RU2572328C2 - Explosives consisting of ammonium nitrate and liquid fuel - Google Patents

Abstract

FIELD: blasting operations.

SUBSTANCE: explosive with an oxygen balance of -3.5% to +3.5% consists of ammonium nitrate and liquid fuel, which it contains as mixtures of vegetable oils (VO) and diesel fuel (DF). The invention enables to use the renewable raw materials - VO. To prepare the compositions AC-VO-DF the simple bulk gravity mixers can be used. The calculations and experiments confirm that effectiveness of the mixtures of AC-VO-DF is as good as the mixtures of AC-VO, AC-DF (igdanite and granulite M), respectively. The environmental safety of the explosive compounds AC-VO-DF exceeds igdanite and the compositions AC-VO, as in case of their explosion a smaller discharge of toxic nitrogen oxides to the atmosphere is observed.

EFFECT: improvement of environmental friendliness.

2 tbl, 7 dwg

Description

The invention relates to industrial explosives (BB) and can be used in the mining industry for the development of mineral deposits on the earth's surface, in mines that are not dangerous for gas and dust, and during other blasting operations (pits, dams, etc.).

Since the mid 50-ies of the XX century, compositions based on ammonium nitrate (ammonium nitrate (AS)) and liquid fuel - oil products began to be used as mixed industrial explosives in Russia and abroad. In Russia, the first composition based on nuclear power plants and diesel fuel (DT) was called Igdanit [1]. Subsequently, such compounds in Russia were called AS-DT, and other petroleum products (kerosene, industrial oils, fuel oil, etc.) were also understood as DT. In the United States and abroad, such compounds were called ANFO ("ammonium nitrate - fuel oil", which translates as "ammonium nitrate - oil product").

The compositions of ANFO, which use speakers of different porosity, include compositions according to the patent US 3781180 (12.25.1973) [2], which, like domestic compositions AC-DT, are analogues of the present invention. The disadvantage of such compositions is that liquid fuels and petroleum products are non-renewable sources of raw materials. The disadvantages of some petroleum products, in particular DT, in Igdanit-type compounds also include the fact that after mixing the components, partial drainage of petroleum products is observed [3], especially in the warm season. The undoubted advantage of these compositions is that for mixing the components, it is sufficient to use the simplest volume gravity mixers: cylindrical, such as a “drunken” barrel, such as a “concrete mixer”, etc. [4].

Patent WO 98/00374 (8.01.1998) [5] (prototype) proposes compositions of AS and liquid fuel in the form of natural (natural) fats, including oils (peanut, soy, flaxseed, corn, sunflower, rapeseed, etc. ), which in Russia are known as vegetable oils (RM) [6]. The disadvantage of the prototype is that for the uniform distribution of RM over the AC, ensuring maximum explosion efficiency, in the manufacture of mixtures of AC-PM requires a whole range of measures:

1) gas supply for the distribution of PM;

2) the use of a suitable solvent, which is removed after mixing;

3) the implementation of mixing when applying heat, i.e. in a heated mixer;

4) pre-heating PM before mixing.

Therefore, the preparation of AC-PM mixtures according to the prototype is much more complicated in hardware design than the preparation of AC-DT mixtures (ANFO).

The undoubted advantage of the prototype in contrast to other analogues is that all RM are renewable sources of raw materials,

environmentally friendly, because in contact with the environment are capable of undergoing biochemical decomposition [6].

The technical result of the invention is to eliminate the disadvantages of the prototype and analogues while maintaining the advantages of the prototype and analogues.

As a result of the studies, it was shown that the technical result is achieved when using RM-DT mixtures as liquid fuel, i.e. obtaining explosive composition AC-RM-DT.

To obtain PM-DT mixtures, various vegetable oils can be used. PM differ in nutritional value, taste [6], but as combustible they are practically equivalent to each other. All PMs are glycerides of higher saturated and unsaturated fatty acids, usually with an even number of carbon atoms in the chain, mainly C ₁₆ and C ₁₈ [6], and have a close elemental composition (percentage of carbon C, hydrogen H and oxygen O) [7]. Mixtures of RM-DT as combustible in energy potential in compositions with AS are equivalent to DT. Indeed, the thermochemical calculations carried out by the applicant according to the method of FSUE GosNII Kristall [8], which are presented in table. 1 "The calculated explosive characteristics of the compositions" AC - liquid fuel "with zero oxygen balance", confirm the above. The results are shown in table. 1 are in good agreement with experimental data for igdanite TU [1]: heat of explosion _adult Q = 904 kcal / kg, the volume of the gaseous explosion products V = 980 ... 990 l / kg.

