ACARP ACARP ACARP ACARP
Open Cut

Characterising and Assessing Fine Particle Concentrations in the Hunter Valley - Implications of National Environment Protection Measures for the Coal Mining Industry

Open Cut » Environment

Published: September 07Project Number: C13036

Get ReportAuthor: Peter Nelson, Anthony Morrison, Brendan Halliburton, Robert Rowland, John Carras, David Cohen, Eduard Stelcer | Macquarie University, ANSTO, CSIRO Energy Technology, CCSD

Particle, or dust, emissions from open cut coal mining have been the subject of significant investigation over a number of years. Previous ACARP projects investigated the issues surrounding particle emissions from coal mining in the Hunter Valley (Holmes Air Sciences 1999; Richardson 1999; Bridgman et al. 2002; Richardson 2002). The most recent of these, ACARP project C13036, investigated the use of optical samplers and used meteorological data to provide information on the likely origin of particles observed in the PM10 and PM2.5 size components. However, with the increasing focus on the human health impacts of atmospheric fine particles, and the suggestion that the finest particles may be more significant for human health impacts, the current project has focused on providing data on PM1 composition for the Hunter Valley.

The objectives of the current were:

  • extend the measurement program from C13036 for a further 12 months to provide a more robust set of PM10 and PM2.5 data for source determination;
  • obtain detailed PM1 chemical composition and SEM/TEM determination of size and composition of particles within the PM1 fraction in order to provide guidance as to their likely sources;

The major findings from the project include:

OSIRIS and TEOM measurements:

  • Further data were obtained with which to correlate the optically based instrument the OSIRIS with a TEOM for PM2.5. The results showed a variation in the correlation for the Singleton site compared with the data from Nelson et al.,(2007) , but showed reasonable agreement with the results for Glenville. As indicated in Project C13036 further work is required to determine corrections factors to adjust TEOM, GRIMM and OSIRIS data with regard to the Reference Method, for the Hunter Valley.
  • The data showed that the annual NEPM PM2.5 advisory target of 8 µg/m3 is likely to have been exceeded at all sites during the three year time frame of this study. These results indicate the difficulties which may be encountered in  the Hunter Valley in achieving the annual PM2.5 target were it to be adopted in the future as a compliance guideline. However, these results need to be treated with some caution due to the lack of direct harmonisation between the OSIRIS results and the reference method.

PM1composition

Crustal Material

The PM1 samples collected and analysed for the major crustal elements Al and Si show two important features. These are;

  • The Al and Si concentrations are reduced in the PM1 component relative to the 1<PM<2.5 μm component showing that the contribution of crustal material decreases in the finer particle component
  • The Singleton data show lower concentrations of these two elements when compared with data from Glenville. The Glenville site is closer to mining operations.

The SEM data show that larger crustally derived particles have generally disappeared from the samples at the 0.56 μm cut-off.

Seasalt

The changes which occur when seasalt aerosols react were discussed in some detail in the previous ACARP project report ((Nelson et al. 2007).  The information in the earlier report was primarily based on the bulk chemical analyses of PM filters by multi-element ion beam analysis. The SEM studies in the current project have confirmed the size related Cl depletion of seasalt (NaCl) particles. As examples, in the 3-4 µm cubic seasalt crystals captured on the MOUDI stage 2, almost all have a stoichiometric Na:Cl atomic ratio of ~1:1. Conversely, those salt derived particulates captured on the finer impaction stages all show the effects of significant chlorine depletion and replacement by the (NO3)-ion.

Carbon

Two types of carbon commonly contribute to particle concentrations. These are elemental carbon and organic carbon. The sources of both types of carbon are generally combustion processes. In the Hunter Valley another potential source of carbon is from coal dust, however, as this is produced from mechanical attrition processes this source is likely to be insignificant in the PM1 component of fine particles. This is largely supported by the SEM observations which show little evidence of coal like particles in the smallest size fractions.

The PM1 samples subjected to EC and OC analysis generally shows a higher ratio of EC/OC at Singleton compared with Glenville and also show an increase in the ratio for the PM1 component compared with the 1<PM<2.5 µm component at Singleton. However, the limited data obtained from the current study make it difficult to draw broader conclusions

Secondary aerosol

Secondary aerosol in the atmosphere forms from chemical and physical processes involving species initially formed as gases reacting to form new species which can condense onto existing particles or form new ones. This is a very complex area of science with significant research over the past decade attempting to quantify the formation and significance of secondary aerosol.

Potential sources of precursors for secondary particle formation include both anthropogenic and biogenic sources. Evidence for secondary aerosol formation has come from the SEM data in the current study and suggests that the secondary aerosol (identified as soft aerosol in the current study) dominates the 0.56 µm cut-off stage and lower.

Bioaerosols

Bioaerosols are ubiquitous in the atmosphere and include pollens and spores, fungi, algae and fragments of other living matter (Matthias-Maser et al. 2000). A wide range of this biological detritus was observed on all MOUDI stages.  These ranged in size from material collected on the 18 µm MOUDI stage down to identifiable material at ~ 0.3 µm.  

