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A method of manufacturing a pyrotechnic time delay composition includes admixing together a solid oxidizer, a solid fuel and water to form an aqueous slurry. The slurry is transformed into droplets. The droplets are gas-dried to form particles comprising the oxidizer and the fuel, with the particles

A method of manufacturing a pyrotechnic time delay composition includes admixing together a solid oxidizer, a solid fuel and water to form an aqueous slurry. The slurry is transformed into droplets. The droplets are gas-dried to form particles comprising the oxidizer and the fuel, with the particles thus constituting a pyrotechnic delay composition.

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1. A method of manufacturing a slow-burning pyrotechnic time delay composition, wherein the method includes: admixing together, under high shear and in the absence of a sensitizing oxidizer, a solid oxidizer, a solid fuel and water to form an aqueous slurry;transforming the slurry into droplets; and

1. A method of manufacturing a slow-burning pyrotechnic time delay composition, wherein the method includes: admixing together, under high shear and in the absence of a sensitizing oxidizer, a solid oxidizer, a solid fuel and water to form an aqueous slurry;transforming the slurry into droplets; andgas-drying the droplets to form particles comprising the solid oxidizer and the fuel, with the particles thus constituting the pyrotechnic delay composition. 2. The method according to claim 1, wherein a surfactant is present during the admixing of the oxidizer, the fuel and the water to form the slurry. 3. The method according to claim 2, wherein the surfactant is a wetting agent, and is selected from the group consisting of an acrylic ester, a styrene polymer, and an acrylic copolymer. 4. The method according to claim 3, wherein the wetting agent comprises 0.25% to 4%, by mass, of the slurry. 5. The method according to claim 2, wherein the surfactant is a rheology modifier and is selected from the group consisting of polyethylene glycol, polyvinyl alcohol, polyvinyl pyrrolidone, carboxymethyl cellulose and powdered smectite clay. 6. The method according to claim 5, wherein the rheology modifier comprises 0.25% to 4%, by mass, of the slurry. 7. The method according claim 1, wherein the solid oxidizer is barium sulphate, and comprises 24%-54%, by mass, of the slurry. 8. The method according to claim 1, wherein the fuel is silicon, zinc and/or magnesium and comprises 5%-50% by mass, of the slurry. 9. The method according to claim 1, wherein the slurry comprises 40% to 80% water by mass. 10. The method according to claim 1, wherein transforming the slurry into droplets includes atomizing the slurry. 11. The method according to claim 10, which includes spray drying the slurry, thereby to achieve the atomization of the slurry into droplets and the gas-drying of the slurry droplets. 12. The method according to claim 11, wherein the atomization of the slurry includes pumping the slurry at a high pressure through an orifice in a nozzle into a heated gas stream. 13. The method according to claim 11, wherein the atomization of the slurry includes pumping the slurry at a low pressure through an orifice in a two fluid nozzle into a heated gas stream. 14. The method according to claim 11, wherein the atomization of the slurry includes allowing the slurry to impinge on a rotating disc in the presence of a heated gas stream whereby high-velocity centrifugal forces generated by the rotating disc are used to form droplets in the gas stream. 15. The method according to claim 11, wherein the gas stream is a heated gas stream so that the gas-drying of the slurry droplets is thus achieved through contact of the slurry droplets with the heated gas stream. 16. The method according to claim 11, wherein the gas stream is air, which is at a temperature of about 240° C. 17. The method according to claim 16, wherein the atomization of the slurry is effected in a chamber through which the air passes. 18. The method according to claim 16, wherein the water in the slurry droplets evaporates over a period of 1 to 40 seconds, forming more or less spherical particles having a moisture content of up to 1%, by mass. 19. The method according to claim 1, wherein the pyrotechnic time delay composition has a burning rate of about 210 ms/mm. 20. The method according to claim 1, wherein the gas-drying comprises gas-drying the droplets in heated air. 21. A method of manufacturing a pyrotechnic time delay composition, wherein the method includes: admixing together a solid oxidizer, a solid fuel and water, in the presence of a wetting agent selected from the group consisting of an acrylic ester, a styrene polymer, and an acrylic copolymer, thereby to form an aqueous slurry;transforming the slurry into droplets; andgas-drying the droplets to form particles comprising the oxidizer and the fuel, with the particles thus constituting a pyrotechnic delay composition. 22. The method according to claim 21, wherein the wetting agent comprises 0.25% to 4%, by mass, of the slurry.