; a, b, d - число атомов углерода, водорода и кислорода в молекуле ВВ, 16 - атомная масса кислорода, М - молярная масса ВВ [9]) имеют максимальную теплоту взрыва [9-11]. Отклонение в содержании компонентов в составах (по прототипу [5] АС - 93-95 мас. %, жидкое горючее - 7-5 мас. % или по аналогу [1] АС - 94-95 мас. %, жидкое горючее - 6-5 мас. %) связано с технологическими причинами и, в частности, обусловлено неточностью их дозировки при массовом изготовлении составов. Увеличение или уменьшение содержания АС на 1 мас. % относительно состава с КБ=0% приводит в зависимости от типа жидкого горючего соответственно к увеличению или уменьшению КБ на 3,1% для составов АС-РМ и на 3,5% для составов АС-ДТ. Следовательно, вместо интервалов процентного содержания АС и горючего в композиции можно указывать значение КБ состава.It is known that compounds with zero oxygen balance

; a, b, d are the number of carbon, hydrogen and oxygen atoms in the explosive molecule, 16 is the atomic mass of oxygen, M is the molar mass of explosives [9]) have a maximum heat of explosion [9-11]. Deviation in the content of components in the compositions (prototype [5] AC - 93-95 wt.%, Liquid fuel - 7-5 wt.% Or by analogy [1] AC - 94-95 wt.%, Liquid fuel - 6- 5 wt.%) Is associated with technological reasons and, in particular, due to the inaccuracy of their dosage in the mass production of compositions. The increase or decrease in the content of AC per 1 wt. % relative to the composition with KB = 0%, depending on the type of liquid fuel, respectively, leads to an increase or decrease in CB by 3.1% for AC-PM compositions and by 3.5% for AC-DT compositions. Therefore, instead of intervals of the percentage of AS and fuel in the composition, you can specify the value of the KB composition.

Of the RM, rapeseed oil is the most economically preferred. Rapeseed oil is considered both in Russia and abroad as a basis for obtaining biodiesel fuels instead of diesel fuel [12].

The compositions "AS - liquid fuel" for laboratory tests were prepared by the applicant in a volumetric gravity mixer model C 2.0 LLC Vibrotehnik at a temperature of + 20 ... + 23 ° C.

Applicant used AC:

granular GOST 2-85 grades A (hereinafter - AC (1)) and B (hereinafter - AC (2)), modified porous TU 2143-029-00203795-2005 (hereinafter - AC (3)),

waterproof iron-coated GOST 14702-79 of ZhVG brands (hereinafter - AS (4)) and ZhVK (hereinafter - AS (5))

and liquid fuels:

DT EURO GOST R 52368-2005 (grade C, type II),

unrefined corn oil GOST 8808-2000 (grade P),

unrefined linseed oil GOST 5791-81 (second grade),

unrefined sunflower oil GOST R 52465-2005 (for industrial processing),

unrefined rapeseed oil GOST R 53457-2009 (for industrial processing).

The mixing time, which ensures uniform distribution of liquid fuel over the AS, was for: DT - 11 ... 11.5 min; RM-DT (50 wt.%: 50 wt.%) - 12 ... 12.5 min; RM-DT (75 wt.%: 25 wt.%) - 13 ... 13.5 min; RM-DT (90 wt.%: 10 wt.%) - 13.5 ... 14 min (a further increase in time does not change the quality of mixing). To obtain a high-quality mixture "AC - rapeseed oil" (in accordance with the composition of the prototype) fails during mixing 70 minutes (see photo in Fig. 1 "Distribution of rapeseed oil over AC after mixing at a temperature of + 20 ... + 23 ° C" ) In fig. Figure 1 shows the areas of non-uniform distribution of rapeseed oil (marked by arrows). That is why the prototype provides a set of measures to ensure uniform distribution of PM in the AC.

At a temperature of -20 ° C (cooling in the freezer), for example, corn, linseed, sunflower and rapeseed oils are not only mixed with AC, but it will be very difficult to extract from containers without heating, as they lose fluidity (see photos in Fig. 2 “Consistency of vegetable oils at a temperature of minus 20 ° C”; 1 - linseed oil, 2 - corn oil, 3 - sunflower oil, 4 - rapeseed oil). Thus, the use of the simplest in design gravity mixers does not allow to prepare high-quality compositions of AC-RM prototype.

