Evaluation of Biological and Chemical Methods of Hydrogen Sulfide Containment

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Evaluation of Biological and Chemical Methods of
Hydrogen Sulfide Containment Joaquin
Bestard Neisy Carrasco Havala Taylor Vashaun
Prabhudial
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What is Hydrogen Sulfide?
H2S Objective Determine what hydrogen
sulfide treatment system is most suited to
certain applications.

• Chemical Properties
• Applications
• Environmental Standards
• Human Effects

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Biofiltration

• Uses a reactor column packed with natural or
  synthetic media that contains a microbial
  population
• Waste gas stream passes through the reactor and
  remains there for a certain residence time
• During residence time microorganisms oxidize
  hydrogen sulfide
• Biofilters harness natural abilities of
  microorganisms to biochemically degrade odorous
  compounds into environmentally harmless end
  products

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Biological Treatment Example
Specific treatment (bio)
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HD Q-PAC Biofilter Material
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Advantages and Disadvantages of Biofilters

• Advantages
• Uses a process that occurs naturally
• Occurs at ambient conditions
• Environmentally friendly
• Cuts down consumable use
• Tolerates fluctuating hydrogen sulfide
  concentrations
• Removal as high as 99.5

• Disadvantages
• Variable removal (95 removal with HD Q-PAC)
• constant monitoring
• moisture content must be adjusted
• pH sensitive
• sensitive to air flow

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Chemical Treatment
Furnace Rxn (1) H2S 3/4 O2 ? SO2
H2O Catalytic Reactor Rxn (2) 2H2S SO2 ? 2H2O
3S0
air
Overall Reaction H2S ½ O2 ? S H2O
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Advantages and Disadvantages of Chemical
Treatments

• Advantages
• Functions well for large gas streams
• Economical for large gas streams with hydrogen
  sulfide content
• Reliable
• Solvent/catalyst reused
• Can achieve 99.2 removal of hydrogen sulfide
• Produces high purity sulfur

• Disadvantages
• Does not function for aerobic conditions
• Does not work if any combustible species are
  present
• Strict regulation of air required for furnace
• Energy input required for absorption, furnace,
  condenser, etc.
• Tail gas incinerators emit SO3/SO2 (acid rain
  precursor)

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Conclusions

• Choice of treatment type is dependent on industry
  
• Biological treatment is good for
• water treatment plants
• low relative concentrations of hydrogen sulfide
• space restricted areas
• Chemical treatment good for
• industries that want/use sulfur
• high, constant concentration of hydrogen sulfide