RESULTS OF SEVERAL YEARS OPERATION OF A FUNNEL AND GATE SYSTEM WITH BIO REACTOR

AT A FORMER TAR FACTORY SITE

Christian Weingran (HIM GmbH, Biebesheim, Germany) Jörn Müller and Tobias Bartelsen (CDM Smith Consult GmbH, Alsbach, Germany)Andreas Tiehm and Axel Müller (Water Technology Center, Karlsruhe, Germany)

Hermann Schad (I.M.E.S. GmbH, Amtzell, Germany)

I.M.E.S.

Table of Contents

• Description of the Site

• Preliminary Tests, Design and Construction of the Pilot Gate

• Results of the Operation of the Bioreactor

• Next Steps

• Since 1989 HIM GmbH is responsible on behalf of the land Hesse for the remediation of contaminated sites in those cases, where responsible parties can not at all or not in time be charged with the cost for remediation.

• HIM-ASG in Hesse manages about 40 projects with a financial volume of approx. 15 - 17 m. €per year.

HIM GmbHDepartment Remediation of Contaminated Sites - HIM-ASG

Site Description

Area:25.000 m²

Contamination:Tar oil (partly in phase)

Aquifer:quaternary sand and gravel

Base of aquifer:6-8 m bgl

Depth to water level:2-3 mgroundwater flow

Barrage

Groundwater Flow

Former Tar Factory

Tar oil

Contamination in Groundwater

BTEX 8.000 µg/l

Benzene 3.000 µg/l

PAH2-16 400 µg/l

Naphthalene 5.600 µg/l

NSO-HET 1.500 µg/l

Benzofuran 700 µg/l

Benzothiophen 300 µg/l

Phenole 1.900 µg/l

Plume

Contamination

Contaminant Concentration Aerobic Degradation

Sorption on Activated Carbon

BTEX 8.000 µg/l ++ +

Other Aromatic Hydrocarbons

4.500 µg/l ++ ++

Naphthalene 5.600 µg/l ++ ++

3 ring PAH 400 µg/l ++ ++

4-6 ring PAH 5 µg/l +/- +++

Heterocyclic Compounds (HCY)

1.500 µg/l ++ +

Potential for Elimination of Contaminants

• Description of the Site

• Preliminary Tests, Design and Construction of the Pilot Gate

• Results of the Operation of the Bioreactor

• Next Steps

Preliminary Tests

Batch tests in the lab Column tests in the lab On-site column test

The system gets more complex and approaches on-site conditions.

• Which contaminants are degraded by the autochthonous micro-organisms?

• How long is the duration of the degradation?

• Which amounts of oxygen (delivered as H2O2) and nitrate are necessary?

• How do micro-organisms and toxicity develop during the degradation?

Benchmark Data for the Operation of the Pilot Gate

• Approx. 180 mg H2O2 / L of contaminated groundwater

• Stepwise and moderate increase of dose rate in the start phase

• Total residence time in the bioreactors: > 72 h

• Iron removal in front of the bioreactors

• As many dosing ports as possible for H2O2 injection

• Accessible dosing ports (development of free water zones)

• Avoiding gas clogging by O2 and other gases in the bioreactors

Technical Design of the Gate (Top View)

Technical Design of the Gate (Sectional View)

Construction Pit for the Gate

Inflow Area of the Gate

Construction of the Free Water Zones

1

2

3

Sampling Well

Dosing Station Free Water Zone

Bioreactors 1 to 3 (filled with fine gravel)

Top of the Gate and Surroundings

• Description of the Site

• Preliminary Tests, Design and Construction of the Pilot Gate

• Results of the Operation of the Bioreactor

• Next Steps

Flow Rate and Water Level

0

100

200

300

400

500

600

700

800

900

1000

94,40

94,60

94,80

95,00

95,20

95,40

95,60

2009-05 2009-09 2010-01 2010-05 2010-09 2011-01 2011-05 2011-09 2012-01 2012-05 2012-09

Flo

w R

ate

[l/h]W

ate

rlevel

[m N

N]

Waterlevel FWZ1 Waterlevel FWZ4

Waterlevel lamella separator Waterlevel GWM21

Flowrate

Degradation along the Reactor (January 2012)

