CN101845962A - Method and device for reducing dust in air return channel of coal mining working surface - Google Patents

Method and device for reducing dust in air return channel of coal mining working surface Download PDF

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Publication number
CN101845962A
CN101845962A CN201010196482A CN201010196482A CN101845962A CN 101845962 A CN101845962 A CN 101845962A CN 201010196482 A CN201010196482 A CN 201010196482A CN 201010196482 A CN201010196482 A CN 201010196482A CN 101845962 A CN101845962 A CN 101845962A
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dust
water
cascade
channel
air
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CN101845962B (en
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张国军
徐继民
董永慧
吴在兵
李巍栋
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Beijing Tiandi Huatai Mining Management Co Ltd
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Beijing Tiandi Huatai Mining Engineering & Technology Co Ltd
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Abstract

The invention relates to a method and a device for reducing dust in an air return channel of a coal mining working surface. The device comprises a channel in which air flows in one direction; a water supply pipe in which pressure water flows is arranged on a top board of the channel along the width direction of the channel; at least one water orifice is uniformly distributed in the leeward direction of the water supply pipe; a dust-absorbing water curtain is arranged a certain distance away from a downwind direction of the water orifice and is hung on the top board of the channel; and the width and the height of the dust-absorbing water curtain are the same as those of the cross section of the channel. Water is sprayed on the dust-absorbing water curtain and a thin water film is formed on the mesh of the dust-absorbing water curtain so as to adsorb the dust in the flowing air. The method achieves higher dust absorbing efficiency than a method of directly spraying water in the flowing air. Since the size of the dust-absorbing water curtain is the same as that of the cross section of the channel, the dust in the air flowing through the entire cross section of the channel on which the dust-absorbing water curtain is hung is reduced, namely, the entire cross section of the entire channel is blocked by a water curtain. Therefore, a dust reducing effect is very remarkable.

