Demountable concentric nebulizer

Figure 7.33 (a) The components of a liquid sample introduction system for ICP glass concentric nebulizer, demountable three piece quartz torch, torch body, and glass cyclonic spray chamber, (b) The components assembled for use. This torch design is typical of that used in Jobin Yvon ICP instruments. [Courtesy of Glass Expansion Pty, Ltd., Australia (www.GEICP.com).]... 

The plasma torch consists of three concentric tubes, which are normally made from quartz. In Figure 4.2, these are shown as the outer tube, middle tube, and sample injector. The torch can either be one piece, in which all three tubes are connected, or it can employ a demountable design in which the tubes and the sample injector are separate. The gas (usually argon) that is used to form the plasma (plasma gas) is passed between the outer and middle tubes at a flow rate of 12-17 Lfinin. A second gas flow (auxiliary gas) passes between the middle tube and the sample injector at 1 L/min and is used to change the position of the base of the plasma relative to the tube and the injector. A third gas flow (nebulizer gas), also at -1 L/min, brings the sample, in the form of a fine-droplet aerosol, from the sample introduction system... 

ICP-OES The main consumable supplies in ICP-OES are in the plasma torch and in the sample introduction area. The major consumable is the torch itself, which consists of two concentric quartz tubes and a sample injector either made of quartz or some ceramic material. In addition, a quartz bonnet normally protects the torch from the RF coil. There are many different demountable torch designs available, but they all cost about 600-700 for a complete system. Depending on sample workload and matrices being analyzed, it is normal to go through a torch every 4 months. In addition to the torch, other parts that need to be replaced or at least need to have spares include the nebulizer, spray chamber, and sample capillary and pump tubing. When all these items are added together, the annual cost of consumables for ICP-OES is on the order of 3000-3200. (Note For this exercise, we will not include the cost of a power amplifier [PA] tube, which had a lifetime of approximately 1 year in older-style RF generators.)... 

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