Colloidal emulsion explosive with high storage stability and preparation method thereof

Abstract

The invention discloses a colloidal emulsion explosive with high storage stability and a preparation method thereof. The raw materials for preparing the emulsion explosive comprise ammonium nitrate, calcium nitrate, water, a compound emulsifier, compound wax and a special foaming agent. Wherein the composite emulsifier is a modified span-80 composite emulsifier obtained by carrying out esterification reaction on an anionic carboxylate emulsifier and multiple hydroxyl sites of span-80, and the composite emulsifier has high molecular weight, so that the space volume of a lipophilic group is increased, and an interfacial film is tighter; the special foaming agent is composed of sodium nitrite, zinc nitrate, gelatin peptone, Tween 80, phosphoric acid, urea and water, the gelatin peptone is a green pure natural raw material, the surface tension of an emulsion matrix is effectively reduced, the contact area of the foaming agent and the emulsion matrix is increased, the foaming efficiency is catalyzed by zinc nitrate, and bubbles are good in stability and not prone to escaping due to Tween 80. The use of the compound emulsifier and the special foaming agent improves the blasting performance and storage stability of the emulsion explosive.

Description

Technical Field

[0001] The invention relates to the technical field of emulsion explosives, in particular to a colloidal emulsion explosive with high storage stability. Background Art

[0002] Emulsion explosive is a mixed explosive, usually an oil-in-water emulsion explosive formed by uniformly dispersing an inorganic oxidant salt solution in an oil phase continuous medium of porous materials such as bubbles or hollow glass microspheres under the action of an emulsifier. The components of emulsion explosives include: oxidizer, combustible agent, emulsifier, sensitizer, foaming agent, stabilizer, etc. For a long time, in order to improve the blasting ability and storage stability of emulsion explosives, technicians have used various means to improve the emulsification quality and thus improve the blasting ability and storage stability of emulsion explosives. However, various conditions have caused the performance of emulsion explosives to fail to meet modern requirements. Therefore, there is an urgent need for an emulsion explosive with good stability and blasting properties to meet contemporary needs. Summary of the invention

[0003] In view of the above defects, the present invention provides a method for preparing a colloidal emulsion explosive with high storage stability, wherein the raw materials for preparing the emulsion explosive are composed of ammonium nitrate, calcium nitrate, water, a composite emulsifier, a composite wax, and a special foaming agent. The emulsion explosive of the present invention has good blasting performance and storage stability.

[0004] The weight fractions of the raw materials for preparing the emulsion explosive with high storage stability are as follows: 72-78 parts of ammonium nitrate, 7-10 parts of calcium nitrate, 8-12 parts of water, 2.2-2.8 parts of composite emulsifier, 2.5-4 parts of composite wax, and 0.2-0.4 parts of special foaming agent.

[0005] The method for preparing an emulsion explosive with high storage stability comprises the following steps: (1) Preparation of water phase: water is poured into the tank and steam is pressurized to maintain the temperature at 100°C and the steam pressure at 0.5 MPa; calcium nitrate is first added to the tank and stirred to dissolve, then ammonium nitrate is added and stirred at 100°C to dissolve; (2) Preparation of oil phase: Mix the composite wax and the composite emulsifier, and continue stirring to dissolve them; (3) Emulsification and sensitization: The water phase and the oil phase are mixed in a ratio of 9:1 for emulsification, then cooled and a special foaming agent is added for sensitization, and finally the mixture is loaded and packaged.

[0006] Specifically, the composite emulsifier is a composite emulsifier obtained by esterifying an anionic carboxylate emulsifier with multiple hydroxyl sites of Span-80 to obtain a modified Span-80; the preparation method of the composite emulsifier is to weigh sodium rosinate and Span-80 in a molar mass ratio of 1-5:1, respectively, and heat them at 60-80°C for 6-8h under the catalysis of concentrated sulfuric acid to obtain modified Span-80.

[0007] Specifically, the weight percentages of the components of the special foaming agent are as follows: sodium nitrite: 10-15%, zinc nitrate: 1-2%, gelatin peptone: 0.2-0.5%, Tween 80: 2-3%, phosphoric acid: 10-15%, urea: 5-10%, water: 54.5-71.8%; the preparation method of the special foaming agent is: step 1: adding water and Tween 80 and stirring for 20 minutes; step 2: adding sodium nitrite, zinc nitrate, phosphoric acid and urea and stirring for 1-2 hours; step 3: adding gelatin peptone and stirring for 1.5-2 hours until there is no micelle to obtain the special foaming agent for emulsion explosives.

[0008] Specifically, sensitization is achieved by transferring the emulsified matrix of the water phase and the oil phase into a sensitizer and spraying a special foaming agent through stirring of the upper and lower layers of the sensitizer.

