a Mobile, Self-Powered Natural Gas Liquefaction Plant
Designing and building a mobile, well-fed natural gas liquefaction plant that self-powers its operations and removes impurities requires careful consideration of several key factors:
1. Well Gas Composition and Impurities:
- Analyze the well gas composition to determine the specific impurities present (e.g., CO2, H2S, Hg, water).
- Choose appropriate technologies for removing each impurity based on its concentration and desired purity level for the liquefied natural gas (LNG).
- Common impurity removal techniques include:
- Acid gas removal: Amine scrubbing for CO2 and H2S removal.
- Mercury removal: Activated carbon beds or adsorption processes.
- Dehydration: Desiccant dehydrators or glycol dehydration.
2. Liquefaction Process:
- Select a liquefaction process suitable for a mobile application. Options include:
- Cascade refrigeration: Uses multiple stages of compression and heat exchange to achieve the required cryogenic temperatures.
- Mixed refrigerant process: Employs a mixture of refrigerants with different boiling points for improved efficiency.
- Expander-based processes: Utilize turboexpanders to recover energy and improve efficiency.
3. Self-Powering System:
- Determine the power requirements of the liquefaction process and impurity removal equipment.
- Utilize the well gas as a fuel source to generate electricity.
- Options for power generation include:
- Gas turbine generators: Efficient and well-suited for mobile applications.
- Reciprocating engines: More flexible but less efficient than gas turbines.
Microturbines: Suitable for smaller scale operations.