Product Highlights
Two standard modules (P5 and P60) with a range of gas pre-treatment options
PolaireTech’s offering consists of a standardised and modularised plant for small-scale LNG applications. The technology is based on a novel cost-effective, highly efficient, and reliable zero- refrigerant technology.
In recent years, small-scale LNG applications for peak shaving and transportation fuel have received significant attention, leading to the development of alternative LNG processes. Although conventional processes have been successfully used for large-scale applications, these processes use complex technologies, such as mixed refrigeration liquefaction and amine gas treatment, which is not commercially viable in small-scale LNG production.
PolaireTech uses a patented Zero- Refrigerant LNG (ZR-LNG) technology to reduce the capital and operating costs in small-scale LNG production, reducing the quantity of equipment required.
PolaireTech’s modular plant offers the following additional advantages over conventional process schemes:
- No refrigerant storage and transfer systems
- No make-up refrigerants required
- No additional chemicals required (zero-chemical)
- No waste aqueous steam
- A continuous process with a high range of operating conditions
- Feed gas flexibility
- Operational simplicity
- Lower power demand
- Capital cost savings
- Energy-efficient liquefaction process
- Efficient nitrogen removal
- Shorter implementation schedules
The design is based on ambient air to cool process streams, eliminating the need for cooling water. Furthermore, no hot utility, chemicals or refrigerant make-up is required. Operation in remote locations is therefore much simpler.
Process Description
Gas Receipt and Purification
Gas is received from the gas treatment plant and purified in a gas cleanup section to the required specification for producing LNG.
A range of gas pre-treatment modules is available.
Gas Compression and Expansion
Purified feed gas enters the plant in the gas compression loop. The compression loop consists of a number of compressors in stages to obtain the required pressure. The gas is then cooled and expanded to low temperature and pressure to achieve the necessary cold streams before being fed to the cold box for liquefaction.
Liquefaction
Treated, and dry natural gas from the compressors enters to cold box where it is cooled and liquefied against the cold streams from the expanders as well by the gas recycle from the LNG flash section. The return gas is recompressed in the compression loop. The cold box is a compact multi-stream heat exchanger insulated with perlite.
LNG Flash
Cold streams from the cold box are fed to the LNG flash section where the pressure is reduced and fed into the flash drum where the liquid and vapour fractions are separated. The methane-rich gas (flash gas) from the flash drum is then recycled back into the Liquefaction Section to cool the incoming purified gas. The liquid LNG from the flash drum is then transferred to storage.
