Malodorants vapors

PR valves discharging vapors which do not fall into the above categories but which would be significant contributors to atmospheric pollution. Such releases should not normally be used to size the closed system but should be tied in up to the limit of its capacity. The order of preference for tying in is (1) malodorous vapors, (2) unsaturated hydrocarbons, (3) saturated hydrocarbons. If local requirements do not permit such atmospheric discharges, it will be... 

Malodorants are primarily an inhalation hazard. Aerosols and vapors are extremely foul smelling at low concentrations but are otherwise relatively nontoxic. However, exposure to bulk liquid or solid agents may be hazardous through skin absorption, ingestion, and introduction through abraded skin (e.g., breaks in the skin or penetration of skin by debris). 

Malodorants are primarily an inhalation hazard however, at elevated vapor/aerosol concentrations or in contact with bulk material, agents may also pose a dermal hazard. 

Designing emergency ventilation systems to capture fugitive emissions of toxic, corrosive, or malodorous gases or vapors. 

Foul-smelling fumes from the crude sulfate turpentine escaped the tanks both during tank fillings and during the daytime, when the sun increased the tank temperature. Malodorous tank vapors were routine. Company personnel planned to solve the problem by routing these offensive fumes to drums with activated carbon. [11,12]... 

The effluent streams from Claus plants contain unreacted hydrogen sulfide and sulfur dioxide and elemental sulfur present as vapor and mist (77). They commonly also contain carbonyl sulfide and carbon disulfide formed by reactions with hydrocarbons present in the feed gas (77). It is usually required that the tail gas be incinerated, even though not otherwise treated, to convert the hydrogen sulfide, carbonyl sulfide, and carbon disulfide to the less toxic and malodorous sulfur dioxide. 

Arsenic is a gray crystalline solid that does not melt at atmospheric pressure but simply volatilizes to give a dense, malodorous yellow vapor. Its main use as an element is to harden lead-antimony alloys, for example, those in storage batteries or lead shot. Arsenic compounds are highly toxic hence, many have been used as potent herbicides and insecticides. 

Removal of organic odors is a much more complex problem. Wet scrubbing using a combination of absorbent and oxidant has successfully reduced such odors [11]. The malodorous substance first is absorbed into the liquid phase then the oxidant converts the absorbed contaminant to a less odorous substance. This sequence eliminates the normal Henry s Law vapor pressure that would be exhibited if the malodorous material simply were absorbed into water. 

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