Cluster LNG: A Solution for Southeast Asia Gas Demands

摘要

Conventional LNG with ambient pressure has been known as efficient means of gas transportation by reducing the volume to 1/600. However, since end-users always need as gas form not LNG itself, LNG may be regarded as interim means of transportation, and at the same time, LNG production and storage with different pressure conditions are also acceptable provided they meet cost competitiveness. Increased pressure Cluster LNG has been developed as an economic solution for small and medium scale natural gas chains. Small and medium scale LNG plants could not be practically developed due to difficulties in unit price competition with large scale LNG plants. Considered small and medium scale gas markets are increasing in Southeast Asia, cost-effective solution for the LNG chain is very much demanding. The current LNG infrastructures with large volume facilities may not be suitable for the new diverse requirements from scattered small and medium gas fields and consumers. DSME has developed innovative LNG solution, called Cluster LNG, which may bring substantial changes from the traditional LNG chain. To implement the cost-effective integrated LNG system, technologies in each sector of LNG chain, production, transportation, and regasification have been developed. In the Cluster LNG, natural gas is liquefied at increased pressure instead of ambient pressure to have overall efficiency. LNG liquefaction at the increased pressure requires less power in the refrigeration system with relatively higher liquefaction temperature and adoption of more efficient refrigerant for the temperature range, and it also simplifies the gas treatment system with CO2 tolerant liquefaction characteristics. The increased pressure LNG containment system, which would be key factor for overall economics, has been developed with innovative hybrid design against cryogenic temperature and high pressure to achieve the cost-effectiveness task. In order to verify the cluster LNG liquefaction, regasification process, loading and unloading operation, and diverse safety requirements, a bench scale pilot plant was constructed and extensive operation tests have been carried out. The operation results show outstanding liquefaction performance compared with conventional LNG plants. Now the developed system of the Cluster LNG is ready for commercialization. The Cluster LNG is ideal for small and medium LNG production, transportation, and consumption with the inherent cost-effectiveness and flexibility. The transportation of the Cluster LNG can be done by ordinary bulk carriers or containerships retrofitted for the Cluster LNG containment system instead of purpose built LNG carriers. Typical size of Cluster LNG containment system is 200 ~ 500 m3. Hence, the storage tanks for production, transportation, and regasification sites can be implemented with 10 ~ 100 clusters of pre-fabricated cylinders. The Cluster LNG will provide flexible business model by quick decision and execution with lower project cost. The competitive Cluster LNG system will activate stranded gas field developments around world, which ultimately would contribute to existing and developing gas markets. Especially, the Cluster LNG may provide gas supply solutions for smaller demand markets such as diesel engine driven power plants in remote islands and utility gas distribution networks to many small and medium provinces in Southeast Asia.