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online analysis continued tion, especially in today���s highly competitive market, to warrant an online analyzer to monitor and respond to real-time trends. This mine has two adjacent truck dumps from where the coal is transported directly to the four loadout silos by a 60-inch conveyor at rates of 3,000 to 6,000 tph. A two-stage sweep-arm sampling system is installed on this belt to determine the coal quality entering the silos. Physical samples are taken every three to four hours and subjected to both quick and ASTM analyses. The quick analysis results (sulfur, ash, moisture and Btu/lb) are available approximately three hours later. The ASTM results arrive up to 24 hours after the sample was taken. For the mine to respond to even the quick analysis, it is reacting to data that is on average almost five hours old. The need for online analysis was clear. Not only could a coal analyzer provide prompt coal quality data to pit operations for corrective action, it could also give the control room operator advance warning of impending problems in satisfying the contract specs of an upcoming train. Moreover, not only was the quick lab analysis not really all that quick, it also failed to include an analysis of the Na 2O fraction in the ash, itself a criterion for rejecting a train. A New Solution The new online analyzer that this mine decided to test could not only detect the low levels of Na2O that other online analysis technologies cannot, but it could also measure moisture directly, without having to make any assumption of bound moisture levels, as microwave moisture meters must. The analyzer itself operates on a sample stream; hence, the logical location for the unit was in the vicinity of the existing sampling system, where a sample could be routed to the analyzer. (See Figure 2). There are actually two technologies deployed in the Progression Titan CCA: Magnetic Resonance (MR) and Laser Induced Breakdown Spectroscopy (LIBS). MR has always held promise for online moisture measurement; the challenge was designing an analyzer that could incorporate an analysis chamber small enough for MR to operate. The Titan CCA does just that with its 1.2-inch diameter analysis chamber. The use of LIBS for online elemental analysis wasn���t entirely new, with an Israeli company having done trials in South Africa a few years ago without comFebruary 2013 Figure 4: Block diagram of the Titan CCA. mercial success. The Titan CCA���s LIBS analysis, in contrast, has shown excellent ability to do elemental analysis. Magnetic Resonance operates by the rapid application and removal of Radio Frequency (RF) electrical pulses within a magnetic field. The technology is equivalent to receiving a full body MRI at a hospital���the difference being the analyzer returns spectroscopy data while the hospital MRI returns images. This phenomenon provides precise hydrogen proton measurements leading to very accurate moisture measurement and hydrogen proton inputs into the calorific value determination. LIBS operates by focusing a laser into a second analysis chamber and analyzing the spectrum of the vaporized material (See Figure 3). Figure 5: Titan CCA���PRB installation. (Photo: Amy Donle) Not only can LIBS achieve accuracies comparable to those of other elemental analysis technologies (primarily PGNAA) for sulfur and the six major ash constituents (Si, Al, Fe, Ca, K and Ti), but it also can measure Na and Mg, which PGNAA cannot in most coals. This in turn leads to better ash fusion determination and more accurate base-to-acid ratio estimation. Progression is anything but a novice to these technologies. They have been successfully supplying the petrochemical market with MR technology for more than 20 years. In 2004, the company began working with some of the world���s most knowledgeable LIBS experts in the fields of space exploration, mining and Figure 6a: Titan CCA moisture performance. www.coalage.com 31