Application and Development of an Environmentally Friendly Blast Hole Plug for Underground Coal Mines

<table class="fixed-width table-group" id="tab4"><tr><td><table class="table"><colgroup><col style="width:5.74em"/><col style="width:6.85em"/><col style="width:6.85em"/><col style="width:7.96em"/><col style="width:9.08em"/><col style="width:9.08em"/><col style="width:6.85em"/><col style="width:11.31em"/></colgroup><tr><td class="thead-hr" colspan="8"><hr/></td></tr><tr class="thead"><td class="align_left">Name</td><td class="align_center">Properties</td><td class="align_center">Section shape</td><td class="align_center">Lithology</td><td class="align_center">Dimensions <br/><svg height="13.8595pt" id="M16" style="vertical-align:-2.2681pt" version="1.1" viewbox="-0.0498162 -11.5914 67.058 13.8595" width="67.058pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M962 650H739L732 622L760 619C812 613 819 604 798 552C760 457 671 267 606 131H604L511 638H480L237 131H233L183 554C177 607 183 614 226 619L248 622L257 650H24L17 622C88 615 92 611 103 524L173 -11H203L450 491H453L543 -11H575L839 529C882 609 886 613 953 622L962 650Z" id="g113-88"></path></g><g transform="matrix(.013,0,0,-0.013,20.073,0)"><path d="M528 54L331 254L528 455L492 493L294 291L96 493L60 455L257 254L60 54L96 16L294 217L492 16L528 54Z" id="g117-42"></path></g><g transform="matrix(.013,0,0,-0.013,30.609,0)"><path d="M828 650H570L564 622C646 614 650 609 634 524L604 366H253L281 524C296 608 308 615 382 622L388 650H132L126 622C211 615 214 609 198 524L121 122C106 42 102 35 23 28L17 0H276L282 28C196 35 191 40 206 122L243 324H597L559 123C544 42 537 35 452 28L446 0H710L716 28C632 35 628 43 643 122L719 524C735 610 741 615 822 622L828 650Z" id="g113-73"></path></g><g transform="matrix(.013,0,0,-0.013,41.532,0)"><path d="M95 130C70 130 46 113 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d="M513 0V26C455 31 447 37 447 103V278C447 398 390 449 309 449C255 449 202 412 166 376V712C127 700 67 684 19 677V653C85 647 87 643 87 580V103C87 37 79 31 19 26L18 0H231V26C171 32 166 39 166 103V341C194 373 232 392 270 392C337 392 368 351 368 269V103C368 38 360 32 302 26V0H513Z" id="g121-102"></path></g><g transform="matrix(.013,0,0,-0.013,64.141,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path></g></svg></td><td class="align_center"><svg height="10.9301pt" id="M19" style="vertical-align:-2.1637pt" version="1.1" viewbox="-0.0498162 -8.7664 19.1508 10.9301" width="19.1508pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M692 302H438V274C537 267 543 260 543 188V103C543 61 531 48 511 37C489 26 458 20 424 20C231 20 146 188 146 333C146 517 258 630 411 630C507 630 582 597 606 474L634 480C627 546 622 601 619 636C586 643 510 665 426 665C230 665 44 552 44 321C44 122 191 -15 411 -15C491 -15 573 7 635 21C629 49 628 81 628 116V202C628 261 632 266 692 274V302Z" id="g121-69"></path></g><g transform="matrix(.013,0,0,-0.013,9.295,0)"><path d="M720 -138C627 -96 538 -41 476 2C594 39 703 153 703 331C703 532 552 665 384 665C170 665 44 499 44 315C44 215 87 129 147 73C211 11 298 -11 355 -14C476 -99 554 -136 584 -144S664 -160 712 -159L720 -138ZM348 25C231 49 146 172 146 342C146 533 249 629 360 629C497 629 601 510 601 302C601 142 