Numerous studies have been performed on the generation of several silicon-based engineering materials that often have used chemical materials that have high risks for health and the safety of the environment. Generally, in the synthesis of Nano-silica, tetramethoxysilane, tetraethoxysilane, and tetraethyl orthosilicate (TEOS) are used as precursor materials; however, these materials are toxic and expensive for the production of Nano-silica. This paper presents an environmentally friendly short method (EFSM) with high efficiency for the synthesis of amorphous silica oxide Nanoparticles by using agricultural waste called rice husks (RHs). Use of the EFSM method as an alternative to the chemical methods would have the advantages of fast and simple operation, controllability, great pureness of the Nanoparticles, and low manufacturing cost. A Nanoparticles (NPs) evaluation was conducted with energy-dispersive spectroscopy (EDS), field emission scanning electron microscope (FESEM) and X-ray fluorescence (XRF). By applying the EFSM method, non-toxic amorphous silica nanoparticles with a purity of 94.5% and particle size less than 100 nm was synthesized without using any chemical material.

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Drilling fluid is being used to facilitate drilling operation from the surface to a target formation. Due to the complexity of well geometry in directional drilling operations and high torque and drag forces, minimizing the coefficient of friction (CoF) is important. Excessive torque and axial drag cause mechanical erosion on the drill string, which ultimately leads to fatigue, wash out and twist off. Field data for 9 wells in one of the Iranian oilfields showed that slide drilling was practically impossible beyond 4000 m due to the unexpected high torque and drag during directional drilling despite the presence of liquid lubricants in drilling fluid at concentrations up to 5 vol% as per drilling program. Based on the results, the primary source of torque and drag in the wells with proper hole conditioning is sliding friction. Using different types of lubricant in drilling fluid system is the most practical methods to reduce the drag force (sliding friction) caused by the contact between drillstring and well casing or borehole. This paper investigates the effect of solid and liquid lubricants on the CoF in laboratory and field applications. Based on the successful implementation, a specific instruction was designed for the use of glass bead as a solid lubricant in drilling fluid to reduce the CoF. Cost estimation indicates that compared to the liquid lubricants, solid lubricants can reduce drilling fluid costs significantly. Moreover, based on Experimental results, no more than 5-6 percent of liquid lubricants can be used to reduce friction coefficient. This limitation, along with the issue of lubrication regimes, leads us to use solid lubricants. Laboratory and field test results showed that addition of glass bead as a solid lubricant can improve the performance of water-based drilling fluids as evidenced by improvement in ROP up to 240% (average ROP: 160%).