Читать книгу Process Intensification and Integration for Sustainable Design - Группа авторов - Страница 28

The problem to be addressed in this work is stated as follows:

 A set of shale gas wells with anticipated profiles for variable flow rates and compositions and known, temperature, and pressure

 A known set of feedstock and product prices

It is desired to develop a systematic design and optimization approach for gas treatment plant. Although the processing steps for treating raw shale gas can vary depending on the composition of the wellhead gas, a common process flowsheet (shown by Figure 2.1) is considered. First, condensates and free water are separated. Then, acid gases (CO₂ and H₂S) are removed. Acid gas content must be lowered to permissible levels to prevent corrosion issues during additional processing and/or during pipeline transport [6]. Dehydration is then carried out to remove bound water. This water must be removed to low levels because (i) it may form hydrates with natural gas components such as methane, ethane, and carbon dioxide, and (ii) it may freeze in later processing steps. In either case, the formed solids may plug piping and separation units [6]. Next, methane (sales gas) is separated from the other NGLs. Finally the latter is fractionated into their individual components as they typically have high economic value.

Figure 2.1 Shale gas treatment process.