523 51 443 28C434 34 425 41 416 47L348 25Z" id="g121-79"></path></g></svg> <br/><svg height="13.8595pt" id="M20" style="vertical-align:-2.2681pt" version="1.1" viewbox="-0.0498162 -11.5914 51.4605 13.8595" width="51.4605pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M797 0V26C739 32 732 36 732 103V296C732 394 682 449 605 449C576 449 550 437 529 423C504 407 475 389 446 366C425 418 382 449 334 449C303 449 279 437 253 421C222 403 201 385 180 371V452C135 432 85 419 41 411V388C99 379 102 374 102 310V103C102 38 93 32 27 26V0H238V26C189 32 180 38 180 103V338C210 363 250 390 289 390C351 390 377 348 377 275V103C377 37 368 32 306 26V0H520V26C465 32 456 38 456 101V296C456 314 455 326 453 338C491 369 529 390 565 390C628 390 653 345 653 274V107C653 36 642 32 583 26V0H797Z" id="g121-107"></path></g><g transform="matrix(.0091,0,0,-0.0091,15.145,-5.741)"><path d="M290 377C321 398 342 415 358 430C378 450 389 473 389 502C389 578 329 635 238 635H237C184 635 137 610 109 578L64 515L88 493C112 529 154 573 208 573S303 542 303 482C303 409 233 370 141 341L149 308C165 313 190 319 215 319C272 319 341 283 341 193C342 98 292 43 222 43C163 43 122 72 96 94C88 101 79 100 70 94C61 87 47 73 46 60C44 47 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193 193C144 135 87 78 32 23V0H405C417 45 427 89 440 131L412 140Z" id="g113-51"></path></g><g transform="matrix(.013,0,0,-0.013,29.487,0)"><path d="M469 201V252H50V201H469Z" id="g190-178"></path></g><g transform="matrix(.013,0,0,-0.013,36.272,0)"><path d="M456 178V225H360V632H320C217 496 115 347 20 206V178H280V106C280 40 276 34 189 27V0H445V27C364 34 360 39 360 106V178H456ZM280 225H82C149 335 214 431 278 520H280V225Z" id="g113-53"></path></g></svg></td><td class="align_center">Rectangle</td><td class="align_center">Coal arenaceous shale interbed</td><td class="align_center">4.20 × 2.45</td><td class="align_center">0.6/0.7</td><td class="align_center">0.3</td><td class="align_center">YT2 air-jack leg drill</td></tr><tr><td class="align_left">Return entry</td><td class="align_center">Rock, <svg height="12.7178pt" id="M22" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 40.5724 12.7178" width="40.5724pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M619 670C619 686 593 712 555 712S459 686 410 634S335 504 320 430H250L219 400L222 388H312L258 73C223 -133 201 -166 187 -180C175 -191 158 -199 140 -199C123 -199 88 -188 74 -172C68 -166 63 -164 54 -171C38 -185 23 -201 23 -215C23 -236 60 -261 93 -261C122 -261 161 -247 207 -200C268 -138 300 -71 337 94C365 220 376 277 394 387L501 399L521 430H401C432 623 464 665 501 665C524 665 544 651 567 627C577 617 583 618 592 625C601 631 619 651 619 670Z" id="g113-103"></path></g><g transform="matrix(.013,0,0,-0.013,11.984,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z" id="g117-34"></path></g><g transform="matrix(.013,0,0,-0.013,23.247,0)"><path d="M153 550H386L412 615L406 623H120L82 318C104 327 142 338 184 338C294 338 347 275 347 187C347 112 305 39 221 39C160 39 119 71 97 89C88 97 80 96 71 90C59 80 50 67 49 57C48 45 52 36 66 23C80 9 123 -12 169 -12C221 -11 288 15 342 59C403 109 431 165 431 225C431 308 366 395 238 395C212 395 165 379 127 364L153 550Z" id="g113-54"></path></g><g