ACARP ACARP ACARP ACARP
Open Cut

In-Situ and Off-Belt Bulk Analysis for Calorific Value and Partial Elemental Composition of Coal

Open Cut » Coal Extraction

Published: February 99Project Number: C5011

Get ReportAuthor: Mihai Borsaru and Z Jecny | CSIRO Exploration & Mining

This project dealt with the development of new techniques to provide in-situ and off-belt bulk analysis of coal for: slagging index; density; ash content; direct estimates of silica (Si), alumina (Al) and iron content (Fe). The technique employed was prompt gamma neutron activation.

The general objectives of the project were:

  • To expand on the capabilities of the spectrometric neutron-gamma technique for predicting, in-situ, the slagging of coal, density, calorific value and chemical constituents of the coal ash such as Si, Al and Fe.
  • Investigate this technique for off-belt bulk analysis using a 4p geometry similar to that employed for borehole logging.

The work undertaken for this project was carried out at the CSIRO Exploration and Mining, Queensland Centre for Advanced Technologies Laboratory. The project consisted of two stages:

The first stage investigated the application of the neutron-gamma technique to borehole logging. The aim of this research was to extend the capabilities of this technique for the determination in boreholes of the slagging index of the coals, their chemical contents of Si and Al and their density. This technique had been developed previously for the identification of the coal seams and the determination of their ash and Fe content.

The second stage consisted of investigating the neutron-gamma technique for off belt bulk analysis of coal in a 4p geometry.

Borehole Logging

Callide Coalfields:

Logging data from fifteen cored exploration holes was available for the present work. Multiple regression analysis was used to test the accuracy of the neutron-gamma tool for the determination of ash and iron in coal, techniques already developed and used in the Australian coal industry.

The capability of the neutron-gamma tool for the determination of Si, Al, density and slagging index of coal was then thoroughly investigated.

Theodore Coals:

Eight cored holes were logged with the neutron-gamma tool. The core was analysed in the laboratory and the assays were made available to the CSIRO. CSIRO undertook a thorough analysis of the logging and laboratory data in order to enhance the capabilities of the neutron gamma technique for coal logging. Data analysis and interpretation was similar to the data interpretation carried out at Callide Coalfields.

Off-Belt Analysis

The neutron-gamma technique was tested for bulk sample analysis of coal. Fifteen bulk coal samples were prepared from samples taken from Callide Coalfields. The samples were thoroughly mixed and analysed for ash content and chemical composition of the ash. The samples were then placed in large tapered plastic drums which had a 4p geometry. This 4p geometry resembles borehole geometry. Neutron-gamma measurements were taken with the borehole logging tool that was used for logging the cored boreholes.

The 4p geometry chosen in this work is different from the geometries normally used in static bulk analysis or on-stream analysis. The 4p geometry is the most efficient geometry allowing the use of lower activity sources without decrease in counting statistics and accuracy. This geometry can also be adapted for off-belt on stream analysis.

Project Outcomes

The present work has extended the capabilities of the neutron-gamma technique for borehole logging of coal.

An important outcome is the development of the tool for the determination of density in boreholes. It is widely accepted that the backscattered gamma-gamma technique is 'the technique' for density measurements in boreholes and the gamma-gamma tool is always selected for density measurements. This work demonstrates that the neutron-gamma tool can also be used for density measurements. This development makes neutron-gamma a powerful technique for coal logging.

The work carried out under this grant demonstrates that the neutron-gamma technique is capable of predicting the deformation temperatures for coals for which a correlation exists between deformation temperature and the percentage of Al, Si and Fe present in coal. However this technique does not work in coal deposits where such correlations do not exist. In the present work, neutron-gamma successfully predicted the deformation temperature for Theodore Coals but failed to predict this temperature for the coal from the Callide Coalfields.

The neutron-gamma technique developed by the CSIRO for coal borehole logging has been commercialised and is available to the coal mining industry. By comparison to the commercial gamma-gamma technique that measures the density and ash content of coal, the neutron-gamma measures simultaneously the density, ash, Al, Si and Fe of coal. The deformation temperature can also be determined in boreholes in some coal deposits.

The present work also demonstrated that the neutron-gamma technique can be used for off-belt bulk analysis of coal in a borehole like 4>p geometry. This is a more efficient geometry than others employed for bulk analysis. The ash, Al, Si and Fe content of coal were determined with good accuracy.

 

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C25060Development Of Borehole Shear Monitoring Device For Routine Application In Coal Mine Roadways

This project outlines the development of a cost effective, routine s...

C26056Optimisation Of Low And High Pressure Longwall Hydraulic Systems

This project aimed to establish if longwalls with Hi-Set systems cou...

C27007Assessment Of Pyrite Coal Dust Induced Pneumoconiosis

There have been recent concerns regarding the re-identification of C...

Underground

Open Cut

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

Recently Completed Projects

C25031Developing Closure Criteria For River Diversions: An Alternative To Reference Sites

The use of reference sites for establishing closure criteria in area...

C25025Guidelines For Estimating Coal Measure Rock Mass Strength From Laboratory Properties - Report A Empirical Approach And Report B Synthetic Rock Mass Models

This report combined different approaches to investigate the estimat...

C27074Tyre Integrity Monitoring

Driving mine trucks with underinflated and overloaded tyres subjects...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C6046Optimising Coal Fragmentation For Improved Recovery

Uncontrolled fragmentation, in particular that resulting in the gene...

C25019Adaptation Of Coal Grain Analysis To Improve Flotation Yield Estimation

This project involved sampling of full-scale flotation circuits at ...

C27033Comprehensive Flotation Model Using CGA Particle Surface Composition

The aim of this project was to adapt existing particle based flotat...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Recently Completed Projects

C27036Improved Understanding Of Coke Quality Using 3D Immersive Visualisation And Statistical Characterisation Of Microstructure Properties

This project carried out an explorative study into the use of a 3D v...

C27047Combustion Characteristics Of Australian Export Thermal Coal Using Advanced Imaging Techniques

During pulverised fuel combustion, coal particles are rapidly pyroly...

C25045Assessment Of In Situ High Temperature Strength Of Cokes

The research for this project was undertaken in three stages.

S...

Technical Market Support

Mine Site Greenhouse Gas Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C26004CFD Modelling Of Reverse Thermal Oxidisers For VAM Abatement - CFD Modelling Of Fixed-Bed RTO Devices

The project is part of a larger multi‐phase program of study a...

C27058Technological Assessment Of A Recycle Reactor For VAM Abatement

Underground coal mining emits high volumes of methane, diluted in ve...

C27008Selective Absorption Of Methane By Ionic Liquids

The connection of a ventilation air methane (VAM) abatement plant di...

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