CN109236343B - Pressure-suction switching positive-pressure ventilation method for tunneling head - Google Patents
Pressure-suction switching positive-pressure ventilation method for tunneling head Download PDFInfo
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- CN109236343B CN109236343B CN201811121373.9A CN201811121373A CN109236343B CN 109236343 B CN109236343 B CN 109236343B CN 201811121373 A CN201811121373 A CN 201811121373A CN 109236343 B CN109236343 B CN 109236343B
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- 238000009423 ventilation Methods 0.000 title claims abstract description 39
- 230000005641 tunneling Effects 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000005086 pumping Methods 0.000 abstract description 5
- 238000011144 upstream manufacturing Methods 0.000 abstract description 2
- 238000005422 blasting Methods 0.000 description 11
- 239000000779 smoke Substances 0.000 description 11
- 238000007599 discharging Methods 0.000 description 6
- 238000000605 extraction Methods 0.000 description 2
- 239000003517 fume Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
- E21F1/006—Ventilation at the working face of galleries or tunnels
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
- E21F1/04—Air ducts
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
- Ventilation (AREA)
Abstract
A pressure-suction switching positive pressure ventilation method for a tunneling head is characterized in that 1 local fan and a three-way switching valve are respectively arranged on the upstream side of fresh air flow and near the tunnel face, and the local fan is connected with the three-way switching valve and the three-way switching valve through an air duct. Through the automatic switching function of the three-way switching valve, the local fan at the position of the fresh air flow is started to realize press-in ventilation and send the fresh air flow to the tunneling surface from the fresh air flow upwind side, and the local fan near the tunneling surface is started to realize draw-out ventilation and discharge dirty air of the tunneling surface to the fresh air flow downwind side. The invention can solve the problem of circulation of pressure-pumping and switching polluted air in the prior art, improve the tunneling ventilation quality and reduce the tunneling ventilation cost.
Description
Technical Field
The invention relates to the field of underground engineering ventilation, in particular to a tunneling ventilation method for underground engineering.
Background
Tunneling ventilation is required in the tunneling construction process of underground engineering such as tunnels, mine roadways and the like, and the conventional modes at present are press-in type, draw-out type and mixed type. The forced ventilation local fan (local ventilator) is placed on the fresh air flow upwind side, the flexible wind cylinder supplies air to the tunneling tunnel face, dirty air is discharged from the tunnel or the roadway, and the air pressure in the wind cylinder is higher than the air pressure in the tunnel or the roadway and is positive pressure ventilation. The drawing-out type ventilation local fan is placed on the leeward side of fresh air flow, the ventilation rigid air cylinder sucks out dirty air from the tunneling tunnel face, the fresh air flow flows in from the tunnel or the roadway, and the air pressure in the air cylinder is lower than the air pressure in the tunnel or the roadway and is negative pressure ventilation. The above-mentioned push-in type and pull-out type are arranged simultaneously in a mixed mode, and are not commonly adopted due to the large number of equipment, large investment and high operating electricity charge.
The forced ventilation tunneling face air flow is high in quality, the extraction type ventilation blasting smoke discharging time is short, the advantages of two ventilation modes can be integrated if the forced ventilation blasting smoke discharging time is switched, the tunneling ventilation air quality is improved, and the blasting smoke discharging time is shortened. The pressure-suction switching is realized by normally and reversely rotating a rigid air duct and an axial flow type local fan in the industry at present, and the following problems exist: 1. the reverse air volume of the axial flow type local fan is about 60 percent of the forward air volume, and the reverse ventilation efficiency is low; 2. the axial flow type local fan is always provided with circulating dirty air in one of two ventilation modes of pressure pumping and suction no matter the axial flow type local fan is placed on the upwind side or the downwind side of fresh air flow; 3. the rigid air duct is heavy in weight and inconvenient to install, and the manufacturing cost is about 3 times of that of the flexible air duct.
