Gas Hydrate Forecast And Prevention And Control Technology Researching In The Jilin Oilfield

Gas hydrate formation during exploitation and transportation is a recognized operational hazard. It can impose serious accidents such as Valve plug,Gas cut-off,pipeline shutdown and so on. How to effectively avoid gas hydrate in oil and gas production remains a significant assurance issue. This paper commencing with analyses of the basic property of the hydrate,gas hydrate formation mechanism and influencing factors,general gas hydrate forecast model is set up and established.Meanwhile integrating the actual situation in Jilin oilfield, this article do the application of basic researches of alcohol injection and down hole throttle technology respectively, technological achievements has formed as follows:(1)Based on deeply analysesing the thermodynamics behaviors of hydrate formation, using different Model to predict the gas-hydrate generation condition for pure water system and inhibiters system.(2)According to the theory of Hydrate plugging by thermodynamic inhibitors (electrolyte and alcohol), Based on the Status of Jilin Oilfield. This paper has established a reasonable calculation of the amount of methanol injection method,making the determination of alcohol quantity more scientific and reasonable.(3)According to designed well flow rates and SWHP, on the ground of temperature-pressure model based on wellbore radial thermal conduction, coupling hyrate formation condition and gas temperature after choking, this article build the new design method of down hole throttle .In engineering applications, based on the analysis of production characteristics of Jilin oilfield, This paper make alcohol injection and down hole throttle technology parameters designs and site applications of two gas wells. Doing the alcohol injection technological designs for Ji 1# wells and successful implementation. Comparing the inhibitory effect and economic benefit of methanol or glycol, methanol be taken as execution medicament, and detailed construction scheme be maken. Through the down hole throttle technological designs of Ji 1# wells to deeply study the it's adaptiveness and technological process. The two gas wells keep up persistent producing pressure and gas flow rate after practicing this two hydrate prevention measures, which demonstrate that alcohol injection or down hole choke technology can effectively prevent hydrate blockage, guarantee regular production of gas well and improve economic benefit.