SU1566046A1 - Method of degassing series of coal strata - Google Patents

Abstract

The invention relates to the mining industry and can be used to reduce the gas content of the developed coal seams. The goal is to increase the efficiency of the degassing method by reducing energy and labor costs. For this, 8 formations of a group of wells 1-7 are drilled to the coal seam formation. In wells 1-7, the working fluid is pumped in the hydrodissection mode before coupling between them. Then, all the working fluid is pumped out through one well 2, the bottom of which is located the lowest in the fall of the lower reservoir of the suite, and the gas is pumped out through the remaining wells 1.3-7. Moreover, pumping is carried out to the fluid level in the well, defined by the formula: A≥H _IJ + L _IJ TGΑ- (H _IJ -H _O ) / A, where I is the number of the well in the row, J is the number of the row, A - well fluid level, m

H _IJ - the depth of the well, the most remote from the pumped well

L _IJ - distance of the I-th well by the fall from the pumped-out well, α - the angle of dip of the formation, hail

H _O - depth of the gas weathering zone, m

A - proportionality factor. 2 Il.

Description

between them on the treated seams. The number of wells and the distance between them is selected based on the condition of the possibility of their hydraulic breakdown. In this case, as a pumping out water of the received well No. 2, the bottomhole of which (B) in the underlying reservoir of the formation is located below the bottom of the remaining wells.

After hydrotreatment of formations, water, used in hydrodissection under the influence of hydrostatic forces, goes to well No. 2 at point (B), jc. Pumping out of this one water well, drain the previously treated zone in the area of the other wells (No. 1, 3-7) and provide drainage of the reservoir and the gas outlet through the wells (W 1, 3-7). 2Q

In order to ensure gas outflow from wells, it is necessary to lower the level in the pumped well by an amount

H.j.H025

but

) j + L; jtgW

thirty

de A - distance from the conventionally zero mark to the wellhead to the level of the pumped liquid, m;

H is the depth in the jth row of the i-th well J of the furthest from the pumped-out well, m;

L is the distance between the jth row

i-th well in the dip of the 35 stratum and pumped-out well, m;

o — dip angle, hail;

K is the depth of the gas weathering zone; 40

a - coefficient of proportionality.

c Q

five

0

five

0

Claims (1)

Invention Formula Method for degassing coal beds, including drilling a group of wells from the surface, perforating casing strings in the plane of coal beds, cyclic injection of working fluid into coal beds in hydrodividing mode through a group of wells until hydraulic breakdown occurs between them, followed by pumping out of the treated coal mass of working fluid and gas extraction, characterized in that, in order to increase the efficiency of the method by reducing energy and labor costs, the working fluid is pumped out through the well Azhinu, the bottom of which is the lowest located in the fall. the lower layer of the retinue, and pumping lead to the level determined from the following mathematical expression: .L, .. tg -H-ii -, where A is the distance from the conventionally zero mark of the wellhead to the level of the pumped liquid, m; H | - depth in the jth row of the i-th well furthest from the pumped-out well, m; i is the number of the well in the row; j - number p yes wells; L .. is the distance between the j-th row and the i-th well by the dip and the pumped-out well, m; o (dip, hail; H0 — depth of the gas weathering zone, m; a - coefficient of proportionality the gas is extracted from the rest of the wells of the group. L one Gae / Gas VJ.6 L1 Aa 4P X, X.  vxz & 4i #  yy Gas W.7 Water 9uz.Z