Component analysis of fat, oil and grease in wastewater: challenges and opportunities

Abstract

The presence of fat, oil and grease can lead to blockages in sewer lines, pumps, and treatment plant operations, thereby creating health risks and environmental hazards. These deposits primarily consist of fatty acids, triglycerides and soap, among other components. These three main components are hydrophobic and insoluble in water. The composition of FOG can vary significantly depending on the source, such as food service establishments, households, or industrial processes. Several analytical methods, such as chromatographic, gravimetric, chemical and spectroscopic analysis, are used to measure different FOG components. AOAC, Gerber and APHA are the most commonly utilized standardized analytical methods for measuring FOG components. The AOAC and Gerber methods, which use gas chromatography, tend to provide more accurate results compared to other methods. This can be attributed to GC's ability to measure individual fatty acids in FOG samples by separating and quantifying each compound based on its unique chemical properties, such as volatility, polarity and molecular weight. Similarly, high-performance liquid chromatography is capable of measuring glycerides by separating and quantifying them based on their polarity and molecular weight. This article delves into the challenge of accurately measuring FOG concentrations and evaluates various FOG measurement technologies. The study also discusses the need for standardized methods for FOG measurement, highlighting the importance of understanding FOG deposits and the performance of grease interceptors.