Abstract

At present, most of the light hydrocarbons (LH) separation processes that have been proposed lack the flexibility of receiving various feed components, thereby leading to an unstable operation in the liquid natural gas (LNG) receiving terminal. In response, a novel light hydrocarbons separation process (PSP) is proposed in this paper. Previously, some parameters and processes were improved upon and patented as US 7165423 B2, US 7069743 B2, and WO/2012/054729, which are respectively named as LTP, NCP, and NLP. Based on the analysis of LNG’s component statistical data in China, this paper conducts a techno-economic comparison and analysis of four kinds of LH separation process under four groups of typical feed-in components. The comparison results reveal that the system energy consumption of LTP is increased by the heater, and the higher the heavy hydrocarbon content in the feed components, the more obvious the increase in the process’s energy consumption is. NCP has the highest ethane recovery rate; however, its capital cost is too high, especially for the distillation column investment. NLP has the highest operating cost due to compressor use. Compared to the others, the PSP has the best economic benefit for specific performance: its capital cost is 18% less than that of NCP, its operating cost is 71.8% less than that of NLP, its net profit is 8% higher than that of NLP, its total investment cost is 71.7% lower than that of NLP, and its investment recovery period is the shortest. In conclusion, the PSP can be economically and efficiently used in China LNG receiving terminal, thereby generating the flexibility to receive multiple feed components.