According to the documents provided by ISO/TC193, it also introduces scope of natural gas property determination, structure of standard document, installation of instruments, sampling criterion, and standardization program for instruments used for determination.

Hydrate formation conditions of (CH_4+CO_2+H_2S) ternary sour natural gases;

This worldwide well-known standard was widely accepted as the guidelines in steel materials selection for sour natural gas environment.

With a large number of developing sour natural gas fields at home and abroad in recent years,many researchers take extra attention to prevenl hydrate plugging problems.

In this paper, it is discussed for the sour gas sweetening technology of Changqing gas field that the methods of the patent formulated MDEA or activated MDEA are used to remove not only H 2S deeply, but also large amounts of CO 2, according to the sour gas characteristic of the Changqing gas field that the CO 2 content is high,the H 2S content is low and CO 2/H 2S ratio is larger.

This paper makes the proposals for sour gas sweetening technology of Changqing gas field that want to remove not only H_2S deeply but also CO_2 in bulk for meeting the commercial gas specification.