Analyzing the Effect of Green Synthesized Bio-Based ZnO Nanoparticles on Rheological Properties of Water-Based Drilling Fluid

Green chemistry is new leading approach used for bio-synthesis of metal nanoparticles that ultimately produce an eco-friendly, less-toxic, and non-hazardous nanoparticles. Plants are among available organisms (biological systems) that have been widely investigated by recent researchers for the production of nanoparticle, due to their ability to produce more stable nanoparticles with faster synthesis rate. Zinc oxide (ZnO) nanoparticles possess stable physical and chemical properties along with being non-toxic and cheaper material and hence, it is good candidate to be bio-synthesized and applied as drilling fluid additive. Because, the biodegradability of drilling fluid and the long-term effect of discharged wetted cuttings are becoming global issues with arisen environmental concerns. ZnO nanoparticles were produced chemically by reacting zinc chloride and celery leaf extract at room temperature and precipitated via NaOH solution. The effect of different concentrations of the synthesized ZnO nanoparticles were tested on the rheological properties of water-based mud. Results showed overall improvement of the rheological properties of drilling fluid. Apparent viscosity (AV), plastic viscosity (PV) and yield point (YP) decreased as ZnO nanoparticles concentrations increased. The YP/PV ratio increased with increased ZnO nanoparticles concentrations indicating improved lifting capacity of the mud. Furthermore, the gel strength of the mud was improved with increased concentrations of the synthesized nanoparticles which enhanced drill cuttings suspension when mud circulation is ceased. Lastly, the nanoparticles acted as thinning agent useful in times when drilling into shallow unconsolidated or shale formations that usually increases the plastic viscosity of drilling fluid at constant mud weight.