Coal and parting extraction in Turtle Creek project

This preliminary feasibility report examines the feasibility of fitting a scraper fleet to the TurtlenCreek project for coal and partings extraction while keeping the truck and shovel fleet fornoverburden removal. Some distinctive characteristics of this project are:b 58% of coal seams are thinner than 0.2 m and 50% of these are thinner than 0.1 m; Thenmaximum coal seam thickness is 1.65 m; andb The dipping angle of coal seams is between 8 and 15 degrees.Conventional truck and shovel fleet was selected in the previous mine plan but the project wasnnot profitable and has technical issues. Therefore this research project investigates a scrapernfleet for all coal seams and thin interburden (below 3 m) extraction while keeping a truck andnshovel fleet for overburden and thick partings (above 3 m) removal. This new fleet combinationnwas analysed both technically and financially and compared to previous mine plan.nThe project was completed with the aid of mine planning, scheduling and computer-aidedndesign software, desktop research and communication with professionals in industry.The dual-engine open bowl wheel tractor-scraper was chosen for its ability to work on steepnterrain and it was decided to load downslope. The scraper is better for reducing the dilutionnbecause of its high precision of bowl control. Large scrapers are better for long haul (~2 km)nand have a relatively high production rate. The advantage of small scrapers is better bowlncontrol (~0.1 m). If the haul distance exceed 2 km, the scraper will not be as cost efficient asntrucks. Therefore the scraper will only be applied to Stage 1 operation.nnNew mine plan has a cut-off working section thickness of 0.2 m. That means if a coal seam hasna thickness less than 0.2 m, this coal seam will be removed as waste. Also, if a parting has anthickness less than 0.2 m, it will join to the coal seams above and below to make one workingnsection.Three scenarios were analysed in the financial model which are:b CAT 637 (18.3 m3) scraper fleet;b CAT 657 (24.5 m3) scraper fleet; andb CAT 637 and 657 hybrid fleet.The unit costs of these cases were compared to each other and the existing mine plan. The cashnunit cost ($/bcm) of these three scenarios is marginally higher than the conventional truck andnshovel operation. However, it was found that the CAT 637 and 657 hybrid fleet gives the lowestncash cost FOR ($/prod. t) among these cases which is 2.8% lower than the existing mine plan.nThis is caused by the assumption of lower dilution for scraper operations.This primary feasibility study only analyses the scraper working individually. Further worknmay focus on scrapers working in tandem. The length of working face as well as the fill factornof the scraper needs to be further determined. The working mechanisms should be developednfor every coal seam and parting in detail.n