SU1693265A1 - Method of hydraulic mining of coal bed - Google Patents

Abstract

The invention relates to mining and m. used for degassing and moistening coal seams. The goal is to improve the uniformity and quality of moisture saturation of the formation near the injection well and reduce the time required to prepare the site for safe and efficient coal mining. From the day surface to the reservoir (P), the coal of the well (C) is drilled. They are cased with pipes and cement the annulus. Perforate C in the plane P and pump the liquid into the P. After holding it in the P, pump the liquid and drain the P. After the degassing of the P is completed, additional fluid is pumped into it in the pressure filtration mode. The working fluid is pumped in portions in a volume of 0.06-0.08 fractions of the total volume. The time interval between the injections of portions of the liquid is 16-17 hours. The method makes it possible to reduce the hydroprocessing of P by 45 days compared with the known methods. 1 il.

Description

The invention relates to the mining industry and can be used in the hydrotreatment of pre-degassed coal seam through surface wells to ensure safe mining operations:

The aim of the invention is to improve the uniformity and quality of the moisture saturation of the formation near the injection well and reduce the time required to prepare the site for safe and efficient coal mining.

The drawing shows a diagram explaining the method.

The method is performed as follows.

From the day surface to the reservoir, the well is drilled, it is cased with pipes, plugged into the annulus, the casing and cement stone are perforated in the plane of the coal seam,

the fluid is injected into the well; it is kept for 24 hours; the fluid and gas are pumped out.

After completion of work on the degassing of an array of coal in the latter in the mode of only pressure filtration, an additional volume of fluid is calculated in batch, calculated using the formula

Odop 0.01 (1 - KostZhp V Nef + 0-zhg, M3, (1)

where Odrp - additional volume of fluid, m;

The cost is transferred to the bound state and the fluid remaining in the formation after it has been pumped out;

Кп - coefficient taking into account fluid withdrawal into host rocks and into the restricted area of the reservoir;

V - volume of processing stocks of ogOs

ABOUT

with

N5 About SL

l, m

h

NEF-effective porosity of coal,%; Burn - the volume of gas carried by the liquid

Ogzh 5,5MO 10Og2, m3,

(2)

-ten

empirical coefficient of 5.51 -10 cent, m;

Qr is the volume of the extracted gas, m3, and each portion of the liquid in the volume (0.06-0.08) 0dop is injected into the well every day with an interval between pressures of 16-17h.

PRI me R, C of the day surface, a well is drilled on the coal seam, it is lined with pipes, tamping of the annulus, perforation of the casing and cement stone in the plane of the coal seam is carried out. Thereafter, fluid injection is carried out in a dismemberment mode, in which an increase in the permeability of the formation occurs, mainly due to the formation of cracks near the injection well of a single hydraulic system and partial dissolution, scouring and removal of carbonates. The liquid is kept in the coal seam within 24 hours, and then it is pumped out from the well zone, thereby freeing methane migration routes. The well is evacuated; gas flow rates are measured. According to the formula (2), an additional volume of liquid is determined taking into account the removal of gas by the latter. Daily in the mode of pressure filtration inject (0.06-0.08) 0d0p fluid. The interval between the injections is 16-17 hours.

So, on the field of the Sokursk mine through surface wells 1 and 2, 2200 and 1790 m3 of fluid were injected into the reservoir Ki2, respectively. The pressure at the wellhead did not exceed 0.6 MPa, the injection rate varied in the range of 6–15 l / s.

Indicators of the hydrotreatment of the coal seam were recorded by flow meters and pressure gauges installed on the injection pipeline of the well.

Daily, two pumps of the CNS-38-132 type pumped into the reservoir Ki2 from the reservoir, firstly pumped fluid through well 1 and then through well 2, while the volume of injected fluid in well 2 turned out to be less due to weather conditions (frost).

Practically hydroprocessing the experimental area through wells 1 and 2

was made for 16 and 13 working shifts, which reduced the time of its preparation for safe coal mining by 45 days. The drawing shows the distribution of moisture in the Ki2 formation after injecting an additional volume of fluid, calculated according to formulas (1) and (2), through wells 1 and 2 to the field of the Sokursk mine, PA Karagandaugol.

FORUMAWLAH AND ISLANDS

The method of hydrotreatment of coal seam, including drilling a well from the surface to the treated reservoir, casing it with pipes, plugging

spaces, well perforation in the coal seam plane, fluid injection into the reservoir, pumping out previously pumped fluid, reservoir degassing and batch injection of fluid in hydraulic dissection and filtration modes, in order to improve the uniformity and quality of water saturation near the injection well, reduce the time site preparation for safe

and efficient coal mining, an additional volume of fluid is injected into the coal seam in the pressure filtration mode after completion of degassing of the coal mass in the amount of

0 0.01 (1-Kost) -Y / -NEf + Ozhg,

where Kost is the amount of fluid that has passed into the associated state in the reservoir, relative units;

K is an empirical coefficient taking into account fluid withdrawal in enclosing rocks and in the marginal zone of the formation, relative units; V is the volume of the processed coal reserves, m3;

Neff - effective porosity of coal,%; Burn - the volume of gas delivered by the liquid, m,

Ogzh 5.51-10 10 -Or2, where Or is the volume of alkaline gas, m3;

5.51 10 10 - empirical coefficient,,

moreover, the liquid injection is carried out in portions in the volume of (0.06-0.08) 0 with an interval between the injections of 16-17 hours.

/ hABA51-H, 2-1-CUzp

Claims (1)

Claim A method of hydrotreating a coal seam, including drilling a well from the surface onto the treated seam, casing it with pipes, grouting the annulus, perforating the well in the plane of the coal seam, injecting fluid into the reservoir, pumping out previously pumped fluid, degassing the reservoir and portioning pumping fluid in hydrofission and filtration modes characterized in that; in order to increase the uniformity and quality of the water saturation of the formation near the injection well, reduce the time required to prepare the site for safe and efficient coal mining, an additional volume of liquid is pumped into the coal seam in pressure filtration mode * after the completion of the work on the degassing of the coal mass in the amount 0 = 0.01 (1 -KostGKU-Nef + Ozhg, where Kost is the fraction of the fluid that has passed into the bound state in the reservoir, rel. K is an empirical coefficient that takes into account the flow of fluid into the host rocks and into the transboundary zone of the reservoir, rel. V - the volume of processed coal reserves, m ³ ; N _E f ~ effective porosity of coal,%; Burn ~ the volume of liquid removed by the gas, m, Ozhg = 5.51 · 10 ¹⁰ · Ογ ^2. where Qr is the volume of alkaline gas, m ³ ; 5.51 U ^'10 - empirical coefficient m' ^3, wherein the fluid pumping amount to produce portions (0.06-0.08) 0 with an interval between injection 16-17 hours. Ventilation drift 51-Κΐ2-ί-Η1 / 3