Session 2 Stage in Field Development Hydrocarbon Classification

Session 2 Stage in Field Development

Hydrocarbon Classification and Oil Reserves q Hydrocarbon Classification ØLiquid Hydrocarbons Crude Oil, N Natural Gas Liquids, NGL Condensate, CL Gasoline, CLg Liquefied Petroleum Gases, CLp (LPG)

Hydrocarbon Classification and Oil Reserves Ø Natural Gas Nonassociated Gas, G Associated Gas, Ga Dissolved Gas, Gd Injected Gas, Gi

Hydrocarbon Classification and Oil Reserves Fig. 1 - Fluid Hydrocarbon Classification

Hydrocarbon Classification and Oil Reserves q Oil Reserves Classification ØRecovery possibilities ØDegree of proof ØDevelopment and producing status ØEnergy source Primary reserves Secondary reserves Tertiary reserves

Hydrocarbon Classification and Oil Reserves Fig. 2 - Oil Reserves Classification and EOR Target and Path

Producing Reserves n Oil Recovery Methods • Primary Recovery Methods • Improved Recovery Methods Conventional methods (secondary methods) n Enhanced oil recovery methods (tertiary methods) n ü from research and lab experiment, which can improve the possible reserves, ü through field pilot tests, which can increase the probable reserves, ü to proved and producing reserves when the commercial development of the reservoir under one of the EOR methods is in place.

Fig. 3 - Primary and Improved Recovery Methods

Primary Recovery Factor Water Drive RF mencapai 50% Well Head oil water RESERVOIR

Solution Gas Drive RF mencapai 15%-25% Well Head Gas terlarut oil Gas terlarut Gas terlarut RESERVOIR Gas terlarut

Gas Cap Drive RF mencapai ……. % Well Head Free Gas RESERVOIR oil

Producing Reserves n Enhanced Oil Recovery Methods ü improve sweep efficiency by reducing the mobility ratio between injected and in-place fluids, ü eliminate or reduce the capillary and interfacial forces and thus improve displacement efficiency, and ü act on both phenomenon simultaneously. • Chemical Methods • Miscible Methods • Thermal Methods

Table 1 – Methods and Enhanced Recovery

Producing Reserves n Oil Recovery Factor 5 -10% Tight oil reservoirs, slightly fractured or heavy oil reservoirs 10 -25% Oil reservoirs produced mainly by solution gas drive 25 -40% Oil reservoirs producing under partial water drive, gas injection, or gravity drainage 40 -55% Oil reservoirs produced by conventional waterflood

Producing Reserves Table 2 – Conventional and EOR Methods Efficiency (ER)