Comparative study of standard methods of China, ISO and Russia for determining water dew point of natural gas

Water dew point is an important indicator of natural gas quality control and pipelines safe operation, and also a key concern indicator in negotiation of technical agreement for importing Russian natural gas. The paper makes a detailed comparative study on the standard methods of China, ISO and Russia for determining water dew point of natural gas. Firstly, it is the comparison of standard content. Secondly, comparative test was carried out in different laboratories by using the gas source generated by the standard water dew point generator. Finally, according to the standards of China and Russia, the dew point instruments commonly used in the two countries are respectively used to carry out comparative tests at gas transmission stations under different blowing conditions. Through comparative study, it is clear that the biggest difference between the three standards is the blowing mode; in the condition of no interference, the test results of the common water dew point instrument in China and Russia are accurate, reliable and in good agreement with each other; in the presence of interference (possibly alcohols or hydrocarbons), the test results are quite different, the maximum difference is 6.1 ℃. This study provides a support for the technology negotiations of importing Russian natural gas.