High density environmentally friendly polymer water-based drilling fluid with resistance to 240° c. and saturated salts, preparation method therefor and use thereof

Abstract

The present disclosure relates to the technical field of drilling fluid, and discloses a high density environmentally friendly polymer water-based drilling fluid with resistance to 240° C. and saturated salts, a preparation method therefor and use thereof. The water-based drilling fluid comprises a micro-crosslinked heterocyclic polymer filtrate reducer, a hyper-branched strongly adsorbed filtrate reducer, a nanometer intercalated complex shearing potentiator, a flexible outer and rigid inner microsphere plugging agent, and water, wherein the micro-crosslinked heterocyclic polymer filtrate reducer is prepared by reacting sodium p-styrene sulfonate, N,N,N-trimethyl-3-(2-methylallylamino)-1-propyl ammonium chloride, N,N-diethyl acrylamide, N-vinyl caprolactam, tetramethyl ethylenediamine with phenyl triethoxy silane. The high density environmentally friendly polymer water-based drilling fluid with resistance to 240° C. and saturated salts of the present disclosure can exhibit good performance at high temperature and high salinity conditions, and has desirable weighting capability, it can meet the requirements of drilling well in the deep oil and gas formations.