Studies have shown that, unlike pure PM, their mixtures with DT (for example, rapeseed oil-DT 50 wt.%: 50 wt.%) At -20 ° C have a fluidity quite acceptable for mixing with AC (see photo in Fig. 3 “Consistency of mixed liquid combustible rapeseed oil - DT 50 wt.%: 50 wt.% At a temperature of minus 20 ° C”).

Since the disadvantage of AS-DT mixtures is the draining of DT [3] with AS GOST 2-85 and GOST 14702-79, the applicant used the express method to compare the retention times of liquid fuel in AS-RM-DT compositions with KB = 0% and in Igdanite . To do this, 30 g of the composition after mixing were placed in a glass burette, which simulates a well. A time was fixed for which 0.05 ml of liquid fuel was collected in the lower part of the burette, which amounts to a loss of 2.3% of the mass of liquid fuel in the composition (see photo in Fig. 4 “Drainage of Igdanit diesel fuel”). Retention times were (average rounded values from 3 experiments):

1) for Igdanit: at the AC (1) - 19 min, at the AC (2) - 18 min, at the AC (4) - 43 min;

2) for the composition of AS (1) - rapeseed oil-DT (liquid fuel - 50 wt.%: 50 wt.%) - 86 min .;

3) for the composition of AS (2) - rapeseed oil-DT (liquid fuel - 75 wt.%: 25 wt.%) - 144 min .;

4) for the composition of AS (4) - rapeseed oil-DT (liquid fuel - 90 wt.%: 10 wt.%) - 413 min.

Thus, in terms of the retention time of liquid fuel at AS GOST 2-85 and GOST 14702-79, the compositions of AS-RM-DT are significantly superior to Igdanit.

The problem of draining DT is irrelevant for AC-DT compositions prepared on a porous AS [9-11]. Among such compositions is, for example, Granulit M GOST 21987-76, which has the same percentage of AS and DT as Igdanit [9-11, 13]. The applicant compared the retention times of liquid fuel for Granulite M (KB = 0%; AS (3); liquid fuel - DT) and compositions AC-PM-DT (KB = 0%; AS (3); liquid fuel: 1) rapeseed oil - 90 wt. %, DT - 10 wt. %, 2) sunflower oil - 75 wt. %, DT - 25 wt. %, 3) corn oil - 50 wt. %, DT - 50 wt. %). Mixing times: Granulite M - 10 min., Compositions AC-RM-DT - 12 min. Neither Granulite M nor AC-PM-DT formulations detected any run-off of liquid fuel in 5 days.

Thus, the use of a porous AS is equally effective for both AC-DT and AC-PM-DT compositions.

Good results were obtained by the applicant for compositions with KB = 0%, in which a mixture of 60 wt. % porous AS (3) and 40 wt. % granular AS (AS (2), AS (4)). The following comparative retention time data were obtained for the compositions AC-DT and AC-RM-DT:

1) for compositions: AC (3) -AC (2) -DT - 28 hours, AC (3) -AC (4) -DT - 59 hours;

2) for the composition of AC (3) -AC (2) - rapeseed oil-DT (liquid fuel - 90 wt.%: 10 wt.%) - 68 hours;

3) for the composition of AC (3) -AC (2) - sunflower oil-DT (liquid fuel - 75 wt.%: 25 wt.%) - 57 hours;

4) for the composition of AC (3) -AC (4) - corn oil-DT (liquid fuel - 50 wt.%: 50 wt.%) - 102 hours

Thus, in the retention time, the compositions of AC-RM-DT on a mixture of two AS are significantly superior to the compositions of AC-DT.

For mixtures "AC - liquid fuel", the brisance was determined by crimping lead cylinders (Hess test) according to GOST 5984-99 (version 3, steel ring, additional detonator). The experimental results are given in table. 2 "The brisance of explosive compositions" AC - liquid fuel "with zero oxygen balance." In the table. Figure 2 shows the average values of brisance from two experiments.

The analysis presented in table. 2 of the data shows that in terms of brisance the compositions of AC-RM-DT not only are not inferior to the compositions of AC-RM (prototype) and AC-DT (analogue), but also somewhat surpass the latter.

