US 12,241,371 B1 · Integrated mining method of coal breaking, coal extraction and water circulation in U-well and system thereof

Abstract

Disclosed are an integrated mining method and an integrated mining system of coal breaking, coal extraction and water circulation in a U-well. The integrated mining system includes a first ground facility unit, a second ground facility unit, a jet unit and an extraction unit. The first ground facility unit is configured to transport jet fluid to the jet unit. The jet unit is configured to break a coal seam in a sub-segment to obtain broken cinders. The extraction unit is configured to extract a coal-water mixture. The second ground facility unit is configured to receive the coal-water mixture. In response to determining that an extraction of the sub-segment is complete, the jet unit and the extraction unit is configured to move to a next sub-segment using powers provided by the first ground facility unit and the second ground facility unit.

A coal mining method in a U-well, applied in a coal mining system in the U-well, wherein, the coal mining system in the U-well comprises:

a first ground facility unit, a second ground facility unit, a jet unit and an extraction unit;
the coal mining system is disposed in the U-well;
the U-well comprises:
a coal breaking section, an extraction hole and a coal breaking hole;
the coal breaking section is a horizontal drilling section;
wherein, the jet unit is disposed on a side of the coal breaking section close to the extraction hole through the coal breaking hole;
the extraction unit is disposed on a side of the coal breaking section close to the extraction hole through the extraction hole;
the first ground facility unit connects to the jet unit;
the second ground facility unit connects to the extraction unit;
the coal breaking section comprises a plurality of sub-segments;
initial positions of the jet unit and the extraction unit are on a side of the coal breaking section adjacent to the extraction hole;
terminal positions of the jet unit and the extraction unit are on a side of the coal breaking section adjacent to the coal breaking hole;
the method comprises following steps which are performed iteratively until the extraction of the coal breaking section is complete:
transporting, by the first ground facility unit, jet fluid pressurized to the jet unit;
breaking, by the jet unit, a coal seam in one sub-segment of the plurality of sub-segments at a current position according to a preset breaking angle and a preset breaking radius to obtain broken cinders;
wherein, the jet unit comprises:
a jet lance;
wherein, the jet lance is provided with a spray nozzle;
a spray direction of the spray nozzle is at an acute angle to a directional drill pipe of the extraction unit;
extracting, by the extraction unit, a coal-water mixture directionally according to a preset extraction rate;
wherein, the coal-water mixture comprises:
the broken cinders and the jet fluid;
receiving, by the second ground facility unit, the coal-water mixture;
and
in response to determining that an extraction of the sub-segment is complete, moving, by the jet unit and the extraction unit, to a next sub-segment using powers provided by the first ground facility unit and the second ground facility unit;
wherein,
the breaking, by the jet unit, a coal seam in one sub-segment of the plurality of sub-segments at a current position according to a preset breaking angle and a preset breaking radius to obtain broken cinders comprises:
determining the preset extraction rate of the extraction unit;
calculating an injection rate of the jet fluid according to the preset extraction rate of the extraction unit;
and
injecting, by the jet unit, a stream of the jet fluid into the sub-segment according to the injection rate of the jet fluid, the preset breaking angle and the preset breaking radius to break the coal into the broken cinders;
wherein,
the injection rate of the jet fluid is calculated according to following formulas:
Q
⁢
1
=
Q
⁢
2
+
Q
⁢
3
⁢
Q
⁢
2
=
4
⁢
π
⁢
r
⁢
1
k
1
/
m
⁢
(
m
2
⁢
m
+
1
)
⁢
(
ω
2
)
2
⁢
m
+
1
m
⁢
(
(
-
dp
dr
)
⁢
(
1
-
τ
y
-
ω
2
⁢
dp
dr
)
)
1
/
m
×
(
1
-
1
m
+
1
⁢
(
τ
y
-
ω
2
⁢
dp
dr
)
-
m
m
+
1
⁢
(
τ
y
-
ω
2
⁢
dp
dr
)
2
)
wherein, k represents a consistency coefficient;
Q1 represents the injection rate of the jet fluid;
Q2 represents a loss rate of the jet fluid;
Q3 represents the preset extraction rate of the extraction unit;
r represents a radial loss distance;
m represents a flow pattern index;
ω represents a fracture opening;
p represents a pressure of the jet fluid;
and τy represents a shear stress.

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Integrated mining method of coal breaking, coal extraction and water circulation in U-well and system thereof

Life of this patent

Integrated mining method of coal breaking, coal extraction and water circulation in U-well and system thereof

Life of this patent

Abstract

Claims6