Banca de DEFESA: MIZRAIM BESSA TEIXEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MIZRAIM BESSA TEIXEIRA
DATE: 13/03/2021
TIME: 14:30
LOCAL: remotamente pelo Google Meet
TITLE:

Rice husk ash influence in cement slurries for early stages offshore well cementing, an economic and sustainable alternative.

 

KEY WORDS:

cementing, offshore, low temperature, sustainable.

PAGES: 50
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUMMARY:

The use of rice husk ash (RHA) in cementitious formulations has been widely studied in the literature in recent years. There are several applications for this by-product of the food industry. Some examples are the use of ash as a fertilizer, as a source of amorphous silica, as a source of pozzolanically active biomass and in the formulation of cement pastes for onshore oil wells, from medium to high temperature (50-200 ° C). However, little has been investigated about the use of RHA for low temperature systems, as is the case with the cementation processes of the initial phases of offshore wells, which generally occur at temperatures around 3-5 ° C. This study aims to analyze the influence of the addition of RHA in cement matrices destined for offshore operations that occur between 3-5 ° C. Cement pastes with a fixed density of 13.5 lb / gal (1.62 g / cm³), containing RHA (0%; 10%; 20%; 30%; 40% and 50%), were prepared and technological tests conducted (Resistance to Compression, UCA, Thickening Time, Stability, Rheology) in order to verify the feasibility of using ash for low temperature oil wells. The tests showed that the use of ash provided hydrated product with 96.8% of the standard paste resistence (Portland Cement  + 2% bentonite), as well as improving the stability and rheology of the paste in relation to those without addition. The addition of 50% ash reduced the percentage of free water in the paste by 5.6%, compared to 0% RHA. The formulation containing 50% RHA showed adequate resistance gain profile, with a pumpability time of 23h (50Bc). The stability test proved that the addition of RHA increases the stability of the paste, reducing the top drawn and avoiding decantation of the paste. RHA is a sustainable alternative for applications in low temperature environments, such as early stages of marine oil wells, considerably reducing cement consumption (15% by weight in relation to standard paste), thus contributing to the reduction in emissions of CO2 in the atmosphere due to cement production. Finally, RHA proved to be extremely economically viable. Compared to standard formulation, the use of 50% ash reduced the cost of the barrel by 23.7%, which represents savings of U$ 7.49 for each barrel (bbl).

BANKING MEMBERS:
Presidente - 1804366 - JÚLIO CÉZAR DE OLIVEIRA FREITAS
Externo à Instituição - LECH WALESA OLIVEIRA SOARES - IFPB
Externo ao Programa - 1995142 - RODRIGO CÉSAR SANTIAGO