CN204113709U discloses a hybrid office fan, which has the solution: the office fan maintains positive rotation, and the problems of low efficiency of office fan reverse rotation can be solved by arranging a reverse air duct, a plurality of groups of three-way air ducts and valves between an air inlet and an air outlet of the office fan and realizing pressure-suction switching by regulating and controlling the valves to switch the rigid air duct to be in wind power connection with the air inlet or the air outlet of the office fan, but the problems of high manufacturing cost, inconvenience in installation and the like of circulating dirty air and the rigid air duct cannot be solved.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the pressure-suction switching ventilation method for the heading head overcomes the defects in the prior art, and not only can solve the problem of pressure-suction switching circulating dirty air, but also can improve the heading ventilation quality and reduce the heading ventilation cost.
The technical scheme adopted by the invention for solving the technical problems is as follows: a pressure-suction switching positive-pressure ventilation method for a heading head comprises the following steps: the air outlet of the 1# local fan is connected with the normally closed port of the 1# three-way switching valve through an air duct I, the air outlet of the 2# local fan is connected with the normally closed port of the 2# three-way switching valve through an air duct II, the main air port of the 1# three-way switching valve is connected with the main air port of the 2# three-way switching valve through an air duct III, the normally open port of the 1# three-way switching valve is connected with an air duct IV and extends to the fresh air flow down-wind side, and the normally open port of the 2# three-way switching valve is connected with an air duct V and extends to the tunnel face;
when the air is forced to ventilate, the 2# local fan is closed, the 1# local fan is opened, the normally closed opening of the 1# three-way switching valve is automatically switched to be communicated with the main air inlet under the action of the air pressure of the 1# local fan, the normally open opening of the 2# three-way switching valve is communicated with the main air inlet, and fresh air flows through the 1# local fan, the air duct I, the 1# three-way switching valve, the air duct III, the 2# three-way switching valve, the normally open opening of the 2# three-way switching valve and the air duct V to reach the;
when the air is ventilated in a drawing mode, the 1# local fan is closed, the 2# local fan is opened, the 2# three-way switching valve automatically switches the normally closed port to be communicated with the main air port under the action of the air pressure of the 2# local fan, the normally open port of the 1# three-way switching valve is communicated with the main air port, and the palm face dirty air reaches the fresh air flow downdraft side through the 2# local fan, the air duct II, the 2# three-way switching valve, the air duct III, the 1# three-way switching valve, the normally open port of the 1# three-way switching valve and the air duct.
Further, a valve plate and an elastic component are arranged in the No. 1 three-way switching valve, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed opening is under the action of the wind pressure of the No. 1 local fan, the wind pressure overcomes the acting force of the elastic component to turn the valve plate to the normally open opening, the normally open opening is closed, and the normally closed opening is communicated with the main air inlet.
Further, a valve plate and an elastic component are arranged in the No. 2 three-way switching valve, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed port is under the action of the wind pressure of the No. 2 local fan, the wind pressure overcomes the acting force of the elastic assembly to turn the valve plate to the normally open port, the normally open port is closed, and the normally closed port is communicated with the main air port.
Furthermore, the air duct I, the air duct II, the air duct III, the air duct IV and the air duct V can adopt flexible air ducts or rigid air ducts.
Furthermore, the air inlet of the 2# local fan near the tunnel face can be connected with a telescopic rigid air duct, so that the workload of moving the 2# local fan near the tunnel face along with tunneling is reduced.
Furthermore, a wind speed and direction sensor I is arranged in the No. 1 three-way switching valve, and the No. 1 local fan is electrically locked through the wind speed and direction sensor I; be equipped with wind speed and direction sensor II in the 2# three-way switch valve, the 2# office fan passes through wind speed and direction sensor II and realizes electric shutting, can only open a office fan simultaneously.
