Desulfurization Technologies for Landfill Gas

							Desulfurization Technologies
      for Landfill Gas
Choices for Desulfurization Technologies
Depend Largely on Daily Sulfur Loads
  Very low levels of H2S—less than about 50 pounds sulfur (S)/day:
    Liquid scavenger: The ELIMINATOR™

  Low levels of H2S—about 50 to 300 pounds S/day
   Solid media technology: Sulfur-Rite®

  Medium levels of H2S—about 300 pounds to 20 long tons S/day
    Iron redox technology: LO-CAT® or MINI-CAT™

  High levels of H2S—Greater than about 20 long tons S/day
    Claus technology: petro-chemical industry, not LFG
Determination of Daily Sulfur Production Rate



                          MMscfd              ppm H2S
PPD S             
                                            11.83
Where:
PPDS = Pounds per day of sulfur generated
MMscfd = Gas rate (in million scfd)
ppmH2S = H2S Concentration (in ppm)
SELECTING THE RIGHT TECHNOLOGY
Desulfurization Unit Select-A-Guide


 Technology Name     When Normally Used   Relative Capital Cost   Operating Cost


 Liquid Scavenger:                                                $4.00 to $10.00
                        < 50 lbs./day        Extremely Low
 The ELIMINATOR™                                                  per pound of S

   Solid Media:                                                   $3.00 to $6.00
                       50–300 lbs./day            Low
    Sulfur Rite®                                                  per pound of S
    Iron Redox:
                         300 lbs to                               $0.20 to $0.40
     LO-CAT® or                              Medium to High
                         20 tons/day                              per pound of S
    MINI-CAT™
Liquid Scavenger Technologies

  Very low sulfur recovery: less than about 50 pounds/day
    Large waste product stream (liquid) requiring disposal
  Technologies include:
    The ELIMINATOR™
      • Marketed by Gas Technology Products
      • Uses amine resins
    Others
      • Use triazine-based compounds containing formaldehyde
  Application:
      • Liquid spray into the gas or
      • Bubble tower
Solid Scavenger Technologies

  Low sulfur recovery: about 50–300 pounds/day
   Large waste product stream (solid) requiring disposal
  Use iron and/or zinc oxide-based compounds that are an
  improvement over old ―iron sponge‖ technology
  Technologies
   Sulfur Rite®
      • Marketed by Gas Technology Products
  Application: Batch treatment using packed tower
Iron Redox Technology

  Medium sulfur recovery: about 300 pounds to 15 long tons S/day
    Small product stream: Solid sulfur that can be used in agricultural
     applications
  Most appropriate for larger LFG applications
    LFG projects too small for Claus process
  Iron Redox Technologies
    LO-CAT®
       • Marketed by Gas Technology Products
    MINI-CAT®
       • Marketed by Gas Technology Products
       • Same technology as LO-CAT: Modular FRP design with lower CAPEX and smaller
         footprint for LFG applications