CN103323887B - Method and system for evaluating coal bed gas reserve of coal mining stable area - Google Patents

Abstract

The invention discloses an evaluation and calculation method for coal bed gas reserves in a coal mining stable area, which comprises the following steps: 1) obtaining an effective pressure relief range of a mining stable area; 2) judging the applicable condition of the estimation model; 3) calculating the pore volume of surrounding rock in the mining stable area; 4) obtaining the concentration of free gas in a mining stable area; 5) estimating the residual coal quantity and the residual gas content in the mining stable area; 6) and finishing the estimation of the coal bed gas reserve in the mining stable area. The method comprises the steps of obtaining a total amount of free coal bed gas in the mining stable area, calculating the volume of surrounding rock gaps, and investigating the concentration of free gas, wherein the investigation of the effective pressure relief range of the mining stable area can determine the estimation boundary range of the coal bed gas reserves in the mining stable area, the judgment of the application conditions of an estimation model can select the effective estimation area, the accuracy of the estimation result is ensured, the total amount of the free coal bed gas in the mining stable area can be accurately estimated through the calculation of the surrounding rock void volume and the investigation of the concentration of the free gas, and the total amount of the adsorbed coal bed gas in the mining.

Description

The appraisal procedure of a kind of Coal Exploitation Dynamic stability district coal-seam gas reserves and system

Technical field

The invention belongs to coal field ground coal bed gas extraction technical field, relate to the coal-seam gas Reserves Assessment before surface well extraction Coal Exploitation Dynamic stability district coal-seam gas and calculate.

Background technology

Due to the restriction by coal winning method, technique and equipment, during seam mining, the rate of extraction cannot reach 100%, float coal residual a large amount of in goaf.Meanwhile, also there is certain thickness coal column in gob edge, and the methane desorb of float coal and coal column causes in goaf the coal-seam gas gathered and have higher concentration.In addition, the coal seam within the scope of mining effect also will enter goaf by mining-induced fissure by the pressure released seam gas produced after mining influence.If left, these coal-seam gas remain in underground, on the one hand, serious energy dissipation can be caused, the production safety of other contiguous mining face under mine can be threatened simultaneously, on the other hand, it can be overflowed earth's surface by mining-induced fissure, seriously affects terrestrial climate and ecologic environment, therefore needs to carry out coal-seam gas extraction to goaf or the old lane closed.

Extracting coal bed gas in stable mining region by ground well drilling technology is a kind of new cbm development mode that Later development gets up the nineties in 20th century, mainly on ground, coal mine gob again drilling well, adopt the method for negative pressure extraction, the coal-seam gas remained in the underground space, rock stratum and coal seam is extracted also from the coal mine of scrapping (stopping adopting).This technology both can make full use 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, strenuous exercise's phase of superincumbent stratum can be avoided again in time, thus realize the maximization of ground well drainage operation life, gas in goaf so both can have been stoped to gush out to contiguous workplace, extraction in time can go out a large amount of clear energy sources again, meet the scientific idea of current " low-carbon environment-friendly doctrine ".

Because surface drilling construction cost is higher, therefore the comparative analysis of economic interests is also absolutely necessary, this just needs the minimum mash gas extraction total amount estimating ground drilling in advance, no matter but at home and abroad colliery circle, how accurately to estimate in goaf and can remain a great problem of rig-site utilization at present by mash gas extraction reserves.Therefore, carry out adopting Dynamic stability district coalbed methane ground extraction key technology research, can play a role at national coal field gas pumping development field as soon as possible, become a difficult problem urgently to be resolved hurrily.

Summary of the invention

In view of this, technical matters to be solved by this invention is to provide a kind of method accurately can estimating Coal Exploitation Dynamic stability district coal-seam gas reserves, estimation to Coal Exploitation Dynamic stability district coal bed gas resource reserves is realized, for the feasibility study of target area cbm development and scale of investment design provide judging basis by the method.

An object of the present invention is the appraisal procedure proposing a kind of Coal Exploitation Dynamic stability district coal-seam gas reserves; Two of object of the present invention is the evaluating systems proposing a kind of Coal Exploitation Dynamic stability district coal-seam gas reserves.

An object of the present invention is achieved through the following technical solutions:

The appraisal procedure of a kind of Coal Exploitation Dynamic stability district provided by the invention coal-seam gas reserves, comprises the following steps:

S1: obtain need estimate coal-seam gas reserves adopt Dynamic stability district boundary condition, digging tunnel dispose and working face extraction technique information;

S2: obtain and need estimate that adopt the Dynamic stability paneling coal seam basic condition and adjoining rock lithology and tax thereof of coal-seam gas reserves deposit distribution characteristics;

S3: obtain the destruction release height adopting Dynamic stability district adjoining rock, the degree of depth and the release angle that need estimate coal-seam gas reserves;

S4: carry out the differentiation of model applicable elements, calculates and adopts the effective cover thickness in Dynamic stability district, differentiates that whether adopt Dynamic stability district sealing meets default basic criterion, presets basic criterion if met, then enters next step S5;

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

S6: obtain and adopt free gas concentration in Dynamic stability district;

S7: estimation is adopted in Dynamic stability district and lost coal amount and residual gas content thereof;

S8: bring the key parameter that step S3, S5, S6, S7 obtain into Reserves Assessment system, complete and adopt Dynamic stability district coal-seam gas reserve estimate;

S9: judge that whether adopt Dynamic stability district coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting coal seam, Dynamic stability district; If not, then gas pumping is stopped to adopting coal seam, Dynamic stability district.

