Wednesday, January 21, 2009

991 CEM - Continuous Emission Monitor

SO2 (sulfur dioxide) Continuous Emission Monitoring


so2 continuous emission monitoring

Continuous Emission Monitoring (CEM) Systems are mandatory on virtually all industry waste chimneys or stacks today. Depending on the industrial process and regulatory agency requirements, the CEM could be required to report the pollutant of interest on an oxygen (O2) free, dry basis or, on a mass basis (tons per day, pounds per hour). Galvanic Instrumentation Ltd. offers systems that comply with both requirements.

Instrumentation System

Because the O2 free basis system measures the pollutant on a dry basis, a sample dryer is incorporated in the sample system. The concentration of oxygen is also measured and the measured dry pollutant concentration is corrected to zero oxygen.

The mass emission system measures the pollutant concentration on an as-is (hot/wet) basis and incorporates gas stream velocity and temperature measurement devices. The volume flow rate of the effluent is determined along with the mass emission rate of the pollutant of interest.

Continuous Emission Monitoring

Galvanic’s CEM System features our ultraviolet (UV) fibre optic spectroscopy for the sulfur dioxide (SO2) analysis. Depending on the type of system specified, the analysis is performed on either a dry or hot/wet basis. For either one sample is transported from the sample point to the analyzer through a heated sample line (steam or electrical heating is available). The dry base system uses a chilled, water-condensing unit to remove the water from the stack gas sample.

The mass style of CEM system is complete with a velocity measuring device suitable for an accurate measurement of the gas velocity for a given chimney or stack. A variety of different measurement techniques and hardware devices (pitot tube, annubar, Kurz probe, etc.) are available and necessary since no one sensor is applicable for all ranges of velocities, temperatures, etc. Galvanic selects the appropriate device based on the engineering data for your application. The stack gas temperature measurement is achieved with a thermocouple selected and calibrated for your stack gas temperature range.

The stack gas volumetric flow rate is calculated by the system computer using the data from the velocity device, the gas temperature and other parameters including the stack diameter, specific gravity, profile factor, etc. The SO2 concentration and volume flow rate are combined and the mass emission rate for the SO2 is calculated and output in terms of either SO2 or sulfur. Outputs provided are the instantaneous values for SO2 concentration, volume flow rate and mass emission rate.

Tytronic Sentinel Amine Analyzer


APPLICATION

The Tytronics Sentinel Amine Analyzer is an online process analyzer that is capable of measuring acid gas loading in both rich and lean amines. It can be used to measure H2S content in amines (as sulphide), total acid gas loading (both CO2 and H2S), as well as amine strength. Multiple analyzers may be required depending on the number of analyte measurements, concentration range and distance between sampling points.

PRINCIPLE OF OPERATION

The Sentinel analyzer is a potentiometric titrator which uses an electrode to monitor changes in ion activity in the solution during the addition of a titrant, referred to as titration. An equivalence point or endpoint is reached when the ions in solution have completely reacted or complexed with the ions supplied through the titrant addition (there is no further ion activity). At the equivalence point the concentration and volume of the titrant solution added to the reaction cell determines the equivalent concentration corresponding to the analyte of interest.

It is this titration technique that is used to determine three main analytes of interest in the amine samples. These are as follows:

  1. Amine Strength Determination - To know the exact loading of the amine, it is necessary to know the amine strength, a measure of the percentage by weight of an amine solution that is amine. This measurement is carried out using a color titration of lean amine.

  2. Total Acid Gas Loading - The acid gas loading is determined by titration of the lean or loaded amine with a base, with the endpoint determined using pH measurement.

  3. H2S loading - H2S loading is determined by potentiometric titration of the lean or loaded amine using a sulphide selective ISE.

FEATURES AND BENEFITS

  • If one of each amine analyzer variant is installed, the analog outputs from each unit can be combined in a data collection system to get a complete set of measurements for each stream - amine strength, H2S concentration, and CO2 concentration.

  • Regenerate amine only when necessary based on loading, reducing energy costs for regeneration and extending amine life.

