CN103323887A - Assessment method and system of coalbed methane reserve volume at coal mining stable region - Google Patents

Abstract

The invention discloses an assessment computing method of coalbed methane reserve volume at a coal mining stable region. The method comprises the following steps of: (1) obtaining effective pressure relief range of a mining stable region; (2) judging application condition of an estimation model; (3) computing surrounding rock pore volume in the mining stable region; (4) obtaining free gas concentration in the mining stable region; (5) estimating residual coal quantity in the mining stable region and residual gas content; (6) estimating the coalbed methane reserve volume in the mining stable region. The study on the effective pressure relief range in the mining stable region is capable of determining the estimation border range of the coalbed methane reserve volume in the mining stable region, the estimation on the estimation model application condition is capable of selecting effective estimation region to guarantee the accuracy of the estimation result, the computing of surrounding rock pore volume and the study on the free gas concentration are capable of accurately estimating the total quantity of the free coalbed methane in the mining stable region, and the study on the residual coal quantity in the mining stable region and residual gas content is capable of accurately estimating the total quantity of adsorption coalbed methane in the mining stable region.

Description

Appraisal procedure and the system of the moving stable region of a kind of Coal Exploitation coal-seam gas reserves

Technical field

The invention belongs to coal field ground coal bed gas extraction technical field, relate to the moving stable region of the surface well extraction Coal Exploitation front coal-seam gas Reserves Assessment of coal-seam gas and calculate.

Background technology

Because be subjected to the restriction of coal winning method, technique and equipment, the rate of extraction can't reach 100% during seam mining, residual a large amount of float coal in the goaf.Simultaneously, also there is certain thickness coal column in gob edge, and the methane desorb of float coal and coal column causes gathers the coal-seam gas that higher concentration is arranged in the goaf.In addition, the pressure released seam gas that produces after the coal seam in the mining effect scope is subjected to mining influence also will enter the goaf by mining-induced fissure.These coal-seam gas remain in underground if leave, on the one hand, can cause serious energy dissipation, can threaten simultaneously the production safety of other contiguous mining face under mine, on the other hand, it may seriously affect terrestrial climate and ecologic environment by the mining-induced fissure earth's surface of overflowing, and therefore needs carry out the coal-seam gas extraction to goaf or the old lane sealed.

The extracting coal bed gas in stable mining region by ground well drilling technology is a kind of new cbm development mode that grows up in the later stage nineties 20th century, mainly be on coal mine gob ground again drilling well, adopt the method for negative pressure extraction, the coal-seam gas that remains in the underground space, rock stratum and the coal seam is extracted also from the coal mine of scrapping (stopping adopting).This technology both can take full advantage of subterranean coal and adopt release antireflection to superincumbent stratum, overcome the shortcoming of the distinctive low ventilative high adsorption of China's coal-bearing strata, can avoid in time again strenuous exercise's phase of superincumbent stratum, thereby realize the maximization of ground well drainage operation life, so both can stop in the goaf gas to be gushed out to contiguous workplace, in time extraction goes out a large amount of clear energy sources again, meets the scientific idea of current " low-carbon environment-friendly doctrine ".

Because the surface drilling construction cost is higher, therefore the comparative analysis of economic interests also is absolutely necessary, this just need to estimate the minimum mash gas extraction total amount of ground drilling in advance, no matter yet circle, colliery at home and abroad, but how to estimate accurately that mash gas extraction reserves in the goaf remain a great problem of rig-site utilization at present.Therefore, adopt stable region coalbed methane ground extraction gordian technique research, can play a role at national coal field gas pumping development field as soon as possible, become a difficult problem that needs to be resolved hurrily.

Summary of the invention

In view of this, technical matters to be solved by this invention provides a kind of method that can accurately estimate the moving stable region of Coal Exploitation coal-seam gas reserves, realize estimation to the moving stable region of Coal Exploitation coal bed gas resource reserves by the method, for feasibility study and the scale of investment design of target area cbm development provides judging basis.

One of purpose of the present invention is the appraisal procedure that proposes the moving stable region of a kind of Coal Exploitation coal-seam gas reserves; Two of purpose of the present invention is the evaluating systems that propose the moving stable region of a kind of Coal Exploitation coal-seam gas reserves.

One of purpose of the present invention is achieved through the following technical solutions:

The appraisal procedure of the moving stable region of a kind of Coal Exploitation provided by the invention coal-seam gas reserves may further comprise the steps:

S1: obtain need estimation coal-seam gas reserves adopt stable region boundary condition, the deployment of digging tunnel and working face extraction technique information;

S2: obtaining needs adopt the stable region working seam basic condition and adjoining rock lithology and tax thereof of estimation coal-seam gas reserves to deposit distribution characteristics;

S3: obtain destruction release height, the degree of depth and the release angle of adopting the stable region adjoining rock that need estimation coal-seam gas reserves;

S4: carry out the model applicable elements and differentiate, calculate and adopt the effective cover thickness in stable region, differentiation is adopted the stable region sealing and whether is satisfied default basic criterion, if satisfy default basic criterion, then enters next step S5;

S5: obtain and adopt ground settlement basin, stable region volume, calculation stability district country rock volume of voids;

S6: obtain and adopt free gas concentration in the stable region;

S7: estimation is adopted and is lost coal amount and residual gas content thereof in the stable region;

S8: bring the key parameter that step S3, S5, S6, S7 obtain into the Reserves Assessment system, finish and adopt stable region coal-seam gas reserve estimate;

S9: judge that whether adopt stable region coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting the coal seam, stable region; If not, then stop gas pumping to adopting the coal seam, stable region.

Further, use following formula estimation to adopt destruction release height, the degree of depth and the release angle of stable region adjoining rock among the described step S3, calculate respectively according to seam inclination is different with coal seam overlying strata lithology.

Further, among the described step S3, the moving boundary angle of adopting that utilizes three times coal minings to learn " three band opinions " is estimated and is adopted stable region roof strata release angle, large 4～10 ° than the boundary angle under the corresponding conditions of roof strata release angles; Stable region floor strata release angle is adopted in the theoretical release angle estimation of protective seam release exploitation in the utilization, and stable region roof and floor relief range is adopted in leak hunting test or testing laboratory's numerical experiments investigation verification of described use down-hole segmentation sealing of hole water filling.

