾ open, and fully open, while the variation in air flow rate used is 14.91; 19.24; 27.64; and 31.28 m/s. The fuel samples used were tested for the heating value, flash point and fire point, fuel density, and water fuel ratio (AFR) analysis and water boiling test (WBT). The results showed that used cooking oil had a heating value of 37,231.11 kJ/kg, flash point 289ºC, and fire point 305ºC. To achieve optimum AFR conditions (12-16:1) at a fuel flow rate of 2.5 mL/min (¾ valve open) and an airflow rate of 27.64 m/s, and WBT analysis with 221 mL fuel consumption requires a long time boiling water 16’23” minutes. Conversion of used cooking oil to kerosene fuel is 1 liter of used cooking oil equal to 0.3 liters of kerosene.