Volatile Organic Compounds Management Plan - PowerPoint by tai12886

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									                               Odor
• Has insignificant effects on the global or national
  environment
• Has major effects on the local environment
   – Nearest dwelling
   – Greatest source of nuisance complaints
       • Operations              % of nuisance complaints from odor
         Swine                               95
         Broiler                             75
         Layer                               66
         Beef feedlots                       50
   – Sources
       •   Animal buildings and lots
       •   Manure treatment and storage
       •   Land application
       •   Silage
       •   Feed processing
       •   Dead animal disposal
   – Difficult to define, quantify, and control
       • Odor composed of 331 compounds in manure
            – 30 compounds most common in swine manure
• Most objectionable compounds in manure
                                                         Odor threshold
___Class___       ___Compound___         ____Smell_____  ____ppm____     Substrate
Volatile fatty    Butyric acid          Rancid butter        .001        Carbohydrate
Acids            Isobutryic acid        Rancid butter          -         Protein
                  Caproic acid                  -              -         Carbohydrate
                  Isocaproic acid               -             -          Protein
                  Valeric acid          Putred fecal           -        Carbohydrate
                  Isovaleric acid       Stinky feet           -          Protein
                  Propionic acid        Intense vinegar     20.0        Carbohydrate
                  Phenylpropionic acid          -              -        Protein
                  Lauric acid                   -             -         Carbohydrate
                  Acetic acid           Vinegar               1.0       Carbohydrate
Ammonia and      Ammonia                Acrid               46.8        Protein
Amines           Amines
                    Putrescine         Rotting flesh              -     Protein
                    Cadaverine         Rotting flesh              -     Protein
                  Trimethyl amine              -               .00021   Protein
                  Trimethyl pyrazine           -                  -     Protein
                  Tetramethly pyrazine         -                  -     Protein
Indoles and        Indole              Intense fecal              -     Protein
Phenols          Skatole              Nauseating fecal            -     Protein
                  Phenol                      -                  .005   Protein
                  Ethyl phenol                -                   -     Protein
                  p-Cresol        Major odor in swine manure    .001    Protein
                                                    Odor threshold
___Class___       ___Compound___     ____Smell_____   ____ppm____      Substrate
Sulfur-containing Hydrogen sulfide   Rotten eggs          .0072      Protein & TM
Compounds         Dimethyl sulfide   Rotten eggs         .001        Protein & TM
                  Diethyl sulfide         -                 -        Protein & TM
                  Methyl mercaptan   Skunk                .002       Protein & TM
                  Ethyl mercaptan    Skunk               .001        Protein & TM

• Common divisions used in discussing odors
    –NH3
    –H2S
    –Volatile organic compounds
•No single chemical has been identified as a good indicator of odor
•Difficult to control odor by any single approach
• Measurement of odor
  – Gas measurement
     • Air samples are collected and analyzed for specific, individual
       gaseous compounds
     • Measured with:
         – Patches
         – Indicator tubes
         – Meters
         – Electronic sensors
         – Gas chromatograph/mass spectrometer
     • Advantages
         – Accurate measure of individual gases
             » Allows for specific numeric standards
             » Useful for measuring gaseous compounds with
               specific health effects
     • Limitations
         – Manure odor is not associated with any single compound
– Olfactometry
   • Odors are measured by a trained panel of humans
   • May be measured
      – On location
          » Scentometer
          » Field sniffer
      – In laboratory
          » Dynamic, triangular forced-air olfactometer
   • Characteristics to describe odor
       – Concentration
           » Detection threshold
             Volume of normal air needed to dilute odor sample to
             the point where the difference is detected by 50% of
             the panel members
           » Recognition threshold
             Volume of normal air needed to dilute an odor sample
             to the point that the panel can recognize the
             compound
       – Intensity
           » Describes the strength of the odor relative to different
             concentrations of n-butanol
       – Persistence
           » Amount of air needed to dilute air around a livestock
             unit to the point where the odor is not smelled
   – Hedonic tone
       » Measurement of the unpleasantness of an odor
       » Scale of measurement is 1 to 10
   – Character descriptors
       » A description of the smell
• Advantages
   – There is a direct correlation between odor and the sense of
     smell
   – Measures the complete mixture of gases
• Limitations
    – Olfactometry is subjective
        » Imprecise
        » Difficult to regulate
• Health effects of odors
   – Within buildings
      • Toxicity of two compounds
          – Ammonia
          – Hydrogen sulfide
      • Ammonia
      Concentrations, ppm Exposure ________Effects____________
         20                  -     Decreased disease resistance
          50               < 1 day     Eye and throat irritation
                                        Severe cough
           100                 6 weeks Impaired pulmonary function
          <150                 < 1 day Scarring of upper and lower airway
            500                 30 min Sore nose and throat
          <1000                   -     Irritation of upper respiratory
                                         tract
          >4000                   -     Severe damage to upper and
                                         and lower respiratory tract
          5000                 < 30 min Death
          – Smells at 50 ppm
    • Hydrogen sulfide
        – Most dangerous of gases
        – Colorless
        – Can be smelled at 1 ppm, but concentrations > 150 ppm inhibits
          smell
            » Makes H2S particularly dangerous
            » Requires monitoring equipment
        – Gas is heavier than air
            » Concentrates in pits and holding tanks
            » Dangerous when agitated
        – Acute toxicity
Concentration, ppm Exposure        Human effects        Swine effects
      100           > 1 hr      Eye and nose irritation    None
      200             1 hr      Headache, dizziness           -
      375             4 hr              -               Pulmonary edema
      500            30 min     Nausea, excitement,          -
                                insomia
     >500              -        Severe pulmonary edema       -
     1000              -        Unconsiousness,         Spasms, convulsions
                                death                   cyanosis, death

