Pollutants organic contaminants

Catalytic combustor A device used to remove various solid, liquid, or gaseous pollutants from air or another gas, in which the gas is heated by an open burner to between 250 and 500 °C and passed through a catalyst bed in which the organic contaminants are oxidized into harmless by-products. 

In addition to hazardous substances, CERCLA addresses pollutants and contaminants, which are broadly defined to include any substance that is reasonably anticipated to cause illness or deformation in any organism. All three definitions specifically exclude petroleum and natural gas. 

Factors that affect the accessibility of chemicals to plant roots include hydrophobicity, polarity, sorption properties and solubility. In order to apply phytoremediation techniques to soils polluted by organic contaminants, the contaminant must come into contact with the plant roots and be dissolved... 

Hartlieb N, Ertunc T, Schaeffer A, Klein W (2003) Mineralization, metabolism and formation of non-extractable residues of 14C-labelled organic contaminants during pilot-scale composting of municipal biowaste. Environ Pollut 126 83-91... 

Fig. 12. Scenario for the in-situ modification of subsoils or aquifers for pollution control. The organoclay formed by injecting a solution of long-chain quaternary ammonium cations (e.g. HDTMA) acts as a sorptive zone where organic contaminants dissolved in a plume from buried waste can be immobilised and degraded. After Xu et al. (1997).

Bioavailability issues have been reviewed previously (Mihelcic etal. 1993 Boesten 1993 Baveye and Bladon 1999 Ehlers and Luthy 2003). In this review, we discuss specifically the bioavailability of soil- or sediment-sorbed organic contaminants to pollutant-degrading bacteria. Direct uptake of sorbed contaminants is perhaps the most controversial and least understood process. The definition of bioavailability given by Alexander (2000) will be used in this review. The term bioaccessibility encompasses what is immediately available plus that which may become available, whereas bioavailability refers to what is available immediately. 

Zoeteman, B.C.J., De Greef, E., Brinkmann, F.J.J. (1981) Persistency of organic contaminants in groundwater. Lessons from soil pollution incidents in the Netherlands. Sci. Total Environ. 21, 187-202. 

Burgess RM, Terletskaya AV, Milyukin MV et al (2009) Concentration and distribution of hydrophobic organic contaminants and metals in the estuaries of Ukraine. Mar Pollut Bull 58 1103-1115... 

Steimle, F.W., V.S. Zdanowicz, and D.F. Gadbois. 1990. Metals and organic contaminants in northwest Atlantic deep-sea tilefish tissues. Mar. Pollut. Bull. 21 530-535. 

The net result of sorption on organic contaminated soils is to retard the movement of contaminants. When a pollutant is adsorbed onto soil, it can be released only when the equilibrium between it and the passing fluid (water or air) is disrupted. Retardation is the term used to describe the apparent discrepancy between the actual migration rate of aquifer water and that of a dissolved organic chemical (somewhat slower). The difference in travel rates is the result of sorption of the chemical onto the aquifer matrix and release into water by the concentration gradient and time of contact. A general equation used for gross estimation of the retardation factor Rj is... 

Roberts, R V., McCarty, P. L., Reinhard, M., and Schreiner, J., 1980, Organic Contaminant Behavior during Groundwater Recharge Journal of Water Pollution Control, Vol. 2, pp. 161-172. 

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