Further, among the described step S4, in adopting the stable region adjoining rock, compose when having strong aquifer, use following formula to finish the model applicable elements and differentiate:

$\mathrm{\Σ}{\mathrm{\Θ}}_i(H_i-h_i\cos {\mathrm{\θ}}_i)\≥5\frac{\mathrm{\ΣM}}{n},$ If satisfy condition, then enter next step;

In the formula, i represents the i layer cap rock between reservoir space up-and-down boundary and the water-bearing zone; Θ represents rock stratum sealing ability adjustment coefficient; H represents the cap rock original thickness; H represents the turn-off of tomography in cap rock; θ represents co-hade; ∑ M represents seam mining thickness; N represents to exploit hierarchy number.

Further, among the described step S5, use following formula to calculate and adopt ground settlement basin, stable region volume:

${\mathrm{<figure-callout\; id="3"\; label="V"\; filenames="HDA00003486406200031.png"\; state="\{\{state\}\}">V</figure-callout>}}_3=\underset{\mathrm{\&Sigma;}}{\&Integral;\&Integral;}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\&Integral;\&Integral;}\sqrt{1+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;x}\right)}^2+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;y}\right)}^2}\mathrm{dxdy},$

$S_{A(x,y)}=\sqrt{{U_A}^2+{W_A}^2}$

$=\mathrm{m\&eta;}\cos \mathrm{\&alpha;}{\left(\begin{array}{c}\frac{{\mathrm{\&pi;b}}^6{(e^{\frac{\mathrm{\&pi;}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\&pi;x}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2},$

In the formula, S _{A (x, y)}The comprehensive displacement of earth's surface, stable region arbitrfary point A is adopted in expression; M represents that the coal seam adopts thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor,

U _MaxExpression earth's surface maximum horizontal movement value; W _MaxThe maximum vertically sinking in expression earth's surface; r ₁, r ₂, r ₃Expression move towards direction, go up a hill and the go down the hill major effect radius of direction, r ₁=H ₁/ tg β, r ₂=H ₂/ tg β, r ₃=H ₃/ tg β; Tg β represents major effect angle tangent; H ₁, H ₂, H ₃The expression workplace moves towards, goes up a hill and adopt deeply on the border of going down the hill; l ₁, l ₂The exploitation length of expression workplace on the strike and across strike.

Further, use underground goaf to bury the method for beam tube test among the described step S6 or the method for analogy experience value obtains to adopt free gas concentration in the stable region.

Further, residual gas content calculates in such a way among the described step S7:

When not having the field survey data, the remaining coal bed gas content in the adjacent coal seam is calculated with the gas pressure relief amount of mine actual measurement adjacent coal seam air content deduction coal seam discharging, and computing formula is as follows:

q _i＝(1-η _i)q _i0

In the formula, q _I0Represent i adjacent layer primitive coalbed gas content; η _iRepresent i adjacent layer coal-seam gas discharging rate;

When working seam mining height during less than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_i=1-\frac{h_i}{h_p}$ p

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; h _pExpression is subjected to the formation of mining influence adjoining rock to run through the crack, and adjacent layer discharges the formation damage scope of pressure released seam gas to workplace.

When working seam mining height during greater than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; M represents mined bed workplace mining height; L represents the mined bed face length.

The estimation of further, adopting stable region coal-seam gas reserves among the described step S8 utilizes respectively single coal bed or coal seam group computation model to finish according to the condition difference:

1. ought adopt the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

2. ought adopt the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

Two of purpose of the present invention is achieved through the following technical solutions:

The evaluating system of the moving stable region of a kind of Coal Exploitation provided by the invention coal-seam gas reserves comprises stope essential information acquisition module, the effective relief range computing module of face surrounding rock, coal-seam gas reserve estimate model service condition discrimination module, face surrounding rock voidage computing module, Reserves Assessment model key parameter preferred module, adopts stable region Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module is used for obtaining stope size, buried depth, roof and floor lithologic distributed intelligence;

The effective relief range computing module of described face surrounding rock is used for obtaining stope roof and floor release height and width;

Described coal-seam gas reserve estimate model service condition discrimination module is used for whether applicable target stope Reserves Assessment of judgment models, if applicable then automatically enter next step, if inapplicable, then gives a warning;

Described face surrounding rock voidage computing module is used for calculating the space cumulative volume that obtains in the stope release country rock;

Described Reserves Assessment model key parameter preferred module is used for obtaining stope and leaves over coal resources, residual coal bed gas content, face surrounding rock crack coal-seam gas concentration;

The described stable region Coal-bed Gas Reserves of adopting is calculated module, is used for calculating and obtains the coal-seam gas reserves;

Further, the described stable region Coal-bed Gas Reserves calculation module of adopting comprises single coal bed computing module and coal seam group computing module;

Described single coal bed computing module, being used for when adopting the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

Described coal seam group computing module, being used for when adopting the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

The invention has the advantages that: the stable region coal bed gas resource Reserves Assessment method of adopting provided by the invention, what made up respectively single coal bed mining conditions and coal seam group mining condition adopts stable region coal-seam gas reserve estimate model, model has not only been considered the release effect of subterranean coal exploitation to exploiting field roof and floor country rock, adopt the investigation of the effective relief range in stable region and can determine to adopt stable region coal-seam gas reserve estimate bounds, wherein, the appraising model applicable elements is differentiated can select effective estimation area, guarantee estimation result's accuracy, the country rock voidage is calculated and free gas concentration is investigated and can more accurately be estimated and adopt the coal-seam gas total amount of dissociating in the stable region, adopt in the stable region and to lose coal amount and residual gas Content inspect thereof and can more accurately estimate to adopt and adsorb the coal-seam gas total amount in the stable region, also considered working face extraction technique, the tunnel is disposed, the impact that enclosing lithologies and ground settlement distribute on the stope crack, can estimate accurately the coal bed gas resource reserves in the moving stable region of Coal Exploitation, for feasibility study and the scale of investment design of target area cbm development provides decision-making foundation.

Description of drawings

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with accompanying drawing, wherein:

Fig. 1 shows the moving effective relief range schematic diagram of stable region country rock of Coal Exploitation;

Fig. 2 shows down-hole segmentation sealing of hole water filling test schematic diagram;

Fig. 3 shows underground goaf and buries coal-seam gas concentration schematic diagram in the beam tube investigation minery;

Fig. 4 shows the relation curve of working seam adjacent layer coal-seam gas discharging rate and interlamellar spacing;

Fig. 5 shows the moving stable region coal-seam gas estimation method of reserve schematic flow sheet of Coal Exploitation;

Fig. 6 shows the moving stable region of Coal Exploitation coal-seam gas reserve estimate system architecture schematic diagram.

