On-site mixed emulsion explosive and its application in smooth blasting

Abstract

The application discloses on-site mixed emulsion explosive and application thereof in smooth blasting, and the on-site mixed emulsion explosive contains the following raw materials in parts by weight: 60-80 parts of ammonium nitrate, 5-10 parts of sodium nitrate, 12-18 parts of water, 6-7 parts of mixed oil phase, 0.4-0.9 parts of sensitizer, 0.2-0.5 parts of accelerator, 5-12 parts of calcium chloride and 4-8 parts of sodium sulfate; the method steps of the application of the on-site mixed emulsion explosive in the smooth blasting are as follows: S1, arrangement of auxiliary holes, slotting holes, caving holes and peripheral holes; S2, on-site filling of the on-site mixed emulsion explosive is sequentially carried out on the auxiliary holes, the slotting holes, the caving holes and the peripheral holes by an on-site mixing vehicle, and a blasting network is formed; and S3, blasting construction is carried out in a delay segmented detonation mode. In the on-site mixed emulsion explosive, the detonation velocity regulator is mixed more uniformly, more detonation gas can be generated, and the crack propagation effect of a blast hole is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of smooth blasting, in particular to on-site mixed emulsion explosive and its application in smooth blasting. BACKGROUND

[0002] Smooth blasting refers to a blasting operation technique that dense blast holes are arranged along the excavation boundary, uncoupled charging or low-power explosives are used, and after the main blasting area is blasted, the shock wave and gas generated by the explosion of the explosives form a smooth and flat fracture profile in the medium. In tunnel or roadway excavation blasting engineering, in order to reduce the excessive damage of blasting to surrounding rock and ensure the safety of the roadway, smooth blasting technology is often used at the boundary of the excavation section.

[0003] At present, the construction site mainly uses standard charge diameter (32mm) of detonating cord segmented interval charging structure. According to the concentration of explosives, several explosive packs are fixed on bamboo strips at certain intervals, and are uniformly arranged in the blast hole. Detonating cord is used for one-time initiation, or inert materials are added in powdered emulsion explosive or ammonium oil explosive to prepare low-blast-speed explosives for smooth blasting, and the low-blast-speed explosives are coupled and filled.

[0004] The existing smooth blasting charging method has the following disadvantages:

[0005] (1) The traditional intermittent charging method has different crushing effects on the surrounding rock of the same blast hole. The pressure near the charging section is larger, the rock is excessively damaged, the rock near the air gap section is under-excavated, and the overall flatness of the surrounding rock after blasting is difficult to control. The intermittent charging structure is complex, the operation is tedious, more preparation work is needed before blasting, and in order to ensure the stability of the detonation, detonating cord is generally used for initiation, which is high in blasting cost.

[0006] (2) The inert material commonly added in explosives, such as expanded perlite, is harmful to the respiratory system of the human body, and this adding method is only suitable for powdered explosives. The gelatinous emulsion explosive needs to be fully stirred and mixed after adding, so as to form uniform low-blast-speed explosives. The existing mixing vehicle cannot realize the continuous and uniform addition of such inert materials.

[0007] (3) In actual blasting construction site, in order to achieve the effect of smooth blasting, different charging methods need to be implemented on the surrounding holes, auxiliary holes, caving holes, slotting holes and other blast holes, and even different types of explosives need to be selected. The intermittent charging or the preparation of low-blast-speed powdered explosives will increase the labor intensity of construction personnel, complicate the operation process, and affect the operation efficiency. SUMMARY

[0008] Based on the technical problems existing in the background art, the present application provides a field mixed emulsion explosive and its application in smooth blasting, the speed regulator is mixed more uniformly, and more explosion gas can be generated to improve the crack propagation effect of the blast hole.

[0009] The field mixed emulsion explosive provided by the present application contains the following raw materials in terms of weight parts: ammonium nitrate 60-80 parts, sodium nitrate 5-10 parts, water 12-18 parts, mixed oil phase 6-7 parts, sensitizer 0.4-0.9 parts, accelerator 0.2-0.5 parts, speed regulator A 5-12 parts, and speed regulator B 4-8 parts.

[0010] The speed regulator A is calcium chloride, and the speed regulator B is sodium sulfate.

[0011] Preferably, the sensitizer is sodium nitrite.

[0012] Preferably, the accelerator is citric acid and / or oxalic acid.

[0013] The application of the above field mixed emulsion explosive in smooth blasting provided by the present application has the following method steps:

[0014] S1: arrangement of auxiliary holes, slotting holes, caving holes and peripheral holes;

[0015] S2: filling of the field mixed emulsion explosive in the auxiliary holes, slotting holes, caving holes and peripheral holes by a field mixed vehicle in sequence, and forming a blasting network;

[0016] S3: blasting construction by using a delay segmented initiation method.

