METHOD FOR PREVENTING HYDRATE FORMATION IN FIELD SYSTEMS OF GAS COLLECTION Russian patent published in 2017 - IPC E21B43/00 F17D1/05 

FIELD: oil and gas industry.

SUBSTANCE: according to method, inhibitor of hydrate formation is supplied to the loop. To determine the beginning of hydrate formation process, gas temperature is measured at wellhead, actual gas temperature at the loop outlet and ambient temperature are determined. Certain rated values of gas temperature are calculated by the determined model. The actual value of the temperature at the loop output is compared in real with the base value. Additionally, in real-time mode the pressure is measured at wellhead and at the loop output. The theoretical rated value of hydrate formation temperature is taken as the basic temperature value. If actual temperature at the loop output is reduced to values below the base value, the actual pressure value at the loop output is compared with the value obtained in previous measurement cycle, and actual pressure value at the wellhead is compared with the value obtained in previous measurement cycle. If this pressure at the wellhead is increased by certain value and the pressure at the loop output is reduced by certain value, the specific values of which are determined by the cognitive model for given loop, and these dynamics is maintained for a period of time also determined by the cognitive model, then the beginning of hydrate formation process is diagnosed. First, supply of inhibitor to the loop is increased. If pressure values at wellhead and the loop output do not go beyond specified cognitive model, then the theoretical rated value of hydrate formation temperature is corrected according to the cognitive model. The theoretical estimated value of hydrate formation temperature is determined by determined model defined by analytical expression.

EFFECT: optimized hydrate formation inhibitor consumption and improved operation reliability of gas collection field systems.

3 cl, 2 tbl, 3 dwg