State of Practice for SNCR

1
State of Practice for SNCR

• Robert J. Schreiber, Jr.
  Schreiber, Yonley Associates

Research Conducted for the Portland Cement
Association
2
Project Tasks

• Task 1 Literature Search
• Task 2 Terminology / Methodology
• Task 3 Identification of SNCR Reagents
• Task 4 Regulatory Consideration and
  Applicability of SNCR
• Task 5 Current State of Practice for SNCR Use
• Task 6 Current State of Practice for SNCR
  Installation
• Task 7 Experience in Other Industries

3
(No Transcript)
4
Task 1 Literature Search

• PCA provided summary
• Search terms
• SNCR or Selective Non-Catalytic Reduction and
• Ammonia / Urea / Reagent and
• Oxide / Emission / Pollutant
• 2000 2007 publish date
• SYA requested specific titles

5
Task 2 Terminology / Methodology

• Terminology
• NOx Formation
• Thermal NOx
• Prompt NOx
• Fuel NOx
• Feed NOx
• Amidogen ion (NH2 amine radical)
• Reducing Reagents
• Ammonia
• Anhydrous
• Aqueous
• Urea
• Biosolids

6
Task 2 Terminology / Methodology

• Terminology
• Normalized Stoichiometric Ratio
• Molar ratio
• Ammonia
• Urea
• Reagent Utilization
• Ammonia Slip
• SNCR Effectiveness
• Percent NOx reduction

7
Task 3 Identification of SNCR Reagents

• Reagents
• Primary reagents
• Ammonia
• Anhydrous (RMP, PSM, Homeland Security)
• Aqueous
• Urea
• Other reagents
• Cyanuric Acid (C3H3N3O3)
• Biosolids
• Processed Photographic water

8
Task 3 Identification of SNCR Reagents

• Reagents
• Primary reagents
• Suppliers
• Costs
• Special considerations
• PSM
• RMP
• Homeland Security

9
Task 4 Regulatory Considerations

• Clean Air Act
• NOx NAAQS
• Clear Skies Legislation
• Clean Air Interstate Rule (CAIR)
• Ozone Transport Commission
• South Coast Air Quality Management District

10
Other Regulatory Considerations

• Regional Haze (BART)
• NOx affects PM2.5
• PM2.5 non-attainment areas
• Regional Planning Organizations

11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
(No Transcript)
15
Task 4 Regulatory Considerations

• State Specific Reductions
• Department of Homeland Security
• Aqua ammonia 20 or greater
• Anhydrous ammonia

16
Task 5 Current SNCR Practice

• Operating Issues
• Temperature
• Where to inject the reagent
• High turbulence
• Sufficient residence time

17
Task 5 Current SNCR Practice

• Operating Issues
• Reagent handling
• Ammonia is a toxic chemical
• RMP
• PSM
• Urea solutions are more viscous
• Delivery system must allow for this

18
Task 5 Current SNCR Practice

• Operating Issues
• Ammonia slip
• Ammonia emissions
• Odors
• Inefficient use of reagent
• Impact on synthetic gypsum from scrubber
• Ammonium salt formation

19
SNCR

• Equipment Required
• Reagent tank
• Distribution system
• Control system
• CEMS for NOx ammonia required to determine
  optimum ammonia injection rate to maximum NOx
  control minimize ammonia slip
• If urea used, water treatment system heat
  traced storage piping required

20
Reagent Tank
21
(No Transcript)
22
Reagent Injection System
23
SNCR

• Until Recently, SNCR Limited to PH or PH/PC Kilns
• SNCR Used Extensively in Europe for NOx Control
• One Plant in Europe Using SNCR on Long Wet Kilns
• Two plants in U.S. Tested SNCR on Long Wet Kiln
  Systems Expect to Use SNCR to Comply with New
  Ozone SIP Requirements

24
SNCR in Wet Kilns
Location 2 1100C
Urea injector
25
(No Transcript)
26
(No Transcript)
27
Task 6 Current SNCR Installations
28
Task 6 Current SNCR Installations
29
Task 6 Current SNCR Installations
30
RACT / BACT / LAER Database

• The RBLC database has identified the following
  SNCR applications
• Branford Cement (Suwanee)
• Permit limit of 1.95 lb/ton
• American Cement
• Permit limit of 1.95 lb/ton
• Sumter/Center Hill Cement
• Permit limit of 1.95 lb/ton
• Brooksville Cement Plant (Florida Crushed Rock)
• Permit limit of 2.4 lb/ton at startup (180 days)
  then limit of 1.95 lb/ton
• Thompson Baker Cement Plant (Florida Rock)
• Permit limit of 2.45 lb/ton (180 days) then limit
  of 1.95 lb/ton
• Lehigh Mason City
• Permit limit of 2.85 lb/ton

31
SNCR Controls in Europe (Cement) (2005)

• Country Number of SNCR Plants
• Denmark 1 (by end of 2005)
• Germany gt 30
• France 14 (by end of 2005)
• Great Britain 1 (by end of 2005)
• Italy lt 10
• Austria 5
• Sweden 3
• Switzerland 4
• Spain 1

32
Task 7 Current SNCR Use in Other Industries

• Electric Utility Industry
• Exxon patented ammonia SNCR in 1975
• EPRI patented urea SNCR in 1980
• Current trend is multi-pollutant strategies
• Economics
• To meet more stringent requirements

33
SNCR Cost Considerations

• Anhydrous Ammonia
• Delivered cost is approximately 850 per ton
• Truck contains 22 tons
• Aqua Ammonia
• Delivered cost is approximately 950 per ton
  (anhydrous basis)
• Truck contains 4.5 tons (anhydrous basis)
• Urea
• Delivered cost is approximately 250 per ton for
  a 50 solution

34
Reagent Cost Example

• Assumptions
• Uncontrolled NOx emissions 1000 tpy
• NOx is 90 NO, 10 NO2
• Reduction 40
• Total NOx Reduced 400 tons
• Ammonia used as reagent
• Cost of 19 ammonia 950/ton anhydrous basis
• Cost of anhydrous ammonia 850/ton
• Cost of 50 urea 250/ton
• NSR 1.0

35
Reagent Cost Example
36
SNCR Cost Considerations

• Ammonia costs have increased in the past year.
• 80 of US ammonia usage is agricultural
• 40 of US ammonia usage is for corn
• Ammonia demand increase is driving cost
• With an ammonia system, cost analysis must
  include RMP, PSM compliance costs
• Ammonia increases provided by AirGas

37
SNCR Cost Analysis (cont.)

• Operating costs
• Reagent 500,000
• Utilities 235,000
• Electricity
• Labor and Materials 99,500
• Overhead 151,000
• Taxes
• Administration
• Insurance
• Total Operating Cost 1 MM/YR

38
Reagent Cost Effectiveness

• Reagent costs have increased
• Cost Effectiveness in 2007 (reagent /ton NOx
  removed)
• Anhydrous 808/ton
• 20 Aqua 921/ton
• Urea 826/ton
• Cost effectiveness in 2008 (reagent /ton NOx
  removed)
• Anhydrous 1,143/ton
• 20 Aqua 1,227/ton
• Urea 1,290/ton

39
Summary

• SNCR is a mature technology
• Application is more easily applied to PH/PC
  systems
• NOx reductions of 30-60 typical
• Consideration must be given to
• Temperature
• Turbulence
• Residence Time
• NSR

40
Summary

• SNCR is a mature technology
• Potential adverse affects
• Ammonia slip
• Odors
• Formation of ammonium salts
• Detached plume
• NOx may increase if the temperature is too high