BUFFER LIQUID Russian patent published in 2022 - IPC C09K8/40 

FIELD: gas and oil industry.

SUBSTANCE: invention relates to the field of cementing casing strings in gas, gas condensate and oil wells, namely to buffer fluids for cleaning extended sections of wellbores in horizontal and directional wells, or in intervals of abnormally low formation pressures. The buffer liquid contains, wt.%: ground powdered quartz grade "B" 11.76-22.86; microspheres of Granulight-2500 brand or Granulight-3500 brand 0.98-12.86; tripolyphosphate 0.495-1.497; stabilizing agent - synthetic polysaccharide brand EasyStab or gelling agent brand ASA-100 0.098-0.495; water 63.73-86.48.

EFFECT: creation of lightweight structured, stabilized buffer fluid with low water loss, providing high carrying capacity, indifferent to drilling and cement slurries.

1 cl, 1 tbl