Banca de QUALIFICAÇÃO: RAPHAEL RIBEIRO DA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : RAPHAEL RIBEIRO DA SILVA
DATE: 29/07/2025
TIME: 14:00
LOCAL: LABCIM
TITLE:

Development of Rock-based Geopolymers for Oilwell Cementing Applications – Utilizing Brazilian Rock Precursor

KEY WORDS:

Geopolymer; P&A operation; Well-cementing; Rock-based precursor; Low CO2

PAGES: 30
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

One-part geopolymers, often referred to as "Just-add-water" systems, represent a promising advancement in the field of sustainable materials for oilwell applications by simplifying the activation process of alkali-activated binders. With Portland cement production responsible for approximately 8% of global CO₂ emissions—amounting to over 4 billion tons annually—geopolymers offer a lower-carbon alternative by utilizing industrial by-products and reducing reliance on energy-intensive clinker production. This project focuses on developing and characterizing one-part rock-based geopolymer slurries using Brazilian rock precursors for well construction and plugging and abandonment (P&A) applications. A series of geopolymer formulations is studied, with a special focus on developing the material's mechanical strength. The study presents the fluid-state and solid-state properties of these geopolymers, as well as X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), to understand the microstructure of the precursors and the reaction level. The effect of temperature and pressure on the development of compressive strength was investigated. By altering these parameters, the study aimed to understand the impact of different environmental conditions on the strength development of the geopolymer material. Technological tests were conducted following API RP 10B-2. Compressive strength tests were conducted to determine early strength development and thickening time. Post-curing, Rietveld refinement through XRD was performed to examine microstructure and reactivity. Finally, fluid-state properties were also assessed, including thickening time and viscosity. The final product has a dense structure, and its long-term performance will require evaluation to determine its sealing capability and volume change as a barrier material. The research demonstrates the potential of rock-based geopolymers for well cementing and well abandonment applications using a Brazilian rock precursor.

COMMITTEE MEMBERS:
Presidente - 1979301 - RENATA MARTINS BRAGA
Externa ao Programa - 2621720 - ANA CECILIA VIEIRA DA NOBREGA - UFRNExterno ao Programa - 1913849 - EDGAR PERIN MORAES - UFRNExterno ao Programa - 1804366 - JÚLIO CÉZAR DE OLIVEIRA FREITAS - UFRN