การศึกษาศักยภาพการใช้น้ำมันปาล์มดิบเป็นเชื้อเพลิงสำหรับการเผาไหม้โดยตรง

Abstract

Currently, Thailand supports more alternative energy use especially, biomass energy. The advantages of using biomass energy besides being a renewable energy that releases less emissions to the environment. It is also another way to help farmers when there is an oversupply situation. For example, southern Thailand, where most of the palm plantations in the country, were experiencing oversupply during year 2018-2019. Normally, most palm oil will be purified or added with other substances before being processed into other products such as biodiesel, palm oil for consumption, cosmetics, etc., but when there is an oversupply situation, demand does not match supply. This causes palm growers to face the problem of low product prices. So, accelerating the release of palm oil productions by using it as a fuel for direct combustion, such as boilers, fuel in power plants is a method that can help solve oversupply situation faster compared to other methods. This research aims to study the potential of using crude palm oil as an alternative liquid fuel to replace diesel or fuel oil in industries. Starting with the case of using refined palm oil as fuel as a guideline for studying and developing the use of crude palm oil in the future. For an experimental study, palm oil is preheated to 140, 160 and 180 °C and then sprayed with air with pressure 20, 40 and 60 psi through a 2 mm diameter nozzle into the combustion chamber. Inside the combustion chamber, there is an installation of an LPG pilot flame. When the system reaches a steady state, the flame profile is captured with a digital camera and the composition of the combustion exhaust gases is analyzed with a Testo 350 gas analyzer. The results were compared with a numerical study of combustion under the same conditions using the computer program ANSYS Fluent by designing the combustion chamber in an axisymmetric 2D with species transport model. The results show that higher preheat temperature and pressure accelerated combustion reactions and lead to high temperature, large size and long flame penetration. For emissions released from combustion, CO and NOx tend to decrease when preheat temperature and air pressure are high.