Reduction of Green Sand Emissions by a Minimum of 25% - A Case Study

22nd EH&S Conference

August 2010

Nashville Tennessee

Vision of the Future

Discussion Points

� Seacoal reduction and/or elimination

– Improved economics

– Reduced emission characteristics

Core/Mold Make Organic

2

%

Melting Organic

4

% Melting Metallic

3%

PCS Metallic

1%

PCS Organic

90

% PCS - 90%

Melting Metallics 3%

PCS Metallic 1%

Core/Mold Making Organics 2%

Melting Organic 4%

CERP Data

600 F Heat Zone: Sodium Bentonite and

Fireclay unaffected Calcium Bentonite

partially calcined, carbons remain.

Mold Metal Interface: All bonding materials altered.

Clays Calcined, Carbons converted to Ash.

1200 F Heat Zone: Sodium Bentonite and

Fireclay partially calcined Calcium Bentonite

Calcined, Carbons converted to “Fixed

Carbons” (coking materials).

Molding sand

properties and

materials not

altered in the

remaining

prepared sand.

Cross Section of an Iron Mold

Sources of Emissions

Casting

Molding sand

Core

Emissions from core

binders and additives

Emissions from organic

moulding sand additives

Test Apparatus at University of Freiburg

Smoke Comparison

Preblend with

Processed Carbon

Smoke Elimination in Foundry

CERP Test Results

Analyte Name

Reference

(5% Seacoal

Mix)

Average

No Seacoal

(with

Processed

Carbon)

Average

Percent

Change from

Test

Reference

Emission Indicators

TGOC as Propane 3.3541 0.7720 -77

HC as Hexane 0.4015 0.1335 -67

Sum of Target Organic

Analytes 0.4271 0.0767 -82

Sum of Target Organic

HAPs 0.3390 0.0642 -81

Sum of Target POMs 0.0197 0.0014 -93

Foundry LOI Data

LOI (1800°F)

0

1

2

3

4

5

6

7

8

1/4

/20

05

1/1

8/2

00

5

2/1

/20

05

2/1

5/2

00

5

3/1

/20

05

3/1

5/2

00

5

3/2

9/2

00

5

4/1

2/2

00

5

4/2

6/2

00

5

5/1

0/2

00

5

5/2

4/2

00

5

6/7

/20

05

6/2

1/2

00

5

7/5

/20

05

7/1

9/2

00

5

8/2

/20

05

8/1

6/2

00

5

8/3

0/2

00

5

9/1

3/2

00

5

9/2

7/2

00

5

10

/11

/20

05

10

/25

/20

05

11

/8/2

00

5

11

/22

/20

05

12

/6/2

00

5

12

/20

/20

05

1/3

/20

06

1/1

7/2

00

6

1/3

1/2

00

6

2/1

4/2

00

6

2/2

8/2

00

6

3/1

4/2

00

6

3/2

8/2

00

6

4/1

1/2

00

6

4/2

5/2

00

6

5/9

/20

06

5/2

3/2

00

6

6/6

/20

06

Date

% LOI

LOI

Linear (LOI)

Foundry Test Data

LOI (I3 Line): Daily Sand Tests

1.0

2.0

3.0

11/2/2009

11/5/2009

11/10/2009

11/16/2009

11/20/2009

11/30/2009

12/4/2009

12/9/2009

12/14/2009

12/18/2009

1/4/2010

1/7/2010

1/11/2010

1/15/2010

1/20/2010

1/26/2010

1/31/2010

2/4/2010

2/17/2010

2/20/2010

2/23/2010

2/25/2010

3/1/2010

3/4/2010

3/9/2010

3/12/2010

3/18/2010

3/29/2010

4/5/2010

4/8/2010

4/14/2010

1800 F LOI

Introduction of Seacoal Elimination

6.831.0525.74206.5525.20-Average 2007

5.740.5222.95206.5725.04191.702007

7.921.5828.52206.5325.35189.322007

3.400.5215.43128.6520.92-Average 2008

3.140.5214.13116.1520.93191.132008

3.660.5216.73141.1520.91191.292008

[dm3/kg][g]

XyleneEthylobenzeneTolueneBenzene

Emission of gases [mg/kg green sand]

Volume of gasesWeight of

sampleSample

Reduction in Gas Volume in the Mold

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

0 10 20 30 40 50 60 70

Time, s

Gas evolution rate (cm

3/gs)

CO-H1

CO-H2

Coking Characteristic of Seacoal

SOURCE: Hill and Griffith Company

Expansion Defect

S R

1

2

3

R = Rat Tail

S = Scab SOURCE: AFS International Atlas of Casting Defects

Examples of Castings

Summary

� Reducing and/or eliminating seacoal will reduce

the material cost in green sand. (Economic

Advantage)

� Seacoal reduction or elimination will reduce the

emission characteristics of green sand.

(Environmental Advantage)

� Foundries can make good castings with seacoal

reduction or elimination techniques.

Questions and Answers