On-Site Assessment of Compliance On-Site Assessment of Compliance - PowerPoint PPT Presentation

On-Site Assessment of Compliance On-Site Assessment of Compliance Monitoring - Particulate Species Monitoring - Particulate Species Dave Scott & Alan Leonard Dave Scott & Alan Leonard AEA Technology Environment AEA Technology Environment

Important Points Important Points - Particle Sampling (I) - Particle Sampling (I) Sampling of Particulate Phase Pollutant Sampling of Particulate Phase Pollutant Species Need to Address the Following Species Need to Address the Following Important Points: Important Points: g Inertial effects Inertial effects g g Choosing a suitable sampling position Choosing a suitable sampling position g g Normally sampling has to be Normally sampling has to be isokinetic isokinetic g « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Points Important Points - Particle Sampling (II) - Particle Sampling (II) A sharp sampling nozzle is required. A sharp sampling nozzle is required. g Avoidance of condensation is important. Avoidance of condensation is important. g g Probe losses need to be avoided or assessed. Probe losses need to be avoided or assessed. g g Minimum particle retention efficiency needs to be Minimum particle retention efficiency needs to be g met. met. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Points Important Points - Particle Sampling (III) - Particle Sampling (III) Use of inert or special materials may be required (eg eg Use of inert or special materials may be required ( for dioxins or metals). for dioxins or metals). g Cumulative sampling strategy normally required. Cumulative sampling strategy normally required. g g Product of nozzle area and sampling time to remain Product of nozzle area and sampling time to remain g constant. constant. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Points Important Points - Particle Sampling (IV) - Particle Sampling (IV) Other minimum criteria need to be satisfied, eg eg: : Other minimum criteria need to be satisfied, -minimum sampling times -minimum sampling times -minimum sampled weights -minimum sampled weights -minimum numbers of sampling points on -minimum numbers of sampling points on -a specified grid plane at centers centers of equal areas of equal areas -a specified grid plane at « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Particle Sampling Standards (I) Particle Sampling Standards (I) g Standard methods are all extractive Standard methods are all extractive gravimetric gravimetric. . g g Continuous particle monitors need to be calibrated Continuous particle monitors need to be calibrated g against standard methods. against standard methods. g In UK, BS 3405 predominates (accuracy only +/ - In UK, BS 3405 predominates (accuracy only +/ - g 25%) and duplicate sampling required. 25%) and duplicate sampling required. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Particle Sampling Standards (II) Particle Sampling Standards (II) More Accurate Standards Now Available: More Accurate Standards Now Available: eg, both US EPA Method 5 and ISO 9096 offer , both US EPA Method 5 and ISO 9096 offer eg accuracy of +/ - 10% based on single samples and accuracy of +/ - 10% based on single samples and concentrations > 50 mg m-3. concentrations > 50 mg m-3. g Low concentration methods (< 10 mg m-3) now to Low concentration methods (< 10 mg m-3) now to g be voted on at CEN and ISO. be voted on at CEN and ISO. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Particle Samplers Particle Samplers BS 3405 written around older systems, such as BS 3405 written around older systems, such as BCURA and MK III A. BCURA and MK III A. g Newer standards normally require more Newer standards normally require more g sophisticated samplers, such as Andersen or sophisticated samplers, such as Andersen or Zambelli (Manual or Automatic) (Manual or Automatic) Zambelli « = NVVU= ^ b^ = qÉÅ Üåç logy plc

BS 3405: Location Requirements BS 3405: Location Requirements g Ideally in flue shortly before discharge point. Ideally in flue shortly before discharge point. g g Verticle Verticle gas flow preferred. gas flow preferred. g g Downstream of any abatement plant. Downstream of any abatement plant. g g Straight length of flue required Straight length of flue required g « = NVVU= ^ b^ = qÉÅ Üåç logy plc

BS 3405: Minimum Distance from BS 3405: Minimum Distance from Obstructions Obstructions g > 1D upstream and >2D downstream of bend or > 1D upstream and >2D downstream of bend or g junction. junction. g > 4D downstream of fan. > 4D downstream of fan. g g >3D downstream of dampers or >3D downstream of dampers or louvres louvres (unless fully (unless fully g open. open. g >1 exit diameter upstream of point of emission >1 exit diameter upstream of point of emission g « = NVVU= ^ b^ = qÉÅ Üåç logy plc

BS 3405 - Minimum Acceptable Flow BS 3405 - Minimum Acceptable Flow and Temperature Profile and Temperature Profile g Ratio of highest to lowest gas velocity to be <3:1. Ratio of highest to lowest gas velocity to be <3:1. g g Ratio of highest to lowest Ratio of highest to lowest dP dP to be <9:1. to be <9:1. g g Angle of flow at any point to be < 20 Angle of flow at any point to be < 20 Deg Deg. . g g Absolute temperature variation across plane not to Absolute temperature variation across plane not to g exceed 10% of mean value. exceed 10% of mean value. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

BS 3405 - Minimum Numbers of BS 3405 - Minimum Numbers of Sampling Points on Grid Plane Sampling Points on Grid Plane g If sampling plane <2.5 m2, then at least 4 points If sampling plane <2.5 m2, then at least 4 points g required. required. g If sampling plane >2.5 m2, then at least 8 points If sampling plane >2.5 m2, then at least 8 points g required. required. g If ratio of highest If ratio of highest dP dP >4:1 but < than 9:1, then 8 >4:1 but < than 9:1, then 8 g points required. points required. « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Other Particle Standards Other Particle Standards g The more accurate standards have more stringent The more accurate standards have more stringent g requirements. In general accuracy improved by: requirements. In general accuracy improved by: - tighter temperature / velocity profiling - tighter temperature / velocity profiling - sampling at more points - sampling at more points - sampling for longer - sampling for longer - stricter attention to maintaining isokineticity isokineticity - stricter attention to maintaining - better sample volume measurement - better sample volume measurement « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Essential Components Essential Components g Nozzle Nozzle g g Sampling probe Sampling probe g g In-stack or out-stack filter In-stack or out-stack filter g g Sample gas conditioning (if necessary) Sample gas conditioning (if necessary) g g Sample flow rate measurement device Sample flow rate measurement device g g Sample pump Sample pump g g Flow control valve Flow control valve g g Flue gas velocity measurement device Flue gas velocity measurement device g g Flue gas temperature measurement device Flue gas temperature measurement device g « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Factors Important Factors « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Factors Important Factors « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Factors Important Factors « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Important Factors Important Factors « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Particle Sampling Systems (I) Particle Sampling Systems (I) « = NVVU= ^ b^ = qÉÅ Üåç logy plc

Particle Sampling Systems (II) Particle Sampling Systems (II) « = NVVU= ^ b^ = qÉÅ Üåç logy plc