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

Further, in described step S3, utilize adopting moving boundary angle to estimate and adopting Dynamic stability district roof strata release angle, larger than the boundary angle under corresponding conditions 4 ~ 10 ° of roof strata release angle of three times coal minings " three band opinions "; Utilize the release angle of up-protective layer Depressurized mining theory to estimate and adopt Dynamic stability district floor strata release angle, leak hunting test or testing laboratory numerical experiments of described use down-hole segmentation sealing of hole water filling is investigated verification and is adopted Dynamic stability district roof and floor relief range.

Further, in described step S4, when adopt in Dynamic stability district adjoining rock compose have strong aquifer time, use following formula complete model applicable elements differentiate:

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

In formula, i represents i-th layer of cap rock between reservoir space up-and-down boundary and water-bearing zone; Θ represents rock seal capacity adjusting coefficient; H represents 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 exploitation hierarchy number.

Further, in described step S5, following formulae discovery is used to adopt ground settlement basin, Dynamic stability district volume:

$V_3=\underset{\mathrm{\Σ}}{\∫\∫}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\∫\∫}\sqrt{1+{\left(\frac{{\∂S}_{A(x,y)}}{\∂x}\right)}^2+{\left(\frac{{\∂S}_{A(x,y)}}{\∂y}\right)}^2}\mathrm{dxdy},$

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

$=\mathrm{m\η}\cos \mathrm{\α}{\left(\begin{array}{c}\frac{{\mathrm{\πb}}^6{(e^{\frac{\mathrm{\π}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\πx}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2},$

In formula, S _{a (x, y)}represent the comprehensive displacement adopting arbitrfary point, earth's surface, Dynamic stability district A; M represents that coal seam is adopted thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor, u _maxrepresent earth's surface maximum horizontal movement value; W _maxrepresent the maximum vertical sinking in earth's surface; r ₁, r ₂, r ₃represent and move towards direction, go up a hill and the major effect radius in direction of going down the hill, 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 ₃represent that workplace moves towards, go up a hill and border of going down the hill is adopted deeply; l ₁, l ₂represent the exploitation length of workplace on the strike and across strike.

Further, the method for the method or analogy experience value that use underground goaf to bury beam tube test in described step S6 obtains adopts free gas concentration in Dynamic stability district.

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

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

q _i＝(1-η _i)q _i0

In formula, q _i0represent the i-th adjacent layer primitive coalbed Gas content; η _irepresent the i-th adjacent layer coal-seam gas emission index;

When working seam mining height is less than 4.5m, η _ibe calculated as follows:

${\mathrm{\η}}_i=1-\frac{h_i}{h_p}$ p

In formula, h _irepresent the i-th adjacent layer and mined bed vertical range; h _pexpression is formed by mining influence adjoining rock and runs through crack, and adjacent layer is to the formation damage scope of workplace release pressure released seam gas.

When working seam mining height is greater than 4.5m, η _ibe calculated as follows:

${\mathrm{\η}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

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

Further, the estimation of described step S8 Zhong Cai Dynamic stability district coal-seam gas reserves utilizes single coal bed or coal seam group computation model to complete according to condition difference respectively:

1. be single coal bed when adopting coal seam, Dynamic stability district, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV},$

2. being coal seam group when adopting coal seam, Dynamic stability district, adopting when also there are other coal seams in relief range except working seam, utilizing following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district void volume; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index.

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

The evaluating system of a kind of Coal Exploitation Dynamic stability district 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 Dynamic stability district Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module, for obtaining Stope dimension, buried depth, roof and floor lithologic distributed intelligence;

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

Whether described coal-seam gas reserve estimate model service condition discrimination module, be suitable for target stope Reserves Assessment for judgment models, if be suitable for, automatically entered next step, if inapplicable, then give a warning;

Described face surrounding rock voidage computing module, for calculating the space cumulative volume obtained in stope release country rock;

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

Described Dynamic stability district Coal-bed Gas Reserves of adopting calculates module, obtains coal-seam gas reserves for calculating;

Further, adopt Dynamic stability district Coal-bed Gas Reserves calculation module described in and comprise single coal bed computing module and coal seam group computing module;

Described single coal bed computing module, for when to adopt coal seam, Dynamic stability district be single coal bed, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV},$

Described coal seam group computing module, for when to adopt coal seam, Dynamic stability district be coal seam group, adopt when also there are other coal seams in relief range except working seam, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district void volume; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index.

The invention has the advantages that: provided by the inventionly adopt Dynamic stability district coal bed gas resource Reserves Assessment method, what construct single coal bed mining conditions and coal seam group mining condition respectively adopts Dynamic stability district coal-seam gas reserve estimate model, model not only considers the release effect of subterranean coal exploitation to exploiting field roof and floor country rock, the investigation of adopting the effective relief range in Dynamic stability district can be determined to adopt Dynamic stability district coal-seam gas reserve estimate bounds, wherein, appraising model applicable elements differentiates can select effective estimation area, ensure the accuracy of estimation result, country rock voidage calculate and free gas concentration investigate can more accurately estimate adopt in Dynamic stability district dissociate coal-seam gas total amount, adopt in Dynamic stability district and lose coal amount and residual gas Content inspect thereof and more accurately can estimate and adopt absorption coal-seam gas total amount Dynamic stability district in, also contemplate working face extraction technique, tunnel is disposed, enclosing lithologies and ground settlement are on the impact of stope fractured zones, the coal bed gas resource reserves in Coal Exploitation Dynamic stability district can be estimated accurately, for the feasibility study of target area cbm development and scale of investment design provide decision-making foundation.