Description

A kind of reducing dust in air return channel of coal mining working surface method and apparatus
Technical field
The present invention relates to a kind of reducing dust in air return channel of coal mining working surface method and apparatus, is a kind of method and apparatus that is used for the mine dedusting.
Background technology
In coal mine, coal-winning machine can produce a large amount of dust when fully mechanized coal face carries out coal mining activity, not only pollute working environment, and the harm very big, and when airborne dust content reaches finite concentration, just have the danger of blast staff's healthy generation.Though external spraying or other measurements for reduction in coal-winning machine is provided with, still have a lot of dust especially fine solid particle come out with the drift of flowing of the air in the tunnel, these dust are easy to be sucked lung by human body and impair one's health.
In order to eliminate the great harm that Mine Dust coal supply mine belt comes, the measure of a little depositing dust waterings has all been adopted in each colliery, each ore deposit is except carrying out also will being no less than the water curtain of twice in the setting of coal-face air-return duct the necessary atomizing de-dusting to relevant place according to the rules regulation now.It is the Sprayable formation water curtain of a pipe multiple spot (welding a plurality of shower nozzles on a water pipe) that water curtain is all adopted in most of collieries, this is utilized a single pipe multipoint mode water curtain depositing dust mode to be difficult to the tunnel is formed full section covering, reason is shorter at the coverage of shower nozzle spraying, the water smoke of ejection is condensed into bigger water droplet rapidly, and the space between the water droplet is bigger, can not effectively adsorb the dust in the control.Even if the increasing injection flow rate also can't increase effective dust removing effects.Because it is limited that distance is penetrated in spraying, only spraying can not effectively connect the top, tunnel sternly fully, thereby can not reach desirable dust-laying effect.
Summary of the invention
For solving the prior art problem, the present invention proposes a kind of reducing dust in air return channel of coal mining working surface method and apparatus.The method of the invention hangs the way of dust suction cascade at the mine working face air return way.Shower nozzle water smoke is injected directly on the top of dust suction cascade, current have formed one very thin moisture film from top to bottom on the mesh of dust suction cascade, dust is with distinguished and admirable when flowing to the dust suction cascade, will be attached on the moisture film, dust can drop near the dust suction cascade after passing through the moisture film humidification rapidly, thereby has reached the effect of depositing dust.
The object of the present invention is achieved like this: a kind of reducing dust in air return channel of coal mining working surface device, comprise: have folk prescription to the mobile tunnel of air, the top board in described tunnel is equipped with the feed pipe that is connected with press water along the span length direction, a water jet is lacked in being evenly distributed on the wind direction of described feed pipe, leeward one segment distance at described water jet is provided with the dust suction cascade, described dust suction cascade is hung on the top board in tunnel, described dust suction cascade wide and high and cross section, tunnel wide and high identical.
Use a kind of reducing dust in air return channel of coal mining working surface method of said apparatus, the step of described method is as follows:
The step of water spray: be used for water is sprayed at depositing dust cascade top uniformly;
The equally distributed step of water: the water that is used to be sprayed on depositing dust cascade top flows downward uniformly and formed very thin moisture film one on mesh;
The step that dust is adsorbed: when the air that is used to have dust flow through the mesh of depositing dust cascade, dust was attracted on the moisture film of mesh;
The step that dust falls: be used for being adsorbed on the water dust,, realize reducing the dust in the moving air under water with falling.
The beneficial effect that the present invention produces is: utilization of the present invention is sprayed at water on the dust suction cascade, makes on the mesh of dust suction cascade and forms very thin moisture film, and the dust in the moving air is adsorbed.This mode than directly in flow air the efficient of the mode dust suction of spray water higher.Because the size of dust suction cascade is identical with the cross section in tunnel, the air that hangs with whole cross section, dust suction cascade tunnel will be flow through and depositing dust can both be obtained, be about to the full section water curtain of whole tunnel and block, dust-laying effect is very remarkable.
Description of drawings
The invention will be further described below in conjunction with drawings and Examples.
Fig. 1 is the schematic diagram of the embodiment of the invention one described device for reducing dust;
Fig. 2 is the schematic diagram of application example device for reducing dust in the embodiment of the invention one, is as B direction view among Fig. 1;
Fig. 3 is the dust suction cascade schematic diagram that is made of braid of the embodiment of the invention two described device for reducing dust;
