RECYCLING OF EMULSION EXPLOSIVES: A FUTURE-FOCUSED INITIATIVE

At FORCIT, we are committed to reducing the environmental impact of our operations. We continuously explore new raw materials and operating methods with a low carbon footprint. One such initiative involves studying the chemical decomposition of emulsion explosives and the potential reuse of the resulting fractions, either within our own production or as secondary material streams.

Traditionally, unusable emulsion has been disposed of through incineration. Recycling this material is extremely challenging due to safety concerns. Impurities in the emulsion can compromise quality or, in the worst-case scenario, lead to an explosion.

“Incineration is a safe method, but it still comes with inherent risks. Open burning of emulsion places a burden on the environment and requires auxiliary fuel,” says Laura Pitkäjärvi, QA Development Manager at FORCIT.

Chemical decomposition as a recycling method

“In 2022, we launched a project in collaboration with VTT Technical Research Centre of Finland to identify an optimal method for decomposing and separating emulsion explosives, as well as for processing the recovered ammonium nitrate to meet quality standards. Our aim is to recycle the resulting solution back into FORCIT’S production,” Pitkäjärvi explains. The project began with decomposition of clean emulsion classified as oxidizing (5.1). Following a successful pilot phase in 2024, FORCIT expanded its research to include the decomposition of explosive-classified emulsion (1.1).

Scaling the process to meet industrial needs

Most of the emulsion waste consists of explosive-grade material. This waste originates in FORCIT’S own processes. We also accept expired explosives for safety reasons. Some of FORCIT’s explosive waste is disposed of in Sweden or Norway at licensed disposal facilities.

“Incineration is not an especially environmentally friendly method. Particle emissions are generated, and nitrogen oxides are released, and the energy released in the process cannot be recovered, but currently, open burning is the recommended method of disposal due to safety concerns. As such, it is necessary and may never be entirely eliminated.” Pitkäjärvi notes. “Our laboratory-scale tests have shown promising results for chemical decomposition. That said, scaling up to a full industrial process still requires significant development. The future is still open, but I believe we will reach our goal,” Pitkäjärvi concludes.

HOW ARE EXPLOSIVES BURNED?

Emulsion explosives are incinerated through open burning. A burn site is prepared with hardwood logs, and and waste emulsion is added at a time. The pile is ignited using a remote control. The combustion process takes few hours, meaning the emulsion burns relatively slowly. Returned waste from customer site is always pre-sorted before arriving our site to minimize unnecessary risks.