Dissertation Defense for the Degree of Ph.D. January 19, 2006 …sorialga/Biofilter Website/s... · Dissertation Defense for the Degree of Ph.D. January 19, 2006 Daekeun Kim • VOCs

Dissertation Defense for the Degree of Ph.D.

January 19, 2006

Daekeun Kim

• VOCs ?

Volatile organic compounds (VOCs)

- They are found in the waste stream emitted from most processes employing organic or petroleum based solvents.

- A cost-effective technology: Biological treatment technology(biofiltration)

•• Transient loadingTransient loading

•• NonNon--use periodsuse periods

•• Biomass accumulationBiomass accumulation

•• Microbial activityMicrobial activity

Adsorption unit can be a buffer unit for a biofilter

• Proposed Technology: Integrated treatment schemeAdsorptionAdsorption + + BiofiltrationBiofiltration

To develop an innovative technology for To develop an innovative technology for VOCsVOCs removal from removal from waste gas with longwaste gas with long--term, stable, high removal (>99%) term, stable, high removal (>99%) performanceperformance

Development of Integrated TechnologyDevelopment of Integrated Technology

Phase IPhase I: : BiofilterBiofilter StudyStudy Phase IIPhase II: Adsorption Study: Adsorption Study

•• Removal PerformanceRemoval Performance

•• Biomass Distribution Biomass Distribution & Activity& Activity

•• Adsorption IsothermAdsorption Isotherm

•• 22--Bed Adsorption UnitBed Adsorption Unit

Phase IIIPhase III: : Evaluation of Integrated Treatment SchemeEvaluation of Integrated Treatment Scheme

• Objectives

To characterize Trickle Bed Air To characterize Trickle Bed Air BiofilterBiofilter (TBAB) performance treating (TBAB) performance treating different single different single VOCsVOCs under adverse operating conditions under adverse operating conditions

• Objectives

• Specific Objectives

To characterize Trickle Bed Air To characterize Trickle Bed Air BiofilterBiofilter (TBAB) performance treating (TBAB) performance treating different single different single VOCsVOCs under adverse operating conditions under adverse operating conditions

•• Determine the critical loading capacity of TBAB for target Determine the critical loading capacity of TBAB for target VOCsVOCs•• Determine the impact of nonDetermine the impact of non--use periods on TBAB performance use periods on TBAB performance

under different organic loading rates.under different organic loading rates.

• Target VOCs: (Paint booth industry)

1.090.283.162.58LogKow

0.000620.001940.1090.280K’H

Methyl isobutyl ketone (MIBK)

Methyl ethyl ketone (MEK)

StyreneToluene

Hydrophilic compoundsHydrophobic compounds

K’H

= dimensionless Henry’s law constant, Kow

= Octanol-water partition

coefficient

• Experimental Methods

• Reactor : Independent lab-scale TBAB

Dimension: 76 mm (D) ×× 130 cm (L)130 cm (L)

Operating Temperature: 20Operating Temperature: 20ooCC

• Media: pelletized biological support media

• Experimental Strategies

•• BackwashingBackwashing (as biomass control, 1 hour/ 1 week)

•• NonNon--use periodsuse periods-- Starvation Starvation (without contaminant loading, 2 days/ 1 week)

-- Stagnant Stagnant (without any flows, 2 days/ 1 week) (without any flows, 2 days/ 1 week)

• Experimental Conditions

0.760.761.51 ~ 2.021.23EBRT,min

1.09 ~ 5.430.7 ~ 7.030.64 ~ 3.170.7 ~ 7.03Loading rate

kg COD/m3·day

50 ~ 25050 ~ 50050 ~ 33050 ~ 500Inlet Conc.,

ppmv

MIBKMEKStyreneToluene

• Results - VOC removal capacity- Correlation between critical loading rate & Kow

- Biofilter response after Backwashing & Non-use periods: Toluene, MEK

- Biomass distribution: VS, EPS (proteins & total carbohydrates)

• Results - VOC removal capacity - Correlation between critical loading rate & Kow



• Results – VOC removal capacity (Backwashing)