Embodiment

Below with reference to accompanying drawing, the preferred embodiments of the present invention are described in detail; Should be appreciated that preferred embodiment only for the present invention is described, rather than in order to limit protection scope of the present invention.

Embodiment 1

Fig. 1 shows the moving effective relief range schematic diagram of stable region country rock of Coal Exploitation; Among the figure, 1 is coal seam goaf, and 2 is working seam, and 3 are the visual nip (absciss layer seam area) that unloads of goaf roof and floor country rock, 4 for the not visible nip (microfissure development area) that effectively unloads of goaf roof and floor country rock, and 5 unload nip for the transition of roof and floor country rock.1,3,4 is the main assessment objective zone of evaluating system among the figure, and 5 because the unload effects that is subject to is less, not enough so that the coal-seam gas in its peripheral coal rock layer by this zone, has formed the border in assessment objective zone.

Fig. 2 shows down-hole segmentation sealing of hole water filling test schematic diagram; Among the figure, 6 is working seam, and 7 are the observation chamber, and 8 are observation boring, and 9 is water guide (gas) fissure zone, and 10 is the roof caving band.The boring at construction one any elevation angle in the roof in the down-hole, carry out notes (putting) water of differential mode, according to annotate (putting) water yield can judge be subjected to that recovery activity affects effectively unload the pressure zone maximum height, can match obtain effective release border in assessment objective zone (namely adopting the stable region) by a plurality of Test Point Datas.

Fig. 3 shows underground goaf and buries coal-seam gas concentration schematic diagram in the beam tube investigation minery; The advance of the face is laid beam tube near the monitoring point time behind the coalcutter support, lay 3 beam tubes, second beam tube 150m of first beam tube distance, the 3rd beam tube 100m of second beam tube distance.Arrange 4～5 sampling spots on the every beam tube, each sampling spot spacing 40～50m, sampling spot numbering situation is seen diagram.All beam tubes all pass from protective casing (steel pipe); protective casing is imbedded the float coal below, and built-in pipe adopts 2 cun steel pipes of diameter, penetrates therein the beam tube of 4～5 ф 8mm/12mm different colours; every beam tube is responsible for the gas sample of a measuring point, and each sampling head is raised more than the 0.5m.The sampling head of each beam tube, can adopt at the fire dam place and stay the mode of establishing boring, drilling design diameter 60 ㎜ to the crossheading fire dam at the protection downward-extension of sleeve pipe.Confirm whole beam tube and contact place without leakage, after workplace pushed away beam tube 20m, regularly (4～5 days/time) carried out gas sample to each beam tube.Gas sample should be carried out during infrabar, namely between at 2 to 4 o'clock in afternoon.Carry out before the gas sample, should connect gas sample draw-off pump and move 5～10 minutes, discharge air in the beam tube, to guarantee gathering the gas sample from goaf measuring point place.

Fig. 4 shows the relation curve of working seam adjacent layer coal-seam gas discharging rate and interlamellar spacing, is followed successively by from top to bottom adjacent layer; Adjacent layer under the gently inclined seam; The relation curve of adjacent layer under inclination, the steeply pitching seam.

Fig. 5 shows the moving stable region coal-seam gas estimation method of reserve schematic flow sheet of Coal Exploitation, Fig. 6 shows the moving stable region of Coal Exploitation coal-seam gas reserve estimate system architecture schematic diagram, as shown in the figure: the appraisal procedure of the moving stable region of a kind of Coal Exploitation provided by the invention coal-seam gas reserves may further comprise the steps:

S1: obtain need estimation coal-seam gas reserves adopt stable region boundary condition, the deployment of digging tunnel and working face extraction technique information;

S2: obtaining needs adopt the stable region working seam basic condition and adjoining rock lithology and tax thereof of estimation coal-seam gas reserves to deposit distribution characteristics;

S3: obtain destruction release height, the degree of depth and the release angle of adopting the stable region adjoining rock that need estimation coal-seam gas reserves;

S4: carry out the model applicable elements and differentiate, calculate and adopt the effective cover thickness in stable region, differentiation is adopted the stable region sealing and whether is satisfied default basic criterion, if satisfy default basic criterion, then enters next step S5;

S5: obtain and adopt ground settlement basin, stable region volume, calculation stability district country rock volume of voids;

S6: obtain and adopt free gas concentration in the stable region;

S7: estimation is adopted and is lost coal amount and residual gas content thereof in the stable region;

S8: bring the key parameter that step S3, S5, S6, S7 obtain into the Reserves Assessment system, finish and adopt stable region coal-seam gas reserve estimate;

S9: judge that whether adopt stable region coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting the coal seam, stable region; If not, then stop gas pumping to adopting the coal seam, stable region.

Use following formula estimation to adopt destruction release height, the degree of depth and the release angle of stable region adjoining rock among the described step S3, calculate respectively according to seam inclination is different with coal seam overlying strata lithology.

Among the described step S3, the moving boundary angle of adopting that utilizes three times coal minings to learn " three band opinions " is estimated and is adopted stable region roof strata release angle, large 4～10 ° than the boundary angle under the corresponding conditions of roof strata release angles; Stable region floor strata release angle is adopted in the theoretical release angle estimation of protective seam release exploitation in the utilization, and stable region roof and floor relief range is adopted in leak hunting test or testing laboratory's numerical experiments investigation verification of described use down-hole segmentation sealing of hole water filling.

Among the described step S4, in adopting the stable region adjoining rock, compose when having strong aquifer, use following formula to finish the model applicable elements and differentiate:

If satisfy condition, then enter next step; If do not satisfy condition, then need to adopt additive method to carry out the coal-seam gas Reserves Assessment;

In the formula, i represents the i layer cap rock between reservoir space up-and-down boundary and the water-bearing zone; Θ represents rock stratum sealing ability adjustment coefficient; H represents the cap rock original thickness; H represents the turn-off of tomography in cap rock; θ represents co-hade; ∑ M represents seam mining thickness; N represents to exploit hierarchy number.

