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June 2016 www.coalage.com 41 fine coal recovery continued provement may be the difference between losing ground and making money in to- day's ultra-tight market. Additionally, the tonnage reporting to the thickener decreased and the ash content of the thickener underflow solids increased notably. The amount of chemi- cal required in the thickener decreased by more than 25%. The thickener operation and clarity improved with the removal of fine floatable coal from the thickener feed. Removing the recirculating load of fine clean coal improved plant recovery, im- proved the thickener operation, improved chemical usage and improved the clarified water quality. It also decreased the total tonnage going to the impoundment and increased the life of the impoundment. Looking Forward A large number of companies are strug- gling with the current dismal state of the coal market. The new market conditions push operators to find new ways to lower total cost. However, there is a breakaway point in slashing cost, which makes the en- tire operation less profitable. Another ap- proach, assuming that overall mining and processing costs allow, is to increase mine profits through improved process efficien- cy and increased yield. As shown above, SCI proved that some current coal losses can be changed into additional recovery in a profitable way. In-plant installation of the Sub325 sys- tem is scheduled for 2016 at two Northern Appalachia plant sites and two additional sites are anticipated. Conclusions More than 39 on-site trials of the SCI Sub325 Fine Coal Recovery System have demonstrated several points: • Considering the recirculation of clean coal, the typical plant flow sheet un- derstates the tonnage of coal in the screen drain by a factor of two or more. • Many of the test results to date indicate that less than half of the TOTAL screen drain tonnage going into recirculation is effectively recovered to product. • Solid bowl centrifuges, used worldwide for cost effective fine particle recovery, have been successfully customized for recovery and dewatering of fine coal. • When the screen drain material is pro- cessed through the SCI Sub325 unit, the recovery can be expected to range from 93% to 99% based on full-scale onsite testing to date. Thus, fine coal circuits can be off-loaded, which in turn pro- motes greater fine circuit efficiency and, hence, total plant efficiency. Acknowledgements The authors would like to thank the management of Coal Prep and Somerset Coal International management. They also want to acknowledge the many op- erations that contributed to the refer- enced testing and for allowing data to be anonymously included. It could not have been done without their cooperation and assistance. This article is adapted from a paper presented at this year's Coal Prep show held in Louisville, Kentucky, in April. 120 South Main St, Richfield, UT 84701 800-825-9674 • www.classicmo.com/j8.htm mining@classicmo.com The Jeep ® J8 meets underground mining requirements, cuts downtime and improves the bottom line. • Powered by a MSHA-approved VM Motori 2.8L Turbo Diesel • Base J8 chassis available in either two-or four-door configurations • Flatbed or pickup style vehicles are available with customizable wheelbases based on customer specifications • The only underground utility vehicle manufactured and supported by a major international company, Jeep ® ! Visit online or call today to find out more about the Jeep ® J8. Tough, Reliable and Economical. The Jeep ® J8 combines everything you need in one rugged, servicable package.