[0009] The beneficial technical effects of the present invention are as follows: (1) The traditional emulsifier Span-80 is a low molecular weight nonionic surfactant that is difficult to dissolve in water but easily soluble in hot oil and organic solvents. The emulsion explosive prepared by the emulsion has poor storage stability. The present invention obtains a high molecular weight modified Span-80 by esterifying an anionic carboxylate emulsifier (sodium rosin acid) with multiple hydroxyl sites of Span-80. The composite emulsifier containing the modified Span-80 increases the spatial volume of the lipophilic group and makes the interface film more compact.

[0010] (2) Traditional foaming agents are added with zinc nitrate, Tween 80 and gelatin peptone. Among them, gelatin peptone is a green and pure natural raw material, which effectively reduces the surface tension of the emulsified matrix and increases the contact area between the foaming agent and the emulsified matrix. Zinc nitrate catalyzes the foaming efficiency, and Tween 80 makes the bubbles stable and not easy to escape. Adding the above three components to the foaming agent reduces the wear of equipment in the process of preparing emulsion explosives. (3) The addition of composite emulsifier and special foaming agent during the preparation of colloidal emulsion explosives improves the blasting performance and storage stability of the emulsion explosives. DETAILED DESCRIPTION

[0011] The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0012] Example 1: Emulsion explosive 1 (adding composite emulsifier, and using traditional foaming agent as foaming agent) (1) Preparation of aqueous phase: 8 parts of water by weight are injected into the tank body and steam pressurized to maintain the temperature at 100°C and the steam pressure at 0.5Mp; first, 7 parts of calcium nitrate by weight are added to the tank body and stirred to dissolve, and then 78 parts of ammonium nitrate by weight are added and stirred at 100°C to dissolve; wherein the ammonium nitrate is an aqueous solution of ammonium nitrate with a mass content of 90%; the concentration of calcium nitrate is 30%; (2) Preparation of oil phase: 2.5 parts by weight of composite wax and 2.2 parts by weight of composite emulsifier are mixed, stirred continuously, and dissolved; wherein the composite emulsifier is a composite emulsifier of modified Span-80 obtained by esterification reaction between anionic carboxylate emulsifier and multiple hydroxyl sites of Span-80; the specific preparation method of the composite emulsifier is to weigh sodium rosinate and Span-80 in a molar mass ratio of 5:1, respectively, and heat them at 60°C for 8 hours under the catalysis of 98% concentrated sulfuric acid to obtain modified Span-80; (3) Emulsification and sensitization: The water phase and the oil phase are mixed in a ratio of 9:1 for emulsification, and then cooled and transferred into a sensitizer. Then, 0.4 parts by weight of a traditional foaming agent is added and sprayed evenly. After stirring and sensitization in the upper and lower layers of the sensitizer, the mixture is loaded and packaged. The components of the traditional foaming agent include sodium nitrite: 10%, phosphoric acid: 10%, urea: 5%, and water: 75%.

[0013] Example 2: Emulsion explosive 2 (adding a special foaming agent and using a conventional emulsifier) (1) Preparation of aqueous phase: 8 parts of water by weight are injected into the tank body and steam pressurized to maintain the temperature at 100°C and the steam pressure at 0.5Mp; first, 7 parts of calcium nitrate by weight are added to the tank body and stirred to dissolve, and then 78 parts of ammonium nitrate by weight are added and stirred at 100°C to dissolve; wherein the ammonium nitrate is an aqueous solution of ammonium nitrate with a mass content of 90%; the concentration of calcium nitrate is 30%; (2) Preparation of oil phase: Mix 2.5 parts by weight of composite wax and 2.2 parts by weight of traditional emulsifier Span-80, and continue stirring to dissolve; (3) Emulsification and sensitization: The aqueous phase and the oil phase are mixed in a ratio of 9:1 for emulsification, and then cooled and transferred into a sensitizer, and 0.4 parts by weight of a special foaming agent is added and sprayed evenly, and sensitized by stirring in the upper and lower layers of the sensitizer, and finally loaded and packaged; wherein, the composition of the special foaming agent is sodium nitrite: 10%, zinc nitrate: 1%, gelatin peptone: 0.2%, Tween 80: 2%, phosphoric acid: 10%, urea: 5%, water: 71.8%, and the specific preparation method is step 1: adding water and Tween 80 and stirring for 20 minutes; step 2: adding sodium nitrite, zinc nitrate, phosphoric acid and urea and stirring for 2 hours; step 3: adding gelatin peptone and stirring for 2 hours until there is no micelle to obtain the special foaming agent for emulsion explosives.