Accompanying drawing explanation

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

Fig. 1 shows the effective relief range schematic diagram of Coal Exploitation Dynamic stability district country rock;

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 beam tube investigation minery;

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

Fig. 5 shows Coal Exploitation Dynamic stability district coal-seam gas estimation method of reserve schematic flow sheet;

Fig. 6 shows Coal Exploitation Dynamic stability district 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 in order to the present invention is described, instead of in order to limit the scope of the invention.

Embodiment 1

Fig. 1 shows the effective relief range schematic diagram of Coal Exploitation Dynamic stability district country rock; In figure, 1 is coal seam goaf, and 2 is working seam, and 3 is the visual distressed zone (bedseparated fissures development area) of goaf roof and floor country rock, 4 is not visible effective distressed zone (microfissure development area) of goaf roof and floor country rock, and 5 is the transition distressed zone of roof and floor country rock.In figure, 1,3,4 is the main assessment objective region of evaluating system, 5 due to the unload effects be subject to less, be not enough to make coal-seam gas in its peripheral coal rock layer by this region, define the border in assessment objective region.

Fig. 2 shows down-hole segmentation sealing of hole water filling test schematic diagram; In figure, 6 is working seam, and 7 is observation chamber, and 8 is observation boring, and 9 is water guide (gas) fissure zone, and 10 is roof caving band.To construct in roof in down-hole the boring at any elevation angle, carry out note (putting) water of differentiated manner, can judge according to note (putting) water yield effective release drainage maximum height of affecting by recovery activity, matching can obtain effective release border in assessment objective region (Ji Cai Dynamic stability district) by multiple Test Point Data.

Fig. 3 shows underground goaf and buries coal-seam gas concentration schematic diagram in beam tube investigation minery; Time near the advance of the face to monitoring point, after coalcutter support, lay beam tube, lay 3 beam tubes, first beam tube distance, second beam tube 150m, second beam tube distance the 3rd beam tube 100m.4 ~ 5 sampling spots arranged by every root beam tube, and each sampling spot spacing 40 ~ 50m, sampling spot numbering situation is shown in diagram.All beam tubes all pass from protective casing (steel pipe); protective casing is imbedded below float coal, and built-in pipe adopts diameter 2 cun of steel pipes, penetrates the beam tube of 4 ~ 5 ф 8mm/12mm different colours wherein; the gas sample of a measuring point is responsible for by every root beam tube, and each sampling head raises more than 0.5m.The sampling head of each beam tube at the protection downward-extension of sleeve pipe, can adopt and stay the mode of establishing boring at fire dam place, drilling design diameter 60 ㎜ to crossheading fire dam.Confirm whole beam tube and contact place No leakage, after workplace pushes away beam tube 20m, regularly (4 ~ 5 days/time) carry out gas sample to each beam tube.Gas sample should be carried out during infrabar, namely between at 2 to 4 in afternoon.Before carrying out gas sample, gas sample draw-off pump should be connected and run 5 ~ 10 minutes, discharging bundle inner air tube, to ensure to gather gas sample from measuring point place, goaf.

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

Fig. 5 shows Coal Exploitation Dynamic stability district coal-seam gas estimation method of reserve schematic flow sheet, Fig. 6 shows Coal Exploitation Dynamic stability district coal-seam gas reserve estimate system architecture schematic diagram, as shown in the figure: the appraisal procedure of a kind of Coal Exploitation Dynamic stability district provided by the invention coal-seam gas reserves, comprises the following steps:

S1: obtain need estimate coal-seam gas reserves adopt Dynamic stability district boundary condition, digging tunnel dispose and working face extraction technique information;

S2: obtain and need estimate that adopt the Dynamic stability paneling coal seam basic condition and adjoining rock lithology and tax thereof of coal-seam gas reserves deposit distribution characteristics;

S3: obtain the destruction release height adopting Dynamic stability district adjoining rock, the degree of depth and the release angle that need estimate coal-seam gas reserves;

S4: carry out the differentiation of model applicable elements, calculates and adopts the effective cover thickness in Dynamic stability district, differentiates that whether adopt Dynamic stability district sealing meets default basic criterion, presets basic criterion if met, then enters next step S5;

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

S6: obtain and adopt free gas concentration in Dynamic stability district;

S7: estimation is adopted in Dynamic stability district and lost coal amount and residual gas content thereof;

S8: bring the key parameter that step S3, S5, S6, S7 obtain into Reserves Assessment system, complete and adopt Dynamic stability district coal-seam gas reserve estimate;

S9: judge that whether adopt Dynamic stability district coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting coal seam, Dynamic stability district; If not, then gas pumping is stopped to adopting coal seam, Dynamic stability district.

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

In described step S3, utilize adopting moving boundary angle to estimate and adopting Dynamic stability district roof strata release angle, larger than the boundary angle under corresponding conditions 4 ~ 10 ° of roof strata release angle of three times coal minings " three band opinions "; Utilize the release angle of up-protective layer Depressurized mining theory to estimate and adopt Dynamic stability district floor strata release angle, leak hunting test or testing laboratory numerical experiments of described use down-hole segmentation sealing of hole water filling is investigated verification and is adopted Dynamic stability district roof and floor relief range.

