DRILLING REJECT BURIAL METHOD Russian patent published in 2003 - IPC

FIELD: oil and gas production. SUBSTANCE: invention relates to environmental protection at the construction of oil and gas wells on land, in particular to methods of burying drilling reject including selection of geometric dimensions of earth storage, removal of fertile land layer and stocking it in temporary dumps during construction of well, digging of earth pit, peripheral erection of banking, waterproofing of bottom and walls of pit, stocking of drilling reject in constructed earth storage, separation of stocked drilling reject into thickened and clarified phases, removal of clarified liquid phase from the pit, introduction of consolidator into thickened phase and agitation, detoxification of thickened phase by solidification, covering with mineral ground, return from temporary dumps and uniform distribution of fertile land layer on mineral ground, installation of lithologic cut of drilling site according to data obtained from engineering-geological estimation (in preproject stage of well construction), analytical calculation of earth storage volume (in project stage of well construction), which envisages increasing earth storage volume relative to planned volume of stocked drilling reject by 15-20% for production drilling reject and 25-35% for exploration drilling reject. When selecting geometric dimensions, minimum allowed distance between bottom of earth storage and highest ground water level as well as minimum allowed depth of upper layer of solidified reject to be buried are taken into account. Before detoxification, consolidating material is selected under laboratory conditions and its ratio to the weight of reject to be solidified is selected such as to provide compression strength of solidified reject up to 0.1 MPa 28 days after consolidating material was added. Covering of solidified reject with mineral ground is accomplished on the depth of the upper layer of reject by at least 1.0 m superior to the thickness of fertile land layer in the region of the well to be constructed. EFFECT: increased environmental safety of buried reject. 3 dwg, 1 tbl