Quantitative Analysis of Coal Fouling in the Stanwell Balloon Loop Final Year Project: Benjamin Chappell Academic Advisor: Jerome Egwurube – Central Queensland University Industry Advisor: Ryan Bell – Aurizon Contact Information: E: [email protected] M: 0456 707 111

Introduction Ballast is a rock aggregate that forms one of the main layers of the train structure. The voids present in the ballast provide drainage and lateral support to the track and allow for the load of the train to be dispersed over a large area. On the journey from mine to port, coal falls off the wagons and fills the voids in the ballast. As the voids become increasingly ‘fouled’, the ballast’s ability to drain and provide a stable foundation is reduced.

This ultimately becomes the root cause of a number of issues and formation failures (due to the poor drainage) hence leading to reactive maintenance efforts as opposed to preventative maintenance efforts from Aurizon. A preventative maintenance program would allow for increased productivity and capacity of the network as there would be less closures and speed restrictions due to coal fouling related issues.

Currently, ground penetrating radar (GPR) is used as a non-intrusive means to determine the extent and severity of ballast contamination. This project proposes a ‘rain gauge’ type device that is installed into track to enable quantification of external fouling sources in order to complement, validate and supplement GPR data and establish fouling rates.

Figure 1: Heat Map of fouling rates in Stanwell Balloon Loop Methodology 1 – Design, Approve and Construct the ‘rain gauge’ type containers for implementation into the track profile. 2 – Implement containers into pre-determined locations around the Stanwell Power Station Balloon Loop Results 3 – Analyze data to determine what locations have accelerated rates of fouling After installing, retrieving, weighing and drying the coal samples 4 – Compare fouling data gathered to existing fouling information collected in each container the data was then analyzed and 5 – Propose how the project can be further utilized and refined to aid Aurizon’s understanding of the track asset compared to draw the following conclusions: - Locations 1 and 2 fouled at a relatively high rate - The containers closer to the mainline track at location 1 and 2 (containers A and ) fouled at a higher rate than the containers furthest away (containers C and D) - Locations 3 and 4 (located before the unloader) experienced a small amount of fouling across the left, middle and right containers. - The fouling experienced in locations 5 and 6 were extremely high - On average, at locations 5 and 6 the container in the middle of the track consistently collected more contaminates than those on the ballast shoulders - Empty trains fouled at a much higher rate than loaded trains as Figure 2: Average coal weight collected by Location and Orientation locations 2, 5 and 6 collected much more coal than locations 1, 3 and 4.

Figure 3: Coal Fouling Raw Data Figure 4: Locations 3, 4, 5 and 6 Figure 5: Locations 1 and 2 Conclusion The following conclusions could be drawn based on the experimental data obtained: - Comparing data from locations 1 and 2 showed that the containers placed closest to mainline track fouled at a higher rate than the containers placed in the middle and far side of the sleeper bay. Demonstrating that trains travelling past Stanwell to the port are also contributing to fouling in this location and not solely the trains entering/departing the Balloon Loop. - The fouling experienced in locations 3 and 4 was exceptionally slow and consistent across the left, middle and right of the track profile. - It was expected that locations 3 and 4 experienced low fouling rates as that particular section of track is straight, has good track geometry, is not located near any points and only experiences loaded rail traffic. Suggesting that loaded trains do not contribute as much to the fouling experienced as empty trains. - Locations 5 and 6 fouled at an extremely high rate, highlighting that the unloading techniques of the wagons are responsible for a large majority of the fouling right after the unloader. - On average, a majority of the fouling experienced at locations 5 and 6 were in the middle container. This shows that the Kwik-Drop Doors underneath the wagons are leaking residual coal onto the track. - In this investigation, it was found that empty trains foul at a much higher rate than loaded trains, meaning that the coal unloading practices are contributing a significant amount to the fouling experienced across the network.

Figure 6: Container Layout at Location 5 Recommendations From the data that was gathered, the following recommendations were drawn: - Results suggest that the unloading practices of the coal wagons foul the track directly after the unloader at a high rate, therefore to further diagnose the source of fouling it would be beneficial to install the containers at the mine loader to determine if more fouling is experienced during the loading process or unloading process. - Implement the containers around other assets such as bridges, level crossings and different types of turnouts to determine where the coal is falling off the wagons at these fixed points. - Conduct a sieve analysis on the samples that have been collected to further diagnose the source of fouling from the wagons (leakage through doors, parasitic coal on sills, shear plates, and bogies of the wagon) as the particle sizes will help identify where the coal is falling from the wagon. Figure 7: Top View of Containers at Location 5