Abstract: The disclosed invention relates to a calibration method, system and apparatus for a multimetals continuous emissions monitor system (hereinafter “multimetals CEMS”). More specifically, this invention relates to a calibration scheme for continuous monitoring of mercury emissions from stationary sources by plasma emission spectrometry. A source of mercury vapor, preferably a mercury permeation tube, entrains mercury vapor into a constant flow of carrier air. The carrier air mixes with a constant flow of diluent air in an aerosol mixer. The mixer is operably coupled to the analyzer. A gaseous mixture having a calibration mercury concentration flows from the mixer into the analyzer at a constant rate. A graph having coordinates of analyzer signal intensity and mercury concentration is used to plot the calibration scheme. A first signal intensity generated by the analyzer in response to the calibration mercury concentration is used for the first plot on the graph.

Abstract: The disclosed invention relates to a calibration method, system and apparatus for a multimetals continuous emissions monitor system (hereinafter “multimetals CEMS”). More specifically, this invention relates to a calibration scheme for continuous monitoring of mercury emissions from stationary sources by plasma emission spectrometry. A source of mercury vapor, preferably a mercury permeation tube, entrains mercury vapor into a constant flow of carrier air. The carrier air mixes with a constant flow of diluent air in an aerosol mixer. The mixer is operably coupled to the analyzer. A gaseous mixture having a calibration mercury concentration flows from the mixer into the analyzer at a constant rate. A graph having coordinates of analyzer signal intensity and mercury concentration is used to plot the calibration scheme. A first signal intensity generated by the analyzer in response to the calibration mercury concentration is used for the first plot on the graph.

Abstract: A convenient apparatus and method for inserting surrogate metal-entraining aerosols into exhaust stacks for the purpose of realistic dynamic testing of an emissions monitor. The aerosols contain elements required to be detected by the monitor. The 14 metals regulated by the EPA as hazardous air pollutants are of particular interest. The method requires less time and fewer skilled technicians than conventional testing methods. In a preferred embodiment of the present invention, a burner (e.g., propane or kerosene) is combined with a combustion chamber, a fan, an air compressor, at least one peristaltic pump, at least one surrogate reservoir, and the necessary ductwork for connection to an exhaust stack. The amount of surrogate aerosol to be introduced to the stack is adjusted at the peristaltic pump. After heating by the burner and subsequent introduction into the hot stack, the surrogate homogeneously mixes with the exhaust stream and is presented to the sensor as a dry gas component of the exhaust stream.

Abstract: Introduction of sample stream air into argon inductively coupled plasma permits continuous monitoring of hazardous air pollutant metals in combustion flue gases. In addition to entrained particulates, various molecular components of flue gas are in the plasma. These species, and reaction products thereof, such as CN species, also undergo excitation resulting in complex emission spectra of appreciable intensity. Serious spectral interference arises for several metal elements, from molecular emission bands associated with the stable CN radical, and other poly-atomic species, such as NO. Failure to account for these interferences can significantly degrade accuracy of monitoring particularly at low metal concentrations in the flue gas.

Abstract: A plasma torch for reliable analysis of airborne particulate matter permits real-time monitoring of airborne metal pollutants in flue gases from furnaces and incinerators. The torch injects sample air into argon plasma and has an outer tube to confine plasma gas for generating a plasma fireball. An intermediate tube has an outwardly flared portion concentrically disposed within the outer tube to form an outer annulus for feeding plasma gas to the fireball. The intermediate tube also has an injector sheath tube joined at its base to the base of the flared portion and concentrically disposed within the flared portion. The injector sheath tube is parallel to the outer tube. An inner capillary injector tube injects sample air into the plasma fireball.

Abstract: Sampling interfaces and methods of operation thereof having increased duty cycles and pressure equalizations that improve sensing of airborne metals in air samples fed to a continuous emissions monitor. Residual pressure in one or two sample reservoirs (loops) can be automatically equalized just prior to pneumatic connection between each sample reservoir loop and plasma in a plasma torch, thus minimizing or eliminating perturbation of the plasma. Deliberate sequential activation of valves allows each sample reservoir loop to be first isolated from the vacuum pump, and then momentarily as its pressure is equalized, it remains isolated from the plasma as well. Finally, pneumatic connection is made between each sample reservoir loop and the plasma allowing the contents of each sample reservoir (now at the same pressure as the plasma) to be transported into the plasma.

Abstract: A portable apparatus for continuous real-time measurement of airborne met, comprising an isokinetic sampler, a sample line, a sampling interface device, a pump, and an inductively coupled plasma atomic emission spectrometry (ICP-AES). A method for measurement of airborne metals by use of such an apparatus is also described, in which the sampling interface device accommodates the high, continuous sample collection flow-rates necessary for isokinetic sampling while at the same time permits sample air to be introduced into the plasma at preferred moderate flow-rates. A method for field standardization of the ICP-AES is also described whereby a relationship between aqueous solutions of metals and their aerosol counterparts is established, thus later allowing the field use of the aqueous metal solutions to simulate a particular range of airborne metal concentrations.

Abstract: An isokinetic sampling system and method of operation assures the taking of more valid data over a long period by automated isokinetic sampling of flue gases in the stack for a stationary combustor. Sample air is extracted from the flue gases by a sampling probe having a sampling nozzle of a precise inner diameter, a thermocouple to measure the air temperature in the stack, and a pitot tube that gives readings representative of differential pressure across sampling nozzle. A separate transducer senses absolute pressure of the flue gases. Temperatures, absolute pressures and differential pressures of the flue gases are measured and representations of the temperatures, absolute pressures and differential pressures are fed to a micromanometer which feeds signals representative of these representations to a computer that generates responsive control signals for a mass flow controller.