Among the described step S5, use following formula to calculate and adopt ground settlement basin, stable region volume:

${\mathrm{<figure-callout\; id="3"\; label="V"\; filenames="HDA00003486406200031.png"\; state="\{\{state\}\}">V</figure-callout>}}_3=\underset{\mathrm{\&Sigma;}}{\&Integral;\&Integral;}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\&Integral;\&Integral;}\sqrt{1+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;x}\right)}^2+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;y}\right)}^2}\mathrm{dxdy},$

$S_{A(x,y)}=\sqrt{{U_A}^2+{W_A}^2}$

$=\mathrm{m\&eta;}\cos \mathrm{\&alpha;}{\left(\begin{array}{c}\frac{{\mathrm{\&pi;b}}^6{(e^{\frac{\mathrm{\&pi;}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\&pi;x}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2},$

In the formula, S _{A (x, y)}The comprehensive displacement of earth's surface, stable region arbitrfary point A is adopted in expression; M represents that the coal seam adopts thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor,

U _MaxExpression earth's surface maximum horizontal movement value; W _MaxThe maximum vertically sinking in expression earth's surface; r ₁, r ₂, r ₃Expression move towards direction, go up a hill and the go down the hill major effect radius of direction, r ₁=H ₁/ tg β, r ₂=H ₂/ tg β, r ₃=H ₃/ tg β; Tg β represents major effect angle tangent; H ₁, H ₂, H ₃The expression workplace moves towards, goes up a hill and adopt deeply on the border of going down the hill; l ₁, l ₂The exploitation length of expression workplace on the strike and across strike.

Use underground goaf to bury the method for beam tube test among the described step S6 or the method for analogy experience value obtains to adopt free gas concentration in the stable region.

Residual gas content calculates in such a way among the described step S7:

When not having the field survey data, the remaining coal bed gas content in the adjacent coal seam is calculated with the gas pressure relief amount of mine actual measurement adjacent coal seam air content deduction coal seam discharging, and computing formula is as follows:

q _i＝(1-η _i)q _i0

In the formula, q _I0Represent i adjacent layer primitive coalbed gas content; η _iRepresent i adjacent layer coal-seam gas discharging rate;

When working seam mining height during less than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_i=1-\frac{h_i}{h_p}$

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; h _pExpression is subjected to the formation of mining influence adjoining rock to run through the crack, and adjacent layer discharges the formation damage scope of pressure released seam gas to workplace.

When working seam mining height during greater than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_i=100-\frac{{0.47h}_i}{M}-\frac{84.04h_i}{L}$

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; M represents mined bed workplace mining height; L represents the mined bed face length.

The estimation of adopting stable region coal-seam gas reserves among the described step S8 utilizes respectively single coal bed or coal seam group computation model to finish according to the condition difference:

1. ought adopt the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

2. ought adopt the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

The present embodiment also provides the evaluating system of the moving stable region of a kind of Coal Exploitation coal-seam gas reserves, comprises stope essential information acquisition module, the effective relief range computing module of face surrounding rock, coal-seam gas reserve estimate model service condition discrimination module, face surrounding rock voidage computing module, Reserves Assessment model key parameter preferred module, adopts stable region Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module is used for obtaining stope size, buried depth, roof and floor lithologic distributed intelligence;

The effective relief range computing module of described face surrounding rock is used for obtaining stope roof and floor release height and width;

Described coal-seam gas reserve estimate model service condition discrimination module is used for whether applicable target stope Reserves Assessment of judgment models, if applicable then automatically enter next step, if inapplicable, then gives a warning;

Described face surrounding rock voidage computing module is used for calculating the space cumulative volume that obtains in the stope release country rock;

Described Reserves Assessment model key parameter preferred module is used for obtaining stope and leaves over coal resources, residual coal bed gas content, face surrounding rock crack coal-seam gas concentration;

The described stable region Coal-bed Gas Reserves of adopting is calculated module, is used for calculating and obtains the coal-seam gas reserves;

The described stable region Coal-bed Gas Reserves calculation module of adopting comprises single coal bed computing module and coal seam group computing module;

Described single coal bed computing module, being used for when adopting the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

Described coal seam group computing module, being used for when adopting the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

Embodiment 2

The difference of the present embodiment and embodiment 1 only is:

The present embodiment 2 provides the appraisal procedure of the moving stable region of a kind of Coal Exploitation coal-seam gas reserves, may further comprise the steps:

1) obtains the information such as stable region boundary condition, the deployment of digging tunnel and working face extraction technique of adopting that need estimation coal-seam gas reserves;

2) obtain adopt the stable region working seam basic condition and adjoining rock lithology and tax thereof that need to estimate the coal-seam gas reserves and deposit distribution characteristics;

3) obtain destruction release height, the degree of depth and the release angle of adopting the stable region adjoining rock that needs estimation coal-seam gas reserves;

4) carry out the model applicable elements and differentiate, if satisfy basic criterion then enter next step; If do not satisfy this criterion of model-based, then need to seek additive method and finish estimation;

5) obtain and adopt ground settlement basin, stable region volume, calculation stability district country rock volume of voids;

6) obtain and adopt free gas concentration in the stable region;

7) estimation is adopted and is lost coal amount and residual gas content thereof in the stable region;

8) with each key parameter substitution system, finish Coal Seams on Infection Zones of Coal Mining gas reserve estimate.

In the described step 1), the range of application of assessment technology is to be subject to the seam mining impact, and the colliery that impact has stopped is regional.

In the described step 3), use experience formula estimation adjoining rock destruction height and the degree of depth, used formula is different as follows respectively according to condition:

1. seam inclination is (moderate dip, medium dip) coal seam of 0 °～54 °

In the overlying strata of coal seam be hard, in when hard, weak, dead-soft incompetent beds or its alternating layers, the water guide slit band maximum height of thick seam slicing system can be selected the formula calculating in the table 1.

The height of the water conductive fracture zone computing formula of table 1 thick seam slicing system

Annotate: Σ M-accumulative total is adopted thick; The formula scope of application: individual layer is adopted thick 1～3m, and accumulative total is adopted the thick 15m of being no more than; In the computing formula ± number Xiang Weizhong error.

2. seam inclination is (high-dipping) coal seam of 55 °～90 °

Coal seam top, base plate be hard, in hard, soft stratum, the formula calculating in the height of the water conductive fracture zone free list 2 when exploit with caving method.

Table 2 steeply pitching seam height of the water conductive fracture zone computing formula

Annotate: h-working seam hangs down high; M-working seam normal thickness.

Height of the water conductive fracture zone calculates when 3. exploiting coal seam group with near interval

When the vertical caving zone height H that produces during greater than back production lower floor coal apart from h of a \ upper and lower two-layer coal is emitted, lower floor's caving zone is very little to the upper strata mining effect, can calculate respectively by the thickness in upper and lower coal seam separately height of the water conductive fracture zone and caving zone height, get that wherein the large person of absolute altitude value is as the height of the water conductive fracture zone of two-layer coal, the caving zone height is then got the caving zone height of day-coal.