Fig. 4 is the dust suction cascade schematic diagram that is made of sheeting of the embodiment of the invention two described device for reducing dust.
The specific embodiment
Embodiment one:
Present embodiment is a kind of reducing dust in air return channel of coal mining working surface device, as shown in Figure 1.Present embodiment comprises: have folk prescription to the mobile tunnel 1 of air, the top board in described tunnel is equipped with the feed pipe 2 that is connected with press water along the span length direction, a water jet 3 is lacked in being evenly distributed on the wind direction of described feed pipe, leeward one segment distance at described water jet is provided with dust suction cascade 4, described dust suction cascade is hung on the top board in tunnel, described dust suction cascade wide and high and cross section, tunnel wide and high identical.
The described device for reducing dust of present embodiment is to have increased the dust suction cascade on the basis of traditional device for reducing dust.All there is suitable air to flow in the tunnel, and requires according to a certain direction to flow, as the indicated direction of arrow A among Fig. 1.Flow air is to keep the pure and fresh of air in the tunnel in order to make, and can take away the dust that produces in the coal mining.Traditional device for reducing dust only is a water spray, utilizes the water smoke that forms, and absorbs dust in the air.This mode is difficult on the interface of whole tunnel and forms complete and effective, and water smoke uniformly.Water smoke can be condensed into bigger water droplet in the decline process, the space between the water droplet increases, and the effect that absorbs dust is reduced greatly.Certainly increase injection flow rate, can increase other problem again, therefore, increase injection flow rate and inadvisable but increase injection flow rate.Present embodiment is provided with a dust suction cascade by the leeward at the water jet of atomized water spray, sees Fig. 1.Evenly be covered with the mesh that penetrates on this dust suction cascade.When water is sprayed on the dust suction cascade, on mesh, form very thin moisture film, and in mesh, form the bigger microenvironment of humidity, make the entrained dust of the air that flows through mesh by the water vapor absorption in the mesh microenvironment.The dust suction cascade can be made by flexible material, purpose be when personnel or vehicle by the time can lift easily, for example mine car by the time, what the dust suction cascade will nature is boosted by mine car, when mine car is left away, falls automatically, need not people's management.The height and width in the height and width of dust suction cascade and cross section, tunnel are suitable.This is for whole tunnel being completed into the water smoke curtain on an interface, improving the efficient of depositing dust.But in real work, can not fit together perfectly, some slits are always arranged.For make depositing dust have effect to reduce these slits as far as possible.Since the dust suction cascade is a kind of curtain, all can have various forms.The dust suction cascade can be that the neck line is a hard material, steel bar etc. for example, and parallel is flexible, is similar to bamboo screen.In the time of above water is sprayed on, between each parallel, form the bigger microenvironment of water smoke, equally effectively dedusting.The dust suction cascade can also be that graticule is arranged all is that flexible material is made, and for example, the nylon rope grid type of working out is similar to screen window, and water is sprayed on can form the bigger microenvironment of water smoke equally in the grid.The dust suction cascade can also be the curtain of rubber, on be covered with mesh.
The application example of present embodiment: one high be 3 meters, wide is in 4.5 the tunnel dust suction cascade to be set, feed pipe adopts the 12.5mm iron pipe, according to span length, shower nozzle of every 450mm welding (welding in the same way side by side) is installed 9 shower nozzles altogether, it is 0.2MP that pressure of supply water is not less than each shower nozzle water spray pressure of 0.3MP * 9=2.7MP(, now pressing 0.3MP calculates), hang the dust suction cascade at the downwind side 600mm place of distance shower nozzle, as shown in Figure 2.The dust suction cascade will guarantee that full section covers.The material of dust suction cascade is an anti-flammability colloid lace curtaining, and mesh is 6 * 6mm.Spray to dust suction cascade and back junction during spraying, jet angle is by 45 ° of calculating, the width that each shower nozzle is injected on the dust suction cascade is about 650mm, according to sprinkler spacing is 450mm, can guarantee sprays when being sprayed on the netted curtain, and respectively there is the setting-out line of 100mm on both sides, and then realized that the full section water curtain in tunnel blocks, effective depositing dust.After the dust suction cascade of above-mentioned example was installed, dust-laying effect was fairly obvious, and the breathing of underground operators has obtained very big improvement, and the flue coal dust in the air return way return has obtained handling timely and effectively, and mine dust has obtained the control of essence.According to following measured data as can be known:
1, hang water curtain curtain dust concentration (getting the numerical value in producing for 3 times) before:
(1) detection site: 502 air return way;
Detection time: on August 10th, 2009
Total dust concentration: 8.2mg/m 3(transfiniting 0.2)