In described step S4, when adopt in Dynamic stability district adjoining rock compose have strong aquifer time, use following formula complete model applicable elements differentiate:

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

In formula, i represents i-th layer of cap rock between reservoir space up-and-down boundary and water-bearing zone; Θ represents rock seal capacity adjusting coefficient; H represents 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 exploitation hierarchy number.

In described step S5, following formulae discovery is used to adopt ground settlement basin, Dynamic stability district volume:

$V_3=\underset{\mathrm{\Σ}}{\∫\∫}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\∫\∫}\sqrt{1+{\left(\frac{{\∂S}_{A(x,y)}}{\∂x}\right)}^2+{\left(\frac{{\∂S}_{A(x,y)}}{\∂y}\right)}^2}\mathrm{dxdy},$

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

$=\mathrm{m\η}\cos \mathrm{\α}{\left(\begin{array}{c}\frac{{\mathrm{\πb}}^6{(e^{\frac{\mathrm{\π}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\πx}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2},$

In formula, S _{a (x, y)}represent the comprehensive displacement adopting arbitrfary point, earth's surface, Dynamic stability district A; M represents that coal seam is adopted thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor, u _maxrepresent earth's surface maximum horizontal movement value; W _maxrepresent the maximum vertical sinking in earth's surface; r ₁, r ₂, r ₃represent and move towards direction, go up a hill and the major effect radius in direction of going down the hill, 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 ₃represent that workplace moves towards, go up a hill and border of going down the hill is adopted deeply; l ₁, l ₂represent the exploitation length of workplace on the strike and across strike.

The method of the method or analogy experience value that use underground goaf to bury beam tube test in described step S6 obtains adopts free gas concentration in Dynamic stability district.

In described step S7, residual gas content calculates in such a way:

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

q _i＝(1-η _i)q _i0

In formula, q _i0represent the i-th adjacent layer primitive coalbed Gas content; η _irepresent the i-th adjacent layer coal-seam gas emission index;

When working seam mining height is less than 4.5m, η _ibe calculated as follows:

${\mathrm{\η}}_i=1-\frac{h_i}{h_p}$

In formula, h _irepresent the i-th adjacent layer and mined bed vertical range; h _pexpression is formed by mining influence adjoining rock and runs through crack, and adjacent layer is to the formation damage scope of workplace release pressure released seam gas.

When working seam mining height is greater than 4.5m, η _ibe calculated as follows:

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

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

The estimation of described step S8 Zhong Cai Dynamic stability district coal-seam gas reserves utilizes single coal bed or coal seam group computation model to complete according to condition difference respectively:

1. be single coal bed when adopting coal seam, Dynamic stability district, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV},$

2. being coal seam group when adopting coal seam, Dynamic stability district, adopting when also there are other coal seams in relief range except working seam, utilizing following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district void volume; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index.

The present embodiment additionally provides the evaluating system of a kind of Coal Exploitation Dynamic stability district 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 Dynamic stability district Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module, for obtaining Stope dimension, buried depth, roof and floor lithologic distributed intelligence;

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

Whether described coal-seam gas reserve estimate model service condition discrimination module, be suitable for target stope Reserves Assessment for judgment models, if be suitable for, automatically entered next step, if inapplicable, then give a warning;

Described face surrounding rock voidage computing module, for calculating the space cumulative volume obtained in stope release country rock;

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

Described Dynamic stability district Coal-bed Gas Reserves of adopting calculates module, obtains coal-seam gas reserves for calculating;

Described Dynamic stability district 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, for when to adopt coal seam, Dynamic stability district be single coal bed, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV},$

Described coal seam group computing module, for when to adopt coal seam, Dynamic stability district be coal seam group, adopt when also there are other coal seams in relief range except working seam, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district void volume; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index.

Embodiment 2

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

The present embodiment 2 provides the appraisal procedure of a kind of Coal Exploitation Dynamic stability district coal-seam gas reserves, comprises the following steps:

1) obtain need estimate coal-seam gas reserves adopt Dynamic stability district boundary condition, digging tunnel disposes and the information such as working face extraction technique;

2) acquisition need estimate that adopt the Dynamic stability paneling coal seam basic condition and adjoining rock lithology and tax thereof of coal-seam gas reserves deposit distribution characteristics;

3) the destruction release height adopting Dynamic stability district adjoining rock, the degree of depth and the release angle that need estimate coal-seam gas reserves is obtained;

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

5) acquisition adopts ground settlement basin, Dynamic stability district volume, calculation stability district country rock volume of voids;

6) free gas concentration in Dynamic stability district is adopted in acquisition;

7) estimation is adopted in Dynamic stability district and is lost coal amount and residual gas content thereof;

8) each key parameter is substituted into system, complete Coal Seams on Infection Zones of Coal Mining gas reserve estimate.

In described step 1), the range of application of assessment technology has been subject to seam mining impact, and affect the region, colliery stopped.

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

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

In the overlying strata of coal seam be hard, in hard, weakness, dead-soft incompetent beds or its alternating layers time, the leaking crevice belt maximum height of thick seam slicing system can select the formulae discovery in table 1.

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

Note: Σ M-accumulative adopts thick; The formula scope of application: individual layer adopts thick 1 ~ 3m, accumulative adopting thickly is no more than 15m; In computing formula ± number item is medial error.

