WA:Village Water Ozonization System/VWOS Project Management/VWOS Testing
From The Collaboratory
Contents |
VWOS Testing
Comparison of Water Quality Standards
Tracer Testing
- Prepared salt solution
- 9.0 to 11.0 g of deionized sodium chloride (salt)
- Dissolved in approximately 50 to 70 mL of deionized/distilled water to make a highly concentrated salt solution
- Used just enough water to make the salt crystals dissolve
- Stored in glass vials on loan from the Chemistry Department
- Conducted tracer test
- Turn system on and operate without ozone injection
- Collect one 25 mL water sample from the system before salt solution injection to run as a blank
- Inject salt solution into system through venturi
- Collect system water output in buckets, switching to a new bucket at a consistent interval
- Collect 25 mL samples of water in glass screw top vial from each bucket
- All glass vials were on loan from the Chemistry Department
- Analyzed the samples by Atomic Absorption Spectroscopy
- The Atomic Absorption was used through the chemistry department under advisement of Dr. Richard Schaeffer
- See full procedure via \\collab-main\collabwater\VWOS (Water Purification)\Project Work\System Testing\Tracer Testing\Procedure for Tracer Testing with Equations.doc
- Results
- Calculated Ct value from T10 value obtained by tracer test
- Ct value met standards needed for microorganism inactivation
- See results of tracer tests via \\collab-main\collabwater\VWOS (Water Purification)\Project Work\System Testing\Tracer Testing\tracer test data.xls
- See contact time calculations via \\collab-main\collabwater\VWOS (Water Purification)\Project Work\System Testing\Tracer Testing\Calculations for Contact Time.doc
Microbiological Testing
- 11-4-08 Total Coliform Testing without Ozone
- 11-11-08 Total Coliform Testing with Ozone
- 11-18-08 Total Coliform Testing with Ozone
Materials
- 25 mL and 70 mL glass screw cap vials
- Deionized salt
- Deionized/distilled water
Small and Large Tank Water Testing
- Purpose: to quantify if the system was functioning and compare testing materials
- Materials:
- 5 in 1 aquachek test strips
- nitrate/nitrite test strips
- iron test strips
- paddle tests (aerobic/fecal coliform count)
- petrifilm
- agar plates
- colorimeter
- nitrite/nitrate/iron powder reagents
- Beeches Creek water
- distilled water
- assorted glass/lab/plastic-ware
- Methods
- Cleaned system as the procedure dictated found on Collab-main
- filled tank according to size
- collected pre and post ozone samples
- see full procedures on Collab-main
- Results:
- determined that the system was functioning at acceptable parameters when ORP reached 700, based on small and large tank testing
- ORP is the best real time measurement for quantifying water purity
- paddle tests shown to be inaccurate
- Iron, nitrates, and nitrites test strips were not as accurate as colorimeter testing but were within acceptable testing limits for our purposes
- Petrifilm shows reduction in bacteria counts but is not as sensitive compared to the agar plates
