![Results
1.)
A dosage of 40 milligrams per liter resulted in the lowest total solid (TS) in the
supernatant.
This dosage corresponded with the lowest turbidity as well; turbidity being 0.7.
2.) The pH and alkalinity varied because they go hand in hand with the coagulation process.
Different levels of the dosage used resulted in different pH and alkalinity levels.
3.) Yes, restabilization occurred with the Kanawha River sample. The alum dosage of fifty and
sixty milligrams per liter both resulted in higher TS in the supernatant; while an alum dosage of
forty milligrams per liter yielded the lowest TS.
4.) 2 mgd*3.7854 = 7570800 L/day * 64 mg/L /1000000 = 484.53 kg/day
[2 Al(OH)3] = 1.35x10-4 M = 21.06 kg Estimated Solids = 484.53+21.06= 505.59 kg
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ParameterValues
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Parameters vs. CoagulantDosage
Supernatant Alkalinity Total Solids Turbidity pH](https://image.slidesharecdn.com/01cb5730-7822-435f-bc02-a6a796c6cbd9-161211212553/85/ENVIRONMENTAL-LAB-REPORT-6-3-320.jpg)
ENVIRONMENTAL LAB REPORT - 6
- 1. ENVIRONMENTAL LAB REPORT CE 347 Lab 6 – Jar Tests Introduction The purpose of the experimentwastodetermine the optimumamountof coagulanttobe addedto a raw watersource in orderto remove the colloids;the watersource usedwasfromthe KanawhaRiver.In orderto selectthe bestdosage amount,a jar testwasconducted,inwhichsix square twoliterjarswere filledwithrawwater.Eachjar had a specificamountof coagulantaddedtoit.The coagulantusedforthe experimentwasalum, asithas a three pluscharge,whichmade it an effective coagulant. The resultsforthe bestcoagulantdosage tobe usedonthe KanawhaRiverwatersampleswere determinedthroughanarray of differentdatacalculatedfromthe experiment,whichincluded: respective coagulantdosage aswellasthe coagulantvolume added,the pH,alkalinity(mg/lasCaCO3), respective total solids (TS),andturbidity. Toconductthe experiment,alumwasaddedinvarying amountsto eachrespective jarandthoroughlymixedat ahighspeedforthirtyseconds,withmetal paddle mixers.Afterthatthe speedwasreducedandcontinuedturningforaperiodof twentyminutes; thisallowedforflocculationtotake place.Once the flocculationperiodwasover,the paddleswere removed andthe flocsettledtothe bottomof the jars;overa periodof fiftyminutes. A pipette wasusedtoremove watersamplesfromeachrespective jar;the openingof the pipette was gentlyplacedjustunderthe surface of the waterwhichhelpedthe flocremainonthe bottomof the jar as the watersample wasnot stirredup.Once the fiftymillilitersampleswere removedfromeach respective jar,theywere testedtoobtainthe aforementionedresults. The procedure usedtoobtainthe resultsof the experimentisasfollows. Fourteenglasscrucibleswere markedand weighedforthe TSmeasurements.Next,alkalinitywasmeasuredthree timesforthe raw water.Two samplesof fiftymilliliterseachof the raw waterwere placedinglasscruciblesandplacedin the ovento dry forTS data.The six jarswere filledwithraw waterto the twoliter markand respective volumesof alumwere added.Afterthe alumwasadded,the sampleswere flashmixedforthirty secondsat a highspeed;the speedwasreducedafterthirtysecondsandthe paddles slowlyturnedfor twentyminutes,whichincreasedthe floc size.Afterthe flocculationperiod,the mixerswere removed and the sampleswere leftuntouchedforfiftyminuteswhichallowedthe agglomerate tosettletothe bottomof the jars.
- 2. Finally,fiftymillilitersampleswerecarefullyextractedfromthe jars andthe experimental testswere conductedforeach respective jarwhichcontaineddifferentalumdosages. Data Parameter Raw Water Jar 1 Jar 2 Jar 3 Jar 4 Jar 5 Jar 6 Coagulant Dosage (mg/L) 0 10 20 30 40 50 60 Coagulant Volume Added (mL) pH 7.93 7.87 7.51 7.35 7.12 7.05 6.79 Alkalinity (mg/liter as CaCO3) 50.7 40.2 38 38 36 30 22 Container Number 24 18 1 30 8 29 5 Weight (g) 52.9411 52.5623 34.3596 37.0468 42.4112 34.1856 34.0242 Container w/ TS (g) 52.9464 52.5675 34.3645 37.0522 42.4144 34.1902 34.0298 Total Solids 0.106 0.104 0.098 0.108 0.064 0.092 0.112 Container Number 25 33 56 9 15 121 4 Weight (g) 40.1265 33.0876 38.3654 38.3217 44.4826 36.9423 40.755 Container w/ TS (g) 40.1318 33.0928 38.3719 38.3271 44.4836 36.9423 40.755 Total Solids 0.106 0.104 0.13 0.108 0.02 0 0 TS Sample Volume (mL) 50 50 50 50 50 50 50 Turbidity (NTU) 4.5 5.66 2.71 1.22 0.7 1.04 1 Total Solids 106 104 114 108 42 46 56
- 3. Results 1.) A dosage of 40 milligrams per liter resulted in the lowest total solid (TS) in the supernatant. This dosage corresponded with the lowest turbidity as well; turbidity being 0.7. 2.) The pH and alkalinity varied because they go hand in hand with the coagulation process. Different levels of the dosage used resulted in different pH and alkalinity levels. 3.) Yes, restabilization occurred with the Kanawha River sample. The alum dosage of fifty and sixty milligrams per liter both resulted in higher TS in the supernatant; while an alum dosage of forty milligrams per liter yielded the lowest TS. 4.) 2 mgd*3.7854 = 7570800 L/day * 64 mg/L /1000000 = 484.53 kg/day [2 Al(OH)3] = 1.35x10-4 M = 21.06 kg Estimated Solids = 484.53+21.06= 505.59 kg 0 1 2 3 4 5 6 7 8 9 0 20 40 60 80 100 120 0 10 20 30 40 50 60 70 pH/TurbidityLevels ParameterValues CoagulantDosage(mg/L) Parameters vs. CoagulantDosage Supernatant Alkalinity Total Solids Turbidity pH