Aromatic compounds

Toluene• Critical loading

3.5 kg COD/m3·day

Loading rate, kg COD/m3day

0 2 4 6 8

Rem

oval

rat

e, k

g C

OD

/m3 da

y

0

2

4

6

8

Toluene100% Removal


Aromatic compounds

Styrene• Critical loading

1.9 kg COD/m3·day


0 2 4 6 8

Rem

oval

rat

e, k

g C

OD

/m3 da

y

0

2

4

6

8

StyreneToluene100% Removal


Oxygenated compounds

MEK• Critical loading

5.6 kg COD/m3·day


0 2 4 6 8

Rem

oval

rat

e, k

g C

OD

/m3 da

y

0

2

4

6

8

MEKTolueneStyrene100% Removal


Oxygenated compounds

MIBK• Critical loading

4.3 kg COD/m3·day


0 2 4 6 8

Rem

oval

rat

e, k

g C

OD

/m3 da

y

0

2

4

6

8

MIBKTolueneStyreneMEK100% Removal

• Results – Comparison of VOC removal capacity

VOC Loading/Removal Rate, kgCOD/m3day

0 2 4 6 8

Toluene

Styrene

MEK

MIBK

Loading

5.43

7.03

3.17

7.03

• Results – VOC removal capacity


0 2 4 6 8

Toluene

Styrene

MEK

MIBK

LoadingBackwashing5.43

7.03

3.17

7.03

4.34

5.64

1.9

3.52

• Results – VOC removal capacity


0 2 4 6 8

Toluene

Styrene

MEK

MIBK

LoadingBackwashingNon-use Period

5.43

7.03

3.17

7.03

4.342.17

4.35.64

1.271.9

3.52

• Results - VOC removal capacity- Correlation between critical loading rate & VOC properties- Biofilter response after Backwashing & Non-use periods

: Toluene, MEK- Biomass distribution

: VS, EPS (proteins & total carbohydrates)

• Results – Critical loading vs. Kow

Kow (octanol-water partition coefficient)

0.1 1 10 100 1000 10000

Cri

tica

l loa

ding

, kg

CO

D/m

3 day

1

2

3

4

5

6

7

Toluene

MIBK

MEK

Styrene


- Biofilter response after Backwashing & Non-use periods: Styrene, MEK


• Results – Styrene biofilter response

Backwashing

0 200 400 600 4000 5000 6000

Styr

ene

Rem

oval

, %

20

40

60

80

100

Starvation

Time after the restart-up, min

0 200 400 600 4000 5000 6000

Styr

ene

Rem

oval

, %

0

20

40

60

80

100

Stagnant

Time after the restart-up , min

0 200 400 600 4000 5000 60000

20

40

60

80

100

0.64 kg COD/m3day1.27 kg COD/m3day3.17 kg COD/m3day

• Results – MEK biofilter response

I, 0.70 kg COD/m3dayII, 1.41 kg COD/m3 dayIII, 3.52 kg COD/m3 dayIV, 7.04 kg COD/m3 day

Starvation

Time after the restart-up, min

0 200 400 600 2000 4000 6000

Rem

oval

Eff

icie

ncy,

%

70

80

90

100

Backwashing

0 200 400 600 2000 4000 6000

Rem

oval

Eff

icie

ncy,

%

70

80

90

100

Stagnant

Time after the restart-up, min0 200 400 600 2000 4000 6000

0

70

80

90

100

0.7 kgCOD/ m3day1.41 kgCOD/m3day3.52 kgCOD/m3day7.04 kgCOD/m3day




• Results – Biomass distribution

Bed depth, L/Lo

0.0 0.2 0.4 0.6 0.8 1.0

Tot

al c

arbo

hydr

ates

mg/

g V

S

0

10

20

30

40

Bed depth, L/Lo

0.0 0.2 0.4 0.6 0.8 1.0

Pro

tein

s m

g/g

VS

0

1

2

3

40.0 0.2 0.4 0.6 0.8 1.0

Tot

al b

iom

ass

mg

VS/

g m

edia

0

20

30

40

After 7-day OperationAfter BackwashingAfter Starvation

Liquid & gas flowSubstrate: Toluene3.52 kgCOD/m3day




-

• Conclusion and Summary

1.1. Up to the critical VOC loading rate, the backwashing was effectiUp to the critical VOC loading rate, the backwashing was effective ve biomass control to attain consistently high removal performance.biomass control to attain consistently high removal performance.

2.2. NonNon--use periods can be considered as another means of biomass use periods can be considered as another means of biomass control at lower VOC loading rate. control at lower VOC loading rate.

3.3. ReacclimationReacclimation was a critical factor in was a critical factor in biofilterbiofilter peformancepeformance. . After nonAfter non--use periods, the active biomass affects use periods, the active biomass affects biofilterbiofilter response.response.

