Measurement of dust concentration in dry or moist, steamsaturated and corrosive stack gases Monitoring of municipal and hazardous waste and sewage sludge incinerators Monitoring of power plants Measurement of dust concentration in hot gases with special configurations Extractive system with heating of sample Built in compliance with EN 14181 Automatic zero and reference point checking Easy adjustment with checking rods Maximum sensitivity in the µg/dscm range DUST EMISSION MONITORING SYSTEM S TA

DUST EMISSION MONITORING SYSTEM S TA C K G U A R D Dust concentration measurement light source Dust particles in the stack gas scatter the light of a beam passed through the gas. Measurement of the scattered light intensity is therefore a reliable indicator of the sample’s dust particle concentration. transmitted light 20° scattered light Extractive measurement In most countries, the admissible dust concentration emitted by large incinerators, power plants and dust extraction plants is limited by law. Continuous measurement of the concentration is mandatory. The moisture content of the stack...

As a rule, measurements of dust content are required to state the concentration in mg/m3 or mg/dscm. But the intensity of the scattered light produced by a given dust particle depends greatly on particle characteristics such as size, shape, colour, relative density, etc. Consequently, an absolute measurement of the dust concentration in mg/dscm is achievable only with an application-specific calibration. The calibration curve is obtained by comparing the measured value with a manual gravimetric measurement. Application of the curve makes it possible to state the measured value directly in mg/dscm...

Control unit SIGAR 2 Besides delivering and displaying the readings, the SIGAR 2 control unit controls the entire monitoring system with its heaters, valves and fans. With its two-line LC display and operating structure employing plain text guidance, SIGAR 2 affords easy access to the StackGuard for operation, configuration and servicing. It has two 0/4 .. 20 mA current outputs and five relays configurable as limit or alarm contacts. An optional bus coupler available for connection to PROFIBUS DP enables direct data transmission and instrument control via the digital interface.

System concept A ring pipe system (a) with a large diameter of 40 mm carries the gas being monitored with high velocity to the instrument (b) and back into the stack gas duct (c). This arrangement reduces deposits to a minimum. In the ring pipe, the gas is heated with heating elements (d) to the required temperature above the dew point. The sample is withdrawn from the ring pipe close to the photometer and then returned to it after measurement. Withdrawal is powered by a radial fan (e). In the event of a malfunction, shutoff valves (f) isolate the monitoring system from the stack to protect it...

S P E C I F I C AT I O N S 20° scattered light measurement 0 ... 100 PLA 0.. 0,05/0 .. 0,1/0 .. 0,3/0 .. 1/0 .. 3/0 .. 10/0 .. 30/0 .. 100 PLA ± 0,0002 PLA 650 nm Photometer StackGuard Sample temperature: Sample pressure: Flow rate: Ambient temperature: Ambient humidity: Weight: Protection degree: Ring Pipe Flow rate: Weight: Pipe length: Stack connections: Protection degree: 790 .. 930 l/min @ 160°C ca. 240 kg (standard version) max. 25 m overall length DN65 PN6 with flange DIN 2641 or to customer spec IP40 (additional insulation required for outdoor installation) Control Unit SIGAR 2 Power...