As the world continues to shift towards decarbonization in chemical production, and strong market demand drives the transition to carbon-free energies, ammonia’s role in the green energy economy continues to expand. In Black & Veatch's recently release Hybrid LNG & Ammonia Infrastructure: Key to a Green Economy eBook, we explore cost saving design solutions to prepare for a transition to carbon-free energy.
From that eBook, this section discusses how the LNG import facility can be designed to be ammonia-ready with minimum required modification.
Table 6 compares LNG and ammonia governing design parameters and their impact on the facility design.
The following items need to be addressed in the initial design of an LNG import facility in order to import and store ammonia in the future.
The LNG storage tank requires additional design consideration to be used for ammonia which is discussed in Designing Ammonia-Ready LNG Storage Tanks.
Boil-off Gas (BOG) System
The LNG regasification facility requires much higher BOG system capacity due to greater vaporization rate. The alternative design provides BOG system and refrigeration in greater number of trains with lower capacity for each which increase the flexibility of the facility in operation also operates the compressors on the best operating points. Greater BOG rate for LNG requires the LNG/ammonia design flare stack to operate at lower BOG rate as needed for ammonia import and storage facility.
The liquid LNG transfer pumps (submerged pump and HP pumps) need to be replaced for ammonia service. The LNG pumps are designed for very low temperature which are not suitable for ammonia. The proper piping and layout requirements for ammonia pump need to be considered for required future modification.
Piping supports need to be designed based on ammonia due to higher density.
Instrument and Safety Devices
Instrument and safety devices need to be designed for the governing case for LNG and Ammonia services.
The LNG import facility design consideration for ammonia application requires pre-investment to minimize the cost impact on the future to convert the facility to an ammonia import facility.
Table 7 shows an overall capital expenditure (CAPEX) and pre-investment breakdown.
The pre-investment cost impact will vary based on the capacity of the facility.
The import and storage facility can be designed for LNG and ammonia services without replacing the major equipment such as the storage tank and BOG compressors.
In comparison with the LNG import facility, additional investment is required to provide the alternative reception, storage and handling of ammonia. The areas of the pre-investment include the storage tank, BOG system, piping system and flare stacks, and instrument and safety devices.
About the Author
Mehran Ghasemi is a Lead Process Engineer with Black & Veatch’s Oil & Gas business. Ghasemi has more than 24 years of EPC experience in process design, simulation and operation support of upstream and midstream facilities. He is highly skilled in petrochemical and gas-to-liquid processes and technologies, gas processing facilities, onshore and offshore oil and gas production facilities, transportation pipeline design and utility systems design.