RU2288208C1 - Method of producing powder and ballistite propellant - Google Patents

Abstract

FIELD: production of solid fuels.

SUBSTANCE: method comprises supplying fibers of nitrocellulose, admixtures, combustion modifying agents, plasticizing agents, stabilizers of chemical stability to the boiler and mixing the components to produce a propellant mass. When mixing, 0.5-1.0-% water solution of polyacrylamide is uniformly added to the mixture subsequent to the introducing of the plasticizing agents. The mixing should last at least 10 min, and then the propellant mass is squeezed, rolled, and moulded to produce propellant blanks.

EFFECT: reduced consumption of metal compounds.

1 cl, 1 tbl

Description

The patented invention relates to the manufacture of gunpowder and ballistic type fuel, namely, their production methods, during the implementation of which a uniform distribution of finely dispersed components (solid additives) in the powder mass is ensured.

The invention can be used in the manufacture of charges for rocket engines of solid fuel (solid propellant rocket engines), for various auxiliary devices of rockets - on-board power supplies (gas generators), pressure accumulators, rocket stage separators, etc.

Most ballistic powders and fuels contain solid components in the form of fine powders, the uniform distribution of which provides the required set of output characteristics. However, in the process of manufacturing the fuel mass due to the difference in the density of solid additives and their adhesive ability to nitrocellulose (SC), a uniform distribution in the mass is not always ensured, in addition, there are losses of these additives. Various techniques are used to reduce losses and increase the adhesion of solid additives to SC fibers: introducing wetting agents, modifying catalysts by chemical deposition, etc.

Known methods for the manufacture of solid rocket fuels based on SC, providing for its modification by chemical deposition of metal compounds (lead, copper, etc.) on the fibers of the SC (patents: RU 2167137 from 06.29.1999, RU 2203872 from 04.07.2001) .

The disadvantages of these methods are:

1. High losses of scarce metal compounds during the manufacture of fuel in the phase of mixing the components ("cooking"). As a rule, depending on the equipment used and the specifics of preparing specific fuel formulations, they range from 5 to 20% or more.

2. Finely dispersed particles of metal compounds, weakly bonded with SC fibers in the process of fuel mass production (“cooking”), with squeezed waters fall into the technological waste water, which leads both to direct economic losses of scarce raw materials and additional costs associated with environmental sewage treatment. To a certain extent, this drawback is eliminated by the purposeful prefabrication of the fuel semi-finished product in a separate reactor in the form of SC with metal compounds planted by a chemical reaction at the molecular level (patent RU 2167137 of June 29, 1999). However, this method is associated with a significant increase in the cost of manufacturing fuel, and a significant increase in the duration of the technological process of its manufacture. In addition, in the manufacturing process of such a semi-finished product, the losses during the planting of metal compounds on the fibers of the NTs by this method are also large - up to 65%.

3. The fastening component used according to the patent RU 2203872 - latex is an energy-negative additive, remains in the final formulation of the fuel and impairs its energy characteristics.

In General, the known methods are distinguished by either the complexity and duration of the fuel manufacturing process, or high cost, which significantly increases the cost of its manufacture. As the closest to the patented technical solution, the invention according to patent RU 2167137 is selected as a prototype.

The technical task of the patented invention is the development of a method for the manufacture of gunpowder and ballistic type fuel, which reduces the loss of finely dispersed metal compounds and other solid additives (catalysts, combustion stabilizers, crystalline explosives, etc.), reduces the cost of manufacturing fuel, due to the reduction of direct costs for its manufacture, as well as the costs of environmental wastewater treatment, providing increased fuel energy and improved combustion characteristics.

The technical result of the invention is to develop a method for the manufacture of gunpowder and ballistic type fuel, including introducing into the digester and mixing in an aqueous medium components - nitrocellulose fibers, processing aids, combustion modifiers, plasticizers and chemical resistance stabilizers to obtain a fuel mass. In this case, when mixing the fuel components, after the plasticizers are introduced into the digester, a 0.5-1.0% aqueous solution of polyacrylamide (PAA) is uniformly introduced, after which they are mixed for at least 10 minutes. The temperature-time regimes for introducing and mixing the components, their order of entry, are carried out in the existing way for each composition of the powder and fuel. The amount of PAA solution to be added is selected for a specific brand of fuel taking into account the amount of metal compounds and other solid additives introduced into the formulation.

