Synthesis of Epoxy Resin Based Geopolymer Utilizing Saudi Arabian Volcanic Ash for Primary Well Cementing Applications

Abstract

Abstract Conventional cement production possess huge environmental concerns. Which is considered globally the third largest source of CO2 emissions into the environment. This is due to the decomposition of carbonates that produce around 900 kg of CO2 for every 1000 kg of cement production. As a substituent, geopolymer cement can reduce the CO2 emissions by 80% because there is zero CO2 emissions through the geopolymer cement production. Moreover, Geopolymer cement can be prepared utilizing waste materials such as fly ash. In Saudi Arabia, we have enough volcanic ash to sustain the development of this eco-friendly cement. Furthermore, geopolymer binders show an exceptional mechanical, chemical and environmental benefits in comparison to conventional cement. In addition to geopolymer properties, liquid epoxy resins are known to increase bonding with casing; thus, increasing the wellbore integrity. In this study, we successfully developed a novel epoxy resin based geopolymer cement utilizing a Saudi Arabian volcanic ash for primary cementing applications for the oil and gas industry. This was done by adding an epoxy resin formulation to the geopolymer slurry. This novel cement shows an excellent strength and good rheological properties with a controlled setting time. The objective of this paper is to detail and explain the synthesis of this cement, geopolymer slurry preparation and epoxy resin formulation. Also, to investigate the effect of adding the epoxy resin formulation to the geopolymer slurry in terms of the final cement strength, thickening time and rheological properties as well as to detail lab testing. To prepare the epoxy resin based geopolymer, the volcanic ash particles were activated first by a mixture of NaOH, sodium silicate and water. Then, an epoxy resin formulation was added to the geopolymer slurry that contains an epoxy resin along with a curing agent. The amount of the epoxy resin formulation was varied in order to study the effect of adding the epoxy resin into the geopolymer slurry in terms of the final cement's setting time and compressive strength. This was done to develop a cement with excellent strength and controlled setting to assure a right cement placement. In addition, the chemical conditions were evaluated to simulate a variety of downhole conditions to prove the effectiveness of this novel geopolymer composition as a cement for primary cementing applications. The lab testing includes gelling time and compressive strength measurements as well as a chemical analysis of the Saudi Arabian volcanic ash.