The invention has the beneficial effects that: the flexible wind tube can be used for supplying air, the problem of dirty air circulation of pressure pumping switching in the prior art can be solved, the tunneling ventilation quality can be improved, and the tunneling ventilation cost can be reduced.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 illustrates the press-in venting condition of the present invention;
FIG. 3 is a draw out ventilation condition of the present invention;
in the figure: the air flow control device comprises a 1-1# local fan, a 2-2# local fan, a 3-1# three-way switching valve, a 4-2# three-way switching valve, a 5-air duct III, a 6-air duct V, a 7-air duct IV, an 8-telescopic rigid air duct, a 9-fresh air flow downdraft side, a 10-fresh air flow updraft side, a 11-palm surface, a 12-valve plate and elastic component, a 13-air speed and direction sensor I, a 14-fresh air flow direction and a 15-dirty air flow direction.
Detailed Description
The present invention is further illustrated by the following examples.
Examples
Referring to fig. 1, a method for pressure-suction switching positive pressure ventilation of a heading head comprises the following steps: a1 # local fan 1 and a 1# three-way switching valve 3 are arranged on the fresh air flow upstream side 10, a 2# local fan 2 and a 2# three-way switching valve 4 are arranged near a tunnel face 11, the 1# three-way switching valve 3 is divided into 3 air flow inlets and outlets, namely a normally open port, a normally closed port and a main air port, the 2# three-way switching valve 2 is divided into 3 air flow inlets and outlets, namely a normally open port, a normally closed port and a main air port, the air outlet of the No. 1 local fan 1 is connected with the normally closed port of the No. 1 three-way switching valve 3 through an air duct I, the air outlet of the No. 2 local fan 2 is connected with the normally closed port of the No. 2 three-way switching valve 4 through an air duct II, the main air port of the No. 1 three-way switching valve 3 is connected with the main air port of the No. 2 three-way switching valve 4 through an air duct III 5, a normally open port of the No. 1 three-way switching valve 3 is connected with an air duct IV 7 and extends to a fresh air flow downdraft side 9, and a normally open port of the No. 2 three-way switching valve 4 is connected with an air duct V6 and extends to a tunnel face 11;
when the air is forced to ventilate, the 2# local fan 2 is closed, the 1# local fan 1 is opened, the 1# three-way switching valve 3 is automatically switched to be communicated with the main air inlet under the action of the air pressure of the 1# local fan 1, the normally closed opening of the 2# three-way switching valve 4 is communicated with the main air inlet, and fresh air flows to the tunnel face 11 through the 1# local fan 1, the air duct I, the 1# three-way switching valve 3, the air duct III 5, the 2# three-way switching valve 4, the normally open opening of the 2# three-way switching valve 4 and the air duct V6, as shown in fig. 2;
when the air is ventilated in the drawing-out mode, the 1# office fan 1 is closed, the 2# office fan 2 is opened, the 2# three-way switching valve 4 is automatically switched to be normally closed to be communicated with the main air inlet under the action of the air pressure of the 2# office fan 2, the normal opening of the 1# three-way switching valve 3 is communicated with the main air inlet, and the dirty air (dirty air flow direction 15) on the palm surface 11 reaches the fresh air flow downdraft side 9 through the 2# office fan 2, the air duct II, the 2# three-way switching valve 4, the air duct III 5, the 1# three-way switching valve 3, the normal opening of the 1# three-way switching valve 3 and the air duct IV 7.
A valve plate and an elastic component 12 are arranged in the No. 1 three-way switching valve 3, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed opening is under the action of the wind pressure of the No. 1 local fan, the wind pressure overcomes the acting force of the elastic component to turn the valve plate to the normally open opening, the normally open opening is closed, and the normally closed opening is communicated with the main air inlet.
A valve plate and an elastic component 12 are arranged in the No. 2 three-way switching valve 4, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed port is under the action of the wind pressure of the No. 2 local fan, the wind pressure overcomes the acting force of the elastic assembly to turn the valve plate to the normally open port, the normally open port is closed, and the normally closed port is communicated with the main air port.
The air duct I, the air duct II, the air duct III 5, the air duct IV 7 and the air duct V6 adopt flexible air ducts, and certainly, rigid air ducts can also be adopted.
And an air inlet of the 2# local fan 2 near the tunnel face 11 is connected with a telescopic rigid air duct 8, so that the workload of moving the 2# local fan near the tunnel face along with tunneling is reduced.
