Configuration and application management of online analyzer in natural gas purification plant based on GB 17820-2018

With implementation of GB 17820-2018 Natural Gas, the purification plants under the Natural Gas Purification Plant General of Southwest Oil and Gasfield Company are faced with the requirement of class I gas index value for product natural gas. To achieve the requirement of new standard GB 17820-2018, the existing configuration of on-line monitoring equipment are analyzed by compared with the new standard. According to the correlation degree between the five quality index values(the calorific value, total sulfur content, hydrogen sulfide content, carbon dioxide content and water dew point) and the gas purification plant, the configuration suggestions and application management improvement measures of on-line analyzer are put forward in order to achieve the purpose of reasonable configuration and use of on-line analyzer for product quality index monitoring. The research results show that: (1) among the five quality indexes of natural gas high calorific value, total sulfur content, hydrogen sulfide content, carbon dioxide content and water dew point, in which high calorific value and carbon dioxide content are easy to meet the index value, but water dew point, total sulfur content and hydrogen sulfide content are the key and difficult points in the operation and control of natural gas purification plant, which is easy to exceed the index value in the production process; (2) the water on-line analyzer currently configured in each natural gas purification plant can meet the requirements of water dew point monitoring in GB 17820-2018 and continue to be used; (3) the hydrogen sulfide on-line analyzer currently configured can not meet the requirements of hydrogen sulfide content monitoring in GB 17820-2018 and needs to be reselected and replaced; (4) the quantity of total sulfur on-line analyzer needs to be added; (5) the configuration of carbon dioxide on-line analyzer remains the status quo; (6) the calorific value on-line analyzer is not available for the time being consider.