SVIBOR - Project code: 2-16-230

MINISTRY OF SCIENCE AND TECHNOLOGY

Strossmayerov trg 4, HR - 10000 ZAGREB
tel.: +385 1 459 44 44, fax: +385 1 459 44 69
E-mail: ured@znanost.hr

SVIBOR

SVIBOR - Collecting Data on Projects in Croatia

Project code: 2-16-230


ENHANCED HYDROCARBON RECOVERY BY GAS INJECTION PROCESSES


Main researcher: GORIČNIK, BOGDAN (72195)


Assistants
Type of research: developmental
Duration from: 04/30/91. to 04/30/94.
Papers on project (total): 14
Institution name: Rudarsko geološko naftni fakultet, Zagreb (195)
Department/Institute: Reservoir Engineenring Department
Address: 41000 ZAGREB, Pierottijeva 6
Communication
Summary: The following methods of oil recovery (EOR) by gas injection were studied: (1) Mechanism and efficiency of carbon dioxide (CO2) process, which included (1a) examination of miscibility zone formation (external or in situ) and its influence on oil recovery; (1b) mathematical modeling of oil-CO2 mixture phase behavior by Peng-Robinson EOS regression to experimental PVT-data; (1c) examination of injection CO2 mobility control in relation to fluid flow characteristics and oil recovery. An apparatus for CO2 foam generation, mobility and oil recovery measurements was constructed. Basic relations between foam quality, mobility and produced oil were determined; (1d) Corrosion process in CO2-environment was investigated. Corrosion rates of oilwell materials were measured and predominant corrosion mechanism at different p,T-conditions as well as water chemical composition were determined.Degree of protection of the materials by corrosion inhibitors was determined. The nature of the corrosion process of austenitic steel welds was also examined. (2) Process of gas (natural gas/methane,carbon dioxide,nitrogen) injection into gas condensate field was investigated. PVT-relations of condensate-injection gas mixtures were measured and degree of retrograde vaporization determined. Phase diagrams and corresponding mathematical models (PR EOS) were made. Simulation of the retrograde vaporization dynamic process was performed in order to obtain process parameters. (3) Methane gas injection into partially depleted oil reservoir was investigated. Based on experimental reservoir oil PVT-data, fluid phase behavior model was made. Extensive simulations of cyclic process of gas injection were made. Produced gas injection composition was determined for different schemes of maximum gas pressure. Process of oil production during pressure maintenance was also examined. Comparative analysis of the results favors gas storage/cycling scheme.

Keywords: enhanced recovery,hydrocarbons,carbon dioxide,retrograde vaporization,gas injection,mobility control,corrosion,cycling

Research goals: (1) Development of improved and/or new methods of experimental oil displacement simulation tests, (2) Measurement of PVT-behavior of oil/condensate-injection gas mixtures in conjunction with enhanced oil recovery predictions, (3) Mathematical modelling of hydrocarbon fluid-injection gas mixtures, based on contemporary equations-of-state, with subsequent use of the models in fieldwide simulators, (4) Determination of corrosion mechanism of oilwell materials in CO2 environment, based on corrosion rate measurements under realistic p,T-conditions. In addition to more fundamental contributions in understanding the nature of phase transitions and thermodynamics of complex natural hydrocarbon mixtures, the results of the research project are expected to furnish important data needed for feasibility study of the EOR processes investigated.
Other information about the project.
MZT Croatian language SVIBOR Alphabetic list Sorted on project code Sorted on institutions Search help
Ministry of
Science and
Technology		 Croatian
language		 Svibor
homepage		 Alphabetic
list		 Sorted on
project code		 Sorted on
institutions		 Search Help
Last update: 10/09/95
Information: svibor@znanost.hr