The caving zone of b \ lower floor coal touches or when entering day-coal fully, the water guide slit band maximum height of day-coal is by the THICKNESS CALCULATION of this layer coal, the water guide slit band maximum height of lower floor's coal then adopts the comprehensive mining high computational of upper and lower layer coal, if the comprehensive mining height is less than lower floor's coal mining height, then do not use comprehensive height, get wherein the large person of absolute altitude value as the water guide slit band maximum height of two-layer coal.

The comprehensive mining thickness of upper and lower layer coal can be calculated as follows:

In the formula, h _1-2Normal distance between the-upper and lower layer coal; The caving zone height of y-lower floor's coal with adopt thick ratio.

\ if the spacing of upper and lower layer coal is very little, then comprehensive mining thickness is got the thick sum of two-layer coal to c.Obtain after the comprehensive mining thickness, the caving zone height in the time of can exploiting according to single coal bed and the computing formula of height of the water conductive fracture zone calculate height of the water conductive fracture zone under the multiple seam mining conditions.

4. base plate release depth calculation

In the formula: x _aThe length of-Yielding Zone of Coal Pillar; -floor rock angle of internal friction.

Yielding Zone of Coal Pillar length is calculated as follows:

In the formula: The angle of internal friction in-coal seam; C _mThe cohesion in-coal seam; M-mining thickness; H-coal seam depth of burial; The unit weight of γ-floor rock;

In the described step 3), utilize the moving boundary angle of adopting of three times coal mining " three band opinions " to estimate target area roof strata release angle, large 4～10 ° than the boundary angle under the corresponding conditions of roof strata release angles; The theoretical release angle estimation target area floor strata release angle of protective seam release exploitation in the utilization.

In the described step 3), use the water filling of down-hole segmentation sealing of hole to leak hunting and test or testing laboratory's numerical experiments investigation verification object district roof and floor relief range.

In the described step 4), in adopting the stable region adjoining rock, compose when having strong aquifer, use following formula to finish the model applicable elements and differentiate.

$\mathrm{\&Sigma;}{\mathrm{\&Theta;}}_i(H_i-h_i\cos {\mathrm{\&theta;}}_i)\&GreaterEqual;5\frac{\mathrm{\&Sigma;M}}{n}$

In the formula, the i layer cap rock between i-reservoir space up-and-down boundary and the water-bearing zone; Θ-rock stratum sealing ability is adjusted coefficient; H-cap rock original thickness, m; The turn-off of h-tomography in cap rock, m; θ-co-hade, °; ∑ M-seam mining thickness, m; N-exploitation hierarchy number.

Use following table 3 to determine the common lithology of coal field rock stratum sealing ability coefficient Θ.

The common lithology of table 3 coal field rock stratum sealing ability coefficient table

In the described step 5), use following formula to calculate and adopt ground settlement basin, stable region volume.

${\mathrm{<figure-callout\; id="3"\; label="V"\; filenames="HDA00003486406200031.png"\; state="\{\{state\}\}">V</figure-callout>}}_3=\underset{\mathrm{\&Sigma;}}{\&Integral;\&Integral;}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\&Integral;\&Integral;}\sqrt{1+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;x}\right)}^2+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;y}\right)}^2}\mathrm{dxdy}$

In the formula, the comprehensive displacement of SA-earth's surface, target area arbitrfary point A, m.

Use following formula to calculate the comprehensive displacement of earth's surface, target area arbitrfary point A (x, y):

$S_A=\sqrt{{U_A}^2+{W_A}^2}$

$=\mathrm{m\&eta;}\cos \mathrm{\&alpha;}{\left(\begin{array}{c}\frac{{\mathrm{\&pi;b}}^6{(e^{\frac{\mathrm{\&pi;}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\&pi;x}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2}$

In the formula, m-coal seam is adopted thick, m; η-subsidence factor; α-seam inclination, °; B-displacement factor,

U _Max-earth's surface maximum horizontal movement value; W _MaxThe maximum vertically sinking in-earth's surface; The major effect radius of r1, r2, the r3-direction of moving towards direction, go up a hill and go down the hill, m, r ₁=H ₁/ tg β, r ₂=H ₂/ tg β, r ₃=H ₃/ tg β; Tg β-major effect angle tangent; H ₁, H ₂, H ₃-workplace moves towards, goes up a hill and m is adopted deeply on the border of going down the hill; The exploitation length of l1, l2-workplace on the strike and across strike, m.

In the described step 6), the use underground goaf buries the method for beam tube test or the method for analogy experience value obtains to adopt free gas concentration in the stable region.

In the described step 7), when not having the field survey data, the remaining coal bed gas content in the adjacent coal seam can be surveyed with mine the gas pressure relief amount calculating of adjacent coal seam air content deduction coal seam discharging, and computing formula is as follows:

q _i＝(1-η _i)q _i0

In the formula, qi0-i adjacent layer primitive coalbed gas content, m3/t; η _iThe-the i adjacent layer coal-seam gas discharging rate, %.

When working seam mining height during less than 4.5m, η _iCan be calculated as follows or choose by Fig. 4.

${\mathrm{\&eta;}}_i=1-\frac{h_i}{h_p}$

In the formula, h _iThe-the i adjacent layer and mined bed vertical range, m; h _p-be subjected to the formation of mining influence adjoining rock to run through the crack, adjacent layer discharges the formation damage scope of pressure released seam gas, m to workplace.

When working seam mining height during greater than 4.5m, η _iBe calculated as follows.

${\mathrm{\&eta;}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

In the formula, h _iThe-the i adjacent layer and mined bed vertical range, m; M-mined bed workplace mining height, m; L-mined bed face length, m.

In the described step 8), different according to condition, utilize respectively single coal bed or coal seam group computation model to finish Reserves Assessment.

1. single coal bed condition

When in adopting relief range, except working seam, not having other coal seams, utilize following formula to finish Reserves Assessment and calculate:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}$

2. coal seam group condition

When in adopting relief range, except working seam, also having other coal seams, utilize following formula to finish Reserves Assessment and calculate:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁-adopt and leave over coal total amount, t in the stable region; q ₁-adopt and lose coal gas remainder quantity, m3/t in the stable region; N-adopt coal-seam gas volume fraction in the stable region, %; V-adopt stable region void volume, m3; Mi0-i adjacent layer coal total amount, t; Qi0-original the gas bearing capacity of i adjacent layer, m3/t; η i-different layers spacing the next layer gas emission index, %.

