As it has many commercial units, more rich operation experiences, more mature technology and has been succeeded in treatment of medium and low H_2S content natural gas, Shell-Paques/Thiopaq process is recommended to import for treatment of plenty such natural gas in southwest oil & gas fields at home.

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.

This article introduced some high sour natural gas purifying processes as follows:Solvent absorption method,membrane separation technology,Hybrisol method and morphysorb method.

Generation mechanism of acid gas in Northeast Sichuan;

Numerical simulation of leakage and dispersion of acid gas in gathering pipeline;

The reasons of overpressure and release conditions of process in one acid gas gathering station were analysed,3 emergency conditions were determined,and the safety release velocity based on rules of safety release was calculated.