Scientists of Novosibirsk State Technical University NETI have patented a technology for recycling waste of gunpowder and pyrotechnic compositions (PTC) using alkalis, phosphoric acid as well as ash and slag waste. The technology reduces the waste hazard class and enables refusing the unecological and unsafe method of disposal by incineration.
To date, Russian enterprises working with gunpowder and pyrotechnic compositions face the problem of the waste disposal. Defense industry companies and companies that produce fireworks are forced to dispose of these explosive and flammable waste in the most primitive way: the wastes are simply burned in a specially fenced area. However, very often such a disposal site is located within the city. Local residents complain about the noise and the smell of aerosols. In addition, this method of disposal is not possible in bad weather.
The development of Novosibirsk scientists turns waste pyrotechnics and powder-containing substances into less dangerous ones, regardless of the location of the enterprise and in all weather conditions.
"Our department has been actively developing ways to neutralize waste. We have proposed a fairly simple technology for the waste disposal of gunpowder and pyrotechnic compositions (PTC), that is processing with concentrated alkali at high temperature. The result is an alkaline mixture which is neutralized with a fairly harmless phosphoric acid. The resulting viscous product is then cured with ash and slag waste. This invention has been granted a patent and it is now being implemented at the Novosibirsk Cartridge Plant," said Viktor Alexandrov, Associate Professor, Department of Environmental Engineering NSTU NETI.
According to Alexandrov, what remains of the PTC after the patented treatment is also waste, but without flammable and explosive properties. Such waste is classified according to the fourth hazard class (low-hazard substances suitable for disposal in landfills).
"NSTU NETI has conducted all the stages of laboratory research and created a pilot unit for a single loading of 1 kg. The unit passed factory tests, and then we and the employees of the Novosibirsk Cartridge Factory refined the proposed technology and designed a five-kilogram capacity unit," said Alexandrov.
In addition to the Novosibirsk Cartridge Factory, several other Siberian enterprises have shown interest in the development. Importantly, the alkalis, phosphoric acid and ash and slag waste are not expensive materials, consequently, the method of PTC recycling is cost-effective.
Currently, the technology is designed to dispose of about a hundred kilograms of waste per year. However, there are enterprises in the country that produce a larger amount of PTC waste. Without changing the essence of the technology, the developers are ready to adapt it to larger volumes of recycling.