Exhale dust concentration: 5.0mg/m 3(having reached the value of defining)
(2) detection site: 502 air return way;
Detection time: on August 25th, 2009
Total dust concentration: 8.0mg/m 3(having reached the value of defining)
Exhale dust concentration: 4.9mg/m 3(near the value of defining)
(3) detection site: 502 air return way;
Detection time: on September 10th, 2009
Total dust concentration: 7.8mg/m 3(qualified substantially)
Exhale dust concentration: 4.8mg/m 3(qualified substantially)
2, hang water curtain curtain dust concentration (getting the numerical value in producing for 3 times) afterwards:
(1) detection site: 502 air return way;
Detection time: on October 11st, 2009
Total dust concentration: 7.0mg/m 3(qualified)
Exhale dust concentration: 4.2mg/m 3(qualified)
(2) detection site: 502 air return way;
Detection time: on November 10th, 2009
Total dust concentration: 7.2mg/m 3(qualified)
Exhale dust concentration: 4.6mg/m 3(qualified)
(3) detection site: 502 air return way;
Detection time: on November 25th, 2010
Total dust concentration: 7.2mg/m 3(qualified)
Exhale dust concentration: 4.5mg/m 3(qualified)
From above-mentioned data as can be seen: total dust concentration descends 10.8%; Exhale dust concentration to descend: 9.5%, effect is fairly obvious.
Embodiment two:
Present embodiment is the improvement of embodiment one, is the refinement of the described device for reducing dust of embodiment about dust suction cascade material, shown in Fig. 3,4.The described dust suction cascade of present embodiment is made up of thin flexible material, and mesh evenly gathers on the flexible material surface.
The described dust suction cascade of present embodiment is made up of thin flexible material, and thin flexible material can be the flaky material of north material, rubber, north glue, and thickness does not wait to 40 millimeters at 5 millimeters.Thin material damages easily, but lifts merrilyyer and lightheartedly, is suitable for the walkway.Thicker material is because the length of through hole is longer, and the water smoke of formation is better, and not fragile, but lifts heavylier, is suitable for the tunnel that vehicle passes through.
The described through hole of present embodiment, can be the through hole that braid interval between the graticule in the braiding process forms, as shown in Figure 2, also can be the flaky material formation of evenly punching, (through hole of expression is the expression of exaggeration among Fig. 2,3, and the actual conditions through hole is much smaller) as shown in Figure 3.
Embodiment three:
Present embodiment is the improvement of embodiment two, is the refinement of embodiment two about flexible material.The described thin flexible material of present embodiment is an anti-flammability colloid lace curtaining.
Embodiment four:
Present embodiment is to use a kind of reducing dust in air return channel of coal mining working surface method of the described device of the foregoing description.The step of the described method of present embodiment is as follows:
1) Pen Shui step: be used for water is sprayed at depositing dust cascade top uniformly.Clean water is sprayed at the top of dust suction cascade.The top that why water is sprayed on the dust suction cascade is owing to be convenient to arrange sparge pipe and water jet.Certainly arrange sparge pipe and water jet in the both sides in tunnel, but like that the spray of position intermediate water be sprayed on the top of dust suction cascade less than, water can gravity, water is dirty naturally.
2) the equally distributed step of water: the water that is used to be sprayed on depositing dust cascade top flows downward uniformly and formed very thin moisture film one on mesh.Accumulate in during water flows downward on the mesh, form the water surface, and in mesh, form the bigger microenvironment of humidity.
3) step that is adsorbed of dust: when the air that is used to have dust flow through the mesh of depositing dust cascade, dust was attracted on the moisture film of mesh.When the air that has a dust flow through mesh, the water smoke in the microenvironment in the mesh is very easy to be accumulated on the airborne dust, formed bigger water droplet and fell, and the formation of this and rain is similar, is thinking on the macroscopic view that dust is adsorbed on the moisture film.
4) step of dust whereabouts: be used for being adsorbed on the water dust,, realize reducing the dust in the moving air under water with falling.Because water constantly sprays from water jet, water flowing from top to bottom constantly arranged, play the effect of washing away the dust suction cascade, after the water in the mesh has absorbed dust, just swept away the dust suction cascade like this by the current of back, flow to the dust suction cascade below.The following dust collection that can be special of dust suction cascade is implemented.But under normal conditions, the ground in tunnel is very coarse, and other flowing water is arranged, and can in linely have the flowing water of dust.
Said process is the fragment of a successive process, and this fragment is continuously moved, and forms whole process.
It should be noted that at last, below only unrestricted in order to technical scheme of the present invention to be described, although the present invention is had been described in detail with reference to the preferred arrangement scheme, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention (such as arrangement of the material of dust suction cascade, profile, size, water pipe spout etc.), and not break away from the spirit and scope of technical solution of the present invention.