Experimental findings supported the handling limitation of Experimental findings supported the handling limitation of performance of the current performance of the current biofiltrationbiofiltration systemsystem


4.4. BiofilterBiofilter performance linked with performance linked with VOCsVOCs removal and removal and biomass growth depended on the physicochemical properties biomass growth depended on the physicochemical properties of of VOCsVOCs..

5. 5. BiofilterBiofilter performance was affected by microbial activity and performance was affected by microbial activity and biomass distribution.biomass distribution.

Experimental findings supported the handling limitation of Experimental findings supported the handling limitation of performance of the current performance of the current biofiltrationbiofiltration systemsystem

• Objectives

• Specific Objectives

To development of 2To development of 2--bed adsorption process for dampening bed adsorption process for dampening contaminant fluctuations contaminant fluctuations

•• Determine the adsorption isotherms of Determine the adsorption isotherms of VOCsVOCs of concernof concern•• Design and evaluate a 2Design and evaluate a 2--fixed bed adsorption unitfixed bed adsorption unit

Adsorption Isotherm


•• AdsorbateAdsorbate: : Toluene, MEK, MIBK

•• Adsorbent: Adsorbent: BPL-Bituminous based

OVC-Coconut based

•• Method: Method: Simple constant volume methodSimple constant volume method

Adsorption Isotherm

• Simple Constant Volume Method

• Using “Gas sample bag”, a 10-L Tedlar gas sample bag

• Using “Calibrated 6-L canister”for provide 6-L air into bags

Adsorption Isotherm

••

Adsorption Isotherm

• Results: Single solute Isotherm

•• MEK Adsorption on OVCMEK Adsorption on OVC

Adsorption Isotherm

ln Ce , mmol/m3

-1 0 1 2 3

ln q

e , m

mol

/g

-0.4

0.0

0.4

0.8

1.2

Regression line (r2=0.968)99% confidence intervals

Ini.Conc.=14.54 mmol/m3




•• Comparison of activated carbon adsorption capacityComparison of activated carbon adsorption capacity

Adsorption Isotherm


Ce, mmol/m3

10-2 10-1 100 101 102

q e (B

PL

/OV

C)

0

1

2

3

TolueneMEKMIBK

* Adsorbent Pore size distribution

* AdsorbateInteraction potentials

Adsorption Isotherm

• Results: Ternary Isotherm- Adsorbent: BPL- Adsorbate: Toluene, MEK, MIBK- Method: simple constant volume method- Simulation: IAST

Adsorption Isotherm

• Results: Ternary Isothermq e,

mm

ol/g

10-2

10-1

100

101

102

Toluene (Co = 5.48 mmol/m3, TRE (%) = 8.9)MEK (Co = 2.56 mmol/m3, TRE (%) = 26.9)MIBK (Co = 0.84 mmol/m3, TRE (%) = 24.5)

Ce, mmol/m3

10-3 10-2 10-1 100 101

q e, m

mol

/g

10-2

10-1

100

101

102

Toluene (Co = 2.9 mmol/m3, TRE (%) = 20.3)MEK (Co = 3.1 mmol/m3, TRE (%) = 8.3)MIBK (Co = 2.9 mmol/m3, TRE (%) = 23.6)

(a) Combination 1

(b) Combination 2


1.1. For single solute adsorption, the pore size distribution ofFor single solute adsorption, the pore size distribution ofadsorbents was found to affect their adsorption capacities; adsorbents was found to affect their adsorption capacities; its effect was dependents on the solute concentration.its effect was dependents on the solute concentration.

2. The ideal adsorbed solution theory (IAST) was found to 2. The ideal adsorbed solution theory (IAST) was found to accurately predicts the ternary adsorption isotherms.accurately predicts the ternary adsorption isotherms.

