masterThesis
Avaliação crítica de cenários de abandono de poços petrolíferos onshore do nordeste brasileiro
Fecha
2021-04-29Registro en:
BRAGA, Igor Pires de Melo. Avaliação crítica de cenários de abandono de poços petrolíferos onshore do nordeste brasileiro. 2021. 117f. Dissertação (Mestrado em Ciência e Engenharia de Petróleo) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2021.
Autor
Braga, Igor Pires de Melo
Resumen
Oil and gas production dates back to the end of the 19th century, with systematic
commercial production starting in the second half of the 20th century, especially with
the creation of Petrobras. Thus, thousands of oil wells were drilled in the 1950s. The
consequence of this is that these wells are many over 50 years old, and can reach 70
years old, to obtain wells with mechanical and hydraulic integrity problems. Northeast
of Brazil has thousands of non-productive oil and gas wells may that be caused by low
production, maintenance problems, companies decisions. Many are closed with no
observance to the recent plug and abandonment rules of the SGIP (Well Integrity
Management System) brought by Regulation ANP 46/2016. So it has been with the main
fields of North and Northeastern areas of Brazil. Resolution 46/2016 from ANP controls
the general procedures for stablishing a Well Integrity Management System. Thus the
new regulation marks the positivation of how to abandon an oil and gas well, always
seeking the north of well integrity, aiming the security to the people and to the
environment. Then, the non-desirable hydrocarbons flows to the surface or between
different zones (formations) will generate strong accountability, at present, for the field
operators since plug and abandonment modern regulations are based on double solidary
sets of barriers (CSBs) that aim to make the well as or more intact than virgin formations
/ reservoirs. Based on the above, this work has as main objective to present a diagnosis
of the current level of integrity risk that thousands of wells in the northeast of Brazil can
represent for the onshore environment, according to the method given by the Brazilian
Petroleum Institute, characterizing the actions that are necessary to make them conform
in terms of abandonments. To reach it, this paper presents the recent rules for onshore
abandonments in Brazil, also arising from the best international practices in the subject.
A parallel is made between the old ANP decrees of 1997 and 2002, analyzing the main
changes in the ways of conceiving abandonment interventions, reflecting in the
professionalization of practices, operational discipline, safety, and especially the search
for economics. The time and cost to abandon a well where mechanical integrity has been
sought throughout the entire life cycle is considerably smaller.