Research On Corrosion Inhibitor Protection Of Gathering And Transportation System In Longwangmiao Gas Field

The Longwangmiao Formation gas reservoir,located in the Moxi block of Anyue gas field,is a major exploration discovery of domestic oil and gas in recent years.It has explored the geological reserves of natural gas were 440.383 billion cubic meters.It is one of the super large-scale gas fields discovered in China so far.Efficient and safe development of this reservoir is an important guarantee that can reduce the dependence of natural gas on foreign countries,improve the development of domestic natural gas industry and ensure the national energy security.The Longwangmiao Formation gas reservoir has high temperature and high pressure,containing hydrogen sulfide acarbon nd dioxide.The pH value of the medium in the ground gathering pipeline is low,the sulfur content of Cl-is high,and the flow rate of the pipeline medium is high.The complex environment brings great challenges to the operation of the ground gathering system.Aiming at the on-site process conditions of the Longwangmiao gas reservoir collection and transportation system,a complete set of corrosion inhibitor evaluation and matching application system was established,and more than 200 laboratory simulation experiments were carried out to screen out the most suitable corrosion inhibitor.More than 500 data were obtained through more than 20 sets of laboratory evaluation experiments.According to the evaluation data,a corrosion inhibitor filling process adapted to on-site production and anti-corrosion requirements was designed.After the corrosion inhibitor is applied on site,with the continuous change of the working conditions of the site,the combination of laboratory evaluation and on-site monitoring/detection is used to continuously optimize and improve the corrosion inhibitor application process plan of the Longwangniao Formation gas reservoir.That proved its effectiveness.The results show that the oil-soluble corrosion inhibitor CT2-19 and the water-soluble corrosion inhibitor CT2-19C have the best corrosion inhibition performance for the site conditions of the Longwangmiao Formation gas reservoir,and will not cause problems due to their compatibility.Affect the normal production of gas fields.The designed corrosion inhibitor anti-corrosion solution can effectively suppress the overall corrosion at the site at a slight level.The corrosion inhibitor anti-corrosion technology applied in the ground gathering system of the Longwangniao gas reservoir in the Moxi block of the Anyue gas field has shown a good effectivity.