Transcript TT35 Meeting EPA Compliance with DynaWave

MECS INC.
940-1
Meeting EPA Consent Decree
Compliance with DynaWave
Scrubbing
Presented by
Larry Paschke.
940-2
Background/History

Headquarters - St. Louis, Missouri

Global Business

250 Employees

75 Years - Monsanto/MECS designed
and constructed over 800 chemical and
cogeneration projects

1969: MECS formed

2005, Management Buyout from Monsanto
and MECS Inc. formed.
940-3
MECS Inc. Capabilities

Design and supply air pollution control
products
– DynaWave Scrubbers
– Brink Mist Eliminators

Design and build sulfuric acid plants

Supply proprietary products to the sulfuric
acid industry
– Specialty alloys
– Catalyst
– Tower internals
940-4
Important Issues To Be Addressed

Performance
– SO2 Removal
– SO3 Removal
– PM Removal
– Other Consideration/Effluent Treatment

Applications
– FCCs
– SRUs
940-5
SO2
Removal
940-6
SO2 Removal

Mass Transfer
– Gas/Liquid Contact Mechanism
– Total L/G (gpm / 1000 acfm)
– Reagent Kinetics

Caustic

Soda Ash

Lime

Limestone
940-7
DynaWave Scrubber
940-8
SO2 Mass Transfer / Reagent
100
98
SO2 %
Removal
99
99.5
98.5
97
96
96
95
94
92
80 L/G
90
Caustic
40 L/G
Soda Ash
940-9
Limestone
Reagent Overview
Reagent
Reactivity
Caustic
Most reactive
Highest cost
Soda Ash
Very Reactive
Moderate
Cost
Magnesium
Hydroxide
Moderately
Reactive
Moderate
Cost
Lime
Less
Reactive
Lower Cost
Limestone
Least
Reactive
Lowest Cost
940-10
Operating
Cost
Reagent Costs
Required
Reagent
Lb/Lb of
SO2
Relative
Reagent
Cost NaOH
=1
Treatment
Cost/lb of
SO2
Caustic (NaOH)
1.25
1.0
1.25
Soda Ash (Na2CO3)
1.65
0.26
0.43
Mag Oxide (Mg(OH)2)
0.91
0.16
0.146
Lime (Ca(OH)2)
1.16
0.125
0.145
Limestone (CaCO3)
1.56
0.025
0.04
940-11
Reagent Reaction Products

Caustic
Soluble Salt

Soda Ash
Soluble Salt

Trona
Soluble Salt

Lime
Insoluble Solid

Limestone
Insoluble Solid
940-12
Navajo Test Data
Pilot Plant
Run 1
Run 2
Run 3
Ave
SO2 Inlet (lb/h)
1.87
1.80
1.90
1.86
SO2 Outlet (lb/h)
0.02
0.01
0.02
0.017
Outlet ppmvd 0% O2
5.11
3.87
5.57
4.85
SO2 % Removal
98.9
99.4
98.9
99.1
Full Scale Installation
CEM measures < 1 ppmvd 0% O2 corrected
940-13
Particulate
Removal
940-14
Particulate Matter

Size Distribution of catalyst fines
(PSD)

Gas side pressure drop used by
scrubber
Smaller
particles require more pressure drop
940-15
Particulate Removal
Typical FCC PSD
< 0.1 microns
0.1 Wt%
< 0.3 microns
4%
< 1.0 microns
35%
< 1.5 microns
54%
< 3.0 microns
75%
> 20 microns
6%
940-16
% Removal
Example: 25” wc required for 90%
particulate removal
100
90
80
70
60
50
40
30
20
10
0
0
10
20
30
Pressure Drop (in wc)
940-17
40
50
Navajo Test Data
Pilot Plant
Run 1
Run 2
Run 3
Ave
PM Inlet (lb/h)
1.15
2.39
0.78
1.44
PM Outlet (lb/h)
0.01
0.01
0.01
0.01
99.1
99.6
98.7
99.1
PM % Removal
Full Scale Installation
Reduction of PM by 93%
940-18
SO3/Acid Mist
Removal
940-19
SO3 Removal Mechanism
(NOT the same as SO2)

Opacity
– Diffraction of light waves by
particles

Hydrolyzed to H2SO4 liquid droplets
– 0.4 micron size

Not absorbed, mechanical removal
Gas
side pressure drop required
940-20
Example: 40” wc gas pressure drop
required to remove 90% of SO3
100
90
SO3 % Removal
80
70
60
50
40
30
20
10
0
0
10
20
30
Gas Pressure Drop, in wc
940-21
40
50
60
Other
Considerations
Effluent Treatment
940-22
COD
Chemical Oxygen Demand

Measured as mg O2 / liter solution or
ppm

Convert sodium sulfite/bisulfite salts
to sulfate salts

Forced oxidation to sodium sulfate
– O2 to S ratio
– Residence time
– Air dispersion
940-23
COD
Chemical Oxygen Demand

Typical COD target range 50 to 200
ppm

Consider “pre-existing” COD in
makeup water

Two oxidation methods
– In-Situ
– Ex-Situ
940-24
DynaWave Scrubber
In-Situ Oxidation
940-25
Effluent Rate Requirements

Set by dissolved
solids concentration

Salt concentrations up to 20 wt%

Low effluent rate to waste water
treatment desirable
940-26
Effluent Rates
20%
% salts
15%
10%
5%
0
20
40
60
gpm
Assumes 1000 lb/h SO2 removed
940-27
80
100
Other Considerations
Materials of
Construction
940-28
Materials of Construction

Considerations
– Inlet temperature
– Wet / dry interface
– Chlorides
Alloy
Approx. Relative Cost
Chloride Limit ppmw*
316L
1.0
300
Duplex RA-2205
1.3
20,000
AL6XN
3.3
+30,000
Hastelloy C-276
6
+100,000
* By Rolled Alloys.
940-29
DynaWave Scrubber
Reaction zone:
AL6XN
Hastelloy
Duplex 2205
Vessel:
Duplex 2205
316L stainless
940-30
Sources of Chlorides
 Caustic
 Make-up
 FCC
Water
Off Gas
940-31
Monsanto DynaWave
Scrubber
940-32
On-Line Reliability

Minimal mechanical equipment

Withstands upset conditions– Large catalyst carryover to scrubber
– Abrasion/pluggage design
considerations

Large Reverse Jet nozzles
940-33
Monsanto Refinery
Experience
940-34
Navajo Installation
30,000 BPD FCC
940-35
DynaWave in SRU

Very cost competitive versus conventional
technology

Designed to meet
– 100 ppmvd SO2, corrected to 0% O2
– 100 mg/L COD
– Less than 10% opacity

Handles high sulfur loadings during off
ratio and SRU bypass cases
940-36
Conclusion

DynaWave Applications
– FCC, SRU, Calciner, S-Zorb

Compliance Help with
– Consent Decrees
– MACT II

Lower capital and operating costs

Proven Experience
940-37
Thank you.
940-38