A wind speed and direction sensor I13 is arranged in the No. 1 three-way switching valve 3, the No. 1 local fan 1 is electrically locked through the wind speed and direction sensor I13, namely the wind speed and direction sensor I13 in the No. 1 three-way switching valve 3 monitors that the wind speed and direction signal lock 1 local fan 1 cannot be started; and a wind speed and direction sensor II is arranged in the 2# three-way switching valve 4, the 2# local fan 2 realizes electric locking through the wind speed and direction sensor II, namely the wind speed and direction sensor II in the 2# three-way switching valve 4 monitors that the 2# local fan 2 can not be started by locking a wind speed and direction signal.
The longest driving distance of a certain mine driving working face is 3200m, and the cross section area of the working face is 14.2m2The air quantity required by the palm surface is 5m3S, air supply rate of 7.4m3And/s, the diameter of the air duct is 1000mm, the local fan adopts an FBD 6.32 × 30kW counter-rotating axial flow local fan, and the ventilation mode is compared as follows.
The first scheme is as follows: the conventional flexible wind tube is selected for positive pressure forced ventilation, the equipment investment is 16.9 ten thousand yuan (2.5 ten thousand yuan for 1 local fan and 14.4 ten thousand yuan for 3200m flexible wind tube), the smoke exhaust and blasting wind speed is (5 + 7.4)/2/(14.2-3.14 0.5) =0.46m/s, and the maximum ventilation and blasting smoke time is 3200/0.46/60=116 min. The scheme has small investment, but the time for discharging the blasting smoke reaches 2 hours, so that the tunneling operation process is influenced.
Scheme II: the conventional rigid air duct is selected to realize the switching of pressure pumping ventilation through the positive and negative rotation of an axial flow local fan, the pressure pumping ventilation is usually carried out, the extraction ventilation is carried out when blasting smoke is exhausted, the equipment investment is 44.1 ten thousand yuan (2.5 ten thousand yuan for 1 local fan and 41.6 ten thousand yuan for 3200m rigid air duct), the air speed of the blasting smoke is (5 + 7.4) = 0.6/2/(3.14) = 0.5) =4.7m/s, and the maximum time for ventilating and blasting smoke exhausting is 3200/4.7/60=11 min. The scheme has large investment and short smoke discharging time, but has the problem of dirty air circulation.
The third scheme is as follows: by adopting the method, the equipment investment is 19.46 ten thousand yuan (5 ten thousand yuan for 2 local fans, 14.4 ten thousand yuan for 3200m flexible wind cylinders, 0.06 ten thousand yuan for 2 self-made three-way switching valves), the fume exhaust and blasting wind speed is (5 + 7.4)/2/(3.14 x 0.5) =7.9m/s, and the maximum time for ventilating and blasting fume exhaust is 3200/7.9/60=6.8 min. The invention has the advantages of small investment and short smoke discharging time, and can solve the problem of dirty air circulation and improve the quality of air flow.
