Space miners may need to go with the flow

It is no secret that over the last couple of decades, mining in Australia has increased to the point that it is a world-class provider of resources and the technologies to extract them. Fields once thought played out have been revived through a better understanding of mineral exploration and extraction.

One of the leading innovators in Australia is the University of Adelaide, which has consistently ranked in the top 1% of schools worldwide for academics, innovation, and research. What makes this Aussie university even more impressive is the fact that space agencies and exploration companies are turning to them to help transform Earth-based mining methods into extraterrestrial extraction technologies.

One such method that has been around for nearly seventy years and recently adapted to mining is a process called continuous-flow chemistry, also known as plug-flow chemistry or microchemistry. This process separates minerals at a microscopic level through careful control of heat, exposure time, and pressure.

Leaching has long been a known process for extracting certain metals and minerals, but the process has a history of being harmful to the environment, wasteful and dangerous to the worker. This process was made safer through batch process chemistry. The batch process, however, has one big shortcoming – it can often be a long process that focuses on the extraction of one commodity.

With continuous-flow chemistry, multiple extractions can be made from a single source when applying and adjusting the rate of flow, heat, and pressure to free up the desired mineral based on its chemical makeup. The process is ongoing as the microreactor is continuously being adjusted for the next extraction process and the elements needed in the process are being recycled back into the microreactor for the next round of extraction.

For example, gold has a melting point of 1,948 degrees Fahrenheit. Increase the pressure and you can reduce the amount of time it takes to reach the melting point. If your sample also has nickel, you simply adjust the temperature and pressure to reach its melting point of 2,651F. Each solution that you have run through the sample will contain the targeted metal that can be condensed back into a solid state.

Of course, this is an oversimplification of the process, but it is important to understand its potential in space mining. Rather than launching massive machinery, which is very costly, these microreactors can be assembled to do the process in a more cost-effective manner with a potentially reduced cost to launch into space.

It is also important to consider that many asteroids and other extraterrestrial bodies have not gone through the same magma and deep planet pressures that have separated and diffused minerals back into Earth's crust. So, oftentimes minerals found in space are microscopic and densely intermingled with others that you may not normally find together here on Earth because of our planet's geological processes.

Having a method like continuous-flow chemistry is expected to allow for maximized process of resources giving a greater return for the investor. Through innovation, the next generation of microreactors will hopefully use smaller amounts or resources to extract minerals and will be self-contained, lightweight processing plants.

As we edge closer to space exploration and habitation, simplifying and reducing the launch cost will be a large factor in determining the success of man's next steps into our solar system and beyond. Field leading schools like the University of Adelaide are tackling the challenges of the extraction processes of mining not only here on Earth now, but our future in space.