CEE 453CEE 453Research ProjectResearch Project

Chris GarnicChris GarnicNolan RogersNolan Rogers

Creating Ideal Floc for Instant Startup of a Creating Ideal Floc for Instant Startup of a Conical FlocculatorConical Flocculator

Research GoalsResearch Goals To create a working conical flocculatorTo create a working conical flocculator Find the proper concentrations of clay Find the proper concentrations of clay

and alum to create flocand alum to create floc Create a recipe for mixing procedures Create a recipe for mixing procedures

to create floc in a jar setupto create floc in a jar setup Find the best transfer method from jar Find the best transfer method from jar

to conical flocculatorto conical flocculator Generate acceptable drinking water in Generate acceptable drinking water in

a short time period (Honduras)a short time period (Honduras)

Materials Materials

Peristalic pumpPeristalic pump Mixing DeviceMixing Device Cylinder and cone Cylinder and cone

apparatusapparatus Solenoid valveSolenoid valve Process Controller Process Controller

for flow regulationfor flow regulation Pressure sensor to Pressure sensor to

monitor flowmonitor flow

Assortment of Assortment of tubingtubing

Pump to regulate Pump to regulate sludge blanket sludge blanket height (for height (for prolonged periods prolonged periods of use)of use)

Clay, Alum, NaOHClay, Alum, NaOH pH sensorpH sensor

Supplying influent to reactor Supplying influent to reactor

Delivering influent from the bottom Delivering influent from the bottom via small 5 mm existing ports.via small 5 mm existing ports.

Passing influent down tubing to the Passing influent down tubing to the bottom of the conebottom of the cone

What should the exit velocity of the What should the exit velocity of the influent be? influent be?

InfluentInfluent

Jar TestsJar Tests

2 sets of 6 jar tests 2 sets of 6 jar tests were conducted.were conducted.

5:1 clay to alum 5:1 clay to alum ratioratio

Constant 50 mg/L Constant 50 mg/L alum (turbidities alum (turbidities ranging from 250-ranging from 250-2000 NTU)2000 NTU)

Graph of Jar Test ResultsGraph of Jar Test Results

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Clay (g/L)

Tu

rbit

ity

(NT

U)

Figure 5: Blue line shows the 5:1 clay to alum ratio while the pink line shows the constant 50 mg/L alum solution.

Recipe into the Reactor Recipe into the Reactor

Two different methods tested for Two different methods tested for performance of recipe in reactorperformance of recipe in reactor

Funneling to create instant sludge Funneling to create instant sludge blanket without disturbing clean blanket without disturbing clean water in the upper half of the water in the upper half of the reactor.reactor.

Complete mixing of solution in Complete mixing of solution in reactor reactor

Conical FlocculatorConical Flocculator

What went wrong…What went wrong…

Upside down funnel inside apparatusUpside down funnel inside apparatus Flow rate problems (too low)Flow rate problems (too low) Sodium Bicarbonate (NaHCOSodium Bicarbonate (NaHCO33) versus ) versus

Sodium Hydroxide (NaOH) for pH Sodium Hydroxide (NaOH) for pH adjustmentadjustment

Settling basin was too small and Settling basin was too small and turbulence mixed up settling flocturbulence mixed up settling floc

Settling BasinSettling Basin

Recipe for Instant FlocRecipe for Instant Floc Add water to jar (amount of water would Add water to jar (amount of water would

be 25% reactor volume)be 25% reactor volume) Mix in 12 g/L clay, 2.4 g/L alumMix in 12 g/L clay, 2.4 g/L alum Adjust for pH by adding 0.87 grams NaOH Adjust for pH by adding 0.87 grams NaOH (For each gram of alum add .364 grams of (For each gram of alum add .364 grams of

NaOH) NaOH) Fast mix solution at 100 rpm for 1 minuteFast mix solution at 100 rpm for 1 minute Slow mix solution at 30 rpm for 20 minutesSlow mix solution at 30 rpm for 20 minutes Add solution to reactor (that is already Add solution to reactor (that is already

75% full of water)75% full of water) Completely mix water and solutionCompletely mix water and solution

ConclusionsConclusions

Our recipe for floc produced 2.15 Our recipe for floc produced 2.15 NTU effluent water NTU effluent water

Drinking water standards could be Drinking water standards could be met via filtrationmet via filtration

Floc can be produced in a jar test!Floc can be produced in a jar test! We effectively decreased the startup We effectively decreased the startup

time of the conical flocculator to time of the conical flocculator to about 0.5 hours. about 0.5 hours.

Suggestions/CommentsSuggestions/Comments

Test different cone angles and sizesTest different cone angles and sizes Test different flow ratesTest different flow rates Test the effects of scaling up Test the effects of scaling up

(Honduras)(Honduras)