Claims (3)
1. A positive pressure ventilation method for pressure-suction switching of a tunneling head is characterized by comprising the following steps: the air outlet of the 1# local fan is connected with the normally closed port of the 1# three-way switching valve through an air duct I, the air outlet of the 2# local fan is connected with the normally closed port of the 2# three-way switching valve through an air duct II, the main air port of the 1# three-way switching valve is connected with the main air port of the 2# three-way switching valve through an air duct III, the normally open port of the 1# three-way switching valve is connected with an air duct IV and extends to the fresh air flow down-wind side, and the normally open port of the 2# three-way switching valve is connected with an air duct V and extends to the tunnel face;
when the air is forced to ventilate, the 2# local fan is closed, the 1# local fan is opened, the normally closed opening of the 1# three-way switching valve is automatically switched to be communicated with the main air inlet under the action of the air pressure of the 1# local fan, the normally open opening of the 2# three-way switching valve is communicated with the main air inlet, and fresh air flows through the 1# local fan, the air duct I, the 1# three-way switching valve, the air duct III, the 2# three-way switching valve, the normally open opening of the 2# three-way switching valve and the air duct V to reach the;
when the air is ventilated in a drawing mode, the 1# office fan is closed, the 2# office fan is opened, the 2# three-way switching valve automatically switches a normally closed port to be communicated with the main air inlet under the action of the air pressure of the 2# office fan, a normally open port of the 1# three-way switching valve is communicated with the main air inlet, and the palm face dirty air reaches the leeward side of fresh air flow through the 2# office fan, the air duct II, the 2# three-way switching valve, the air duct III, the 1# three-way switching valve, the normally open port of the 1# three-way switching valve and the air;
the air duct I, the air duct II, the air duct III, the air duct IV and the air duct V adopt flexible air ducts;
a valve plate and an elastic component are arranged in the No. 1 three-way switching valve, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed port is under the action of the wind pressure of the No. 1 local fan, the wind pressure overcomes the acting force of the elastic assembly to turn the valve plate to the normally open port, the normally open port is closed, and the normally closed port is communicated with the main air port;
a valve plate and an elastic component are arranged in the No. 2 three-way switching valve, when the normally closed port has no wind pressure, the valve plate seals the normally closed port under the action of the elastic component, and the normally open port is communicated with the main air port; when the normally closed port is under the action of the wind pressure of the No. 2 local fan, the wind pressure overcomes the acting force of the elastic assembly to turn the valve plate to the normally open port, the normally open port is closed, and the normally closed port is communicated with the main air port.
2. A heading head pressure suction switching positive pressure ventilation method according to claim 1, characterized in that: and the 2# local fan air inlet near the tunnel face is connected with a telescopic rigid air duct.
3. A heading head pressure suction switching positive pressure ventilation method according to claim 1 or 2, characterized in that: a wind speed and direction sensor I is arranged in the No. 1 three-way switching valve, and the No. 1 local fan is electrically locked through the wind speed and direction sensor I; be equipped with wind speed and direction sensor II in the 2# three-way switch valve, the 2# office fan passes through wind speed and direction sensor II and realizes electric shutting, can only open a office fan simultaneously.
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| CN201811121373.9A CN109236343B (en) | 2018-09-26 | 2018-09-26 | Pressure-suction switching positive-pressure ventilation method for tunneling head |
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| CN201811121373.9A CN109236343B (en) | 2018-09-26 | 2018-09-26 | Pressure-suction switching positive-pressure ventilation method for tunneling head |
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| CN109236343B true CN109236343B (en) | 2020-08-04 |
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| CN110145355B (en) * | 2019-06-14 | 2024-05-17 | 华北理工大学 | Fire smoke flow drainage device and method for belt conveyor |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN2058428U (en) * | 1988-05-24 | 1990-06-20 | 煤炭工业部煤炭科学研究院南京研究所 | Explosion-proof local ventilator combined controlling box |
| RU2134353C1 (en) * | 1998-05-07 | 1999-08-10 | Санкт-Петербургский государственный горный институт им.Г.В.Плеханова (технический университет) | Method for regulation of thermal conditions in railway tunnels at winter period |
| CN2368978Y (en) * | 1998-11-25 | 2000-03-15 | 煤炭科学研究总院重庆分院 | Flexible guide wall-adhered duct |
| CN102418544A (en) * | 2011-10-28 | 2012-04-18 | 山西晋城无烟煤矿业集团有限责任公司 | Gas control and dust fall method for overlapped section of air barrels in excavation roadway |
| CN202731968U (en) * | 2012-07-30 | 2013-02-13 | 昆明理工大学 | Movable type wind tube |
| CN203783584U (en) * | 2013-12-24 | 2014-08-20 | 山东新阳能源有限公司 | Coal mine fully-mechanized excavation face short-distance comprehensive dust removal system |
| CN103883343B (en) * | 2014-03-24 | 2016-01-20 | 中国矿业大学 | Based on the coal mine main ventilator not blowing-out method of falling machine of adjusting rotor blade |
| CN104481570B (en) * | 2014-11-29 | 2016-09-14 | 彝良驰宏矿业有限公司 | A kind of down-hole dead face ventilating system |
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