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

Top, coal seam, base plate be hard, in hard, soft stratum, the formulae discovery in the height of the water conductive fracture zone free list 2 when exploiting with caving method.

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

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

3. during exploitation coal seam group with near interval, height of the water conductive fracture zone calculates

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

When the caving zone of b \ lower floor coal touches or enters day-coal completely, the leaking crevice belt maximum height of day-coal presses the THICKNESS CALCULATION of this layer of coal, the leaking crevice belt maximum height of lower floor's coal then adopts the comprehensive mining high computational of upper and lower layer coal, if 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 leaking crevice belt maximum height of two-layer coal.

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

In formula, h _1-2normal distance between-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 gets the thick sum of two-layer coal to c.After obtaining comprehensive mining thickness, caving zone height when can exploit 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 mutil-coal seam mining condition.

4. base plate release depth calculation

In 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 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 described step 3), what utilize three times coal minings " three band opinions " adopts moving boundary angle to estimate target area roof strata release angle, larger than the boundary angle under corresponding conditions 4 ~ 10 ° of roof strata release angle; Utilize estimation target area, the release angle floor strata release angle of up-protective layer Depressurized mining theory.

In 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 described step 4), when adopt in Dynamic stability district adjoining rock compose have strong aquifer time, use following formula complete model applicable elements differentiate.

$\mathrm{\Σ}{\mathrm{\Θ}}_i(H_i-h_i\cos {\mathrm{\θ}}_i)\≥5\frac{\mathrm{\ΣM}}{n}$

In formula, i-th layer of cap rock of i-between reservoir space up-and-down boundary and water-bearing zone; Θ-rock seal capacity adjusting 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.

Following table 3 is used to determine coal field common lithology rock seal capacity factor Θ.

Table 3 coal field common lithology rock seal capacity factor table

In described step 5), following formulae discovery is used to adopt ground settlement basin, Dynamic stability district volume.

$V_3=\underset{\mathrm{\Σ}}{\∫\∫}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\∫\∫}\sqrt{1+{\left(\frac{{\∂S}_{A(x,y)}}{\∂x}\right)}^2+{\left(\frac{{\∂S}_{A(x,y)}}{\∂y}\right)}^2}\mathrm{dxdy}$

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

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

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

$=\mathrm{m\η}\cos \mathrm{\α}{\left(\begin{array}{c}\frac{{\mathrm{\πb}}^6{(e^{\frac{\mathrm{\π}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\πx}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2}$

In 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 vertical sinking in-earth's surface; R1, r2, r3-move towards direction, to go up a hill and the major effect radius in direction of going 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, go up a hill and border of going down the hill is adopted deeply, m; The exploitation length of l1, l2-workplace on the strike and across strike, m.

In described step 6), the method for the method or analogy experience value that use underground goaf to bury beam tube test obtains adopts free gas concentration in Dynamic stability district.

In described step 7), when not having field survey data, the remaining coal bed gas content in adjacent coal seam can survey the gas pressure relief gauge calculation of adjacent coal seam air content deduction coal seam discharge with mine, computing formula is as follows:

q _i＝(1-η _i)q _i0

In formula, qi0-the i-th adjacent layer primitive coalbed Gas content, m3/t; η _i-the i-th adjacent layer coal-seam gas emission index, %.

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

${\mathrm{\η}}_i=1-\frac{h_i}{h_p}$

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

When working seam mining height is greater than 4.5m, η _ibe calculated as follows.

${\mathrm{\η}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

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

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

1. single coal bed condition

Adopt in relief range except working seam, there are not other coal seams time, utilize following formula complete Reserves Assessment calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}$

2. coal seam group condition

When adopt in relief range except working seam, also there are other coal seams time, utilize following formula complete Reserves Assessment calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁-adopt in Dynamic stability district and leave over coal total amount, t; q ₁-adopt in Dynamic stability district and lose coal gas remainder quantity, m3/t; N-adopt coal-seam gas volume fraction in Dynamic stability district, %; V-adopt Dynamic stability district void volume, m3; Mi0-the i-th adjacent layer coal total amount, t; The original gas bearing capacity of qi0-the i-th 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 is only:

See the Coal Exploitation Dynamic stability district coal-seam gas estimation method of reserve of Fig. 5 the present embodiment 3, comprise the steps:

1) obtain need estimate the Coal Exploitation Dynamic stability district bounds of coal-seam gas reserves, the key message such as digging tunnel is disposed, working face extraction technique and exploiting field hydrogeological condition;

2) acquisition need estimate that adopt the Dynamic stability paneling coal seam basic condition and adjoining rock lithology and tax thereof of coal-seam gas reserves deposit distribution characteristics;

3) the destruction release height adopting Dynamic stability district adjoining rock, the degree of depth and the release angle that need estimate coal-seam gas reserves is obtained;

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

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 hard, weakness, dead-soft incompetent beds or its alternating layers time, the leaking crevice belt maximum height of thick seam slicing system can select the formulae discovery in table 7.

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

Note: Σ M-accumulative adopts thick; The formula scope of application: individual layer adopts thick 1 ~ 3m, accumulative adopting thickly is no more than 15m; In computing formula ± number item is medial error.

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

Top, coal seam, base plate be hard, in hard, soft stratum, the formulae discovery in the height of the water conductive fracture zone free list 8 when exploiting with caving method.

