CalculationofRangeofDilutionsforAcceptableBODResults：可接受的范围内计算结果稀释BOD.ppt

1、Calculation of Range of Dilutions for Acceptable BOD Results,Prepared By Michigan Department of Environmental Quality Operator Training and Certification Unit,BOD PROCEDURE,DILUTE SAMPLE,Minimum Residual, 1.0 mg/L Minimum Depletion, 2.0 mg/L At Least Two Dilutions,Calculation of Range of Acceptable

2、BOD Results,Lowest (Minimum) Acceptable Results, Lowest Acceptable Depletion,Example,What is the Lowest Acceptable BOD results if 20 mL of sample is used?,Minimum Acceptable BOD = 30 mg/L,Minimum BOD That May Be Reported =,600,Sample Volume,Example 2,What is the Lowest Acceptable BOD results if 150

3、mL of sample is used?,Minimum Acceptable BOD = 4 mg/L,Calculation of Range of Acceptable BOD Results,Highest (Maximum) Acceptable Results,ASSUMING Initial D.O. of 8.0 mg/L,Lowest Acceptable Residual, Highest Acceptable Depletion,Depletion = 8.0 - 1.0 = 7.0,Example,What is the highest Acceptable BOD

4、results if 20 mL of sample is used?,Maximum Acceptable BOD = 105 mg/L,Maximum BOD That May Be Reported =,2100,Sample Volume,Example 2,What is the highest Acceptable BOD results if 150 mL of sample is used?,Maximum Acceptable BOD = 14 mg/L,Maximum BOD That May Be Reported =,2100,Sample Volume,Calcula

5、tion of Range of Acceptable BOD Results,Summary,Calculation of Range of Acceptable BOD Results,Wait A Minute,600 X 3.5 = 2100,So (assuming D.O. In is 8.0),Minimum BOD x 3.5 = Maximum BOD,Calculation of Range of Acceptable BOD Results,Summary (again),Example,What is the Lowest Acceptable BOD results

6、if 30 mL of sample is used?,= 20 mg/L,What is the Highest Acceptable BOD results if 30 mL of sample is used?,20 mg/L X 3.5,= 70 mg/L,Total Range when using a 30 mL sample:,20 to 70 mg/L,Total Range when using a 100 mL sample = 6 to 21 mg/L,Total Range when using a 150 mL sample = 4 to 14 mg/L,Total

7、Range when using 100 mL and 150 mL (two Bottles),Total Range when using a 50 mL sample = 12 to 42 mg/L,= 4 to 21 mg/L,Total Range when using 50 mL and 150 mL (two Bottles),= 4 to 42 mg/L,OVERLAP From 6 to 14 mg/L,OVERLAP From 12 to 14 mg/L,Total Range when using a 25 mL sample = 24 to 84 mg/L,Total

8、Range when using a 125 mL sample = 4.8 to 16.8 mg/L,Total Range when using 25 mL and 125 mL (two Bottles),NO: Does Not Include 16.8 to 24 mg/L,= 4.8 to 84 mg/L,Range To Wide (No Overlap),?,Calculate Range of Acceptable BOD Results,Use Two Volumes that Expand the Range But Give a “Comfortable” Overlap,Calculate Range of Acceptable BOD Results,Use Two Volumes that Expand the Range But Give a “Comfortable” Overlap,Calculate Range of Acceptable BOD Results,Use Two Volumes that Expand the Range But Give a “Comfortable” Overlap,Calculation of Range