ShareICR2011 highlights: possibilities for micro-scale natural gas liquefaction
Due to increasing energy demand, interest in micro-scale natural gas liquefaction plants for the exploitation of stranded wells is growing. At ICR2011, a team from Universita Politecnica delle Marche, Italy, presented a paper describing and comparing possible applications.
Due to increasing energy demand, interest in micro-scale natural gas liquefaction plants for the exploitation of stranded wells is growing.
At ICR2011, a team from Universita Politecnica delle Marche, Italy, presented a paper (1) describing and comparing possible applications. It focused on the technical and economic analysis of different liquefaction technologies and cycles (Linde, Claude and reverse-Brayton cycles) and gave an overview of competing technologies (Gas-to-Liquid, Gas-to-Hydrate, Compressed Natural Gas and power generation).
Small-scale natural gas liquefaction plants could make interesting and feasible on-site applications for the recovery of methane from various sources such as landfills, stranded wells and boil-off from LNG tanks. The feasibility of such plants depends on several factors such as reserve capacity, size and distance from the market making them potential niche applications, with a daily production rate of less than 60 000 litres of LNG. Thanks to a “Figure of merit” (FOM), the ratio between the theoretical minimum work required to liquefy a unit mass of gas and the actual work requirement of a system, it was possible to assess how closely a system approached ideal operation. Among the 3 considered cycles, the Claude cycle had the highest efficiency (FOM = 0.28) and the Linde cycle the lowest (FOM = 0.14), but was not far behind the Brayton-reverse cycle (FOM = 0.15), which is safer for smaller applications.
However, the Linde cycle has the lowest cost. Economic feasibility requires gas prices under USD 0.095/kg and liquefaction prices under USD 0.145/kg. Even though some competing technologies, particularly gas-to-hydrate and Compressed Natural Gas (CNG) seem interesting at such low scales, LNG could be a good option where the market is sufficiently close and accessible.
(1) Micro-Scale Natural Gas Liquefaction Plants, Arteconi et al.
At ICR2011, a team from Universita Politecnica delle Marche, Italy, presented a paper (1) describing and comparing possible applications. It focused on the technical and economic analysis of different liquefaction technologies and cycles (Linde, Claude and reverse-Brayton cycles) and gave an overview of competing technologies (Gas-to-Liquid, Gas-to-Hydrate, Compressed Natural Gas and power generation).
Small-scale natural gas liquefaction plants could make interesting and feasible on-site applications for the recovery of methane from various sources such as landfills, stranded wells and boil-off from LNG tanks. The feasibility of such plants depends on several factors such as reserve capacity, size and distance from the market making them potential niche applications, with a daily production rate of less than 60 000 litres of LNG. Thanks to a “Figure of merit” (FOM), the ratio between the theoretical minimum work required to liquefy a unit mass of gas and the actual work requirement of a system, it was possible to assess how closely a system approached ideal operation. Among the 3 considered cycles, the Claude cycle had the highest efficiency (FOM = 0.28) and the Linde cycle the lowest (FOM = 0.14), but was not far behind the Brayton-reverse cycle (FOM = 0.15), which is safer for smaller applications.
However, the Linde cycle has the lowest cost. Economic feasibility requires gas prices under USD 0.095/kg and liquefaction prices under USD 0.145/kg. Even though some competing technologies, particularly gas-to-hydrate and Compressed Natural Gas (CNG) seem interesting at such low scales, LNG could be a good option where the market is sufficiently close and accessible.
(1) Micro-Scale Natural Gas Liquefaction Plants, Arteconi et al.