transform="matrix(.013,0,0,-0.013,29.487,0)"><path d="M300 253H71L57 198H286L300 253Z" id="g190-46"></path></g><g transform="matrix(.013,0,0,-0.013,34.132,0)"><path d="M137 343C167 482 260 545 321 574C357 591 397 603 429 609L423 641C382 634 335 622 295 608C189 570 37 457 37 238C37 84 125 -12 242 -12C362 -12 447 89 447 209C447 311 374 393 267 393C247 393 226 386 204 376L137 343ZM227 337C318 337 361 256 361 173C361 105 336 22 258 22C176 22 126 120 126 240C126 266 127 291 132 310C155 323 189 337 227 337Z" id="g113-55"></path></g></svg></td><td class="align_center">Semicircular arch</td><td class="align_center">Siltstone sandy mudstone interbed</td><td class="align_center">5.75 × 1.50</td><td class="align_center">5/25</td><td class="align_center">0.5</td><td class="align_center">CMJ2-27 hydraulic jumbo</td></tr><tr class="table-tr"><td colspan="8"><hr class="tbody-hr"/></td></tr></table></td></tr><tr class="table-fn"><td><div><span class="nowrap"><svg height="11.439pt" id="M23" style="vertical-align:-2.15067pt" version="1.1" viewbox="-0.0498162 -9.28833 49.0716 11.439" width="49.0716pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M956 650H736V622C814 613 818 602 804 542C789 471 733 275 691 141H689C628 314 570 476 514 641H485C434 478 377 312 323 142H321C277 284 238 419 199 554C184 605 186 613 259 622V650H16V622C77 615 92 606 117 524C172 346 228 170 281 -11H312C363 151 419 312 475 488H477C528 343 597 150 652 -11H683C765 269 826 458 848 522C878 605 887 613 956 622V650Z" id="g121-85"></path></g><g transform="matrix(.013,0,0,-0.013,12.623,0)"><path d="M303 0V28C221 34 213 39 213 125V525C213 610 221 616 303 622V650H38V622C120 616 128 610 128 525V125C128 40 120 34 38 28V0H303Z" id="g121-71"></path></g><g transform="matrix(.013,0,0,-0.013,17.056,0)"><path d="M95 130C70 130 46 113 46 88C46 72 54 64 59 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id="g121-75"></path></g></svg>,</span> water inflow; normal/maximum water inflow; and <span class="nowrap"><svg height="10.9301pt" id="M24" style="vertical-align:-2.1637pt" version="1.1" viewbox="-0.0498162 -8.7664 19.1508 10.9301" width="19.1508pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M692 302H438V274C537 267 543 260 543 188V103C543 61 531 48 511 37C489 26 458 20 424 20C231 20 146 188 146 333C146 517 258 630 411 630C507 630 582 597 606 474L634 480C627 546 622 601 619 636C586 643 510 665 426 665C230 665 44 552 44 321C44 122 191 -15 411 -15C491 -15 573 7 635 21C629 49 628 81 628 116V202C628 261 632 266 692 274V302Z" id="g121-69"></path></g><g transform="matrix(.013,0,0,-0.013,9.295,0)"><path d="M720 -138C627 -96 538 -41 476 2C594 39 703 153 703 331C703 532 552 665 384 665C170 665 44 499 44 315C44 215 87 129 147 73C211 11 298 -11 355 -14C476 -99 554 -136 584 -144S664 -160 712 -159L720 -138ZM348 25C231 49 146 172 146 342C146 533 249 629 360 629C497 629 601 510 601 302C601 142 523 51 443 28C434 34 425 41 416 47L348 25Z" id="g121-79"></path></g></svg>,</span> absolute gas emission quantity.<br/></div></td></tr></table>

<div>Main parameters of the industrial test tunnels.</div>

Shock and Vibration

tab4

Table 4

Table 4: Application and Development of an Environmentally Friendly Blast Hole Plug for Underground Coal Mines 