        – Chronic toxicity
            » Occurs at long-term exposure at 300 ppm
            » Symptoms
              Asthma, bronchitis, sinusitis, hay fever, progressive loss of lung
              function, chronic obstructive pulmonary disease
– Effects of H2S on lungs are uniform throughout the
  respiratory tract
    » Particularly damaging to deep pulmonary structures, causing
      edema
– Toxicity effects
    »   Binds mitochondrial cytochrome oxidase
    »   Blocks oxidative phosphorylation and ATP production
    »   Causes build up of lactic acid in body
    »   Neurophysiological abnormalities
        Impaired balance
        Impaired hearing
        Impaired memory
        Impaired mood
        Impaired intellectual function
– Workplace limit
   » 10 ppm H2S
– Community effects
   • Response to NH3, H2S, and VOCs
   • Symptoms
       –   Headache
       –   Runny nose
       –   Sore throat
       –   Coughing
       –   Diarrhea
       –   Burning eyes
       –   Negative mood (Tension, depression, anger, fatigue, confusion)
   • Odor recommendations
       – Based on dilution ratio of clean air:air from livestock operation
       – Odor shall not exceed a 7:1 dilution at a residence in two periods/day for
         more than 7 days per year
       – Odor shall not exceed a 15:1 dilution at the property line for one
         period/day for more than 14 days per year
   • Factors affecting odor complaints
       – Frequency of problem
            » 86% of farmers tolerate neighbor’s odor if problem occurs > 2
              days/year
            » 50% of farmers tolerate neighbor’s odor if problem occurs > 10
              days/year
       – Intensity of problem
       – Duration of problem
       – Offensiveness of odor
       – Relations with neighbors (Time of residence, previous contact)
       – Odor plume (Direction, topography)
• Origin of livestock odor
                                              Odor compound
Large intestine     Carbohydrates                                           Protein
                  (Starch, cellulose)         Volatile fatty acids
                                        (Acetic, Propionic, Butyric acids;
                                         may be absorbed or excreted)

                                             H2S and mercaptans
                                               (Passed as gas)
                                          Other amines, phenols, and
                                          indoles (Absorbed from LI &
                                         excreted in urine)

Manure              Carbohydrates
(Secondary                              Volatile fatty acids and alcohols    Protein
fermentation          Lactic acid
greater at:                                   Butyric acid
Manure pH > 4.5;
High manure moisture;                    NH3, H2S, mercaptans, branched
High ambient temperatures)                chain VFAs (Isobutyric, Isovaleric),         CH 4
                                         Amines (Putrescine, Cadaverine),
                                         Phenols (Phenol, p-Cresol),
                                         Indoles (indole, Skatole)

