By Robin De Angelis

June 21, 2017 - A new building has joined the Big Nickel on the site of Dynamic Earth in Sudbury, Ont.

Engineer Dean Millar initially developed the Hydraulic Air Compressor (HAC) project as a proposal to find an innovative way to produce compressed air.

But then, with the help of a grant from the Northern Ontario Heritage Fund, Millar was able to build a demonstration facility.

Compressed air is a key resource for industries including mining, automotive, manufacturing and forestry.

"About 10 per cent of the electricity used in industry in any modern economy is used to compress...one gas or another," Millar said.

While air is generally compressed using electricity, the HAC system uses water and a smaller amount electricity.

According to Millar, water and air mix together in a tank at the top of the system. The water is pressurized as it travels down a vertical pipe, producing tiny bubbles of compressed air.

The compressed air is separated in a tank at the bottom of the system and is drawn out through a pipe. The water is then fed back into the system.

Mining Companies Could Use 13 Percent Less Electricity

In mining, compressed air is used for a variety of tasks, including pneumatic drilling, actuating chutes, cleaning out drill holes and providing emergency air to refuge stations.

Millar said that mining companies could use up to 13 per cent less electricity with hydraulic air compression, than with other methods.

"What we're trying to do is effectively lower the cost of energy for the mining companies, so that they can maintain their competitiveness on the global mining stage."

In addition to the lower cost, mining companies could also reduce their carbon footprint with a hydraulic air compressor.

"Somewhere like Alberta, relies on fossil fuels quite intensively to produce its electricity," Millar said. "If you can reduce electricity, you will save a great amount of carbon."

Millar is also interested in the prospect of using the compressor to dissolve harmful flue gases, like the smoke that comes from Sudbury's Superstack.

'We Might be Rewriting a Couple of Textbooks'

Millar said he is excited about the opportunity for scientific advancement. This could be the first example of a practical isothermal compressor.

An isothermal process is when there is a change in a system that occurs at a constant temperature. In the HAC system, Millar said the process of compressing air should occur at around the same temperature.

"If you read a textbook in thermodynamics, they say that it's an ideal process that cannot be achieved practically." he said. "So in other words, we might be rewriting a couple of textbooks."

The facility at Dynamic Earth is available to be used by companies and scientists looking to test products and conduct research.

"What we hope is that when people find out about the demonstrator facility and what it can do, that it will open the door for many additional areas of innovation and scientific development to take place here." 

The Hydraulic Air Compressor demonstrator was created by engineer Dean Millar, to find an innovative way to produce compressed air. A working model now operates outside Dynamic Earth in Sudbury, Ont.

Photo by Dean Millar

A 3D rendering of the Hydraulic Air Compressor. Water mixes with air at the top; the water is pressurized as it travels down a pipe, producing tiny bubbles of compressed air. The air is separated at the bottom and drawn out through a pipe.

Photo by Dean Millar

Water and air mix together in a tank at the top of the system, before being sent 25 meters down through a vertical pipe.

Photo by Dean Millar