A Simple Method To Extract Fats, Oil And Grease For Biodiesel Production From Grease Trap Waste

Abstract

Fats, oil, and grease (FOG), the main composition of dewatered grease trap waste (GTW), is the major cause of sewer pipe blockage that can lead to a costly treatment for councils as well as the households. To prevent this, grease traps are required to be installed in most of the hospitality services such as restaurants as well as food processing factories. As a result, a large amount of GTW is being collected and need to be treated that can cause many problems for most of the environmental services. This study investigated a potential and simple solvent extraction method to extract FOG from GTW. The resulting FOG was then used to produce biodiesel utilizing ethanol as a reagent. GTW was collected from an environmental service in Adelaide, South Australia, while hexane (HEX), diethyl ether (DEE) and a mixture of hexane - diethyl ether (HEX-DEE) were utilized as a solvent to extract FOG. The results showed that the extraction yield was increased significantly while utilizing the solvent in the following order: DEE > HEX-DEE > HEX. A 96% extraction yield was obtained under the optimum operating condition of 1:1 DEE-GTW ratio (vol/w), 30°C, 300 rpm and 360 min. In addition, all of the solvents are recycled and can be utilised continuously two to three times for FOG extraction with approximately to 88% extraction yield.