Building a picture of components in urban dust in communities near ports, mines and rail corridors is providing valuable data to government and industry so that they can better inform communities about air pollution. It’s one of many initiatives that award-winning image analysis research is driving across the value chain. TONY HESELEV reports
Award-winning research is demonstrating how every picture tells a story, and how these pictures can open up opportunities from steelmaking through to environmental protection.
The research is making detailed images and data available to clients through an optical reflected light microscopy imaging system, known as Component Grain Analysis (CGA).
This system collects about 1000 to 2000 calibrated high-resolution colour images of a sample to produce a mosaiced image that is then processed with software. Size and composition information obtained for every particle can be displayed via the cloud.
Assessing urban dust for coal particles
For the past five years, the technology has been increasingly used to assess coal and other components of urban dust in communities near ports, mines and rail corridors.
The purpose of these studies was to identify whether the source of urban dust was mining, farming or other activities. This information can help government and industry establish environmental practices and policies to protect communities from air pollution.
Such information requires accurate and consistent characterisation of the amount, composition and size distribution of dust particles. The particle size information is important because a dust particle greater than 10 microns is classified as nuisance dust and those less than 10 microns are classified as respirable dust that can enter the lungs, which has important health implications.
Detailed analysis for multiple stakeholders
The key to the research is that it provides an unprecedented level of detail that stakeholders in government, industry and communities can see, use and analyse online.
“Our method is one of the only ones that can distinguish the carbon-based particulates in dust samples,” CSIRO coal petrographer and environmental scientist, Karryn Warren, explains.
The samples the researchers have used come from paper towelling, wipes from windowsills and patios, sweepings, and from high volume air samplers. Analysis of these samples can identify sources of dust to help clients understand where best to apply dust control methods – such as suppression using water and/or chemicals.
A key area of focus is on analysing environmental samples, such as sediments, tailings and urban dust, which can contain coal dust especially near railways and ports that transport coal. For example, around Newcastle, where many industries are located and from where about 150 million tonnes of coal a year is transported, the researchers used the CGA system to analyse samples and quantify and distinguish coal dust from other fine particles such as diesel and rubber from road transportation, paints and plastics from nearby industry, and organic matter including pollen and grass clippings.
The researchers also used the system on soil and sediment samples collected around ports and tailings dams, for example after a heavy rain event, to analyse whether any material has been washed out.
Beyond assessing urban dust, the technology was initially developed and used for resource evaluation studies and to better understand the utilisation behaviour of different coals. For example, miners have reduced exploration costs by using the research as a basis for industry-funded studies. Other studies have also helped optimise the recovery of fine coal during flotation and a particular coal’s suitability for any utilisation process such as coke-making (metallurgical coal) or power generation (thermal coal).
The technology is also being utilised by coal users, such as steelmakers, for assessing coals used in blast furnaces to make coke. Depending on the required end use, this enables steelmakers to better understand the attributes of individual coals and to use this information to construct coal blends at the highest quality for the lowest price in order to maximise returns.
Award winning R&D
The Australian Coal Association Research Program (ACARP) recognised the importance of this technology by presenting CSIRO’s project team, and process engineering specialist Dr Bruce Atkinson of Basacon, with an industry excellence award in 2018.
The awarded project team included Ms Warren, chemist and coal technologist Graham O’Brien and coal petrographer and mineralogist Priyanthi Hapugoda. CSIRO software engineers Peter Dean, Gregoire Krahenbuhl and Paul McPhee and imaging expert Dr Matthew Thurley of Innovative Machine Vision, were integral to the development of the CGA software.
“This work has made a step change in how industry utilises data and we see [the] work continuing to be taken up by our industry and its expansion internationally,” ACARP acknowledged.
The research has proved particularly important for mines, coal users (such as overseas steelmakers), ports, environmental companies and government departments.
The CGA system has been licensed to ALS, a global laboratory services company headquartered in Brisbane, Australia that undertakes routine analyses for mining companies.
Commercial arrangements have also been entered into with a Japanese steelmaker and with two other smaller companies, one in Australia and the other in Europe.