Single and ternary adsorption isotherms were successfully Single and ternary adsorption isotherms were successfully determined by employing a simple constant volume method determined by employing a simple constant volume method

Adsorption Isotherm

2-Bed Adsorption

• Concept

2-Bed Adsorption

•• Conceptually simple process to PSAConceptually simple process to PSA

•• PSA (Pressure Swing Adsorption) : PSA (Pressure Swing Adsorption) :

→→ A technology for separation and purification for gas mixturesA technology for separation and purification for gas mixtures

→→ 4 Steps for operational function4 Steps for operational function

Feeding (Adsorption)

Depressurization

Purging (desorption)

Repressurization

Regeneration

• Concept

2-Bed Adsorption

•• Hypothetically, if adsorption rate is equal to its Hypothetically, if adsorption rate is equal to its desorptiondesorption rate rate

→→ Operational function is simplified to a Operational function is simplified to a 22--stepstep

Feeding (Adsorption)

Purging (desorption)

Regeneration

• Concept

2-Bed Adsorption

•• Driving force for Driving force for desorptiondesorption: decrease in contaminant gas pressure: decrease in contaminant gas pressure

→→ Each bed will not be fully saturated with Each bed will not be fully saturated with adsorbateadsorbate

Clockwise

A

Waste GasGas to biofilter

BA

CounterclockwiseWaste Gas Gas to biofilter

A B

• Concept

2-Bed Adsorption

Will serve asWill serve as

•• Polishing unit during the initial acclimation period of the Polishing unit during the initial acclimation period of the biofilterbiofilter

•• Buffer unit in load fluctuation Buffer unit in load fluctuation

•• Feeding source without any feeding phase during nonFeeding source without any feeding phase during non--use periodsuse periods


2-Bed Adsorption

•• 2 Beds 2 Beds

•• Dimension : 2.5 cm (D) Dimension : 2.5 cm (D) ×× 20 cm (L)20 cm (L)

•• Duration of one cycle : 8 hoursDuration of one cycle : 8 hours

•• EBRT: 5.6 sec (2.2 L/min)EBRT: 5.6 sec (2.2 L/min)

•• AdsorbateAdsorbate : Toluene: Toluene

•• Adsorbent : GAC (BPL 6 Adsorbent : GAC (BPL 6 ×× 16)16)

* Design

• Results

2-Bed Adsorption

• Results

2-Bed Adsorption

• Efflunet response to cyclic operation and non-cyclic operation

Sequential Time, hrs0 8 16 24 32 40 48 482 484 486 488

Eff

luen

t C

once

ntra

tion

, ppm

v

0

100

200

300

Cyclic operation Non-cyclic operationTime, hrs

0 1 2 3

Inle

t, p

pmv

200

400

Critical inlet Conc.(250 ppmv) to biofilter

• Conclusion

2-Bed Adsorption

• The adsorption system consisted of two fixed beds which arealternately pressurized and depressurized was simply achieved.

• The operating adsorption and desorption cycles for the unit yielded constant loading conditions that can be treated effectively in the biofiltration

• Objectives

To evaluate the performance of the integrated treatment scheme To evaluate the performance of the integrated treatment scheme of a of a biofilterbiofilter preceded by a 2preceded by a 2--fixed bed adsorption unit fixed bed adsorption unit

Air

1. Air cleaner2. Mass flow controller3. Syringe pump4. Equalizing tank5. Flow meter6. 2-bed adsorber7. 4-way solenoid valve8. Supplemental air valve9. Biofilter

3

4

5

6

7

8

9

12

9


•• Targeted VOC: Targeted VOC: Toluene

•• Feeding condition: Feeding condition: Square wave change of inlet concentration- Base = 200 ppmv- Peak = 400 ppmv (15 mins / hour)- Average conc. : 250 ppmv- Average load. : 3.5 kg COD/m3·day

Time, min0 60 120 180

Inle

t C

onc. CH

CL

• Results: Toluene removal performance

• Results: Toluene removal performance

a) Integrated unit (2-bed adsorption + biofilter)

b) Control unit (biofilter)

1 10 100 1000

Eff

luen

t, p

pmv

1

10

100

Rem

oval

, %

0

20

40

60

80

100

Sequential Time, hrs1 10 100 1000

Eff

luen

t, p

pmv

1

10

100

Rem

oval

, %

0

20

40

60

80

100

Effluent concentrationRemoval efficiency

Detection limit (0.5 ppmv)

Sequential time, hrs

1017 1018 1019 1020 1021 1022 1023 1024

Eff

luen

t C

once

ntra

tion

, ppm

v

0.1

1

10

100

1000Control unitIntegrated UnitInlet Concentration

Day 42

• Results: Effluent performance after Non-use period

• Results: Effluent performance after Non-use period

Sequential time after non-use, hrs

0.1 1 10 100

Eff

luen

t, pp

mv

1

10

100

1000Control unit Integrated unit

2 days of non-use7 days of non-use

2 days of non-use 7 days of non-useDetection limit (0.5 ppmv)

• Results: Further Application


44--different feeding conditiondifferent feeding condition

•• 88--hr average effluenthr average effluent

•• 11stst order kinetic constantsorder kinetic constants : Estimate of biological activity: Estimate of biological activity


Time, min

0 60 120 180

Inle

t C

onc.