[0017] Preferably, the field mixed emulsion explosive filled in the auxiliary holes and slotting holes contains the following raw materials in terms of weight parts: ammonium nitrate 65-75 parts, sodium nitrate 6-9 parts, water 12-18 parts, mixed oil phase 6-7 parts, sensitizer 0.4-0.8 parts, and accelerator 0.2-0.4 parts.

[0018] Preferably, the field mixed emulsion explosive filled in the caving holes contains the following raw materials in terms of weight parts: ammonium nitrate 65-75 parts, sodium nitrate 6-9 parts, water 12-18 parts, mixed oil phase 6-7 parts, sensitizer 0.4-0.8 parts, accelerator 0.2-0.4 parts, speed regulator A 5-10 parts, and speed regulator B 4-6 parts.

[0019] Preferably, the field mixed emulsion explosive filled in the peripheral holes contains the following raw materials in terms of weight parts: ammonium nitrate 65-75 parts, sodium nitrate 6-9 parts, water 12-18 parts, mixed oil phase 6-7 parts, sensitizer 0.6-0.9 parts, accelerator 0.3-0.5 parts, speed regulator A 8-12 parts, and speed regulator B 6-8 parts.

[0020] The present application has the following beneficial technical effects:

[0021] 1. Uniformly introduce solid inert materials, realize on-site continuous preparation of emulsion explosive, and passivation process. The chemical reaction of sodium sulfate and calcium chloride is used to uniformly introduce solid inert material calcium sulfate in emulsion explosive with high viscosity, the strong water absorption of calcium chloride is used to increase the explosion gas of explosive, by adjusting the adding proportion of sodium sulfate and calcium chloride, the ratio of sodium nitrite and citric acid, the on-site preparation, continuous passivation and automatic coupling charging process of emulsion explosive in smooth blasting process are realized.

[0022] 2. Reasonably distribute energy and improve blasting effect. According to the effect of the blast hole, the emulsion explosive for smooth blasting is prepared and coupled on site: the explosive for slotting hole has high detonation velocity and concentrated energy, and is more easy to form free surface; the explosive for caving hole has appropriate energy, which can break rock and does not interfere with non-blasting area; the low energy density explosive is coupled and filled in peripheral hole, the blasting energy is uniformly distributed along the direction of blast hole, the rock profile after blasting is flat, the problem of overbreak and underbreak is effectively controlled, and the overall blasting effect is obviously improved.

[0023] 3. Simplify operation process and improve safety level. The on-site mixed emulsion explosive for smooth blasting is prepared according to the design purpose of the blast hole, which breaks the traditional charging and detonating mode of bamboo binding explosive and fuse, the mixed emulsion explosive for smooth blasting is prepared by the mixing vehicle, coupled and filled into the blast hole, the on-site mixed emulsion explosive for smooth blasting in tunneling is prepared by one vehicle, the process flow of on-site operation is simplified, the matrix has detonation sensitivity when filled into the blast hole, the direct contact between personnel and explosive is reduced, and the safety level and work efficiency in the construction process are improved.

[0024] 4. Wide application scenarios. The mixed vehicle can adjust the content of sensitizing agent, accelerant and detonation velocity adjusting agent, adjust the detonation performance of on-site mixed emulsion explosive such as detonation velocity and explosion volume, match various rock wave impedances, and adapt to smooth blasting in various complex operation environments. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The charging flow chart is provided for the present application;

[0026] Figure 2 The explosive explosion process diagram is provided for the present application;

[0027] Figure 3 The blasting crack propagation diagram is provided for the present application;

[0028] Figure 4 The blasting effect diagram is provided for the present application. DETAILED DESCRIPTION

[0029] The present application will be further described below in combination with specific embodiments.

[0030] Example 1

[0031] The on-site mixed emulsion explosive provided by the present application contains the following raw materials by weight: ammonium nitrate 70 kg, sodium nitrate 8 kg, water 16 kg, mixed oil phase 6.5 kg (purchased from Shanxi Jiulian Hongyuan Chemical Co., Ltd.), sodium nitrite 0.6 kg, citric acid 0.4 kg, calcium chloride 8 kg, and sodium sulfate 6 kg.

[0032] Example 2

[0033] The on-site mixed emulsion explosive provided by the present application contains the following raw materials by weight: ammonium nitrate 60 kg, sodium nitrate 5 kg, water 12 kg, mixed oil phase 6 kg, sodium nitrite 0.4 kg, citric acid 0.2 kg, calcium chloride 5 kg, and sodium sulfate 4 kg.