[0014] Example 3: Emulsion explosive 3 (addition of composite emulsifier and special foaming agent) (1) Preparation of aqueous phase: 8 parts of water by weight are injected into the tank body and steam pressurized to maintain the temperature at 100°C and the steam pressure at 0.5Mp; first, 7 parts of calcium nitrate by weight are added to the tank body and stirred to dissolve, and then 78 parts of ammonium nitrate by weight are added and stirred at 100°C to dissolve; wherein the ammonium nitrate is an aqueous solution of ammonium nitrate with a mass content of 90%; the concentration of calcium nitrate is 30%; (2) Preparation of oil phase: 2.5 parts by weight of composite wax and 2.2 parts by weight of composite emulsifier are mixed, stirred continuously, and dissolved; wherein the composite emulsifier is a composite emulsifier of modified Span-80 obtained by esterification reaction between anionic carboxylate emulsifier and multiple hydroxyl sites of Span-80; the specific preparation method of the composite emulsifier is to weigh sodium rosinate and Span-80 in a molar mass ratio of 5:1, respectively, and heat them at 60°C for 8 hours under the catalysis of 98% concentrated sulfuric acid to obtain modified Span-80; (3) Emulsification and sensitization: The aqueous phase and the oil phase are mixed in a ratio of 9:1 for emulsification, and then cooled and transferred into a sensitizer, and 0.4 parts by weight of a special foaming agent is added and sprayed evenly, and sensitized by stirring in the upper and lower layers of the sensitizer, and finally loaded and packaged; wherein, the composition of the special foaming agent is sodium nitrite: 10%, zinc nitrate: 1%, gelatin peptone: 0.2%, Tween 80: 2%, phosphoric acid: 10%, urea: 5%, water: 71.8%, and the specific preparation method is step 1: adding water and Tween 80 and stirring for 20 minutes; step 2: adding sodium nitrite, zinc nitrate, phosphoric acid and urea and stirring for 2 hours; step 3: adding gelatin peptone and stirring for 2 hours until there is no micelle to obtain the special foaming agent for emulsion explosives.

[0015] Example 4: Performance Test The performance was tested and the results are shown in the following table:

[0016] Comparative Example 1: The emulsion explosive was prepared by using a conventional emulsifier (component: Span-80) and a conventional foaming agent (component: sodium nitrite: 10%, phosphoric acid: 10%, urea: 5%, water: 75%). The preparation steps of the colloidal emulsion explosive were the same as those in Examples 1-3, and the performance was tested. The results are shown in the following table:

[0017] By comparison, it can be seen that the preparation process of the emulsion explosive of the present invention adopts a combination of a composite emulsifier and a special foaming agent, which improves the blasting performance and storage stability of the emulsion explosive.

[0018] The present invention is not limited to the above embodiments. For those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements are also considered to be within the scope of protection of the present invention. The preparation of emulsion explosives in this specification is a prior art known to professional and technical personnel in the field, and no further elaboration is given here.

Claims

1. A method for preparing a colloidal emulsion explosive with high storage stability, characterized in that: The raw materials for preparing emulsion explosives are composed of ammonium nitrate, calcium nitrate, water, composite emulsifier, composite wax and special foaming agent.

2. The method according to claim 1, characterized in that The weight fractions of the raw materials are as follows: 72-78 parts of ammonium nitrate, 7-10 parts of calcium nitrate, 8-12 parts of water, 2.2-2.8 parts of composite emulsifier, 2.5-4 parts of composite wax, and 0.2-0.4 parts of special foaming agent.

3. The method according to claim 1, characterized in that The following steps are involved: (1) Preparation of water phase: water is poured into the tank and steam is pressurized to maintain the temperature at 100°C and the steam pressure at 0.5 MPa; calcium nitrate is first added to the tank and stirred to dissolve, then ammonium nitrate is added and stirred at 100°C to dissolve; (2) Preparation of oil phase: Mix the composite wax and composite emulsifier, and continue stirring to dissolve; (3) Emulsification and sensitization: The water phase and the oil phase are mixed in a ratio of 9:1 for emulsification, then cooled and a special foaming agent is added for sensitization, and finally the mixture is loaded and packaged.

4. The method according to claim 1, characterized in that The composite emulsifier is a composite emulsifier of modified Span-80 obtained by esterification reaction between anionic carboxylate emulsifier and multiple hydroxyl sites of Span-80.

5. The method according to claim 4, characterized in that The preparation method of the composite emulsifier is to weigh sodium rosinate and Span-80 in a molar mass ratio of 1-5:1, heat them at 60-80°C for 6-8h under the catalysis of 98% concentrated sulfuric acid to obtain modified Span-80.

6. The method according to claim 1, characterized in that The weight percentages of the components of the special foaming agent are as follows: sodium nitrite: 10-15%, zinc nitrate: 1-2%, gelatin peptone: 0.2-0.5%, Tween 80: 2-3%, phosphoric acid: 10-15%, urea: 5-10%, and water: 54.5-71.8%.

7. The method according to claim 6, characterized in that The preparation method of the special foaming agent is: Step 1: Add water and Tween 80 and stir for 20 minutes; Step 2: Add sodium nitrite, zinc nitrate, phosphoric acid and urea and stir for 1-2 hours; Step 3: Add gelatin peptone and stir for 1.5-2 hours until there is no micelle to obtain a special foaming agent for emulsion explosives.

8. The method as claimed in claim 3, wherein the sensitization is achieved by transferring the emulsified matrix of the water phase and the oil phase into a sensitizer and spraying a special foaming agent, and stirring the upper and lower layers of the sensitizer.

9. A colloidal emulsion explosive having high storage stability prepared by the method according to claim 1.

Images