SU1446313A1 - Method of extracting materials from thick underground formations - Google Patents

Abstract

The invention relates to geotechnology and m. used in downhole hydraulic mining and gross testing of powerful productive horizons. The goal is to ensure the stability of the borehole walls and the formation of distribution plugs without removing the well gauge (ha). The method is carried out as follows. Underground formation I am squashed and the GM is placed in it. A well column is installed in the well (K) and its lower end is placed in the range of the rear layer of the lower layer. The development of the formation is carried out in the ascending order with the formation of pillars between the layers. Each layer is treated in the following sequence. The rocks are first eroded in the bed in ascending order by means of a water-air jet while the GM rotates. In the spent chamber of each layer along the axis of the well is placed K with the location of its upper end in the range of the rear sight Mezza waste chamber and the overlying layer. After working off each lower lying layer, cutting off the W of the casing part K in the range of the rear sight above the overlying layer is carried out and the said part is transferred to the used chamber. The length of the cut-off part K is equal to the sum of the height of the chamber and the power of the rear sight. Then, a plug is formed over the re-flown K. Before formation, the plugs in the movable part K from the surface serves lumpy filler. Thereafter, a plug is formed again over the new part K, and when the overlying layers are worked out, the operations are repeated. 1 з.п, ф-л, 3 Il. with e (L 4 4 O5 & 0 & 0

Description

The invention relates to geotechnology and can be used in the downhole hydraulic mining of minerals, as well as in gross sampling of powerful productive horizons.

The purpose of the invention is to ensure the stability of the walls of the well and the formation of separation plugs without removing the well jet.

FIG. 1-3, diagrams illustrating the process flow are presented.

The method is carried out as follows.

The subterranean formation to the lower boundary of the extraction is opened by the borehole 1. To the upper limit of attraction, well 1 is conducted with an increased diameter, a casing is placed in it, and the annulus is cemented. Then the cement plug is drilled and the well is buried in the extraction interval to its lower boundary. Thereafter, an additional expander column 2 is lowered into the well 1, while the external diameter of this column is received in such a way that a gap remains between the walls of the well 1 and column 2. The column can be installed in the borehole 1 with the support and fixing of its upper end on the upper rim of the cement ring 3, which remains after drilling out the cement plug. To do this, the upper end of the column 2 should be broadened.

The height of the extraction interval is divided into layers 4-6 of equal power and on the pillars of 7-9 medes of layers. The height of the pillars is taken based on the specific mining and geological conditions on the basis of experimental experimentation.

The column 2 is placed in the well 1 so that its lower end is located in the interval of the rear sight 7 over the lower layer 4. After this,

d t into the well borehole monitor 10 and proceed to the development of the lower layer 4. Each layer is processed in the following sequence. At first, the rocks are eroded in the layer in ascending order with the help of a water-air jet while rotating the borehole monitor 10, and the fine fractions of the rock

about

five

0 5 Q

Q f

five

0

five

are carried along column 2 and further along the well to the surface by the method of direct washing with gas-liquid flows, and coarse fractions are stored in the chamber. Then, the direct flushing is reversed, and in a sequence from the upper boundary of the deposited rocks to the lower one, these rocks are hydraulically lifted according to the borehole jet monitor

When the rocks break open, part of the air begins to gradually accumulate in the gap between the walls of the well 1 and column 2 and the liquid is pushed out of this gap, therefore during direct washing the velocity flows of liquid with small fractions enter the column 2 and not into the specified gap, and move up this column. Due to this, the walls 1 are not washed out, not, their expansion occurs and the well walls do not collapse. I

After dying up rocks in layer 4 and

The steps of the mazawizirovannogo rock mass to the surface with the formation of the extraction chamber 11 raise the well jet monitor 10 with the location. its nozzles in the interval of the pillar 8 above the layer 5, which is to be refined. When the jetting machine is rotated, the pressure of the air-jet is increased, and the end section of column 2 is cut. To facilitate the cutting process, polyethylene casing pipes can be used as column 2, or an abrasive material, such as sand, can be used to lead into the water mixture.

After cutting, a part of column 2 is lowered under its own weight along the wellbore into chamber 11 and rests with its lower end into the bottom edge, while the upper end of the specified part of the column is located in the range of the rear sight 7 over the lower layer 4. After that, cork 12 over part of the column. This plug can be formed in various ways, but it is most advisable to do this as follows. Lumpy filler, for example, small pebbles, gravel, etc. is fed into the well in the space between the column and the stand of the jetting machine 10. This filler fills the cavity of part of column 2, but due to its size it cannot penetrate between the part of the column and the walls of the in-. tearing up the wells within the pillar 7, Due to this, a plug V2 of coarse aggregate gradually forms over the upper end of the column. After this plug has been formed, a finer material, such as coarse sand, is fed to it, and the space between the large pieces of plug 12 is silted up,

After the formation of cork 12, a similar development of layer 5 is started with the formation of chamber 13. Following the extraction of the massed rock mass from chamber 13 of the vessel 10

15

Claims (2)

 1. A method for extracting materials from thick subterranean formations, including opening the formation with a well, placing a well romonitor therein, testing the formation with layers in an upward order to form pillars of meld layers, placing the columns in the used chamber of each layer along the well axis its upper end in the range of the rear sight between the spent chamber and the uppermost layer; and with the formation of a separating projecter over said upper end, characterized in that, in order to ensure the stability of the borehole walls and the formation of 25 There is a cutting of the column 2 in pre-H2O separating plugs without removing the pillars of the pillar 9. The new part of the pillar is lowered under its own weight and abuts its lower end into the previously formed plug 12, while the upper end of this part of the column is located in the pillar 8 interval Thereafter, a plug is formed again over the new part of the column, and when the overlying layers are worked out, the operations are repeated. In order for the lower end of the column part to abut against the previously formed plug within the rear sight under the waste layer, and the upper end to be located within the rear sight interval. thirty 35 downhole jetting machine, do not install a casing string in the well with its lower end placed in the rear pane interval, after mining each underlying layer, cutting out a part of the casing column in the rear pane interval above the overlying layer and moving the specified part into the exhaust chamber ku over the overflowed column, while the length of the cut-off part of the column is equal to the sum of the height of the chamber and the power of the sight. 2. A method according to claim 1, characterized in that a lumpy filler is supplied to the displaced part of the column from the surface before forming the plug. layer, the length of the column should be equal to the sum of the height of the chamber (layer) and the power of the rear sight. Formula  1. A method for extracting materials from powerful subterranean formations, including opening the formation with a well, placing a borehole romonitor therein, testing the formation in layers in ascending order with forming pads of meld layers, placing in the exhaust chamber of each layer along the axis of the well the column its upper end in the range of the rear sight between the spent chamber and the upper layer; and with the formation of a separation plug over said upper end, characterized in that, in order to ensure the stability of the borehole walls and the formation of separating plugs without removing downhole jetting machine, a casing string is installed in the well with its lower end positioned in the rear pane interval, after each underlying layer is completed, the hydromonitor cuts a part of the casing column in the rear pane interval above the overlying layer and moves the specified part into the waste chamber, then forms a plug over the overburden layer column, with the length of the cut-off part of the column is equal to the sum of the height of the chamber and the power of the rear sight. 2. A method according to claim 1, characterized in that a lumpy filler is supplied to the displaced part of the column from the surface before the cork is formed. Fi8. / Fi8.3