[0034] Example 3

[0035] The on-site mixed emulsion explosive provided by the present application contains the following raw materials by weight: ammonium nitrate 80 kg, sodium nitrate 10 kg, water 18 kg, mixed oil phase 7 kg, sodium nitrite 0.9 kg, oxalic acid 0.5 kg, calcium chloride 12 kg, and sodium sulfate 8 kg.

[0036] Application Example

[0037] The emulsion matrix, the prepared sensitizer, the accelerant, and the detonation velocity regulator are respectively added into the matrix box, the sensitizer box, the accelerant box, and the regulator box of the on-site mixed emulsion explosive truck for smooth blasting at the ground station. The mixed truck for smooth blasting drives to the blasting operation surface, the pipe feeder and the charging pipe are lifted to the vicinity of the blast hole by the lifting and rotating arm device, the charging pipe is aligned with the blast hole, the pipe feeder is started, the charging pipe is pushed to the bottom of the blast hole, the charging amount is set according to the depth of the blast hole, and the content of the sensitizer, the accelerant, and the detonation velocity regulator is adjusted according to the type of the blast hole, so as to prepare the on-site mixed emulsion explosive for smooth blasting with different detonation performances. The on-site charging process flow is shown in Figure 1 .

[0038] (1) Due to the clamping effect of the rock, the blasting rock breaking process of the slotting hole is very difficult, and the rock breaking of the slotting hole determines the blasting effect of the subsequent other blast holes to a certain extent. The auxiliary hole is used to further expand the free surface formed by the blasting of the slotting hole, and has a throwing effect on the rock after blasting. Therefore, high detonation velocity and high explosive force emulsion explosive needs to be filled in the slotting hole and the auxiliary hole, and the formula of the on-site mixed emulsion explosive for the slotting hole and the auxiliary hole is as follows: ammonium nitrate 70 kg, sodium nitrate 7 kg, water 16 kg, mixed oil phase 6 kg, sodium nitrite 0.7 kg, citric acid 0.3 kg, and no detonation velocity regulator is added.

[0039] Start the charging program, open the latex valve, lubricating water valve, accelerator valve, sensitizer valve, start the latex pump, lubricating water pump, accelerator pump, sensitizer pump, fill the high explosive needed for the slotting hole and auxiliary hole, set the blast speed regulator delivery ratio to 0, the latex matrix, accelerator and sensitizer are delivered according to the system setting ratio, the latex pump flow is automatically counted according to the latex matrix flow meter, and the sensitizer and accelerator are measured by the flow meter. A water ring resistance device is provided between the latex matrix pump and the inlet of the drug delivery pipe to ensure that the latex matrix is smoothly delivered in the drug delivery pipe. The latex matrix, accelerator and sensitizer are fully mixed by the static mixer at the end, the mixed fluid is pushed into the blast hole and reacts completely, and the uniform sensitization forms the on-site mixed emulsion explosive for the slotting hole and auxiliary hole.

[0040] (2) After blasting through the slotting hole and auxiliary hole, there is enough free surface, and the caving hole is more likely to form a large volume of blasting crater in the free surface direction, so a certain amount of blast speed regulator can be added to limit the performance of the explosive filled in the caving hole, reduce the disturbance of the explosion to the rock mass outside the construction area, and the formula of the emulsion explosive mixed on site for the caving hole is ammonium nitrate 65 kg, sodium nitrate 6 kg, water 12 kg, mixed oil phase 6 kg, sensitizer 0.8 kg, citric acid 0.2 kg, blast speed regulator A 6 kg, and blast speed regulator B 4 kg. The peripheral hole is mainly to ensure that the post-blast roadway section and shape meet the design requirements, and the surrounding rock can form a smooth contour surface, so the explosive filled in the peripheral hole needs to add blast speed regulator, and increase the proportion of sensitizer and accelerator, which increases the water content of the explosive, reduces the energy density per unit volume of the explosive, appropriately reduces the explosive velocity, and increases the explosive volume. The formula of the emulsion explosive mixed on site for the peripheral hole is ammonium nitrate 65 kg, sodium nitrate 6 kg, water 12 kg, mixed oil phase 6 kg, sensitizer 0.6 kg, accelerator 0.4 kg, blast speed regulator A 10 kg, and blast speed regulator B 7 kg.

