The relationship between gas interchangeability and adaptability of gas appliance is briefly described,the present situation and existing problems of natural gas interchangeability and adaptability of gas appliance in China are analyzed,and the foreign relevant experience is summarized.

This paper introduces humidification technique used in natural gas conversion process in foreign countries, analyzes test result of humidification practice in Fuyang.

The situation of LPG supply system in Shenzhen City is analyzed,the conversion schemes for pipeline,regulator and gas appliance are discussed,and it is put forward that the natural gas conversion must have the aid of the government policy support.

The technology of transition gas sources for natural gas conversion,including natural gas reforming gas,mixture of natural gas and coal gas with low calorific value and natural gas-air mixture,are introduced.

Taking Wuchang region for example, the natural gas conversion in the aspects of gas network, gas appliances, gas meter, etc.

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.

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.