The applicant conducted comparative full-scale tests of explosive compositions "AS - liquid fuel" with zero KB:

1) AC-DT (Igdanit; analogue):

AS brand B (GOST 2-85) - 94.22 wt. %

DT EURO grade C, type II (GOST R 52368-2005) - 5.78 wt. %;

2) AC-RM (composition in accordance with the prototype):

AS brand B (GOST 2-85) - 93.52 wt. %

unrefined rapeseed oil for industrial processing (GOST R 53457-2009) - 6.48 wt. %;

3) AS - rapeseed oil-DT:

AS brand B (GOST 2-85) - 93.60 wt. %

unrefined rapeseed oil for industrial processing (GOST R 53457-2009) - 5.76 wt. %

DT EURO grade C, type II (GOST R 52368-2005) - 0.64 wt. %

(ratio in liquid fuel: rapeseed oil - 90 wt.%, DT - 10 wt.%);

4) AS - rapeseed oil-sunflower oil-DT:

AS brand B (GOST 2-85) - 93.60 wt. %

unrefined rapeseed oil for industrial processing (GOST R 53457-2009) - 2.88 wt. %

unrefined sunflower oil for industrial processing (GOST R 52465-2005) - 2.88 wt. %

DT EURO grade C, type II (GOST R 52368-2005) - 0.64 wt. %

(ratio in liquid fuel: rapeseed oil - 45 wt.%, sunflower oil - 45 wt.%, DT - 10 wt.%).

The compositions were prepared according to the traditional technology using volumetric gravity mixers of the OSG-250 brand approved by Rostekhnadzor for the preparation of Igdanit-type explosive compositions, into which either AC and DT, or AC and RM, or AC, RM and DT were loaded in the required proportions.

The tests were carried out in July 2013 (air temperature + 29 ... + 34 ° C) at the Bogatyr quarry of Zhigulevsky Lime Plant CJSC.

Undermined rock mass (limestones and dolomites belonging to categories VIII-X according to SNiP IV-2-82 classification, average density - 2.4 g / cm ³ , average porosity - 11.63%) consisted of 18 m × 78 blocks m × 10 m. In the blocks, 39 wells were drilled (3 rows of 13 wells) with a diameter of 215 mm with a grid of wells of 6 m × 6 m. The height of the step is 10 m, the depth of the wells is 11.5 m, the depth of the drill is 1.5 m. The volume of rock mass minus the volume of wells was 14025 m ³ . The capacity of 1 running meter of a well was 38-39 kg of explosives with a charge height of 6 m (i.e. 228-234 kg of explosives per well, taking into account one gunman per well of cartridge ammonite No. 6ZHV (GOST 21984-76) weighing 1 kg) , stemming height - 5.5 m. The militants were installed in the lower part of the charge columns, dropped on one thread of the DSHE-12 detonating cord (GOST 6196-78), which was driven by an ED-8 electric detonator (GOST 9089-75). The blasting pattern is decent (13 wells in a row) short-delayed, with a slowdown between steps of 42 ms. The number of deceleration steps is 2. As the moderator were used

RPE-2 pyrotechnic relays (TU 7287-120-07513406-99) (1 pc. for each deceleration stage).

The following has been experimentally established.

1) For all four compounds "AS - liquid fuel":

- explosion collapse - compact, the height of the collapse does not exceed the height of the ledge;

- there is no ejection of rock mass for the last row of wells;

- residual phenomena of burnout of explosives and failures during inspection of the blasted rock mass were not detected;

2) When testing the compositions of AC-RM-DT, a decrease in the content of nitrogen oxides in gaseous products of the explosion was recorded in comparison with the compositions of AC-PM (prototype) and AC-DT (analogue Igdanit), as evidenced by the absence of a pronounced so-called "fox tail "Nitrogen oxides (see photos taken in video shooting in Fig. 5" Testing the explosive composition of the AC-PM type ", Fig. 6" Testing the explosive composition of the AC-DT type (Igdanit) "and Fig. 7" Testing the explosive composition of the AC-PM type -DT ");

3) When shipped for processing rock mass exploded using AS-RM-DT explosive compositions, an improved quality of crushing and working out of the sole is noted in comparison with AS-RM (prototype) and AS-DT (analogue Igdanit) explosive compositions, in which crushing is satisfactory.

In general, the tests showed that, firstly, the mixed explosive compositions of the AS-RM-DT type are not inferior in effectiveness to the compositions of the AS-RM according to the prototype and industrial explosives - Igdanit (analog). Secondly, when the AS-RM-DT mixtures were detonated, it was visually found that the gaseous products of the explosion contained a much smaller amount of toxic nitrogen oxides compared with the compositions of AS-RM and AS-DT. This is due to the good quality of the mixing of the compositions AC-RM-DT in comparison with the prototype and significantly less runoff of liquid fuel with AS in the proposed compositions in comparison with the analogue Igdanit.