, ppm

v

0

200

400

600

800

a)8a)8--hr average effluent b) Reaction rate constanthr average effluent b) Reaction rate constant

Feeding conditionA B C D

Rat

e co

nsta

nt, s

ec-1

0.00

0.01

0.02

0.03


Eff

luen

t, m

g/m

3

0

100

200

300

Integrated unitControl unit Control unit Peak

Base

Integrated unitPeakBase

Feeding Condition

• Type A : 46.9 g/m3·hr




Rat

e co

nsta

nt, s

ec-1

0.00

0.01

0.02

0.03


Eff

luen

t, m

g/m

3

0

100

200

300


Base


Feeding Condition

• Type B : 46.9 g/m3·hr(High Peak)

Time, min

0 60 120 180

Inle

t C

onc.

, ppm

v

0

200

400

600

800




Rat

e co

nsta

nt, s

ec-1

0.00

0.01

0.02

0.03


Eff

luen

t, m

g/m

3

0

100

200

300


Base


Feeding Condition

• Type C : 56.3 g/m3·hr(Frequent Peak)

Time, min

0 60 120 180

Inle

t C

onc.

, ppm

v

0

200

400

600

800




Rat

e co

nsta

nt, s

ec-1

0.00

0.01

0.02

0.03


Eff

luen

t, m

g/m

3

0

100

200

300


Base


Feeding Condition

• Type D : 65.9 g/m3·hr(High & Frequent Peak)

Time, min

0 60 120 180

Inle

t C

onc.

, ppm

v

0

200

400

600

800

• Results: Comparison of reactor volume

Reactor volume Reactor volume of a single of a single biofilterbiofilter to achieve the same treatment goalto achieve the same treatment goalas in the integrated systemas in the integrated system


Reactor volume Reactor volume of a single of a single biofilterbiofilter to achieve the same treatment goalto achieve the same treatment goalas in the integrated systemas in the integrated system

Feeding Condition Type A Type B Type C Type D

Peak concentration (Ci,p), ppmv

(g/m3)

400

(1.53)

700

(2.68)

400

(1.53)

600

(2.30)

Biofilter bed volume required (V), m3 ** 0.00435 0.00761 0.00435 0.00653

V / Vintegrated ** 1.5 2.6 1.5 2.2

* Volume of the integrated unit = 0.00293 m* Volume of the integrated unit = 0.00293 m33

• Conclusion

The net effect of the 2The net effect of the 2--bed adsorption was VOC concentration bed adsorption was VOC concentration stabilization that makes it amenable for effective stable biodstabilization that makes it amenable for effective stable biodegradationegradation

1. The 21. The 2--step cycle in the adsorption unit successfully performedstep cycle in the adsorption unit successfully performedparticular functions asparticular functions as

•• A polishing unit to abate the initial acclimation for the A polishing unit to abate the initial acclimation for the biofilterbiofilter;;•• A buffering unit to mitigate the A buffering unit to mitigate the biofilterbiofilter performance; performance; •• A feeding source for the A feeding source for the biofilterbiofilter without any feeding phase without any feeding phase

2. Details of the reactor volume suggest that capital expense ca2. Details of the reactor volume suggest that capital expense can be n be minimized by achieving a careful design and operation of minimized by achieving a careful design and operation of the integrated treatment scheme.the integrated treatment scheme.

•• Dr. George A. Dr. George A. SorialSorial

•• Dr. Dr. MakramMakram T. T. SuidanSuidan

•• Dr. Dr. DionysiosDionysios D. D. DionysiouDionysiou

•• Dr. Albert D. Dr. Albert D. VenosaVenosa

•• Mr. Mr. ZhangliZhangli CaiCai

•• National Science Foundation (NSF)National Science Foundation (NSF)

Dissertation Defense for the Degree of Ph.D.

Documents

Dissertation Defense for the Degree of Ph.D. January 19, 2006 …sorialga/Biofilter Website/s... · Dissertation Defense for the Degree of Ph.D. January 19, 2006 Daekeun Kim • VOCs