Jar Test Labsheet

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FACULTY OF CIVIL AND ENVIRONMENTAL ENGINEERING

DEPARTMENT OF WATER AND ENVIRONMENTAL

ENGINEERING

ENVIRONMENTAL ENGINEERING LABORATORY

LABORATORY INSTRUCTION SHEET

SUBJECT CODE

BFC3121

EXPERIMENT CODE

MA4

TEST

JAR TEST

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DEPARTMENT OF WATER AND ENVIRONMENTAL

ENGINEERING

ENVIRONMENTAL ENGINEERING LABORATORY

SHORT REPORT

SUBJECT CODE

CODE & EXPERIMENT

TITLE

COURSE CODE

EXPERIMENT DATE

NAME OF STUDENT

NO. OF GROUP

NAME OF GROUP

MEMBERS

1.

2.

3.

4.

5. NAME OF LECTURER/

TUTOR/TRAINER

DATE OF SUBMISSION

MARK

DISCIPLINE / PARTICIPATION

/15%

RESULT

/25%

DATA ANALYSIS

/30%

DISCUSSION

/30%

TOTAL

/100%

EXAMINER’S COMMENT

APPROVAL RECEIVE

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FACULTY : CIVIL AND ENVIRONMENTAL

ENGINEERING NO. OF PAGES : 1/6

DEPARTMENT : WATER AND ENVIRONMENTAL ENGINEERING

EDITION : MA4

REVISION NO. : 04

LAB : ENVIRONMENTAL ENGINEERING EFFECTIVE DATE : 0112/2007

TEST : JAR TEST AMENDMENT DATE : 20/11/2007

1.0 OBJECTIVE

 To determine the optimal coagulant dose which will produce the highest removal of a given water turbidity.

2.0 LEARNING OUTCOME

1. To identify the most common coagulant used in the coagulant process.

2. To determine the most effective and optimum dosage of coagulant for a particular mixing intensity and duration.

3. To understand the complex interrelationships that exists between the chemicals and the constituents of the water being treated, as well as other factors such as pH, temperature, the intensity and duration of mixing.

3.0 THEORY

Raw water and wastewater is normally turbid containing solid particles of varying sizes. Particles with sizes greater than 50 µm settle fairly rapidly. The settling velocities of colloidal particles of sizes less than 50 µm are very slow. Thus, these particles are encouraged to collide leading to coalescence of particle to form flocs particles, which are bigger and heavier. These particles will have higher settling velocities and easily settle out. Colloidal particles do not agglomerate by itself due to the presence of repulsive surface forces. A process is needed to suppress these forces so as to allow flocs formation. This process is called coagulation process. It is actually the addiction of chemical coagulant to the raw water or wastewater. Coagulant that are normally used are salts of aluminium namely aluminium sulphate and ferric salts namely ferrous sulphate and ferric chloride. The next processs that follows the coagulation process is flocculation. It is the process that promotes particles collision due to gentle agitation resulting in agglomeration of smaller non-settleable particles into flocs (bigger particles) which settles easily to produce clarified water. Addition of coagulant aid such as synthetic polymer will accelerate settling.

PREPARED BY : AZRA MUNIRAH MAT DAUD

SIGNATURE :

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DEPARTMENT : WATER RESOURCE AND ENVIRONMENTAL

ENGINEERING

EDITION : MA4

REVISION NO. : 04

LAB : ENVIRONMENTAL ENGINEERING EFFECTIVE DATE : 01/12/2007

4.0 EQUIPMENTS AND MATERIALS

1. Jar test apparatus with six rotating paddles blade 2. Six (6) beakers

3. pH meter 4. Turbidity meter 5. Pipette

REAGENT

1. Aluminum sulfate (alum) with a known concentration or anionic/cationic coagulant such as ferrous sulfate and ferric chloride.

5.0 PROCEDURES

1.0 Select any coagulant aid from the bench.

2.0 Prepare samples of wastewater into six different beakers with one litre each and label the

beakers.

3.0 Add in coagulant aid with different dosage and one control sample. 4.0 Run the experiment.

5.0 Observe the results.

SIGNATURE :

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ENGINEERING

EDITION : MA4

REVISION NO. : 04

6.0 RESULTS AND CALCULATION

Fill in the table provided in the bench sheet.

7.0 DATA ANALYSIS

1. Compare the level of turbidity in each sample.

2. With the aid of a graph, show the relationship between pH and turbidity with respect to coagulant dosage. 3. From the graph, get the optimum value for pH and coagulant dose of the coagulation process.

4. Explain the implications of using different dosage of aluminium sulphate in the treatment process

8.0 DISCUSSION

1. By using aluminium sulphate, the mechanism is : Al3+ + 3H2O  Al(OH)3 + 3H

Describe the mechanism of reaction if the aluminium sulphate is replaced by ferum chloride (FeCl3).

2. How the coagulant works?

3. Name three types of acid and base which are suitables for pH neutralization. 4. What are the benefits of using coagulant aids?

5. In what way the dosage of aluminium sulphate in the treatment process can be reduced? 6. Instead of Al2(SO4)3, name another three coagulants that can be best used as coagulant aid.

SIGNATURE :

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DEPARTMENT : WATER RESOURCE AND ENVIRONMENTAL ENGINEERING

EDITION : MA4

REVISION NO. : 04

Figure 1: Scale for measurement of floc sizes

Scale for measurement of floc sizes

Very fine

Very fine / fine

Fine

Moderately fine

Moderate

Coarse

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ENGINEERING

EDITION : MA4

REVISION NO. : 04

9.0 BENCH SHEET

JAR TEST 1 (Set the coagulant dose)

Initial turbidity : _______ NTU Initial pH : _______ pH adjustment (base) : ______ mg/L of ____________ pH adjustment (acid) : ______ mg/L of ___________ Coagulant concentration : _______ mg/L Jar No 1 2 3 4 5 6 pH Coagulant dose (mg/L) 1 2 3 4 5 control

Agitate (minute) none

Fast (rpm) none

Slow (rpm) none

Settling depth (mm)

Turbidity (NTU)

Floc formation (final 10 minutes) *

* Floc formation can be recorded by referring to the measurement scale as depicted in Figure 1.

SIGNATURE :

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ENGINEERING

EDITION : MA4

REVISION NO. : 04

JAR TEST 2 (Set the pH value)

Initial turbidity : _______ NTU Initial pH : _______ pH adjustment (base) : ______ mg/L of ____________ pH adjustment (acid) : ______ mg/L of ___________ Coagulant concentration : _______ mg/L Jar No 1 2 3 4 5 6 pH 6.0 6.0 6.0 6.0 6.0 6.0 Coagulant dose (mg/L) control

Agitate (minute) none

Fast (rpm) none

Slow (rpm) none

Settling depth (mm)

Turbidity (NTU)

Floc formation (final 10 minutes) *

* Floc formation can be recorded by referring to the measurement scale as depicted in Figure 1.

SIGNATURE :

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