Pyrolysis of Waste Lube Oil to Obtain Liquid Fuels

Authors

Pretell, Victor

Lazarte, Cesar

Sanchez, Hugo

Lujan, Cesar

Ramos, Williams

Abstract

Waste lube oils (WLO) are discarded as they do not fulfill their lubricating function. In Peru, as of 2019, an offer of 23,922 MT of lubricating oils for light vehicles was estimated, of which 11,961 MT are WLO. The recycling of WLO is important to protect the environment, its treatment has several benefits such as being an energy source, avoiding oil consumption, and protecting the environment from toxic substances. A recycling alternative is a pyrolysis as it is an economical and ecologically friendly process. The yield and quality of liquid fuels obtained by carrying out non-catalytic and catalytic pyrolysis with kaolin as catalyst was investigated, the effect of temperature and the catalyst: WLO ratio on the yields of liquid fractions were evaluated. In non-catalytic pyrolysis, the conditions that yield a quality product like diesel are, pressure of 68 kPa, the temperature of 480 °C, and 300 rpm for the agitator. The yield of liquid products is 90%, solids 3.9%, and gases 6.9%. The liquid product obtained at that temperature is closer to meeting the Peruvian diesel specification. The flashpoint of the pyrolytic liquid at this temperature is 58 °C and meets the diesel specification. The pyrolytic liquid at this temperature shows a better quality with respect to its flashpoint, but the volumetric yield of the diesel-type middle distillate fraction decreases. In both cases, the pyrolysis product requires further treatment to be used as a commercial fuel.