ACARP ACARP ACARP ACARP
Technical Market Support

Australian Coal Quality Impact Model

Technical Market Support » Thermal Coal

Published: October 96Project Number: C3091

Get ReportAuthor: Ashley Conroy, Phil Bennett | ACIRL, Australian Combustion Technology Centre

This project examines the ability of CQIM (version 1.2) to predict the performance of Australian coals in some of the many processes that occur in a modern coal-fired power station.  The continued growth in the world thermal coal market is resulting in greater diversity in thermal coal suppliers. The operators of coal-fired power stations are looking at computer software to assist in the evaluation of the impact of coal properties on the operating and maintenance costs.

One such computer software is EPRI's Coal Quality Impact Model (CQIM) developed by Black & Veatch.  CQIM is a computer model designed to facilitate the prediction of performance and cost impacts of firing alternative coals at an existing or proposed power generating station.  This project examines the ability of CQIM (version 1.2) to predict the performance of Australian coals in some of the many processes that occur in a modern coal-fired power station. The processes examined in this project were limited to ones where full or pilot scale data was available for comparison.

 

Method

The processes that were examined in this project were:

  • milling
  • combustion
  • impact of ash
  • emissions
  • maintenance and availability of milling and ash handling plant

The full scale data used in this evaluation was supplied by Pacific Power, and pertained to equipment at Eraring Power Station.

Eraring Power Station operates four 660 MW IHI designed generating units. These units are single furnace, twin-drum type using natural circulation with a divided back pass and balanced draught. Each unit is fed by seven tube mills.

The pilot scale data was taken from the testing of 38 coals in ACIRL's 150kW pilot scale boiler simulation furnace. Eleven of the coals were blends.

The adjustment, based on one coal's performance, of the mill performance curves used by CQIM is a satisfactory approach to predict mill capacity for the coals being evaluated. CQIM does not attempt to predict the size distribution of the coal or mineral matter.

To determine the combustion performance of a coal, CQIM allows the user to select either a simple model or detailed model.

The simple unburned carbon model is based on empirical correlations. The detailed unburned carbon model uses estimates of the char kinetic parameters with a detailed determination of the time temperature history of the particle to estimate the unburned carbon loss.

CQIM's simple unburned carbon model gives a good estimate of the carbon burnout for a wide range of coals as shown by the comparison with pilot scale data. The detailed burnout model suffers from instability problems which could reduce its accuracy.

The use of indices, determined from the bulk ash properties, to predict slagging and fouling characteristics of a coal does not fully account for the impact of individual minerals or the influence of fluid dynamics. CQIM failed to predict the reduced heat absorption by the waterwall that was recorded during one of the tests at Eraring. This was due to the coal's unusually low ash absorptivity.

 

Results & Conclusions

The power of CQIM is its ability to relate coal quality to fuel costs, maintenance costs and the availability of a power station.

This ability of CQIM to model the large number of interacting processes that occur within a power station depends on the use of correlations relating these processes to coal properties.

CQIM reduces the possible errors in using empirical correlations by using the known performance of one coal to calibrate its predictions for other coals fired in the same power station.

This means the user has to be careful about the choice of the calibration coal, ensuring that this calibration coal is similar to the other coals that are to be evaluated, the completeness of its performance data.

With the improvements that are planned for future versions of CQIM, it is likely that its use by power station operators to evaluate potential coal supplies will increase. Australian producers should continue to evaluate future versions of CQIM.

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C21013Improving Cavity Prediction On Longwall Faces Through A Combination Of Reliable Convergence, Canopy Attitude And Leg Pressure Monitoring

Most Australian coal mines have shield leg pressure monitoring in real t...

C24014Distributed Acoustic Conveyor Monitoring

CRC Mining have investigated the application of fibre optic Distribu...

C25054Distributed Acoustic Conveyor Monitoring - Phase 2

This project is phase 2 of the distributed acoustic sensing project ...

Underground

Open Cut

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

Recently Completed Projects

C25035Coal Subsurface Mapping For Open Cut Selective Mining

A reliable coal seam sensing system is required to improve the produ...

C25038Dragline Excavation Sequencing

It has long been recognised that optimising the positioning and mate...

C26019Prediction Of Long Term Erosion At Pit Walls

The objective of this project was to provide a basis for estimating ...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C26007 Revised Dustiness And DEM Test Method (Update Of AS4156.6) Part 2:Preparation

In 2015 project C23054 investigated and reviewed the Australian Stan...

C22033Advanced Control And Optimisation Of DMC Operation

The objective of this project was to develop, implement and demonstr...

C24045Adaptation Of Coal Grain Analysis To Improve Flotation Yield Estimation

Yield estimation from resource data is notoriously difficult. Facto...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Recently Completed Projects

C25042Mechanistic Model Of Coke Development In A Coke Oven Situation

The standard approach to evaluate the potential of coals or blends t...

C25050Overview Of Outcomes Of Research Supported By ACARP And NERDDC On The Utilisation Of Coking Coals, 1978-2014

The Australian coal industry has funded a substantial body of work o...

C25046Using High Range Mass Spectrometry To Study The Link Between Coal Structure, Coke Strength And Thermoplastic Chemistry In Blends

This project investigated the use of Laser Desorption/Ionisation tim...

Technical Market Support

Mine Site Greenhouse Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C24061Proof-Of-Concept Photocatalytic Destruction Of Methane For Coal Mining Fugitive Emissions Abatement

Australia's fugitive emissions in 2015 were 41 Mt CO2-e (representin...

C23052Novel Stone Dust Looping Process For Ventilation Air Methane Abatement - Phase 3

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

C19054VAM Enrichment With A Two-Stage Adsorption Process

Treatment of ventilation air methane (VAM) with cost-effective technolog...

Mine Site Greenhouse 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