Overall findings for Hunter Valley PM1

In broad terms the following comments can be made concerning the PM1 component of the airborne particle distribution in the Hunter Valley:

  • Particles contributing to the greater than PM1 component of airborne particles are more likely to arise from
  • mechanical attrition processes, whether natural (windblown) or anthropogenic (including mining, agriculture and road dust)
  • power generation
  • seasalt and its degraded products and  
  • bioaerosols
  • Particles contributing to the PM1 component also contain material from the above sources but increasingly become dominated by the products of combustion processes or direct gas to particle conversion processes that occur naturally in the atmosphere.

In the Hunter Valley direct sources of fine particles from combustion processes include motor vehicle exhaust (diesels in particular, which would include road transport and possibly a significant contribution from mine vehicles and machinery), domestic wood burning and bush fire smoke. While secondary particle formation will also be occurring, the importance of this source is still the subject of intense scientific investigation worldwide and beyond the scope of the current project. Nevertheless the current project has shown that, soft aerosols, believed to be the products of atmospheric chemical processes form the bulk of the ultra fine material.

Requests for this project report  will also receive a copy of  C15042.

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C27039True Triaxial Strength Of Coal Measure Rocks And Its Impact On Roadway Stability And Coal Burst Assessment

Rocks in the ground are subject to a range of stresses. The stresses...

C3063Underground Vehicle Design Standards And Statutory Implications

The Australian underground diesel vehicle fleet has evolved since di...

C3064Conveyor Belting And Lagging Shear Characteristics - Drive Drum Slip

The primary aim of this project was to investigate the relationsh...

Underground

Open Cut

Safety, productivity and the right to operate are priorities for open cut mine research.

Recently Completed Projects

C29021Assessing The Impact Of Consecutive Night Shifts On Night-Time Alertness, Daytime Sleep And Timing Of The Circadian System

In the Australian coal mining industry, most guidelines for managing...

C33037Quantifying Recharge To Groundwater Systems In The NSW Coalfields (Sydney, Gunnedah And Gloucester Basins)

The purpose of this project was to estimate the rate of diffuse rec...

C26029Geological Controls On Fluorine And Phosphorus In Bowen Basin Coals

Increasing global restrictions on fluorine in product coal prompted ...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C27064Dry Beneficiation Using FGX And X-Ray Sorters

Conventional dry processing methods engage a single beneficiation de...

C26010Multi-Sloped Screening Efficiency With Changing Strokes, Frequencies, Feed Solids And Feed Rates-Pilot Plant Study

Optimising multi-sloped screens is often described as an art and the...

C28059Impact Of Water Quality In Coal Handling And Preparations Plants

The objective of this project was to deliver a concise reference do...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Technical Market Support

Mine Site Greenhouse Gas Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C23052Novel Stone Dust Looping Process For Ventilation Air Methane Abatement

This multi‐phase project is concerned with the mitigation of m...

C27054Optimisation Of A Thermal Flow Reversal Reactor For Ventilation Air Methane Mitigation

Ventilation air methane (VAM) generally accounts for 50-85% of the t...

C28076Selective Absorption Of Methane By Ionic Liquids (SAMIL) - Phase 2 Demonstration In A Packed Bed Reactor

An alternative approach to high temperature oxidation of ventilation...

Mine Site Greenhouse Gas Mitigation

Low Emission Coal Use

Step-change technologies aimed at reducing greenhouse gas emissions.

Recently Completed Projects

C17060BGasification Of Australian Coals

Four Australian coals were trialled in the Siemens 5 MWth pilot scale ga...

C17060AOxyfuel Technology For Carbon Capture And Storage Critical Clean Coal Technology - Interim Support

The status of oxy-fuel technology for first-generation plant is indicate...

C18007Review Of Underground Coal Gasification

This report consists of a broad review of underground coal gasification,...

Low Emission Coal Use

Mining And The Community

The relationship between mines and the local community.

Recently Completed Projects

C16027Assessing Housing And Labour Market Impacts Of Mining Developments In Bowen Basin Communities

The focus of this ACARP-funded project has been to identify a number...

C22029Understanding And Managing Cumulative Impacts Of Coal Mining And Other Land Uses In Regions With Diversified Economies

The coal industry operates in the context of competing land-uses that sh...

C23016Approval And Planning Assessment Of Black Coal Mines In NSW And Qld: A Review Of Economic Assessment Techniques

This reports on issues surrounding economic assessment and analysis ...

Mining And The Community

NERDDC

National Energy Research,Development & Demonstration Council (NERDDC) reports - pre 1992.

Recently Completed Projects

1609-C1609Self Heating of Spoil Piles from Open Cut Coal Mines

Self Heating of Spoil Piles from Open Cut Coal Mines

1301-C1301Stress Control Methods for Optimised Development...

Stress Control Methods for Optimised Development and Extraction Operations

0033-C1356Commissioned Report: Australian Thermal Coals...

Commissioned Report: Australian Thermal Coals - An Industry Handbook

NERDDC