Biodegradation scale

Table 4.11 Oil biodegradation scale (after Peters Moldowan 1993)...

A depol5nnerized carboxyl alkyl guar with a degree of substitution of up to 3 carboxylic groups per sugar unit can be used as a scale inhibitor in oilfield applications (40 This is a biodegradable scale inhibitor which is effective under severe scaling conditions. 

R. N. Miller, "A Field-Scale Investigation of Enhanced Petroleum Hydrocarbon Biodegradation ia the Vadose Zone Combining Soil Venting as an Oxygen Source with Moisture and Nutrient Addition," doctoral dissertation submitted to the Civil and Environmental Engineering Department,... 

Bioremediation also has its limitations. Some chemicals are not amenable to biodegradation, for instance, heavy metals, radionuclides, and some chlorinated compounds. In some cases, the microbial metabolism of the contaminants may produce toxic metabolites. Bioremediation is a scientifically intensive procedure that must be tailored to site-specific conditions, and usually requires treatability studies to be conducted on a small scale before the actual cleanup of a site.13 The treatability procedure is important, as it establishes the extent of degradation and evaluates the potential use of a selected microorganism for bioremediation. A precise estimate on vessel size or area involved, speed of reaction, and economics can therefore be determined at the laboratory stage. 

A full-scale cleanup was performed using in situ bioremediation to treat MTBE and BTEX at a service station in Massachusetts. Soil at the site consists of a layer of sand and gravel underlain by peat, silt, and clay. The in situ bioremediation system consisted of 12 injection wells and two butane injection panels used to stimulate cometabolic aerobic biodegradation of the contaminants in groundwater. The system was operated between October 2000 and January 2001. MTBE concentrations were reduced from 370 to 12 pg/L and BTEX contamination in groundwater was reduced by approximately two orders of magnitude during the 4-month period.74... 

The following scale has been proposed to assist discussions of biodegradability [216,217] ... 

Hanggi UJ (1990) Pilot scale production of poly(3HB) with Alcaligenes latus. In Dawes EA (ed) Novel biodegradable microbial polymers. Kluwer, Dordrecht, p 65... 

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