Advanced Technology Helps to Remove Toxic Metals from Wastewater at Canadian Coal Mine

Anglo American, one of the world's largest mining companies, has selected GE’s (USA) Advanced Biological Metals Removal Process (ABMet*) technology to remove nitrate and selenium from wastewater discharge at its Peace River Coal Trend Mine in Tumbler Ridge, British Columbia, Canada. The project will represent the first installation of ABMet in Canada.

The coal mine has been operating since 2006, and new regulations prompted Anglo American to build a new wastewater treatment plant to remove nitrate and selenium in the wastewater. Currently under construction, the new facility is turnkey, providing a flexible solution for heavy metal removal. By using GE’s ABMet technology, Anglo American will meet British Columbia’s stringent standards for selenium and nutrient discharge limits.

ABMet is a patented biological water treatment system that uses naturally occurring microbes to reduce the amounts of selenium and other metals that can escape in discharge waters from coal mines and power plants. GE’s ABMet process involves running wastewater through a biologically active filter, which is “seeded” with naturally occurring microbes that target selenium and other potentially toxic metals. While selenium is typically difficult to remove from wastewater, ABMet enables the metal to be captured and removed from the wastewater stream.

“Before selecting GE’s ABMet technology for our new wastewater treatment plant, we commissioned a pilot study and competitive tender with multiple vendors. Ultimately, GE presented a turnkey water treatment solution allowing us to achieve compliance with nitrate and selenium discharge limits,” said Brendan Crisp, specialist project engineer at Anglo American’s Peace River operations. “It also will be used as a demonstration plant to assess performance and develop the criteria for additional wastewater treatment plants at our operations.”

The new wastewater treatment plant has been designed to treat 24 L/s (380 gpm) of flow and to meet nitrate and selenium effluent targets. The targets will reduce nitrates from 85 mg/l to 3 mg/l and selenium from 130 µg/l to 5 µg/l. The system is designed to achieve these limits at water temperatures of 4.4 degrees Celsius (39.9 degrees Fahrenheit) and warmer without the need for any post treatment.

“We are committed to creating solutions for mine water discharge applications where the removal of key contaminants, such as selenium, nitrate, sulphate and heavy metals, is necessary to meet environmental regulations. Our ABMet technology is ideal for tough-to-treat water and is a perfect fit for Anglo American’s Peace River coal mine,” said Yuvbir Singh, general manager, engineered systems—water and process technologies for GE Power & Water.

GE worked in cooperation with Stantec for construction and engineering on the project. The wastewater treatment plant is expected to enter commercial operation in the summer of 2014.

ABMet is a proven, reliable way to remove elevated levels of selenium, nitrate and metals found in wastewater streams in many industrial, mining and utility applications, such as at coal-fired power plants. The simple, reliable and low-energy system can achieve up to 99 percent removal of selenium and can discharge treated effluent containing 5 parts-per-billion or less of selenium, depending on wastewater makeup. 

*Trademark of the General Electric Company; may be registered in one or more countries.