Embodiment 3

The difference of the present embodiment and embodiment 2 only is:

Referring to the moving stable region coal-seam gas estimation method of reserve of the Coal Exploitation of Fig. 5 the present embodiment 3, comprise the steps:

1) obtains key messages such as needing the moving stable region of Coal Exploitation of estimation coal-seam gas reserves bounds, the deployment of digging tunnel, working face extraction technique and exploiting field hydrogeological condition;

2) obtain adopt the stable region working seam basic condition and adjoining rock lithology and tax thereof that need to estimate the coal-seam gas reserves and deposit distribution characteristics;

3) obtain destruction release height, the degree of depth and the release angle of adopting the stable region adjoining rock that needs estimation coal-seam gas reserves;

At first, use experience formula estimation adjoining rock destruction height and the degree of depth, used formula is different as follows respectively according to condition:

1. seam inclination is (moderate dip, medium dip) coal seam destruction height of 0 °～54 °

In the overlying strata of coal seam be hard, in when hard, weak, dead-soft incompetent beds or its alternating layers, the water guide slit band maximum height of thick seam slicing system can be selected the formula calculating in the table 7.

The height of the water conductive fracture zone computing formula of table 7 thick seam slicing system

Annotate: Σ M-accumulative total is adopted thick; The formula scope of application: individual layer is adopted thick 1～3m, and accumulative total is adopted the thick 15m of being no more than; In the computing formula ± number Xiang Weizhong error.

2. seam inclination is (high-dipping) coal seam destruction height of 55 °～90 °

Coal seam top, base plate be hard, in hard, soft stratum, the formula calculating in the height of the water conductive fracture zone free list 8 when exploit with caving method.

Table 8 steeply pitching seam height of the water conductive fracture zone computing formula

Annotate: h-working seam hangs down high; M-working seam normal thickness.

3. exploit the coal seam group with near interval destruction height

When the vertical caving zone height H that produces during greater than back production lower floor coal apart from h of a \ upper and lower two-layer coal is emitted, lower floor's caving zone is very little to the upper strata mining effect, can calculate respectively by the thickness in upper and lower coal seam separately height of the water conductive fracture zone and caving zone height, get that wherein the large person of absolute altitude value is as the height of the water conductive fracture zone of two-layer coal, the caving zone height is then got the caving zone height of day-coal.

The caving zone of b \ lower floor coal touches or when entering day-coal fully, the water guide slit band maximum height of day-coal is by the THICKNESS CALCULATION of this layer coal, the water guide slit band maximum height of lower floor's coal then adopts the comprehensive mining high computational of upper and lower layer coal, if the comprehensive mining height is less than lower floor's coal mining height, then do not use comprehensive height, get wherein the large person of absolute altitude value as the water guide slit band maximum height of two-layer coal.

The comprehensive mining thickness of upper and lower layer coal can be calculated as follows:

In the formula, h _1-2Normal distance between the-upper and lower layer coal; The caving zone height of y-lower floor's coal with adopt thick ratio.

\ if the spacing of upper and lower layer coal is very little, then comprehensive mining thickness is got the thick sum of two-layer coal to c.Obtain after the comprehensive mining thickness, the caving zone height in the time of can exploiting according to single coal bed and the computing formula of height of the water conductive fracture zone calculate height of the water conductive fracture zone under the multiple seam mining conditions.

4. base plate release collapse dept calculates

In the formula: x _aThe length of-Yielding Zone of Coal Pillar;

-floor rock angle of internal friction.

Yielding Zone of Coal Pillar length is calculated as follows:

In the formula:

The angle of internal friction in-coal seam; C _mThe cohesion in-coal seam; M-mining thickness; H-coal seam depth of burial; The unit weight of γ-floor rock;

5. adopt the stable region release and destroy the border angle

Utilize the moving boundary angle of adopting of three times coal mining " three band opinions " to estimate target area roof strata release angle, large 4～10 ° than the boundary angle under the corresponding conditions of roof strata release angles; The theoretical release angle estimation target area floor strata release angle of protective seam release exploitation in the utilization.

Secondly, referring to Fig. 2, use the water filling of down-hole segmentation sealing of hole to leak hunting and test or testing laboratory's numerical experiments investigation verification object district roof and floor relief range.

4) in conjunction with obtain adopt stable region adjoining rock destruction height and roof and floor lithologic distributes, hydrogeological characteristics, carry out the differentiation of model applicable elements, if satisfy basic criterion then enter next step; If do not satisfy this criterion of model-based, then need to seek additive method and finish estimation;

In adopting the stable region adjoining rock, do not compose when having strong aquifer, ignore this step; In adopting the stable region adjoining rock, compose when having strong aquifer, use following formula to finish the model applicable elements and differentiate.

$\mathrm{\&Sigma;}{\mathrm{\&Theta;}}_i(H_i-h_i\cos {\mathrm{\&theta;}}_i)\&GreaterEqual;5\frac{\mathrm{\&Sigma;M}}{n}$

In the formula, the i layer cap rock between i-reservoir space up-and-down boundary and the water-bearing zone; Θ-rock stratum sealing ability is adjusted coefficient; H-cap rock original thickness, m; The turn-off of h-tomography in cap rock, m; θ-co-hade, °; ∑ M-seam mining thickness, m; N-exploitation hierarchy number.

Use following table 9 to determine the common lithology of coal field rock stratum sealing ability coefficient Θ.

The common lithology of table 9 coal field rock stratum sealing ability coefficient table

5) obtain and adopt ground settlement basin, stable region volume, calculation stability district country rock volume of voids;

Use following formula to calculate and adopt ground settlement basin, stable region volume.

${\mathrm{<figure-callout\; id="3"\; label="V"\; filenames="HDA00003486406200031.png"\; state="\{\{state\}\}">V</figure-callout>}}_3=\underset{\mathrm{\&Sigma;}}{\&Integral;\&Integral;}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\&Integral;\&Integral;}\sqrt{1+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;x}\right)}^2+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;y}\right)}^2}\mathrm{dxdy}$

In the formula, the comprehensive displacement of SA-earth's surface, target area arbitrfary point A, m.

