SYNTHESIS OF LIGNIN-BASED BIOADTIVE FOR APPLICATION IN CEMENTING OIL WELLS
Lignocellulosic biomass; lignin; natural additives; cementing; oil wells.
The cementing stage plays a crucial role in the construction of oil wells, as it is directly linked to their integrity and durability. A slurry used for this purpose typically consists of water, Portland cement, and additives. Additives are essential materials to adjust the physical and chemical properties of the slurry, making it suitable for the unique temperature and pressure conditions encountered in wells. Additives can be synthesized from various inorganic and natural compounds; an example is lignin, a polymer present in lignocellulosic biomass that has low commercial value. However, through structural modifications, lignin can acquire exceptional properties, making it highly valuable and suitable for various industrial applications. Thus, in addition to benefiting the oil and gas industry, using lignin as a raw material for synthesizing additives for well cementing is a way to add value to lignocellulosic biomass. Therefore, this study aims to develop a bio-additive from lignin extracted from green coconut biomass through oxidative modification with hydrogen peroxide for application in cement pastes for oil well cementing. To achieve this, lignin from green coconut biomass will be extracted through alkaline pretreatment, and its structural modification will be carried out through the oxidation process. After the synthesis process, both unmodified lignin (UL) and oxidized lignin (OL) will be characterized using Zeta potential, Fourier-transform infrared spectroscopy (FTIR), quantification of phenolic compounds, and thermogravimetric analysis (TGA/DTG). UL and OL will undergo validation steps as dispersant and retarder additives, with heated rheology tests and thickening time tests. After validation, to better evaluate the behavior of the synthesized additive and compare it with a commercial additive, a simulation of primary cementing for a 1000 m deep well with a geothermal gradient of 1.7 °F/100 feet will be conducted. The cement pastes will be characterized through rheology tests, static filtration, thickening time, and ultrasonic cement analyzer testing (UCA method).