[0041] Start the charging program, set different sensitizing agent, accelerator, blast speed regulator delivery ratios according to the type of blast hole, open the latex valve, lubricating water valve, accelerator valve, sensitizer valve, blast speed regulator valve, start the latex pump, lubricating water pump, accelerator pump, sensitizer pump and blast speed regulator pump, and deliver each raw material according to the set ratio. After the accelerator, blast speed regulator B and the matrix are mixed, they are delivered to the water ring resistance device at the inlet of the drug delivery pipe by the latex matrix pump, the sensitizer, blast speed regulator A and lubricating water enter the three adding inlets of the water ring device respectively, and then pass through the static mixer at the end of the pipeline. Regulator A reacts with regulator B, sensitizer reacts with accelerator, calcium sulfate microcrystals and sodium chloride are gradually formed inside the matrix, the remaining calcium chloride absorbs water to form a liquid film, which is wrapped in the matrix, the mixed fluid is quickly sensitized and foamed after being filled into the blast hole, forming the emulsion explosive mixed on site for the caving hole and peripheral hole.

[0042] The pipe feeder and the reel will automatically collect the pipe according to the set charging speed, automatically measure the charging amount, and automatically stop when reaching the set value. After the blast hole is charged, the charging pipe is recycled for the next blast hole cycle filling. Due to the different sensitization speeds of the sensitizing agent in each blast hole, the foaming speed of the explosive in the peripheral hole is the fastest, and the auxiliary hole- slot hole- collapse hole- peripheral hole sequence is adopted for charging, and the final explosion result is as shown in Figure 4 .

[0043] As shown in Figure 2 , the explosion reaction process of the site mixed emulsion explosive with the addition of the detonation velocity regulator is observed by using the static caustics instrument. It can be found that the caustic spot is the stress concentration point during the explosion, the crack expands from here, the detonation gas wedges into the crack, and the duration of crack growth is prolonged.

[0044] Figure 3 The explosion effect of the emulsion explosive with the addition of the detonation velocity regulator and the emulsion explosive without the addition of the detonation velocity regulator in the organic glass plate is shown in the figures. It can be seen that the detonation gas of the site mixed emulsion explosive after the addition of the detonation velocity regulator increases, and the crack expansion effect is better.

Claims

1. On-site mixed emulsion explosives, characterized in that: The invention comprises the following raw materials in parts by weight: 60-80 parts of ammonium nitrate, 5-10 parts of sodium nitrate, 12-18 parts of water, 6-7 parts of mixed oil phase, 0.4-0.9 parts of sensitizer, 0.2-0.5 parts of accelerator, 5-12 parts of detonation velocity regulator A, and 4-8 parts of detonation velocity regulator B; The detonation velocity regulator A is calcium chloride, and the detonation velocity regulator B is sodium sulfate.

2. The on-site mixed emulsion explosive according to claim 1, characterized in that: The sensitizer is sodium nitrite.

3. The on-site mixed emulsion explosive according to claim 1, characterized in that: The accelerator is citric acid and / or oxalic acid.

4. The use of the on-site mixed emulsion explosive according to any one of claims 1 to 3 in smooth blasting, characterized in that: The steps are as follows: S1: Arrangement of auxiliary holes, slot holes, cave holes and peripheral holes; S2: Use an on-site mixing vehicle to sequentially load emulsion explosives into auxiliary holes, cut holes, cave holes and peripheral holes, and form a blasting network; S3: Use delayed segmented detonation method for blasting construction.

5. The use of the on-site mixed emulsion explosive in smooth blasting according to claim 3, characterized in that: The weight proportions of the on-site mixed emulsion explosives for filling the auxiliary holes and the slot holes are as follows: 65-75 parts of ammonium nitrate, 6-9 parts of sodium nitrate, 12-18 parts of water, 6-7 parts of mixed oil phase, 0.4-0.8 parts of sensitizer, and 0.2-0.4 parts of accelerator.

6. The use of the on-site mixed emulsion explosive in smooth blasting according to claim 3, characterized in that: The weight proportions of the on-site mixed emulsion explosive for filling the cave hole are: 65-75 parts of ammonium nitrate, 6-9 parts of sodium nitrate, 12-18 parts of water, 6-7 parts of mixed oil phase, 0.4-0.8 parts of sensitizer, 0.2-0.4 parts of accelerator, 5-10 parts of detonation velocity regulator A, and 4-6 parts of detonation velocity regulator B.

7. The use of the on-site mixed emulsion explosive in smooth blasting according to claim 3, characterized in that: The weight proportions of the on-site mixed emulsion explosives for filling the peripheral holes are: 65-75 parts of ammonium nitrate, 6-9 parts of sodium nitrate, 12-18 parts of water, 6-7 parts of mixed oil phase, 0.6-0.9 parts of sensitizer, 0.3-0.5 parts of accelerator, 8-12 parts of detonation velocity regulator A, and 6-8 parts of detonation velocity regulator B.

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