The invention provides an adsorption pressure
return type blowout control method, which comprises the following steps: intervening when
well control abnormity occurs at the beginning (such as overflow precursor), compounding a
methane adsorbent and a conventional
drilling fluid additive to prepare high-density composite
well control fluid, and injecting the high-density composite
well control fluid into a shaft by a special device at a position 100-200m below a
wellhead according to preset displacement and pressure parameters. According to the method, bubbles in a shaft are adsorbed through an adsorbent, the slippage speed and the
gas phase volume fraction are reduced, and the synergistic effect of static pressure constraint and active adsorption is achieved. Therefore,
back pressure fluctuation can be stabilized in the early stage of gas
cut, gas column expansion and pressure rising are limited, the risk of pressure leakage and secondary eruption is reduced, the purpose of preventing or restraining blowout is achieved, and the gas
cut blowout prevention device is suitable for complex working conditions such as fractured stratums,
deep water, high temperature and
high pressure and narrow-density windows.