Presentation on theme: "SMOKE DENSITY MEASUREMENT"— Presentation transcript:
1 SMOKE DENSITY MEASUREMENT Particles emitted give rise to a nuisance factorPlume visibility and haze due to finer particlesGround level deposits in the case of larger particlesAppearance of plume assessed according to Ringelmann scale of plume greynessUsed for spot checkShades of grey from white to blackRingelmann 0 (white) to Ringelmann 5 (Black) in steps of 20% obscuration<40% or Ringelmann 2 is legal requirement
2 SMOKE METER Photo cell type Focused light beam through the duct or chimney on a photo cellVariation in signal of the photo cell a measure of variation in obscuration of light source due to smoke and dustDifference exists between what the meter shows and Ringelmann chart as Light path and chimney diameter not same
3 SMOKE METER Deposits of particles on the camera lens and Receiver Aluminium tubes of length (4:1 dia for coarser and 16:1 for finer ) eliminates depositsZero drift due to ageing of components and dustMisalignment of lamp and photocell with duct distortions more so with everclean windowsTo be installed platforms not attached to duct.
4 DUST MONITORS Knowledge of dust emission as weight per unit volume Got from dust samplesContinuous monitoringDirect measurement on weight basis not given by instrumentsCalibration done through dust samples and indication as a function of particle sizeParticle size grading does not change (assumed)
6 CERL flue dust monitorCollects dust samples periodically and measures obscuration caused by this collectionA glass plate collects the dust and after measurement, dust blown away with compressed airFavors larger particles, hence warns of emission likely to cause nuisance.Recorder consists of circular chart with radial lines drawn proportional to dust.
7 AEI Flue dust monitor Withdraws a continuous sample of dusty gas Given a swirl it results in electricity due to to frictionMeasurement of this static electricity is a measure of dust
8 SEROP dust monitor Records light scattered by dust An emitter beams light on to dust flow and scattered light collected by a photocellNo alignment problemScans larger volumeFree from corrosion as components are outside.