Thus, the task of the invention can be considered successfully solved. Unlike the prototype, for uniform distribution of liquid fuel over the AC and for obtaining high-quality explosive compositions “AC - liquid fuel”, there is no need to bubble the mass with gas, use solvents to be removed, use pre-heating PM and carry out mixing in a heated mixer, i.e. in the use of complex hardware design of the process of mixing components. Depending on the temperature conditions for blasting, changing the ratio between RM and DT, for the manufacture of compositions AC-RM-DT, you can use the simplest volume gravity mixers. Explosives consisting of nuclear power and liquid fuel RM-DT use mostly environmentally friendly renewable raw materials. In addition, it was shown that the use of RM-DT mixtures prevents the flow of liquid fuel and promotes uniform mixing of components (improving the quality of compositions), therefore, in terms of environmental safety, AS-RM-DT explosive compositions are superior to compositions

AC-RM and AC-DT. The explosion of AC-RM-DT results in a lower emission of toxic nitrogen oxides into the atmosphere compared to compositions of AC-RM and AC-DT.

Information sources

1) TU-GP-02. The explosive is igdanite. Technical conditions - M.: USSR Academy of Sciences, 1977 .-- 11 p.

2) Patent US 3781180 A. Ammonium nitrate - fuel oil composition containing ammonium nitrate prills of different porosity, hardness, and density. / P.S. Harrison, G. Harries (AU). - Appl. No. 140106. Filed 05/04/1971; Date of Patent 12/25/1973.

3) Rimarchuk B.I., Schwarzer V.Ya., Prilipenko V.D., Prilipenko E.D., Drobot V.A., Korostelev M.N. The use of a new elementary explosive - igdanit IVD-5 at iron ore enterprises of the Krivoy Rog basin. / Mountain news and analytical bulletin. 2005, No. 8. - M.: Mountain Book, 2005.S. 132-136.

4) Generals M.B. The main processes and apparatus technology industrial explosives: Textbook. manual for universities. - M.: IKC "Akademkniga", 2004. - 397 p.

5) Patent WO 98/00374 A1. Sprengstoff / H.H. Meyer (DE). - Internationales Aktenzeichen PCT / EP97 / 03374. Internationales Anmeldedatum 06/27/1997; Internationales Veröffentlichungsdatum 8.01.1998.

6) Chemical Encyclopedia in five volumes. T. 4. - M.: Big Russian Encyclopedia, 1995.S. 192-196.

7) Mysnik M.I., Svistula A.E. Analysis of the thermophysical properties of alternative fuels for internal combustion engines. / Polzunovsky Bulletin No. 1-2. - Barnaul: Altai State Technical University I.I. Polzunova, 2009.S. 37-43.

8) Kolganov E.V., Smirnov S.P., Smirnov A.S. Simple methods for calculating detonation characteristics and a general methodology for developing methods for estimating explosion parameters. Extreme conditions of a substance. Detonation. Shock waves. Proceedings of the International Conference "IX Khariton's Thematic Scientific Readings" (March 12-16, 2007). - Sarov: RFNC-VNIIEF, 2007.S. 144-146.

9) Dubnov L.V., Bakharevich N.S., Romanov A.I. Industrial explosives. - M .: Nedra, 1973. - 320 p.

10) Kolganov E.V., Sosnin V.A. Industrial explosives. - 2nd book: Compositions and properties. - Dzerzhinsk, Nizhny Novgorod Region: State Research Institute "Crystal", 2010. - 544 p.

11) Mikhailov Yu.M., Kolganov E.V., Sosnin V.A. Safety of ammonium nitrate and its use in industrial explosives. - Dzerzhinsk: LLC “Partner Plus”, 2008. - 304 p.

12) Markov V.A., Gayvoronsky A.I., Devyanin S.N., Ponomarev E.G. Rapeseed oil as an alternative fuel for diesel. / Magazine "Automotive Industry". No. 2, 2006. S. 1-4.

13) GOST 21987-76. Explosive industrial substances. Granulitis. Technical conditions - M .: IPK Publishing House of Standards, 2004. - 6 p.

Claims (1)

An explosive with an oxygen balance of -3.5% to + 3.5%, consisting of ammonium nitrate and liquid fuel, characterized in that it contains a mixture of vegetable oils and diesel fuel as a liquid fuel.

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