1、GASMET CEMS overview
FT-IR分析系統針對CEMS和過程監測特殊設計，它典型應用于測量 H2O, CO2, CO, N2O, NO, NO2, SO2, HCl, HF, NH3, CH4, C2H6, C3H8, C2H4. The GASMET CEMS can be easily configured for new set of gases. Measured components and calibration ranges can be changed according to application.
The GASMET CEMS is designed for on-line measurements of trace concentrations of pollutants in wet, corrosive gas streams. All parts of the GASMET CEMS can be heated up to 180 ºC. No dilution or water removal is needed. Thus GASMET CEMS measures always-representative sample gas and also difficult gases can be measured (NH3, HCl, HF, SO3....).
The GASMET CEMS consists of GASMET FTIR Gas Analyzer, GASMET industrial computer, and GASMET Sampling System. As an option the system can be equipped with GASMET Oxygen analyzer and/or total hydrocarbon analyzer (FID). All parts of the system are 19” rack mounted and are installed on pullout shelves. The GASMET CEMS includes all power connections and temperature controllers for heated lines and heated sample probe. The operation of the system is fully automatic and controlled by the Calcmet software. Additionally all functions of the GASMET CEMS can also be performed manually.
GASMET industrial computer and Calcmet application software control the CEMS. The measuring data can be transferred from the PC to the Control room with digital outputs (ModBus) or with analog outputs 4-20 mA. The alarms are transferred with relay contacts. The GASMET CEMS provides alarm functions such as Function alarm, Service alarm and System alarm. Function and service alarms are associated with the GASMET FTIR Gas Analyzer and with the Calcmet analysis software. A system alarm comes from GASMET Sampling System and it includes temperature alarms (from sample probe, heated lines, sampling unit), flow alarm and pressure alarm for zero gas (option). If any of the critical alarms is activated, the instrument air or nitrogen (N2) starts to flow automatically into the sample cell to prevent condensation in the sample cell.
GASMET CEMS can be air conditioned by a Vortex cooling system or with a compressor-cooling unit. Vortex cooling is recommended in dusty ambient conditions. Vortex cooling requires compressed air.
Additional features of the GASMET CEMS include multipoint sampling for two sample points, span gas inlets for calibration gases, or back flush operation. GASMET CEMS is also supported by full remote control.
In the following figures the different components of the GASMET CEMS system are displayed.
Figure 2 Analyzer cabin side view.
All electrical and signal connections are on the right side of the analyzer cabinet on a connector plate. All power and signal cables are directed into the cabin through the top of the cabin.
The heated sample gas line can be led into the cabin from several directions according to the cabins installation place. All directions right, left, top, and bottom are possible, but usually the heated sample line is directed into the cabin through the top of the cabin. Sample gas outlet and zero gas inlets are not heated and those lines are directed into and out from the cabin either from the right or the left side of the cabin.
1.1 GASMET CEMS Technical data
This part includes general technical data of the GASMET CEMS. More detailed technical data can be found from “GASMET Cx-Series Instructions & Operating manual” or “GASMET Sampling Unit Instructions & Operating manual”.
1.1.1 General Parameters
Measurement principle: FTIR (Fourier Transform Infrared), Simultaneous analysis of up to 50 gas compounds
Performance: Measures hot, wet and corrosive gas streams. No sample gas dilution or drying.
Gases: Diatomic homonuclear gases (i.e. N2, O2, H2, Cl2) and noble gases (i.e. He, Ne, Ar, Kr) do not absorb infrared radiation. They are the only gases that cannot be measured by the GASMET
Operating temperature: 20 ± 20°C, optimum 15 - 25°C non condensing
Storage temperature: 0 - 60°C, non condensing
Operating system: Windows
Application software: CALCMET for Windows
1.1.2 Sample Gas
Sample Gas Temperature: non-condensing, the sample gas temperature should be the same as the sample cell temperature
Gas Filtration: Filtration of particulates (>2µ) required
Sample Gas pressure: Ambient
1.1.3 Measuring Parameters
Zero point calibration: 24 hours, calibration with nitrogen (5.0 or higher N2 recommended)
Zero point drift: < 2 % of smallest measuring range per zero point calibration interval
Sensitivity drift: none
Linearity deviation: < 2 % of smallest measuring range
Temperature drifts: < 2 % of smallest measuring range per 10 K temperature change
Pressure influence: 1 % change of measuring value for 1 % sample pressure change
Detection limit: 0.2 – 2 ppm (Depending on the application)
Repeatability: <0.01 % of smallest measuring range
Response time: <120 s depending on the gas flow, measurement time and sample cell
1.1.4 Sampling Unit
Sample pump material: 316 SS
Sample pump diaphragms: Teflon
Sample flow: ~4 l/minute
Sample gas pressure: 1.0 bar, max.
Sample gas temperature: 180 °C, max
Particle filter material: Bonded Microfibre
Particle filtration: 2 micron
1.1.5 Sample probe
Sample Probe: SP2000-H
Power density: 800 Watts
Operating temperature: 0 – 180 ºC
Filter element: S-2K 150 2μm, ceramic
Dust loading: < 2 g/m3
Probe Material: SS 316 Viton
Probe length: 1 m
Sample gas temperature (In Stack): 600 ºC max.
Sample gas pressure (In Stack): 0.4 to 6 bar
Mounting flange: DN65PN6
Other probes for higher temperatures and for higher dust loadings on request
1.1.6 Heated Line
Tube size: 4 mm, inner diameter
Core material: Teflon core
Operating pressure: max. 400 kPa
Temperature: max. 200 ºC
Fittings: 6 mm Swagelok or ¼”
Power supply: 230 VAC or 115 VAC
Power density: 120 Watts /meter
The maximum length for the heated line is 30 m with 230 VAC and 15 m with 115 VAC power supply. All analysers are connected together with 1 m heated lines. Other lengths over 30 m (230 VAC) and temperatures by request.
1.1.7 Alarm Outputs
GASMET Industrial Computer controls the outputs. Alarms are freely programmable. Alarm outputs are transferred through relay contacts.
Function: GASMET FTIR / Calcmet software alarm. CEMS can not measure / results are not valid
Service: GASMET FTIR / Calcmet software alarm. CEMS need to be maintained, results are still valid
System: Sampling system alarm, depending of detailed alarm results are valid/not valid
Alarms cannot be switched off, until the problem causing the alarm is fixed. When the system is switched off, Function and System alarms are activated. For more information about the alarms read “Calcmet for Windows Installation and Operating Manual”
1.1.8 Air Conditioning
GASMET CEMS can be equipped with Vortex cooling system or with standard A/C unit. Vortex cooling is recommended in dusty ambient conditions
Normal Cooling Unit:
Cooling capacity: A35°C /A35°C 1150 W, A50°C /A35°C 850 W
Internal Circulation: 500 m3/h
Model: Vortex 308-BSP-35H, System includes 2 Vortex coolers
Cooling capacity: 735 W (air 7 bar, 21 ºC, dew point –40 ºC)
Air consumption: 990 Nl/min, max. / per cooler, Total ~2 m3 max.
Air quality: Pressure 7-10 bar, temperature + 43 ºC, max., dew point –40 ºC