Claims (4)

1. reducing dust in air return channel of coal mining working surface device, comprise: have folk prescription to the mobile tunnel of air, the top board in described tunnel is equipped with the feed pipe that is connected with press water along the span length direction, a water jet is lacked in being evenly distributed on the wind direction of described feed pipe, it is characterized in that, leeward one segment distance at described water jet is provided with the dust suction cascade, described dust suction cascade is hung on the top board in tunnel, described dust suction cascade wide and high and cross section, tunnel wide and high identical.
2. device for reducing dust according to claim 1 is characterized in that, described dust suction cascade is made up of thin flexible material, and mesh evenly gathers on the flexible material surface.
3. device for reducing dust according to claim 2 is characterized in that, described thin flexible material is an anti-flammability colloid lace curtaining.
4. use a kind of reducing dust in air return channel of coal mining working surface method of the described device of claim 1, it is characterized in that the step of described method is as follows:
The step of water spray: be used for water is sprayed at depositing dust cascade top uniformly;
The equally distributed step of water: the water that is used to be sprayed on depositing dust cascade top flows downward uniformly and formed very thin moisture film one on mesh;
The step that dust is adsorbed: when the air that is used to have dust flow through the mesh of depositing dust cascade, dust was attracted on the moisture film of mesh;
The step that dust falls: be used for being adsorbed on the water dust,, realize reducing the dust in the moving air under water with falling.
CN 201010196482 2010-06-10 2010-06-10 Method and device for reducing dust in air return channel of coal mining working surface Active CN101845962B (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102182458A (en) * 2011-04-14 2011-09-14 淮北矿业股份有限公司 Induced draft water curtain dust removing device for intercepted coal mining machine
CN102562129A (en) * 2012-02-21 2012-07-11 中南大学 Dust removal device for intake air of mine
CN104500142A (en) * 2014-12-23 2015-04-08 常熟市矿山机电器材有限公司 Underground coal mine dust measuring device
CN109209467A (en) * 2018-07-18 2019-01-15 山东大学 A kind of full-automatic curtain dust-extraction unit in suspension type tunnel
CN111502736A (en) * 2020-04-24 2020-08-07 中煤科工集团重庆研究院有限公司 Dust source automatic isolation spraying dust control method and device

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RU2005138457A (en) * 2005-12-09 2007-06-20 Виктор Иванович Попов (RU) WATER BLOCK
CN201246178Y (en) * 2008-08-05 2009-05-27 滕广林 Mine deep well wind lack filtering device
CN101672194A (en) * 2009-10-08 2010-03-17 山东华宁矿业集团有限公司 Gauze dustproof filtering device
CN201439718U (en) * 2009-07-23 2010-04-21 上海大屯能源股份有限公司 Double dustproof water curtain for cutting coal on coal mining work surface
CN201714419U (en) * 2010-06-10 2011-01-19 北京天地华泰采矿工程技术有限公司 Dust removing device for coal mine excavation working face return airway

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Publication number Priority date Publication date Assignee Title
DE2912326A1 (en) * 1979-03-28 1980-10-02 Nalco Chemie Gmbh Deutsche Polyelectrolyte addn. for wet dust control - e.g. in mining, pref. using opt. modified acrylamide! polymer or poly:amine
RU2005138457A (en) * 2005-12-09 2007-06-20 Виктор Иванович Попов (RU) WATER BLOCK
CN201246178Y (en) * 2008-08-05 2009-05-27 滕广林 Mine deep well wind lack filtering device
CN201439718U (en) * 2009-07-23 2010-04-21 上海大屯能源股份有限公司 Double dustproof water curtain for cutting coal on coal mining work surface
CN101672194A (en) * 2009-10-08 2010-03-17 山东华宁矿业集团有限公司 Gauze dustproof filtering device
CN201714419U (en) * 2010-06-10 2011-01-19 北京天地华泰采矿工程技术有限公司 Dust removing device for coal mine excavation working face return airway

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102182458A (en) * 2011-04-14 2011-09-14 淮北矿业股份有限公司 Induced draft water curtain dust removing device for intercepted coal mining machine
CN102562129A (en) * 2012-02-21 2012-07-11 中南大学 Dust removal device for intake air of mine
CN102562129B (en) * 2012-02-21 2014-12-10 中南大学 Dust removal device for intake air of mine
CN104500142A (en) * 2014-12-23 2015-04-08 常熟市矿山机电器材有限公司 Underground coal mine dust measuring device
CN109209467A (en) * 2018-07-18 2019-01-15 山东大学 A kind of full-automatic curtain dust-extraction unit in suspension type tunnel
CN111502736A (en) * 2020-04-24 2020-08-07 中煤科工集团重庆研究院有限公司 Dust source automatic isolation spraying dust control method and device

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Address after: 100013 Beijing city Chaoyang District Hepingli 13 No. 35 coal Street building room 1607

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Patentee before: Beijing Tiandi Huatai Mining Engineering & Technology Co., Ltd.