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

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

3. coal seam group with near interval destruction height is exploited

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

When the caving zone of b \ lower floor coal touches or enters day-coal completely, the leaking crevice belt maximum height of day-coal presses the THICKNESS CALCULATION of this layer of coal, the leaking crevice belt maximum height of lower floor's coal then adopts the comprehensive mining high computational of upper and lower layer coal, if 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 leaking crevice belt maximum height of two-layer coal.

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

In formula, h _1-2normal distance between-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 gets the thick sum of two-layer coal to c.After obtaining comprehensive mining thickness, caving zone height when can exploit 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 mutil-coal seam mining condition.

4. base plate release collapse dept calculates

In 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 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;

The release of ⑤Cai Dynamic stability district destroys boundary angles

What utilize three times coal minings " three band opinions " adopts moving boundary angle to estimate target area roof strata release angle, larger than the boundary angle under corresponding conditions 4 ~ 10 ° of roof strata release angle; Utilize estimation target area, the release angle floor strata release angle of up-protective layer Depressurized mining theory.

Secondly, see 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) combine obtain adopt Dynamic stability district adjoining rock destruction height and roof and floor lithologic distribution, hydrogeological characteristics, carry out the differentiation of model applicable elements, if meet basic criterion, enter next step; If do not meet this criterion of model-based, then need to seek additive method and complete estimation;

When adopt in Dynamic stability district adjoining rock do not compose have strong aquifer time, ignore this step; When adopt in Dynamic stability district adjoining rock compose have strong aquifer time, use following formula complete model applicable elements differentiate.

$\mathrm{\Σ}{\mathrm{\Θ}}_i(H_i-h_i\cos {\mathrm{\θ}}_i)\≥5\frac{\mathrm{\ΣM}}{n}$

In formula, i-th layer of cap rock of i-between reservoir space up-and-down boundary and water-bearing zone; Θ-rock seal capacity adjusting 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.

Following table 9 is used to determine coal field common lithology rock seal capacity factor Θ.

Table 9 coal field common lithology rock seal capacity factor table

5) acquisition adopts ground settlement basin, Dynamic stability district volume, calculation stability district country rock volume of voids;

Following formulae discovery is used to adopt ground settlement basin, Dynamic stability district volume.

$V_3=\underset{\mathrm{\Σ}}{\∫\∫}\mathrm{dS}=\underset{D_{\mathrm{xy}}}{\∫\∫}\sqrt{1+{\left(\frac{{\∂S}_{A(x,y)}}{\∂x}\right)}^2+{\left(\frac{{\∂S}_{A(x,y)}}{\∂y}\right)}^2}\mathrm{dxdy}$

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

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

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

$=\mathrm{m\η}\cos \mathrm{\α}{\left(\begin{array}{c}\frac{{\mathrm{\πb}}^6{(e^{\frac{\mathrm{\π}{(-x+l_1)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\πx}}^2}{{r_1}^2}})}^2{(\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{2\mathrm{\π}}y}{r_3}\right))}^2}{{{2r}_2}^2}+\\ \frac{{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-x+l_1)}{r_1}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}x}{r_1}\right))}^2{(\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}(-y+l_2)}{r_2}\right)+\mathrm{erf}\left(\frac{\sqrt{\mathrm{\π}}y}{r_3}\right))}^2}{16}\end{array}\right)}^{1/2}$

In 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 vertical sinking in-earth's surface; R1, r2, r3-move towards direction, to go up a hill and the major effect radius in direction of going 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, go up a hill and border of going down the hill is adopted deeply, m; The exploitation length of l1, l2-workplace on the strike and across strike, m.

6) see accompanying drawing 3, the method for the method or analogy experience value that use underground goaf to bury beam tube test obtains adopts free gas concentration in Dynamic stability district;

7) adopt in Dynamic stability district lose coal amount and residual gas content thereof according to Field Production Data estimation;

When not having field survey data, the remaining coal bed gas content in adjacent coal seam can survey the gas pressure relief gauge calculation of adjacent coal seam air content deduction coal seam discharge with mine, computing formula is as follows:

q _i＝(1-η _i)q _i0

In formula, qi0-the i-th adjacent layer primitive coalbed Gas content, m3/t; η _i-the i-th adjacent layer coal-seam gas emission index, %.

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

${\mathrm{\η}}_i=1-\frac{h_i}{h_p}$

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

When working seam mining height is greater than 4.5m, η _ibe calculated as follows.

${\mathrm{\η}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

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

8) each key parameter is substituted into computing system, complete Coal Seams on Infection Zones of Coal Mining gas reserve estimate.

See Fig. 6, the Dynamic stability district Coal-bed Gas Reserves of adopting of the present embodiment calculates system, comprising:

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

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

3. coal-seam gas reserve estimate model service condition discrimination module, judges whether this model is suitable for target stope Reserves Assessment, if be suitable for, automatically entered next step, if inapplicable, then gives a warning;

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

5. Reserves Assessment model key parameter You Xuan acquisition module, obtains stope and leaves over coal resources, the residual key parameter such as coal bed gas content, face surrounding rock crack coal-seam gas concentration;

⑥Cai Dynamic stability district Coal-bed Gas Reserves calculates module, calculates and obtains coal-seam gas reserves.