  • Calibration based on lab results - monthly laboratory measurements of the parameters of interest are used to calibrate the analyzer

  • Reduced regenerator steam consumption by operating with residual H2S that ensures specification sweet gas instead of over-stripping to provide a safety margin

  • Reduced amine loss through carry-over

  • Reduced plant corrosion

PLGC II Gas Chromatograph




For pipline and process applications

The PLGC II is a compact and low cost gas chromatograph equipped with a universal thermal conductivity detector. The unit offers a wide range of applications where hydrocarbon gas or fixed gas analysis is required, such as in BTU measurement for the natural gas industry.

The PLGC II is a fully automated system designed to perform on-line, real-time analysis. The Windows® based configuration software allows the user to view recent or saved chromatograms as well as configure the analyzer.

  • 24 volt DC operation (optional 110/220 VAC)

  • Division II electrical classification standard (Div I and Atex Zone II approved units are optional)

  • Thermistor TCD detector

  • No instrument air

  • Low helium consumption

  • Reliability

  • Low maintenance

  • Small, compact package

  • 15 minute or 5 minute cycle times available

Infra-Red CO2, CH4, and CO Analyzer


A Low Drift, High Accuracy Analyzer

Galvanic Applied Sciences Inc. now offers CO2, CH4 and CO measurement technology. The sensor is based on true dual wavelength infrared technology with no moving parts. The result is a low drift, high accuracy analyzer, with a fast response time and low power consumption.

  • Low cost

  • Accuracy

  • Ease of use

  • Reliability

  • Specific

Infrared Analyzer


INFRARED ANALYZER

The above diagram provides a graphic representation of the basic design of an infrared analyzer which is used to measure breath alcohol concentrations. The design is based on the fact that specific wavelengths of infrared energy are absorbed by ethyl alcohol molecules. In its simplest form, the instrument's detector measures the change in the amount of a specific wavelength of infrared energy that passes from the infrared source (lamp), through the sample chamber and filter wheel to the detector. The change in response on the detector, as a breath sample is submitted to the sample chamber , is monitored and analyzed by a processor in the instrument. The change in the signal is used to calculate an alcohol concentration

The difference between the amount of infrared energy that reaches the detector when the sample chamber is free of compounds that absorb the infrared energy and the amount of infrared energy that reaches the detector when a subject's breath sample is within the sample chamber, provides an indication of the concentration of the absorbing substances in the sample . If ethanol was the only molecule found in a breath sample that would absorb energy at the wavelength being recorded by the detector, the calculated difference in infrared energy reaching the detector could be used by itself to establish the concentration of alcohol in the breath sample. Unfortunately this is not always the case.

In order to deal with the lack of specificity, it is important that the primary wavelength of infrared energy used to measure the concentration of alcohol is selected based upon its limited cross sensitivity to other substances that are commonly found in the human breath. The spinning filter wheel in the diagram above is used to modulate the light through several different filters allowing different wavelengths of infrared energy to be transmitted to the detector for analysis. The secondary wavelengths of energy are selected based upon the interfering compounds that could be found in a human breath sample. If these compounds are identified and are in concentrations that would adversely effect the calculated ethanol result, the analysis can be aborted.

One other important point is that the differing concentrations of alcohol or other energy absorbing compounds found in the subject's breath sample are not in a one to one relationship with the amount of energy that reaches the detector. In other words, a .050 alcohol concentration may absorb X units of infrared energy, but a .200 will not absorb 4X units of infrared energy. This inherent non-linearity can be overcome by performing a multi-point calibration. To ensure that the instrument is properly quantifying alcohol and the other substances, it would be prudent to perform multi-point accuracy checks for each substance of interest and ensure proper calibration over the entire range of substances and concentrations.

Finally, infrared systems require power to light the IR source, heat the sample chamber, power the light modulator and drive the detector and associated circuits. Historically, the signal from the detector has been small relative to the noise generated in the system. This has made it difficult to resolve changes in the signal when low level concentrations of alcohol are presented to the system. To solve this problem, several manufacturers have included cooled detectors. These systems require additional power, but the cooled detector decreases the noise on the detector and enhances the instrument's performance at the low alcohol