0,01

0,10

1,00

10,00

100,00

1.000,00

10.000,00

Untreated Water Lamella Separator Bioreactor 1 Bioreaktor 2 Bioreactor 3

Co

ncen

trati

on

of

Co

nta

min

an

ts [

µg

/l] Benzene

BTEX

Naphthalene

PAH (2-16)

HCY

Alkyl-Phenole

Phenol-Index

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< L

OD

< LOD

0,01

0,10

1,00

10,00

100,00

1.000,00

10.000,00

Mar 2007 Aug 2008 Dec 2009 May 2011 Sep 2012

Co

ncen

trati

on

of

PA

H (

1-1

6)

[µg

/l]

Input

Lamella Separator

Bioreactor 1

Bioreactor 2

Bioreactor 3

Degradation of PAH

0

10

20

30

40

50

60

70

80

90

100

Co

nta

min

an

t -

Eli

min

ati

on

[%

]

Lamella separator

Bioreactor 3Bioreactor 1

Bioreactor 2

Elimination of Contaminants (Average)

2009 2012

0

10

20

30

40

50

60

70

80

90

100

Co

nta

min

an

t -

Eli

min

ati

on

[%

]

Lamella Separator

Bioreactor 3

Bioreactor 1

Bioreactor 2

Elimination Rates

Parameter Average 2011

January 2012

July 2012

Average 2012

Benzene 97,7 100,0 100,0 100,0

BTEX 97,9 100,0 100,0 100,0

Naphthalene 99,8 100,0 100,0 100,0

PAH w/o Naph. 97,3 100,0 100,0 100,0

HCY 96,3 99,9 100,0 100,0

Phenol-Index 87,6 100,0 100,0 100,0

Reduction of Toxicity (Average 2011)

*

Untreated Water

Lamella Separator

Bioreactor 1 Bioreactor 2 Bioreactor 3

Low

est

Ineffective D

ilution (

LID

)* [

-]

Mass Flow 2007 to 2012

0

5

10

15

20

25

30

35

40

45

50

55

March 2007 July 2008 December 2009 April 2011 September 2012

Mass F

low

[kg

]

BTEX Benzene

PAH (2-16) Naphthalene

HCY Phenol-Index

Development of Contaminants (Source)

0

1000

2000

3000

4000

5000

6000

7000

Benzene BTEX Naphthalene PAH (2-16) HCY

Co

ncen

trait

on

of

Co

nta

min

an

ts [

µg

/l]

2010 2011 2012

Development of Contaminants (Downstream)

0,01

0,10

1,00

10,00

100,00

Benzene BTEX Naphthalene PAH (2-16) HCY

Co

ncen

trati

on

of

Co

nta

min

an

ts [

µg

/l]

Sep 2010 Apr 2011 Sep 2011 Feb 2012 Apr 2012 Jul 2012 Oct 2012

Contamination Downstream

Monitoring and Operating

Monitoring Parameter Control Points Time Intervall

SAK254nm, Oxygen Input & Output Gate Monthly

Contaminants (PAH, HCY, BTEX, Phenol)

Input gate, Output BR1, Output Gate, Control Points Downstream

Quarterly

Inorganic Parameters (Fe, Nitrate, Nitrite, Ammonium, Phosphate)

Input Gate, Output BR1-BR3, Output Gate, Control Points Downstream

Semiannually

Operating Activities Responsibility Time Intervall

Maintenance (Pumps for Dosing 300 mg/l H2O2, Electrics, etc.)

Operator of the Facility Monthly

Groundwater Monitoring, Field Survey, Supervision of the Site

Engineering Consultant Monthly / Quarterly

• Construction 770,000 €

• Monitoring 50,000 €/a

• Operating 40,000 €/a

• Monitoring and operating cost will be reduced after the extension of the system and the demonstration of a permanent effective clean up.

Cost

• Description of the Site

• Preliminary Tests, Design and Construction of the Pilot Gate

• Results of the Operation of the Bioreactor

• Next Steps

∑ 650 l/h

Funnel Extension East

Groundwater Extraction

Groundwater Extraction

Tar Oil

Funnel Extension West

Extension of the Funnel and Gate System

• Full hydraulic containment of the site by extension of the funnels

• No need for a second gate

• Active groundwater-extraction

• Controll of groundwater-flow

• Stabilization of degradation processes

• No need for an activated carbon zone

• Establishing ENA processes downstream

Important Features

Thank you for your attention !

It was sponsored by the German Federal Government and the state of Hesse.

This projekt was part of RUBIN research network.