Use following formula to calculate the comprehensive displacement of earth's surface, target area arbitrfary point A (x, y):

$S_A=\sqrt{{U_A}^2+{W_A}^2}$

$=\mathrm{m\&eta;}\cos \mathrm{\&alpha;}{\left(\begin{array}{c}\frac{{\mathrm{\&pi;b}}^6{(e^{\frac{\mathrm{\&pi;}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\&pi;x}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2}$

In the formula, m-coal seam is adopted thick, m; η-subsidence factor; α-seam inclination, °; B-displacement factor,

U _Max-earth's surface maximum horizontal movement value; W _MaxThe maximum vertically sinking in-earth's surface; The major effect radius of r1, r2, the r3-direction of moving towards direction, go up a hill and go down the hill, m, r ₁=H ₁/ tg β, r ₂=H ₂/ tg β, r ₃=H ₃/ tg β; Tg β-major effect angle tangent; H ₁, H ₂, H ₃-workplace moves towards, goes up a hill and m is adopted deeply on the border of going down the hill; The exploitation length of l1, l2-workplace on the strike and across strike, m.

6) referring to accompanying drawing 3, the use underground goaf buries the method for beam tube test or the method for analogy experience value obtains to adopt free gas concentration in the stable region;

7) estimation is adopted and is lost coal amount and residual gas content thereof in the stable region according to Field Production Data;

When not having the field survey data, the remaining coal bed gas content in the adjacent coal seam can be surveyed with mine the gas pressure relief amount calculating of adjacent coal seam air content deduction coal seam discharging, and computing formula is as follows:

q _i＝(1-η _i)q _i0

In the formula, qi0-i adjacent layer primitive coalbed gas content, m3/t; η _iThe-the i adjacent layer coal-seam gas discharging rate, %.

Discharging degree and the interlamellar spacing of the next layer gas are inversely proportional to, and upper adjacent layer discharging scope can feed through to l70m, and lower adjacent layer discharging scope can be to 50m.When working seam mining height during less than 4.5m, η _iCan be calculated as follows or choose by Fig. 4.

${\mathrm{\&eta;}}_i=1-\frac{h_i}{h_p}$

In the formula, h _iThe-the i adjacent layer and mined bed vertical range, m; h _p-be subjected to the formation of mining influence adjoining rock to run through the crack, adjacent layer discharges the formation damage scope of pressure released seam gas, m to workplace.

When working seam mining height during greater than 4.5m, η _iBe calculated as follows.

${\mathrm{\&eta;}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

In the formula, h _iThe-the i adjacent layer and mined bed vertical range, m; M-mined bed workplace mining height, m; L-mined bed face length, m.

8) with each key parameter substitution computing system, finish Coal Seams on Infection Zones of Coal Mining gas reserve estimate.

Referring to Fig. 6, the stable region Coal-bed Gas Reserves of adopting of the present embodiment is calculated system, comprising:

1. stope essential information acquisition module is in order to obtain the essential informations such as stope size, buried depth, roof and floor lithologic distribution;

2. the effective relief range computing module of face surrounding rock, clear and definite stope roof and floor release height and width provide the border foundation for follow-up reserves calculate;

3. coal-seam gas reserve estimate model service condition discrimination module is judged whether applicable target stope Reserves Assessment of this model, if applicable then automatically enter next step, if inapplicable, then gives a warning;

4. face surrounding rock voidage computing module calculates the space cumulative volume that obtains in the stope release country rock;

5. Reserves Assessment model key parameter preferred acquisition module, obtain stope and leave over the key parameters such as coal resources, residual coal bed gas content, face surrounding rock crack coal-seam gas concentration;

6. adopt the stable region Coal-bed Gas Reserves and calculate module, calculate and obtain the coal-seam gas reserves.

Adopt stable region Coal-bed Gas Reserves calculation module and comprise two class computation models, can realize the reserve estimate of single coal bed condition and coal seam group condition:

A the single coal bed condition

When in adopting relief range, except working seam, not having other coal seams, utilize following formula to finish Reserves Assessment and calculate:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}$

B the coal seam group condition

When in adopting relief range, except working seam, also having other coal seams, utilize following formula to finish Reserves Assessment and calculate:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁-adopt and leave over coal total amount, t in the stable region; q ₁-adopt and lose coal gas remainder quantity, m3/t in the stable region; N-adopt coal-seam gas volume fraction in the stable region, %; V-adopt stable region void volume, m3; Mi0-i adjacent layer coal total amount, t; Qi0-original the gas bearing capacity of i adjacent layer, m3/t; η i-different layers spacing the next layer gas emission index, %.

The above is the preferred embodiments of the present invention only, is not limited to the present invention, and obviously, those skilled in the art can carry out various changes and modification and not break away from the spirit and scope of the present invention the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.

Claims (10)

1. the appraisal procedure of the moving stable region of Coal Exploitation coal-seam gas reserves is characterized in that: may further comprise the steps:

S1: obtain need estimation coal-seam gas reserves adopt stable region boundary condition, the deployment of digging tunnel and working face extraction technique information;

S2: obtaining needs adopt the stable region working seam basic condition and adjoining rock lithology and tax thereof of estimation coal-seam gas reserves to deposit distribution characteristics;

S3: obtain destruction release height, the degree of depth and the release angle of adopting the stable region adjoining rock that need estimation coal-seam gas reserves;

S4: carry out the model applicable elements and differentiate, calculate and adopt the effective cover thickness in stable region, differentiation is adopted the stable region sealing and whether is satisfied default basic criterion, if satisfy default basic criterion, then enters next step S5;

S5: obtain and adopt ground settlement basin, stable region volume, calculation stability district country rock volume of voids;

S6: obtain and adopt free gas concentration in the stable region;

S7: estimation is adopted and is lost coal amount and residual gas content thereof in the stable region;

S8: bring the key parameter that step S3, S5, S6, S7 obtain into the Reserves Assessment system, finish and adopt stable region coal-seam gas reserve estimate;

S9: judge that whether adopt stable region coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting the coal seam, stable region; If not, then stop gas pumping to adopting the coal seam, stable region.

2. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, it is characterized in that: use following formula estimation to adopt destruction release height, the degree of depth and the release angle of stable region adjoining rock among the described step S3, calculate respectively according to seam inclination is different with coal seam overlying strata lithology.

3. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, it is characterized in that: among the described step S3, utilizing three times coal minings to learn three estimates and adopts stable region roof strata release angle, large 4～10 ° than the boundary angle under the corresponding conditions of roof strata release angles with the moving boundary angle of adopting of opinion; Stable region floor strata release angle is adopted in the theoretical release angle estimation of protective seam release exploitation in the utilization, uses leak hunting test or testing laboratory's numerical experiments investigation verification of down-hole segmentation sealing of hole water filling to adopt stable region roof and floor relief range.

4. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, it is characterized in that: among the described step S4, compose when having strong aquifer in adopting the stable region adjoining rock, use following formula to finish the model applicable elements and differentiate:

$\mathrm{\&Sigma;}{\mathrm{\&Theta;}}_i(H_i-h_i\cos {\mathrm{\&theta;}}_i)\&GreaterEqual;5\frac{\mathrm{\&Sigma;M}}{n},$ If satisfy condition, then enter next step;

In the formula, i represents the i layer cap rock between reservoir space up-and-down boundary and the water-bearing zone; Θ represents rock stratum sealing ability adjustment coefficient; H represents the cap rock original thickness; H represents the turn-off of tomography in cap rock; θ represents co-hade; ∑ M represents seam mining thickness; N represents to exploit hierarchy number.

5. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, it is characterized in that: among the described step S5, use following formula to calculate and adopt ground settlement basin, stable region volume:

$V_3=\underset{\mathrm{\&Sigma;}}{\&Integral;\&Integral;}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\&Integral;\&Integral;}\sqrt{1+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;x}\right)}^2+{\left(\frac{{\&PartialD;S}_{A(x,y)}}{\&PartialD;y}\right)}^2}\mathrm{dxdy},$

$S_{A(x,y)}=\sqrt{{U_A}^2+{W_A}^2}$

$=\mathrm{m\&eta;}\cos \mathrm{\&alpha;}{\left(\begin{array}{c}\frac{{\mathrm{\&pi;b}}^6{(e^{\frac{\mathrm{\&pi;}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\&pi;x}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\&pi;}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\&pi;}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2},$

In the formula, S _{A (x, y)}The comprehensive displacement of earth's surface, stable region arbitrfary point A is adopted in expression; M represents that the coal seam adopts thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor,

U _MaxExpression earth's surface maximum horizontal movement value; W _MaxThe maximum vertically sinking in expression earth's surface; r ₁, r ₂, r ₃Expression move towards direction, go up a hill and the go down the hill major effect radius of direction, r ₁=H ₁/ tg β, r ₂=H ₂/ tg β, r ₃=H ₃/ tg β; Tg β represents major effect angle tangent; H ₁, H ₂, H ₃The expression workplace moves towards, goes up a hill and adopt deeply on the border of going down the hill; l ₁, l ₂The exploitation length of expression workplace on the strike and across strike.

6. the appraisal procedure of the moving stable region of Coal Exploitation according to claim 1 coal-seam gas reserves is characterized in that: use underground goaf to bury the method for beam tube test among the described step S6 or the method for analogy experience value obtains to adopt free gas concentration in the stable region.

7. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, and it is characterized in that: residual gas content calculates in such a way among the described step S7:

When not having the field survey data, the remaining coal bed gas content in the adjacent coal seam is calculated with the gas pressure relief amount of mine actual measurement adjacent coal seam air content deduction coal seam discharging, and computing formula is as follows:

q _i＝(1-η _i)q _i0

In the formula, q _I0Represent i adjacent layer primitive coalbed gas content; η _iRepresent i adjacent layer coal-seam gas discharging rate;

When working seam mining height during less than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_I=1-\frac{h_i}{h_p}$

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; h _pExpression is subjected to the formation of mining influence adjoining rock to run through the crack, and adjacent layer discharges the formation damage scope of pressure released seam gas to workplace.

When working seam mining height during greater than 4.5m, η _iBe calculated as follows:

${\mathrm{\&eta;}}_i=100-\frac{{0.47h}_i}{M}-\frac{84.04h_i}{L}$

In the formula, h _iRepresent i adjacent layer and mined bed vertical range; M represents mined bed workplace mining height; L represents the mined bed face length.

8. Coal Exploitation according to claim 1 moves the appraisal procedure of stable region coal-seam gas reserves, and it is characterized in that: the estimation of adopting stable region coal-seam gas reserves among the described step S8 utilizes respectively single coal bed or coal seam group computation model to finish according to the condition difference:

1. ought adopt the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

2. ought adopt the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

9. the evaluating system of the moving stable region of Coal Exploitation according to claim 1 coal-seam gas reserves is characterized in that: comprise stope essential information acquisition module, the effective relief range computing module of face surrounding rock, coal-seam gas reserve estimate model service condition discrimination module, face surrounding rock voidage computing module, Reserves Assessment model key parameter preferred module, adopt stable region Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module is used for obtaining stope size, buried depth, roof and floor lithologic distributed intelligence;

The effective relief range computing module of described face surrounding rock is used for obtaining stope roof and floor release height and width;

Described coal-seam gas reserve estimate model service condition discrimination module is used for whether applicable target stope Reserves Assessment of judgment models, if applicable then automatically enter next step, if inapplicable, then gives a warning;

Described face surrounding rock voidage computing module is used for calculating the space cumulative volume that obtains in the stope release country rock;

Described Reserves Assessment model key parameter preferred module is used for obtaining stope and leaves over coal resources, residual coal bed gas content, face surrounding rock crack coal-seam gas concentration;

The described stable region Coal-bed Gas Reserves of adopting is calculated module, is used for calculating and obtains the coal-seam gas reserves.

10. Coal Exploitation according to claim 9 moves the evaluating system of stable region coal-seam gas reserves, it is characterized in that: the described stable region Coal-bed Gas Reserves calculation module of adopting comprises single coal bed computing module and coal seam group computing module;

Described single coal bed computing module, being used for when adopting the coal seam, stable region is single coal bed, when not having other coal seams except working seam in adopting relief range, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV},$

Described coal seam group computing module, being used for when adopting the coal seam, stable region is coal seam group, adopts when also having other coal seams in the relief range except working seam, utilizes following formula to finish Reserves Assessment and calculates:

$\stackrel{\&OverBar;}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\&Sigma;}(1-{\mathrm{\&eta;}}_i)M_{i0}{q}_{i0}$

In the formula, M ₁Expression is adopted and is left over the coal total amount in the stable region; q ₁Expression is adopted and is lost the coal gas remainder quantity in the stable region; N represents to adopt coal-seam gas volume fraction in the stable region; V represents to adopt the stable region void volume; M _I0Represent i adjacent layer coal total amount; q _I0Represent the original gas bearing capacity of i adjacent layer; η _iExpression different layers spacing the next layer gas emission index.

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