CS265489B1 - Process for drying granular explosives - Google Patents

Abstract

The solution relates to the drying of granular explosives. The drying takes place in a fluidized bed, where the ratio between the layer of loose granular explosives and the layer of fluidized granular explosives is 1.05 to 1.5. This achieves the interruption of the continuous contact between the granules and the conditions under which the extinction of fire or detonation occurs, and thus also a significant increase in the safety of the drying process.

Description

The invention solves a method of drying granulated explosives with a significant increase in work safety in this technological operation.

Existing methods of drying explosives are generally considered to be a very dangerous operation, as evidenced by a number of drying accidents. Solid granulated explosives are usually dried in chamber hot-air or vacuum dryers where the layer is stratified on sheets. Heating is carried out by flowing warm air or the hazelnuts are heated by a hot water system.

Less frequently used are dryers with mechanical agitation of the dried explosive, which are more economical, but mechanical agitation is a dangerous operation. According to another method, the dried layer is in aeration containers or nuci, which may be stationary or mobile. The preheated air penetrates at a low speed through a layer of explosive in which the particles are in contact with each other. Depending on the design of the system, air flows from top to bottom or bottom to top, the circuit being either pressurized or vacuum.

All of the above-mentioned drying methods are characterized by concentrating a significant amount of explosive in bulk concentration, corresponding to bulk density under given conditions, the individual granules touching each other, which results in a fire or detonation arising in one place spreading to the whole amount of explosive with catastrophic consequences .

The height of the granular explosive layer is always supercritical under bulk density conditions, i.e. it is higher than the minimum at which the detonation ceases. The subcritical layer thickness of high explosives is usually only a few millimeters, sometimes only a few tenths of a millimeter.

The above drawbacks are overcome by the method of drying granular explosives according to the invention, characterized in that the drying of the granular explosives takes place in a fluidized bed, wherein the ratio of free-flowing granular explosives and fluidized granular explosives is 1.05 to 1.5.

Fludizing the granulated explosive in said ratio will interrupt the continuous contact between the granules and the drying gaseous medium, creating a barrier to spread detonation. Drying is performed in a shallow, evenly organized layer that is constantly renewed, fluldizing to maintain the system under subcritical conditions for the propagation of fire or detonation, thereby achieving conditions in which fire or detonation ceases.

Example

The drying of the granular high explosive is carried out in an organized rotating fluidized bed in a fluidized bed dryer. A granulated explosive of 80 kg is introduced into the fluidizer, the extruder layer velocity is 0.8 ms ^{- 4} and the inlet air temperature is 65 ° C. The process air enters the fluidizer obliquely and moves an approximately 10 cm thick layer of granular explosive into motion, so that a low, constantly renewing layer is formed in the circulation movement above the disk grate, the volume of which is 1.1 times the free-flowing layer. Under these conditions, the fluidized layer is insensitive to ignition or detonation, which ceases under these conditions.

Claims (1)

object of the invention A method for drying granulated explosives, characterized in that the drying of granulated explosives takes place in a fluidized bed, wherein the ratio between the bulk bulk granular explosives layer and the fluidized granulated explosives layer is 1.05 to 1.5.