210 likes | 307 Vues
Design and Operation of a Remote Phosphorus Analyzer. David M. Struve Supervising Chemist Water Quality Analysis Division South Florida Water Management District. “On mechanical slavery, on the slaver of the machine, the future of the world depends.†Oscar Wilde.
E N D
Design and Operation of a Remote Phosphorus Analyzer David M. Struve Supervising Chemist Water Quality Analysis Division South Florida Water Management District
“On mechanical slavery, on the slaver of the machine, the future of the world depends.” Oscar Wilde
Considerations for Remote Analysis • Reliability • Accuracy and Precision • Communication and Control • Flexibility and Speed • Maintenance • Waste and the Environment
Benefits of Remote Analysis • Data generated 24/7, rain or shine • Ability to observe short term trends • No travel time • No sample handling • No lab costs • Higher Frequency of Analysis • Event Driven
Design Parameters for Phosphorous Determinations • Use a standard chemistry • Results comparable to lab analyses • Control analyzer temperature • Determine total and reactive portions • Easy access to all data • Fault detection • Low maintenance • Calibration standards “on board”
Project Overview • System developed by Greenspan Technology, Australia • Deployed February 2002 • System uses standard molybdate chemistry (SM4500PF) • 3 point calibration and color correction • 3 month maintenance cycle • CPDP Modem Technology • Deployed at STA1W - Site G310
Thermal Digest UV Digest AIR 02 05 STD 1 Switch V17 20 STD 2 Chamber 1 23 STD 3 SAMPLE NC 25 P0 - 8 Channel 60:1 1/8” ID 05-40 rpm V12 D2 32 NO V10 NC NO 31 Air Wash D1 22 NC AIR 30 V14 04 Wash V11 NO NO NC AIR 01 AIR 00 Waste 2 Waste 2 Chamber 2 03 Wash 06 Color 1 21 Color 2 Water Trap Surfactant 24 Detector P1 30:1 1/8” ID 10-65 rpm 26 Waste 3 Color 3 NC NO V16 V 13 NC NO Waste 1 Waste 2 V 27 NO Air NC
Analytical Conditions • Sampling frequency • Sample intake • 3 point calibration (0 – 124 ppb P) • Determination of reactive phosphorous • Sample digestion • Determination of total phosphorous • Monitoring of digester temperature, cabinet temperature, leak detectors, reagent volumes
Overall Observations • Comparative results excellent • Good detection limits (~4ppb) • Communications flawless • Control and error detection good • Interesting data
The Project Team • Greenspan Technology • Robert Briggs • Chris Gibson • Tom Baber • Bill Harrington • Dr. Meifang Zhou • Kim Hanes • AirLink Communications • SFWMD