Further fuel processing (fuel mass extraction, rolling, pressing of fuel blanks) is carried out by known methods.

The essence of the patented method is to use in the process of mixing the components of gunpowder and fuels a technological additive in the form of an aqueous solution of PAA with active ionic ability, which, on the one hand, maximizes the deposition of metal compounds and other solid additives on NC fibers, and, on the other hand, indirectly increase the energy of powders and solid rocket fuel, due to the maximum removal of water-soluble PAA from the fuel formulation during the spin cycle. The deposition of solid particles is carried out by flocculation on the NC fibers due to the adsorption of PAA polymer on their surface.

The table shows examples of the implementation of the patented method.

The results of experimental checks of the patented method show that the introduction of PAA in the manufacture of fuel mass significantly reduces the loss of metal compounds and other solid additives due to the adsorption flocculation mechanism from 19.6 to 1.2-2.4% (see table). As a result, fuel compositions more reliably provide the required level of energy and ballistic characteristics. In addition, a significant reduction in pollution of process effluents, including salts of heavy metals, is achieved.

Table Name of operations Production Modes Prototype according to patent RU 2167137 According to the proposed technical solution Experience.I Experience. II 1. The deposition of copper oxide on the fibers of the NC Injection of SC into the water mixture in a ratio of 1:18 at a temperature of 85 ÷ 105 ° С of copper acetate - - 2. The deposition of lead oxide on the fibers of the SC. Oxidation of lead acetate or nitrate with calcium or sodium hypochlorite in an aqueous suspension of SC at a temperature of 60 ÷ 80 ° С - - 3. Gulf of water Optional Fak-no Fak-no 4. Enter SC, min 1-3 1-3 1-3 5. Stirring, min, not less 5 5 5 6. Input technological additives, min. 0.5-1.0 0.5-1.0 0.5-1.0 7. Stirring, min, not less 5 5 5 8. Input of combustion catalysts, min. - 0.5-1.0 0.5-1.0 9. Stirring, min, not less - 5 5 10. Input stabilizer combustion, min 0.5-1.0 0.5-1.0 0.5-1.0 11. Stirring, min, not less 5 5 5 12. The input of crystalline explosives, min. 0.5-1.0 0.5-1.0 0.5-1.0 13. Stirring, min, not less 5 5 5 14. Entering technical carbon, min. 0.5-1.0 0.5-1.0 0.5-1.0

Table continuation Name of operations Production Modes Prototype according to patent RU 2167137 According to the proposed technical solution Experience.I Experience. II 15. Stirring, min, not less 5 5 5 16. Entering a mixture of plasticizers with a stabilizer chemical resistance, min. 20-25 20-25 20-25 17. Stirring, min, not less thirty thirty 15-30 18. Enter 0.5-1% PAA solution, min. - 0.5-1.0 0.5-1.0 19. Stirring, min, not less 10 thirty 10 thirty The amount of introduced polyacrylamide in% by weight of fuel - 0.01 0.01 0.5 0.5 The total amount of solid additives introduced into the fuel,%, 10,2 8.4 8.4 29.0 29.0 The total amount of solid additives in the fuel by analysis,%, 8.2 8.3 8.3 28,4 28.3 Loss of solid additives,% 19.6 1,2 1,2 2.1 2,4 Note: 1. Prototypes were prepared in a reactor with a volume of 14 dm ³ , mixing module (fuel: water) = 1: 7. Mixing temperature 25 ° C. The weight of the prototype is 1.5 kg.
2. Used powdered PAA brand Praestol-2510.

Claims (2)

1. A method of manufacturing gunpowder and ballistic type fuel, including introducing into the digester and mixing in an aqueous medium components - nitrocellulose fibers, processing aids, combustion modifiers, plasticizers and stabilizers of chemical resistance to obtain a fuel mass, characterized in that when mixing the fuel components after introducing plasticizers uniformly injected with a 0.5 ... 1.0% aqueous solution of polyacrylamide, after which they are mixed for at least 10 minutes, then the fuel mass is pressed, rolled and pressing fuel blanks. 2. The method according to claim 1, characterized in that they use an aqueous solution of polyacrylamide, prepared preferably from powdered polyacrylamide.