Air    Emissions increased with increased temperature, moisture, humidity, agitation,
       dust, pH, wind, surface exposure
• Livestock management to reduce odors
  – Reduce excessive protein feeding
     • Reducing protein swine diets from 18 to 14% reduced odor
       components by 40 to 86%
     • Nonruminants
         – Balance essential amino acids to create ideal dietary protein with
           crystalline amino acids
         – Use multi-phase and split-gender feeding
         – Avoid safety margins in protein feeding
         – Use genetically lean pigs
         – Use growth promoters
         – Minimize feed waste
     • Ruminants
         – Supply only enough ruminally degraded protein to meet the NH3
           needs of the rumen bacteria
         – Beyond the microbial NH3 needs, meet animal’s metabolizable protein
           needs with ruminally undegrade protein sources or crystalline amino
           acids
         – Use phase feeding of beef feedlot or dairy cows
         – Control feed wastes
  – Reduce sulfur in mineral supplements
     • Can reduce odor by 40%
     • Utilize salts other than sulfates or sulfides for trace minerals
– Increase cellulose or other nonstarch polysaccharides in
  swine diets
   • Causes bacteria in large intestine to incorporate NH 3 into
     microbial protein
   • Reduces NH3 by as much as 35%
   • Ingredients to add:
       – Soy hulls
       – Sugar beet pulp
       – Distillers grains
– Mask odor with other odors
   • Garlic powder has been used for poultry
– Feeding sarsaponin
   • Extracted from yucca plant
   • Inhibits urease
– Feeding zeolites
   • Minerals that have cation exchange capacity
       – Binds odor compounds
– Reduce dust from animals’ skin
   • Increase quality of dietary fat
   • Feed adequate zinc
• Management of livestock facilities to manage manure
  odor
   – Frequent cleaning of wet manure and feed from facilities
      • Manure standing for more than 5 days will cause considerable
        offensive odor
   – Use bedded systems
      • Odor seems less offensive than liquid systems
      • Addition of organic matter from bedding reduces odor
   – Reduce dust within and outside buildings
      • Approaches
          – Frequent cleaning
          – Spraying vegetable oils
               » Reduce NH3 and H2S by 30%
               » Spray once daily
               » Use a medium droplet size
               » Problem with oily facilities
          – Installation of wet scrubbers
               » Wetted pads 3 to 5’ in front of ventilation fans
               » Traps dust with some NH3, H2S, and NOx
               » Effectiveness on odors?
   – Use of chemical additives
      • Alum (K Al(SO4)) will reduce some NH3 emissions
– Use Biofiltration
   • A system that uses aerobic bacteria to degrade gaseous odors
     from ventilated air
   • Process
                             Aerobic bacteria
   VOC & inorganic gases                        CO2 + H2O + Mineral salts +
                                                Microbial biomass
   • Fiber mat serves as media
       – Shredded wood and compost (50:50)
       – Shredded wood and soil (50:50)
       – Straw and compost
   • Less effective during periods of high ventilation
   • Can be difficult to control vegetation and rodents
– Use Biomass filters
   • Walls of corn stalks, corn cob or other materials placed
     immediately outside ventilation fans
   • Effects
       – Reduces dust by 52 – 83%
       – Reduces odor by 43 – 90%
– Use windbreak walls
   • Walls placed 10 – 20 ft downwind from ventilation fans
   • Effects
       – Settle dust near barn
       – Disperses odor plume upward to increase dilution




– Use natural windbreaks
   • Rows of trees or other vegetation
   • Effects
       – Trap dust
       – Aids in dispersion and dilution of odor
       – Provides a visual barrier
• Management of manure storage to limit odor
  – Aerobic treatment
     • Liquid manure
        – Air is pumped into liquid manure
        – Should oxidize odor-causing chemicals
        – Difficult to mix enough O2 to be effective
     • Solid manure
        – Composting
            » Requirements
               Appropriate moisture (50%)
               Adequate C:N ration (>20:1)
               Aerobic conditions   (Frequent mixing)
               Temperature          (130 oF for 3 days)
        – Oxidizes odor and incorporates N-containing compounds into
          microbial protein
        – Effects
            » Reduces odor by 75% in 2 weeks
– Management of anerobic lagoons
   • Complete anerobic digestion is effective at limiting odors




