Characteristics of Gas Compositions in Giant Gas Fields of China

Abstract

By the end of 2011, altogether 48 giant gas fields with each proven reserves over 300×10 8 m 3 had been discovered in China. After studying on the main molecular compositions (methane, heavy hydrocarbon gases, nitrogen, carbon dioxide and hydrogen sulfide) of 1170 gas samples in these gas fields, it is found that: a). Alkane gases dominate the molecular compositions of the natural gases; the extremely low content of them have a tight relationship with the extremely high content of non-hydrocarbon gases; methane accounts for 60.1% of the alkane gases. b). Carbon dioxide has the average content of 4.09%; carbon dioxide with an extremely high content (>50%) is mainly distributed in Dongfang1-1, Changling and Songnan gas fields; highly concentrated CO 2 in the former one was crustal-derived while that in the latter two was mantle-derived. c). Nitrogen has an average content of 3.56% which is quite low; highly concentrated nitrogen (>20%) is mainly distributed in Hetianhe, Tazhong, Ledong22-1 and Dongfang1-1 gas fields which are organic-originated. d). Hydrogen sulfide has been detected in 12 giant gas fields, with the content of 4.91% in average; the Triassic is the most centralized zone for hydrogen sulfide while the Sichuan Basin has the largest number of sour gas fields and sour gas bearing zones; 7 sour gas fields of high H 2 S content (2% ~ 70%) are found which are resulted from the thermochemical sulfate reduction (TSR).

Raman and DFT Study of the H2S Scavenger Reaction of HET-TRZ under Simulated Contactor Tower Conditions

“…The scavenger reaction of HET-TRZ was performed in a laboratory-scale bubble column as described in the Materials and Methods section. The acid gas concentration selected for the test falls in the range of those found in some natural gas reservoirs, but more importantly, it enables the experiment’s completion in a reasonable amount of time since we have consistently achieved H 2 S breakthrough around the 2-h mark for HET-TRZ under similar test conditions. The addition of CO 2 to the gaseous test mixture was because it is one of the most common impurities in natural gas and it also has a minimal effect on the H 2 S scavenging performance of triazine-based scavengers .…”

Hydrogen sulfide capture and removal technologies: A comprehensive review of recent developments and emerging trends

“…Nonetheless, owing to their high chemical stability, polymeric membranes are proven to work in harsh environments and can be a very effective pretreatment to increase the efficiency of other technologies when purification of streams with high H 2 S content is desired [405][406][407]. In fact, most of the applications for membranes are focused on natural gas purification where hydrogen sulfide concentration is in the order of 10-20% or even higher [408]. In this regard, the two most important factors that drive this separation are selectivities of H 2 S/CH 4 and H 2 S/CO 2 , which is also the case for biogas desulfurization [407].…”

Polymeric Membranes for H2S and CO2 Removal from Natural Gas for Hydrogen Production: A Review

“…Moreover, with the increasing interest in phasing out coal, the global demand for natural gas is on the rise [4,17]. Technological advances and the growing demand for natural gas have made it possible to revisit sour gas reservoirs previously considered unviable [18][19][20][21][22]. The best known example of this is the Shah gas field in UAE, which has a H 2 S content of 23% and CO 2 content of 10% [15,16].…”