Formaldehyde pollution control

Otner Collectors Tarry particulates and other difficult-to-handle hquids have been collected on a dry, expendable phenol formaldehyde-bonded glass-fiber mat (Goldfield, J. Air Pollut. Control A.SSOC., 20, 466 (1970)] in roll form which is advanced intermittently into a filter frame. Superficial gas velocities are 2.5 to 3.5 m/s (8.2 to 11.5 ft/s), and pressure drop is typically 41 to 46 cm (16 to 18 in) of water. CoUection efficiencies of 99 percent have been obtained on submicrometer particles. Brady [Chem. Eng. Prog., 73(8), 45 (1977)] has discussed a cleanable modification of this approach in which the gas is passed through a reticulated foam filter that is slowly rotated and solvent-cleaned. 

Hawthorne, A., et al. (1987) Models for estimating organic emissions from building materials formaldehyde example. Atmos. Environ. 21, No. 2. Lewis, R. G., et al. (1986) Monitoring for non-occupational exposure to pesticides in indoor and personal respiratory air. Presented at the 79th Annual Meeting of the Air Pollution Control Association, Minneapolis, MN. 

Bhattacharya, S.K. and Parkin, G.F., Fate and effect of methylene chloride and formaldehyde in methane fermentation systems, J. Water Pollut. Control Fed., 60, 531-536, 1988. 

Pitts, J. N., Jr., H. W. Biermann, E. C. Tuazon, M. Green, W. D. Long, and A. M. Winer, Time-Resolved Identification and Measurement of Indoor Air Pollutants by Spectroscopic Techniques Nitrous Acid, Methanol, Formaldehyde, and Formic Acid, J. Air Pollut. Control Assoc., 39, 1344-1347 (1989). 

Godish T, Fell J, Lincoln P. 1984. Formaldehyde levels in New Hampshire urea - formaldehyde foam insulated houses. Relationship to outdoor temperature. J Air Pollut Control Assoc 34 1051-1052. 

Kulle TJ, Sauder LR, Hebei JR, et al. 1987. Formaldehyde dose-response in healthy nonsmokers. J Air Pollut Control Assoc 37 919-924. 

Matthews TG, Fung KW, Tromberg BJ, et al. 1986. Impact of indoor environmental parameters on formaldehyde concentrations in unoccupied research houses. J Air Pollut Control Assoc 36 1244-1249. 

Meyer B, Hermanns K. 1985. Reducing indoor air formaldehyde concentrations. J Air Pollut Control Assoc 35 816-821. 

Sexton K, Liu K-S, Petras MX. 1986. Formaldehyde concentrations inside private residences A mail-out approach to indoor air monitoring. J Air Pollut Control Assoc 36 698-704. 

Lyles, G. Dowling, F. Blanchard, V. "Quantitative Determination of Formaldehyde in the Parts Per Hundred Million Concentration Level" J. Air Pollution Control Association,... 

Matthews T. G., Wilson D. L., Thomson A. J., Mason M. A., Bailey S. N. and Nelms L. H. (1987) Interlaboratory comparison of formaldehyde emissions from particle board underiayment in small scale environmental chambers. Journal of the Air Pollution Control Association, 37, 1320-1326. 

Metal oxide catalysts are extensively employed in the chemical, petroleum and pollution control industries as oxidation catalysts (e.g., oxidation of methanol to formaldehyde, oxidation of o-xylene to phthalic anhydride, ammoxidation of propylene/propane to acrylonitrile, selective oxidation of HjS to elemental sulfur (SuperClaus) or SO2/SO3, selective catalytic reduction (SCR) of NO, with NHj, catalytic combustion of VOCs, etc.)- A special class of metal oxide catalysts consists of supported metal oxide catalysts, where an active phase (e.g., vanadium oxide) is deposited on a high surface area oxide support (e.g., alumina, titania, ziiconia, niobia, ceria, etc.). Supported metal oxide catalysts provide several advantages over bulk mixed metal oxide catalysts for fundamental studies since (1) the number of surface active sites can be controlled because the active metal oxide is 100% dispersed on the oxide support below monolayer coverage,... 

Additional analysis is necessary when one considers energy-related emissions. First, a description of the energy-related emission factors will be presented. Assuming that coal is burned for electricity generation [75], and using an EPA report [76] for the amount of mercury in coal and emitted after pollution controls (assuming 90% capture), the controlled emission rate is 5.58 x 10 kg mercury/kWh. For the benzene, toluene, formaldehyde, and hexane emissions from coal-fired electricity generation, EPA and... 

Aldehydes are the most important class of oxygenates in facilitating the generation of ozone. They react rapidly with OH radicals, and they photolyze readily. As seen in table I-D-1, the urban concentrations of formaldehyde and acetaldehyde are often quite high, especially in areas with limited or no pollution controls. Obviously, the rates of generation of aldehydes must be large to sustain the observed concentrations in the face of rapid removal reactions. Even the larger aldehydes are detectable in many urban atmospheres. 

Good indoor air quality, critical for a healthy home, requires effective control of pollutants and moisture. To some extent this can be accomplished by thoughtfully selecting materials that contain low levels of volatile organic compounds and formaldehyde. In addition, hard surfaces that can be easily... 

The development of new models for the prediction of chemical effects in the environment has improved. An Eulerian photochemical air quality model for the prediction of the atmospheric transport and chemical reactions of gas-phase toxic organic air pollutants has been published. The organic compounds were drawn from a list of 189 species selected for control as hazardous air pollutants in the Clean Air Act Amendments of 1990. The species considered include benzene, various alkylbenzenes, phenol, cresols, 1,3-butadiene, acrolein, formaldehyde, acetaldehyde, and perchloroethyl-ene, among others. The finding that photochemical production can be a major contributor to the total concentrations of some toxic organic species implies that control programs for those species must consider more than just direct emissions (Harley and Cass, 1994). This further corroborates the present weakness in many atmospheric models. 

Assessment and control of indoor air pollution. Report to Congress on Indoor Air Quality, Vol. 1, Office of Air and Radiation, U.S. Environmental Protection Agency, 1989 Formaldehyde risk-assessment update. Office of Toxic Substances, U.S. Environmental Protection Agency, Washington, D.C., June 11, 1991. 

For NO t > 0-5 ppb (typical of urban and polluted rural sites in the eastern USA and Europe) Equations (3) and (4) represent the dominant reaction pathways for HO2 and RO2 radicals. In this case the rate of ozone formation is controlled largely by the rate of the initial reaction with hydrocarbons or CO (Equations (1) and (2)). Analogous reaction sequences lead to the formation of various other gas-phase components of photochemical smog (e.g., formaldehyde (HCHO) and PAN) and to the formation of organic aerosols. 

Inasmuch as the indoor environment has the purpose to shelter occupants of buildings, it intrinsically tends to confine indoor pollutants. Sofar some 300 such pollutants have been identified (10) and, as mentioned earlier, radon and formaldehyde ( may reach occupational threshold levels. Indoor air quality is controlled by a... 

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