Adopt Dynamic stability district Coal-bed Gas Reserves calculation module and comprise two class computation models, the reserve estimate of single coal bed condition and coal seam group condition can be realized:

A single coal bed condition

Adopt in relief range except working seam, there are not other coal seams time, utilize following formula complete Reserves Assessment calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}$

B coal seam group condition

When adopt in relief range except working seam, also there are other coal seams time, utilize following formula complete Reserves Assessment calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+\mathrm{nV}+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, M ₁-adopt in Dynamic stability district and leave over coal total amount, t; q ₁-adopt in Dynamic stability district and lose coal gas remainder quantity, m3/t; N-adopt coal-seam gas volume fraction in Dynamic stability district, %; V-adopt Dynamic stability district void volume, m3; Mi0-the i-th adjacent layer coal total amount, t; The original gas bearing capacity of qi0-the i-th adjacent layer, m3/t; η i-different layers spacing the next layer gas emission index, %.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, obviously, those skilled in the art can carry out various change and modification to the present invention and not depart from the spirit and scope of the present invention.Like this, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

Claims (7)

1. an appraisal procedure for Coal Exploitation Dynamic stability district coal-seam gas reserves, is characterized in that: comprise the following steps:

S1: obtain need estimate coal-seam gas reserves adopt Dynamic stability district boundary condition, digging tunnel dispose and working face extraction technique information;

S2: obtain and need estimate that adopt the Dynamic stability paneling coal seam basic condition and adjoining rock lithology and tax thereof of coal-seam gas reserves deposit distribution characteristics;

S3: obtain the destruction release height adopting Dynamic stability district adjoining rock, the degree of depth and the release angle that need estimate coal-seam gas reserves;

S4: carry out the differentiation of model applicable elements, calculates and adopts the effective cover thickness in Dynamic stability district, differentiates that whether adopt Dynamic stability district sealing meets default basic criterion, presets basic criterion if met, then enters next step S5 by following method;

When adopt in Dynamic stability district adjoining rock do not compose have strong aquifer time, ignore this step; When adopt in Dynamic stability district adjoining rock compose have strong aquifer time, use following formula complete model applicable elements differentiate:

${\mathrm{\Σ\Θ}}_i(H_i-h_i{\mathrm{cos\θ}}_i)\≥5\frac{\mathrm{\Σ}M}{n}$

In formula, i represents i-th layer of cap rock between reservoir space up-and-down boundary and water-bearing zone; Θ represents rock seal capacity adjusting coefficient; H represents 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 exploitation hierarchy number;

S5: obtain and adopt ground settlement basin, Dynamic stability district volume, calculates and adopts Dynamic stability district country rock volume of voids;

S6: obtain and adopt free gas concentration in Dynamic stability district;

S7: estimation is adopted in Dynamic stability district and lost coal amount and residual gas content thereof;

S8: the parameter that step S3, S5, S6, S7 are obtained, comprise destruction release height, the degree of depth and the release angle of adopting Dynamic stability district adjoining rock, adopt ground settlement basin, Dynamic stability district volume, adopt Dynamic stability district country rock volume of voids, adopt free gas concentration in Dynamic stability district, adopt in Dynamic stability district and lose coal amount and residual gas content thereof;

Utilize single coal bed or coal seam group computation model to complete respectively according to condition difference and adopt Dynamic stability district coal-seam gas reserve estimate;

1. be single coal bed when adopting coal seam, Dynamic stability district, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+nV,$

2. being coal seam group when adopting coal seam, Dynamic stability district, adopting when also there are other coal seams in relief range except working seam, utilizing following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+nV+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, for adopting Dynamic stability district coal-seam gas reserves; M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district country rock volume of voids; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index;

S9: judge that whether adopt Dynamic stability district coal-seam gas reserves reaches minimum mash gas extraction total amount, if so, then carries out gas pumping to adopting coal seam, Dynamic stability district; If not, then gas pumping is stopped to adopting coal seam, Dynamic stability district.

2. the appraisal procedure of Coal Exploitation Dynamic stability district according to claim 1 coal-seam gas reserves, it is characterized in that: in described step S3, three times coal minings three are utilized to be with adopting moving boundary angle to estimate and adopting Dynamic stability district roof strata release angle, larger than the boundary angle under corresponding conditions 4 ~ 10 ° of roof strata release angle of opinions; Utilize the release angle of up-protective layer Depressurized mining theory to estimate and adopt Dynamic stability district floor strata release angle, use leak hunting test or testing laboratory's numerical experiments of down-hole segmentation sealing of hole water filling to investigate verification and adopt Dynamic stability district roof and floor relief range.

3. the appraisal procedure of Coal Exploitation Dynamic stability district according to claim 1 coal-seam gas reserves, is characterized in that: in described step S5, uses following formulae discovery to adopt ground settlement basin, Dynamic stability district volume V ₃:

$V_3=\underset{\mathrm{\Σ}}{\∫\∫}dS=\underset{D_{xy}}{\∫\∫}\sqrt{1+{\left(\frac{\∂S_{A(x,y)}}{\∂x}\right)}^2+{\left(\frac{\∂S_{A(x,y)}}{\∂y}\right)}^2}dxdy,$

