Volatile organic compounds removal processes

Liquid nitrogen is used in cold traps to remove and recover solvents or volatile organic compounds from gas streams to reduce atmospheric emissions. Liquid nitrogen can be used to accelerate the cooldown time for process reactors (29). 

Clark, R. M. (1990). Unit process research for removing volatile organic chemicals from drinking water An overview. In Significance and Treatment of Volatile Organic Compounds in Water Supplies, (N. M. Ram, R. F. Christman, and K. P. Cantor, eds.), Lewis Publishers, Chelsea, ML... 

Soil vapor extraction (SVE) is a relatively new yet widely applied technology for the remediation of soils contaminated with volatile organic compounds (VOC) in the unsaturated zone above the water table (vadose zone). The process consists of generating an airstream through the contaminated soil subsurface in order to enhance the volatilization of organic contaminants and thus remove them from the soil matrix.913... 

In addition to the aforementioned issues regarding the incineration process, other concerns of relevance to public health need to be addressed. For example, hazardous waste to be fed to the incinerator and process effluents resulting from the incinerator should be stored in a manner that does not allow for uncontrolled environmental releases of potentially harmful substances. Dry, dusty materials should be enclosed or otherwise stored to prevent windborne transport of contaminated particulates. Wastes containing volatile organic compounds should be stored under conditions that safely collect and remove gases released from the wastes. 

Kersten A, Putz H-J, Schabel S (2010) Volatile organic compounds in printed papers and measures for removal in recovered paper processing. In 9. Research Forum on Recycling, Norfolk... 

CADRE A process for removing and oxidizing volatile organic compounds from gas streams. The compounds are adsorbed on a fixed bed of carbon and then desorbed by a stream of hot air or inert gas. Developed by Vard International, a division of Calgon Carbon Corporation. 

Kryoclean A process for removing volatile organic compounds from effluent gas streams by low-temperature condensation. The refrigerant is liquid nitrogen, used subsequently in various ways. Developed by BOC in the 1990s. A simplified version of the process was announced in 1997. 

Polyad [Polymer adsorbent] Also written POLYAD. A family of processes for removing volatile organic compounds from air streams by continuous adsorption on an adsorbent and desorption with hot air. Several adsorbents are used, depending on the sorbate, including a macroporous polymer ( Bonopore ). Used for control of emissions and for solvent recovery. COMBI-AD is a variant for simultaneously removing several solvents, using two different adsorbents. Developed and offered by Chematur Engineering, Sweden. Twelve units had been installed, in several countries, by 1995. 

Limited data is available on the concentration of volatile organic compounds, semi-volatile organic compounds (SVOCs), and polycyclic aromatic hydrocarbons (PAHs) from gasification processes. The data that is available indicate that VOCs, SVOCs, and PAHs are either non-detectable in flue gas streams from IGCC process or, in some cases where they were detected, they are at extremely low levels (on the order of parts per billion and lower). The analysis of syngas also indicates greater than 99.99 percent chlorobenzene and hexachlo-robenzene destruction and removal efficiencies and part per billion or less concentration of selected PAHs and VOCs.9-14... 

Bisschops, M. A. T., van der Wielen, L. A. M. and Luyben, K. Ch. A. M. in Semel, J. (ed) Process Intensification in Practice, Applications and Opportunities (BHR Group, London, 1999) 229. Centrifugal adsorption technology for the removal of volatile organic compounds from water. 

Wang et al. [42,67,68] have developed innovative biological process and sequencing batch reactors (SBR) specifically for removal of volatile organic compounds (VOCs) and surfactants. Related analytical procedures [57-64,71-91] available for process monitoring and control are available in the literature. 

Advanced Soil Technologies (AST) offers the AST thermal desorption system for the treatment of soil contaminated with volatile organic compounds (VOCs). The process heats the soil to remove the targeted contaminants, which are then destroyed in a secondary treatment chamber. The technology has been available commercially. RIMS was unable to contact the vendor. 

The Biocube aerobic biofilter is an ex situ off-gas filtration system that is commercially available. The technology utilizes microbes to biologically oxidize volatile organic compounds (VOCs) and complex odors. It can be used in conjunction with vapor-vacuum-extraction (VVE), a process that draws gases from subsurface soil. These gases often require further treatment before being released into the atmosphere. Biocube has been field tested and has been implemented at over 100 sites for the treatment of hydrocarbon vapors. The technology has also been successfully used for odor control at a variety of sites. In addition, the Biocube system can treat odor and VOC emissions simultaneously. The units are modular, so additional stacks can be added as needed for increased flow and/or removal rates. 

CESAR was developed to address the problem of locating, characterizing, and removing dense non-aqueous-phase liquids (DNAPLs) from contaminated aquifer systems. The process is particularly suited to remediating groundwater contaminated with chlorinated solvents, such as trichloroethylene (TCE), tetrachloroethene (PCE), trichloroethane (TCE), and carbon tetrachloride (CCE). According to the vendor, CESAR can also be applied to sites contaminated with creosote, polychlorinated biphenyls (PCBs), Freon 113, volatile organic compounds (VOCs),... 

The HRUBOUT process is a mobile in situ or ex situ thermal desorption process designed to remediate soils contaminated with volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs). For the ex situ process, excavated soil is treated in a soil pile or in a specially designed container. Heated compressed air is injected into the soil, evaporating soil moisture and removing volatile and semivolatUe contaminants. Heavier hydrocarbons are oxidized as the soil temperature is increased to higher levels over an extended period of time. The vapor is collected and transferred to a thermal oxidizer (incinerator) for destruction. 

The vendor claims that the technology will treat uranium and possibly thorium. At this point, the technology has only been bench tested. The vendor hopes, however, that once the heap leaching technology is fully developed, it will be used to remove metals chemically (uranium in this case) from soil without damaging the soil. With some modification, the process can also be used to remove volatile organic compounds from soil by ex situ soil venting. 

The Terra Vac vacuum extraction process is a patented, in situ process used to remove volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) from contaminated... 

Chemical contaminants for which full-scale treatment data exist include primarily volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs). These SVOCs include polychlorinated biphenyls (PCBs), pentachlorophenol (PCP), pesticides, and herbicides. Extremely volatile metals, such as mercury and lead, can be removed by higher temperature thermal desorption systems. The technology has been applied to refinery wastes, coal tar wastes, wood-treating wastes, creosote-contaminated soils, hydrocarbon-contaminated soils, mixed (radioactive and hazardous) wastes, synthetic mbber processing wastes, and paint wastes. 

The two-phase extraction process is a removal technology designed particularly for use in low conductivity formations such as silts and clays that are impacted by volatile organic compounds (VOCs). This technology removes VOCs from groundwater and/or soils. 

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