**2. Carbon dioxide properties**

Carbon dioxide is formed from the combination of two elements: carbon and oxygen. It is produced from the combustion of coal or hydrocarbons. CO2 is a colorless, odorless, and non-toxic stable compound found in a gaseous state at standard conditions. In petroleum engineering application, it can be in a gas or a liquid state depending on the PVT conditions. **Table 1** gives the main properties of carbon dioxide. The phase diagram (**Figure 2**) of CO2 is

also a key data since we can inject it under different temperature and pressure conditions. The three phases are shown in this diagram, with the triple and critical point. Above the critical

/kg

is considered as a supercritical fluid.

**Property Value** Molecular weight 44 g/mol Critical temperature 31°C Critical pressure 73.77 bar Critical density 467.6 kg/m3 Triple point temperature −56.5°C Triple point pressure 5.18 bar Boiling (sublimation) point (1.013 bar) −78.5°C Critical Z factor 0.274

A Review on the Application of Enhanced Oil/Gas Recovery through CO2 Sequestration

http://dx.doi.org/10.5772/intechopen.79278

243

Density of carbon dioxide snow at freezing point 1562 kg/m3 Latent heat of vaporization (1.013 bar at sublimation point) 571.1 kJ/kg1

Vapor pressure (at 20°C) 58.5 bar Liquid density (at −20°C and 19.7 bar) 1032 kg/m3 Viscosity (at STP) 99 μPa s

Gas density 2.814 kg/m3 Gas density (according to STP) 1.976 kg/m<sup>3</sup> Specific volume (according to STP) 0.506 m3

Cp (according to STP) 0.0364 kJ/(mol K)

Cp/Cv 1.308 Viscosity (according to STP) 13.72 μPa s Thermal conductivity (according to STP) 14.65 mW/(m K) Enthalpy (according to STP) 21.34 kJ/mol Entropy (according to STP) 117.2 J mol/K

*Note*: STP stands for standard temperature and pressure, which are 0°C and 1.013 bar.

(according to STP) 0.0278 kJ/(mol K)

point, the CO2

**Table 1.** Carbon dioxide properties [3].

Solid phase

Liquid phase

Cv

Characteristics of CO2

gas phase


**Table 1.** Carbon dioxide properties [3].

resulted from the displacement energy naturally existing in a reservoir; the driving energy may be derived from the expansion of the gas cap or an active aquifer, from the liberation and expansion of dissolved gas, from gravity drainage, or from a combination of all these mechanisms. Secondary recovery, the second stage of operations, usually was implemented after primary recovery declined. Traditional secondary production processes are gas injection, water flooding, or water alternative gas injection (WAG). Tertiary recovery or enhanced oil recovery (EOR) is a term used to describe a set of processes intended to increase the production of oil beyond what could normally be extracted when using conventional oil production techniques, while traditional oil production (primary and secondary stage) can recover up to 35–45% of the original oil in place (OOIP). The application of an EOR technique is typically performed toward what is normally perceived to be the end of the life of an oil field, and

, CO2

Carbon dioxide is formed from the combination of two elements: carbon and oxygen. It is

non-toxic stable compound found in a gaseous state at standard conditions. In petroleum engineering application, it can be in a gas or a liquid state depending on the PVT conditions. **Table 1** gives the main properties of carbon dioxide. The phase diagram (**Figure 2**) of CO2

), chemicals, and/or thermal energy to

is a colorless, odorless, and

is

tertiary production used miscible gases (e.g., CH4

produced from the combustion of coal or hydrocarbons. CO2

displace additional oil (5–15%).

**Figure 1.** Oil recovery stages [1].

242 Carbon Dioxide Chemistry, Capture and Oil Recovery

**2. Carbon dioxide properties**

also a key data since we can inject it under different temperature and pressure conditions. The three phases are shown in this diagram, with the triple and critical point. Above the critical point, the CO2 is considered as a supercritical fluid.

**Figure 2.** CO2 phase diagram [2].
