The Opportunity of Drilled Solids Use in Lost Circulation Control

Abstract

The design work contains development of the technology of circulation loss control during oil and gas wells drilling. Circulation loss control experience suggests that one of effective loss control methods is loss profiles plugging using inwash of fillers (shredded cellophane, cordage fiber, laminar elastic filler, etc.) In order to exclude the use of artificial fillers, it is proposed to use the drilled rock extracted from this well as a filler at the well drilling sites The special feature of the work is the use of travelling unit, which is installed on general platform and includes all required equipment to provide drilled cuttings injection into a well: slurry preparation block (screen shaker, breaking machine, mixing vessel, slurry storage tank) and slurry injection block (piston pump). Before reinjection drilled solids are treated to the parameters, which can provide proper plugging of circulation loss channels (size and shape, chemical inactivity). The approach can decrease the volume of waste production during well construction process, exclude the use of artificial fillers and provide circulation loss control, which would lead to the decrease of ecological load. The applicability, advantages and disadvantages of the technology have been considered, risks analysis has been implemented and the opportunity of drilled solids use in circulation loss control has been thoroughly esteemed in terms of ecology and legislation as an example of AO Samaraneftegaz, the subsidiary of Rosneft. Low formation pressure, water content, HFT high volumes, sufficient drainage volumes of Rosneft subsidiaries reservoirs – all the above leads to high risks of mud circulation loss during well drilling. Annual circulation loss control time in oil and gas industry is equal to hundreds of thousands hours. Oil and gas wells construction consumes hundreds of thousands tons of casing strings and cement, millions m3 of drilling mud and chemicals.