$\begin{array}{c}{S}_{A\left(x,y\right)}=\sqrt{{U_A}^2+{W_A}^2}\\ =m\mathrm{\η}\cos \mathrm{\α}{\left(\begin{array}{c}\frac{{\mathrm{\πb}}^6{\left(e^{-\frac{\mathrm{\π}{\left(-x+l_1\right)}^2}{{r_1}^2}}-e^{-\frac{{\mathrm{\πx}}^2}{{r_1}^2}}\right)}^2{\left(erf\left(\frac{\sqrt{2\mathrm{\π}}\left(-y+l_2\right)}{r_2}\right)+erf\left(\frac{\sqrt{2\mathrm{\π}}y}{r_3}\right)\right)}^2}{2{r_2}^2}+\\ \frac{{\left(erf\left(\frac{\sqrt{\mathrm{\π}}\left(-x+l_1\right)}{r_1}\right)+erf\left(\frac{\sqrt{\mathrm{\π}}x}{r_1}\right)\right)}^2{\left(erf\left(\frac{\sqrt{\mathrm{\π}}\left(-y+l_2\right)}{r_2}\right)+erf\left(\frac{\sqrt{\mathrm{\π}}y}{r_3}\right)\right)}^2}{16}\end{array}\right)}^{1/2}\end{array},$

In formula, S _{a (x, y)}represent the comprehensive displacement adopting arbitrfary point, earth's surface, Dynamic stability district A; U _afor the horizontal movement value of arbitrfary point, earth's surface A; W _afor the vertical sinking of arbitrfary point, earth's surface A; M represents that coal seam is adopted thick; η represents subsidence factor; α represents seam inclination; B represents displacement factor, u _maxrepresent earth's surface maximum horizontal movement value; W _maxrepresent the maximum vertical sinking in earth's surface; r ₁, r ₂, r ₃represent and move towards direction, go up a hill and the major effect radius in direction of going down the hill, 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 ₃represent that workplace moves towards, go up a hill and border of going down the hill is adopted deeply; l ₁, l ₂represent the exploitation length of workplace on the strike and across strike.

4. the appraisal procedure of Coal Exploitation Dynamic stability district according to claim 1 coal-seam gas reserves, is characterized in that: the method for the method or analogy experience value that use underground goaf to bury beam tube test in described step S6 obtains adopts free gas concentration in Dynamic stability district.

5. the appraisal procedure of Coal Exploitation Dynamic stability district according to claim 1 coal-seam gas reserves, is characterized in that: in described step S7, residual gas content calculates in such a way:

When there is no field survey data, the remaining coal bed gas content q in adjacent coal seam _icalculate with the gas pressure relief gauge of mine actual measurement adjacent coal seam air content deduction coal seam discharge, computing formula is as follows:

q _i＝(1-η _i)q _i0

In formula, q _i0represent the i-th adjacent layer primitive coalbed Gas content; η _irepresent the i-th adjacent layer coal-seam gas emission index;

When working seam mining height is less than 4.5m, η _ibe calculated as follows:

${\mathrm{\η}}_i=1-\frac{h_i}{h_p}$

In formula, h _irepresent the i-th adjacent layer and mined bed vertical range; h _pexpression is formed by mining influence adjoining rock and runs through crack, and adjacent layer is to the formation damage scope of workplace release pressure released seam gas;

When working seam mining height is greater than 4.5m, η _ibe calculated as follows:

${\mathrm{\η}}_i=100-\frac{0.47h_i}{M}-\frac{84.04h_i}{L}$

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

6. adopt the appraisal procedure of the Coal Exploitation Dynamic stability district coal-seam gas reserves described in claim 1-5 any one to carry out the evaluating system of the Coal Exploitation Dynamic stability district coal-seam gas reserves assessed, it 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, adopt Dynamic stability district country rock volume of voids computing module, Reserves Assessment model key parameter preferred module, adopt Dynamic stability district Coal-bed Gas Reserves calculation module;

Described stope essential information acquisition module, for obtaining Stope dimension, buried depth, roof and floor lithologic distributed intelligence;

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

Whether described coal-seam gas reserve estimate model service condition discrimination module, be suitable for target stope Reserves Assessment for judgment models, if be suitable for, automatically entered next step, if inapplicable, then give a warning;

Describedly adopt Dynamic stability district country rock volume of voids computing module, for calculating the space cumulative volume obtained in stope release country rock;

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

Described Dynamic stability district Coal-bed Gas Reserves of adopting calculates module, obtains coal-seam gas reserves for calculating.

7. the evaluating system of Coal Exploitation Dynamic stability district according to claim 6 coal-seam gas reserves, is characterized in that: described in adopt Dynamic stability district Coal-bed Gas Reserves and calculate module and comprise single coal bed computing module and coal seam group computing module;

Described single coal bed computing module, for when to adopt coal seam, Dynamic stability district be single coal bed, adopt in relief range except working seam, there are not other coal seams time, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+nV,$

Described coal seam group computing module, for when to adopt coal seam, Dynamic stability district be coal seam group, adopt when also there are other coal seams in relief range except working seam, utilize following formula to complete Reserves Assessment and calculate:

$\stackrel{\‾}{Q}=M_1{q}_1+nV+\mathrm{\Σ}(1-{\mathrm{\η}}_i)M_{i0}{q}_{i0}$

In formula, for adopting Dynamic stability district coal-seam gas reserves; M ₁represent to adopt in Dynamic stability district and leave over coal total amount; q ₁represent to adopt in Dynamic stability district and lose coal gas remainder quantity; N represents and adopts coal-seam gas volume fraction in Dynamic stability district; V represents and adopts Dynamic stability district country rock volume of voids; M _i0represent the i-th adjacent layer coal total amount; q _i0represent the original gas bearing capacity of the i-th adjacent layer; η _irepresent different layers spacing the next layer gas emission index.