   • Odors can be controlled if:
       – Loading rate is slow and uniform enough to allow balance of
         bacteria producing VFAs or CH4
           » Allows development of purple sulfur-oxidizing bacteria
             Metabolize VOCs
             Reduce amines
             A purple or pink color of lagoon is desirable
• Factors affecting odors in lagoons
    – High loading rates
        » Excess animal numbers
        » Inadequate dilution water
    – Windy conditions
        » Disturbs surface
    – Timing of agitation and pumping for application
        » Should be done on clear, sunny days when warm air causes
           odors to rise and disperse
    – Early spring turnover
        » Odor problems increase as bacterial action begins to
           increase digesting nutrients that were incompletely
           metabolized over winter
– Use covers over storage facilities
   • Covers over manure structures
      – Rigid covers
           » Concrete, wood, fiberglass, plastic
           » Materials must be noncorrosive
       – Flexible covers
           » Tarp over manure with a blower
   • Floating covers
       – Natural
           » Crust floating on top of manure
       – Artificial organic
           » Straw, chopped corn stalks, wood shavings
       – Artificial
           » Polystyrene foam, air-filled clay balls, geotextile
       – Effectiveness
           » Provides a barrier between liquid manure and the
              atmosphere
           » Provides aerobic media to all microbes to degrade
              odor compounds
           » Limitations
              Straw will only last from 2 weeks to 6 months
– Anerobic digesters
   • Produce methane for biogas
   • Reduce odors by 70 – 80%
– Additives
   • Biological
       – Microbial additives
           » Cultures added to degrade odor compounds
           » Effectiveness?
   • Chemical
       – Oxidizers and pH control
           » Limited effectiveness
       – Masking agents
           » Volatile compounds that smell pleasant
           » Sprayed on or above manure
           » May separate from manure downwind
       – Absorbents and Adsorbents
           » Activated carbon, zeolite, bentonite, or sphagnum moss
           » Effectiveness?
       – Antimicrobial oils
           » Includes plant oils like thymol and carvacol
           » Inhibit microbial degradation of manure during anerobic
             storage, but degrade in aerobic conditions after application
           » Preserves nutrients and reduces odor emissions
           » Still in research
           » Economics?
– Natural windbreaks
   • Creates a visual barrier
   • Filters, disperses and dilutes odor
– Separation of manure solids and liquid
   • Can be mechanical or gravity
   • Separates urea in urine from urease in feces
   • Effects
       – Reduces NH3
       – Reduces odor by 50%
• Manure application management to control odors
  – Manure odor problems are directly proportional to the surface
    area for emissions
     • The area of manure application is the greatest source of manure
       odor
  – Factors affecting manure odor during application
     • Form of manure
         – Earthen basin > Below barn pit > Anerobic lagoon > Solid > Compost
     • Lagoon management
         – Lagoon should be large enough to leave a permanent pool to
           stabilize microbial population
         – Apply in June through fall
             » Odors reduced when microbes are most active
         – Dilute manure with water liberally
             » 2 – 3 parts H2O : 1 part manure
         – Test for salt and NH3 concentration
         – Stop lagoon feeding 2 weeks before pumping
             » Allows bacteria the opportunity to degrade odor
     • Application method
         – Injection of manure into soil
             » Most effective at preventing odors
         – Surface application with incorporation
             » Must be done immediately after application
– If surface applying liquid manure by irrigation make sure
  to:
     » Set sprayer for large droplets
      Reduce droplet surface area
    » Adequately dilute manure with clean water
      2:1
    » Monitor wind direction
      Shut down if wind blows towards neighboring residences
    » Monitor wind spead
      Shut down if wind speed exceeds 5 mph
      Prevents dilution of odor
• Consideration of neighbors as a method to control
  manure odor nuisance complaints
   – Siting of operation and fields for manure application
      • Major tool to limit odor nuisance complaints
      • Considerations
         – Distance
              » Odors decreases exponentially with distance
              » Distances (Required to use the Master Matrix)
                > Residences
                        >¼ mile from buildings
                        >750 ft from manure application-Surface applied
                > Residential development
                        >1 mile from buildings
                        >750 ft from manure application-Surface applied
         – Topography
              » Don’t build uphill from residences
         – Prevailing winds
              » Don’t build so residences are downwind of the
                prevailing winds
                Especially during the spring
         – Building orientation
              » Short side of livestock facility should be perpendicular
                to the neighbor’s residence
– Timing of manure application
   • Tell neighbors when you plan to spread manure
   • Select days when wind is blowing away from neighbors
   • Avoid spreading manure on weekends, holidays, or on days
     when neighbors have a social event planned
– Facility maintenance
   • Maintain buildings and grounds around facilities
       – Mow grass
       – Control weeds
   • Proper dead animal disposal
   • Avoid spilling manure on roads

								
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