**2. Absorption process simulation**

This process is a "traditional" dehydration process based on triethylene glycol (TEG). The goal is to reduce the amount of water in natural gas using TEG, which is used as an extraction solvent. This process is necessary to avoid the formation of hydrates at low temperatures or corrosion problems due to the presence of carbon dioxide or hydrogen sulfide which are regularly found in natural gas.

The effectiveness of the gas dehydration method is measured by the water content in the dry product gas. Most gas sale contracts specify the maximum amount of water vapor allowed in the gas. The maximum amount of water vapor is estimated at 7 lbs./MMscf. Standard gas specifications also limit the water dew point to �10°C to ensure flow in export pipelines on the seabed [6]. Distribution specifications depend on the geographic region in which they are applied. For example, in Russia, the dew point temperature of the water during winter is �20°C, and during summer it is �14°C for natural gas at a pressure between 4 and 7 MPa [7].

The composition, temperature, and pressure of the Yamburg X-field gas were selected to simulate wet gas dehydration in Unisim Design R460.

**Table 1** represents the composition of the gas of the X field and **Table 2** represents the parameters of the gas and the triethylene glycol.

The moisture content of the gas is 600 mg/m<sup>3</sup> , this value exceeds the specification (100 mg/m3 ), so the gas must be recycled.

We accept the multiplicity of the TEG, equal to 1.500 m<sup>3</sup> /h, the mass percentage is 99.7%.

The mass flow rate of moisture in the gas is calculated by the formula:

$$\mathbf{Qm.} = \mathbf{Wi} \times \mathbf{V} \tag{1}$$

where V is the volumetric amount of hydrocarbon raw materials, m<sup>3</sup> /h. Wi—initial moisture content.

In most installations, the rate of the TEG absorbent is 1–10 m<sup>3</sup> /h and depends on the degree of gas purification [8].
